Chemistry, safety, and regulatory considerations in the use of nitrite and nitrate from natural origin in meat products - Invited review

Pulsed light and jabuticaba peel extract for nitrite reduction and quality enhancement in sliced mortadella

This study evaluated using pulsed light (PL) and jabuticaba peel extract (JPE) to control bacterial growth in sliced mortadella with reduced sodium nitrite content and assessed their impact on food quality. Three formulations were tested: 150 ppm nitrite (100 % of the allowed dosage, N100%), 75 ppm nitrite (N50%), and 75 ppm nitrite with 1 % JPE (N50% + JPE). The mortadella was cooked, sliced, treated with PL (5.28 J/cm2 fluence, 1046.9 W/cm2 irradiance), vacuum-packed, and stored at 4 °C for 30 days. N50% samples exhibited higher TBARS values (0.54 vs. 0.18 mg MDA/kg) and higher population counts of total mesophilic aerobic bacteria (TMAB, 8.38 vs. 7.1 Log CFU/g) and lactic acid bacteria (LAB) (8.21 vs. 6.17 Log CFU/g, respectively) than N100% after 30 days of storage. PL application reduced the TMAB and LAB by 1.4-1.55 Log CFU/g and 1.0-2.24 Log CFU/g for the N100% and N50% formulations (P < 0.05), respectively, but negatively affected pH and color, increasing lipid oxidation. JPE mitigated these defects, and combined JPE and PL presented an enhanced antimicrobial effect, with N50% + JPE + PL samples showing similar microbial counts to N100% over the storage. The combination of JPE and PL also significantly reduced nitrosamine levels, highlighting it as an effective strategy to improve the quality and safety of meat products.

Nanoarchitectured biomass-waste derived activated charcoal nanozymes and its application in visual analysis of nitrite in pickled food

The emerging field of nanozymes has introduced unprecedented opportunities and challenges for activated charcoal materials derived from biomass waste. By incorporating specific nanostructures or elements, it is possible to overcome the limitations of traditional activated charcoal, such as insufficient catalytic active sites and poor electron transfer efficiency, thereby unlocking its full potential for various applications. In this study, we successfully synthesized trace Fe-doped activated charcoal (Fe-AC) with a graphene-like structure from biomass waste. The Fe atoms were uniformly dispersed on the activated charcoal support, which possessed a high surface area. This not only significantly increased the number of catalytic active sites but also enhanced electron transfer efficiency, substrate mobility, and collision probability. Compared to pristine activated charcoal, the synthesized Fe-AC exhibited multiple enzyme-mimetic activities, including oxidase-like, peroxidase-like, and catalase-like activities. By leveraging its peroxidase-like activity in conjunction with nitrite-specific diazotization reactions, we developed a portable, smartphone-assisted, on-site ratiometric colorimetric hydrogel sensor for nitrite detection. Utilizing smartphone-based digital imaging, this sensor enabled the quantitative analysis of nitrite at concentrations ranging from 1 to 200 μmol/L, with a detection limit as low as 1 μmol/L. The approximate range of hazardous nitrite concentrations could be easily identified with the naked eye, and the proposed strategy was successfully applied to real sample analysis. This sensor not only maximizes the utilization of waste resources, thereby reducing production costs, but also offers greater economic feasibility and environmental sustainability. Given these advantages, it holds promise for broader applications in various fields.

A chitosan-based fluorescence probe for the detection of nitrite in food samples

Polysaccharides, as a natural biomolecule, are abundantly available in nature and have good bioactivity. They contain several functional groups such as hydroxyl, carboxyl, and amino groups, which can exhibit different fluorescent property after modification. In this work, the chitosan (CS) was selected as a raw material and grafted with methotrexate (MTX) to prepare a nitrite sensor. The sensing material exhibited obvious aggregation-induced emission (AIE) properties and could react with nitrite under acidic conditions to form diazo compounds that could enhance fluorescence. This "enhanced-luminescent" mode fluorescence probe for nitrite (NO2-) displayed superior sensing performance, such as excellent sensitivity, good selectivity, a low detection limit (0.22 μM) and wide detection range from 0 to 120 μM. Moreover, this sensor was effectively applied to detect nitrite in sausage samples. Finally, CS-MTX also showed excellent biocompatibility, good water solubility and outstanding antibacterial performance against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli). These results demonstrated that it may be a potent multifunctional material for nitrite detection and anti-bacteria in food industry.

Replacing preservative E 252 with powdered dried sumac (Rhus coriaria L.) fruits in "Suino Nero dei Nebrodi" salamis: Effects on microbiological, physicochemical, and antioxidant properties

The aim of this study was to develop health-oriented fermented salamis by replacing synthetic preservative (E 252) with dried Sumac (Rhus coriaria) fruit powder (DSFP). The salamis were produced at an industrial scale using meat from the "Suino Nero dei Nebrodi" breed, without adding starter cultures. The experimental design included four different salami productions: CTR, control production without nitrate salt and DSFP; CMC, commercial control production with nitrate salt but without DSFP; EXP1, experimental production without nitrate salt but with DSFP; and EXP2, experimental production with both nitrate salt and DSFP. Plate counts showed that DSFP did not inhibit the growth of lactic acid bacteria (LAB), coagulase-negative staphylococci, and yeasts, all of which reached approximately 7.0 log CFU/g in 45 d ripened salamis. Except for the CTR production, Escherichia coli levels decreased to undetectable amounts at 30 d of ripening. Culture-independent methods identified 16 taxonomic groups, with LAB being the predominant group across all trials, comprising 46.05-81.81 % of relative abundance (RA) in 45 d ripened salamis. Physicochemical analysis indicated that adding DSFP increased antioxidant activity by nearly 30 % and reduced primary lipid oxidation to levels comparable to those achieved with nitrate salt. The addition of DSFP in CMC, EXP1, and EXP2 salamis resulted in an approximate 11 % increase in total terpene aromatic profiles. Sensory evaluation indicated that the addition of DSFP did not impact overall acceptability (p > 0.05). Therefore, incorporating DSFP in fermented meat production offers a viable alternative to the use of synthetic preservatives.

Evaluation of NO Synthase Activity in Meat-Brining Solutions: Implications for Meat Curing and Color Stability

L-arginine is a substrate for nitric oxide synthase, which, in its optimal conditions in a living organism, generates nitric oxide. In this presented research, we test the hypothesis that nitric oxide can be produced in a solution in which L-arginine, inducible nitric oxide synthase, and meat are present. We evaluate the effect of L-arginine concentration (0.0%/0.1%/0.2%), temperature (20/37 °C), and incubation time (1 h/2 h) on meat color. Nitrite, L-arginine, and citrulline concentrations are analyzed, as well as the UV-Vis and Raman spectra of meat extracts and meat, respectively. The results indicate that there is very weak evidence that at a pH level closer to the enzyme's optimum, slightly higher concentrations of nitrite can be found. The decrease in L-arginine concentration after incubation of an enzyme with meat in water suggests enzyme activity. The UV-Vis and Raman spectra do not support the generation of nitroso myoglobin. Meat color analysis showed lower a* coordinate values in samples incubated with nitric oxide synthase compared to their analogs without the enzyme. The results indicate that in given conditions, nitric oxide synthase cannot be used as a nitrite replacer.

Impact of ultra-processed meat products on human health: Review and outlook

Modern diets are increasingly dominated by ultra-processed foods, a shift driven by urbanization and lifestyle changes. Among these, ultra-processed meat products (UPMPs) are particularly popular due to their appealing flavor and texture. However, emerging evidence highlights potential health risks associated with UPMPs. Although meat products are rich in high-quality proteins, the processing methods used in UPMPs can affect protein digestibility. Moderate processing techniques, such as sous-vide cooking, fermentation, and enzymatic tenderization, can enhance digestion and nutrient absorption, whereas excessive processing may lead to protein aggregation and cross-linking, reducing protein digestibility. Additionally, the overuse of additives and excessive thermal processing are key concerns in UPMP production, leading to the formation of potentially harmful substances, including acrylamide, heterocyclic amines, polycyclic aromatic hydrocarbons, and advanced glycation end products. This review examines how different processing techniques influence protein digestibility in UPMPs, elucidates the pathways through which harmful substances are generated, and assesses the impact of UPMPs on gut health, with a focus on gut microbiota and the colon. Our synthesis of current research indicates that excessive consumption of UPMPs contributes to gut microbiota dysbiosis, compromises the gut barrier, and increases the risk of colorectal cancer, though the dose-dependent effects require further clarification. Future research should focus on key parameters of moderate processing, explore natural alternatives to harmful additives, examine the dose-response relationship between UPMP consumption and health risks, and evaluate how individual factors, such as genetics and metabolism, influence the health impacts of UPMPs.

Surface-Enhanced Raman Spectroscopy for Nitrite Detection

Nitrite is an important chemical intermediate in the nitrogen cycle and is ubiquitously present in environmental and biological systems as a metabolite or additive in the agricultural and food industries. However, nitrite can also be toxic in excessive concentrations. As such, the development of quick, sensitive, and portable assays for its measurement is desirable. In this review, we summarize the working principles and applications of surface-enhanced Raman spectroscopy (SERS) as a rapid, portable, and ultrasensitive method for nitrite detection and showcase its applicability in various water, food, and biological samples. The challenges and opportunities for future developments are also discussed.

Residual Nitrite, Nitrate, and Volatile N-Nitrosamines in Organic and Conventional Ham and Salami Products

Nitrite and nitrate in meat products may be perceived negatively by consumers. These compounds can react to form carcinogenic volatile N-nitrosamines. "Nitrite-free" (i.e., uncured) organic meat products may contain nitrate from natural sources (e.g., spices and water). We studied the quality of ham and salami (conventional cured; organic cured; organic uncured). Residual nitrite and nitrate, volatile N-nitrosamines, microbial load, surface color, water activity, and pH were determined, considering one week of refrigerated storage in open or unopened packages. Residual nitrite and nitrate in organic, uncured salami were similar to cured salami, presumably from the addition of herbs and spices and nitrate reduction by nitrate reductase from microorganisms. For cooked ham, residual nitrite was significantly lower in the organic, uncured sample, while residual nitrate was not detected. N-nitrosodiphenylamine was detected in all samples at day 0, exceeding, in three out of five cured and both uncured products, the US legal limit of 10 µg/kg of volatile N-nitrosamines in foods. This finding warrants further investigation. The microbial load in salami products was dominated by bacteria from starter cultures. In ham, a slight increase in total aerobic count and lactic acid bacteria during storage was noted. Overall, the microbial quality of the products was as expected for the respective product types.

Preparation of ortho-hydroxyl/carboxyl dual-functionalized hypercrosslinked polymers for highly efficient enrichment of nitrosamines with broad polarity prior to gas chromatography-mass spectrometry analysis

N-nitrosamines (NAs) are highly carcinogenic substances commonly detected in food. They demonstrate a broad spectrum of polarity, posing a challenge in finding a suitable adsorbent capable of simultaneously adsorbing and enriching both polar and nonpolar NAs with high extraction recoveries. The present study involves the synthesis of a series of carboxyl functionalized hypercrosslinked polymers, followed by a comparative evaluation of their adsorption performance towards NAs. The results demonstrated that the ortho-hydroxyl/carboxyl dual-functionalized hypercrosslinked polymer (SA-FDA-HCP), synthesized using salicylic acid as the monomer and formaldehyde dimethyl acetal as the crosslinking agent, exhibited significantly enhanced adsorption performance on NAs. The maximum adsorption capacities of SA-FDA-HCP for N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosopyrrolidine, and N-nitrosodiphenylamine were determined to be 1.40, 4.18, 2.84, and 52.4 mg g-1, respectively. These values surpass those reported in the literature for other adsorbents. Furthermore, the polymer exhibited extraction recoveries exceeding 80 % for all four NAs, and it exhibits exceptional selectivity towards NAs. The high adsorption performance can be attributed to the synergistic effects of multiple interactions, including electrostatic, hydrogen bonding and hydrophobic interactions. Based on the synthesized hypercrosslinked polymers, a method for analyzing these NAs was developed using dispersed solid-phase extraction combined with gas chromatography-mass spectrometry. The method demonstrates good accuracy and precision within the linear range of 1 - 80 ng mL-1, while providing relative recoveries for the four NAs range from 91.1 % to 111.5 %. The intra-day and inter-day relative standard deviations are between 4.4 % and 9.8 %, as well as 5.6 % and 10.9 %, respectively. Moreover, the limits of detection fall within a range of 0.11 to 0.73 ng mL-1. These results indicate that the developed material holds great potential for the separation, enrichment and analysis of N-nitrosamines across diverse applications.

Biodegradation of chemical contamination by lactic acid bacteria: A biological tool for food safety

Chemical pollutants such as mycotoxins and pesticides exert harmful effects on human health such as inflammation, oxidative stress, and cancer. Several strategies were applied for food decontamination, including physicochemical and biological strategies. The present review comprehensively discussed the recent efforts related to the biodegradation of eight food chemical contaminants, including mycotoxins, acrylamide, biogenic amines, N-nitrosamines, polycyclic aromatic hydrocarbons, bisphenol A, pesticides, and heavy metals by lactic acid bacteria (LAB). Biological detoxification by LAB such as Lactobacillus is a promising approach to remove the risks related to the presence of chemical and environmental pollutants in foodstuffs. It is a safe, efficient, environmentally friendly, and low-cost strategy to remove hazardous compounds. LAB can directly decrease these chemical pollutants by degradation or adsorption. Also, it can indirectly reduce the content of these pollutants by reducing their precursors. Hence, LAB can contribute to reducing chemical pollutants in contaminated foods and enhance food safety.

Toward "clean label" processed meat using starter culture and beetroot powder: A case-study in restructured cooked ham

This study evaluated the effects of the combination of beet powder, starter culture, and sodium erythorbate as a curing agent on the chemical and microbiological characteristics of restructured cooked ham during cold storage. Five treatments were developed: the positive control group (COP) with the addition of nitrite and sodium erythorbate, negative control treatment (CON) with the addition of sodium erythorbate; ham added with beet powder (AP), ham added with beet powder and starter culture (APC), ham added with beet powder, starter culture, and sodium erythorbate (APCE). The ham's curing properties and oxidative stability were analyzed for 30 days under refrigeration. The APCE treatment showed better conversion of nitrate to nitrite at time 0 (46.6 mg/kg). The COP sample showed higher residual nitrite content at time 0 (73.1 mg/kg) and nitrosohemochrome pigment (35.67 ppm). Combining beet powder with the commercial starter culture and sodium erythorbate in the formulation of restructured cooked hams positively affected the control of lipid and protein oxidation, making it an alternative to commercial sodium nitrite. PRACTICAL APPLICATION: Beetroot and arugula powders are added to the restructured cooked ham to prepare a clean-label meat product without sodium nitrite. The effects of starter culture and sodium erythorbate are also evaluated. .

The metabolic regulation mechanism of gallic acid on biogenic amines and nitrosamines in reduced-nitrite Chinese fermented sausages: A perspective of metabolomics and metagenomics

Reducing nitrites tends to increase the accumulation of hazardous biogenic amines (BAs) in Chinese fermented sausages (CFSs). Gallic acid (GA) has emerged as a potential alternative to reduce nitrite usage and control BAs. This study explored how GA inhibits BAs and nitrosamines accumulation in reduced-nitrite CFSs. Results demonstrated that combining 0.05% (w/w) GA with reduced nitrite effectively curbed BAs and N-nitrosodimethylamine, decreasing total BA from 271.48 to 125.46 mg/kg. Fifty-one metabolites associated with the metabolism of BAs and N-nitrosodimethylamine were identified. GA boosted Lactococcus while reducing spoilage bacteria and Macrococcus. This dual regulation suppressed BAs and dimethylamine accumulation by regulating amino acids and trimethylamine pathways. Consequently, GA achieved an 89.86% reduction in N-nitrosodimethylamine by decreasing the key precursors like putrescine, dimethylamine, and nitrite. These findings offer new insights into utilizing GA and similar plant polyphenols to manage BAs and nitrosamines in meat products with reduced nitrite usage.

Using Celery Powder in a Semi-Dry Fermented Sausage 'Heat-Treated Sucuk': Nitrosamine Formation, Lipid Oxidation, and Volatile Compounds

This study investigated the effect of using celery powder (CP) as source of pre-converted nitrite (treatments: A: 150 mg/kg NaNO2, B: 100 mg/kg NaNO2 + CP as 50 mg/kg NaNO2 equivalent, C: 50 mg/kg NaNO2 + CP as 100 mg/kg NaNO2 equivalent, D: CP as 150 mg/kg NaNO2 equivalent) on the physicochemical and microbiological properties in heat-treated sucuk (HTS), a kind of semi-dry fermented sausage. The influence of cooking time (CT) on the nitrosamine formation in HTS with and without CP was also determined. The results indicated that the use of CP increased the pH value and decreased the aw value. Micrococcus/Staphylococcus and residual nitrite were not affected by the use of CP. TBARS value varied from 0.78 to 0.90 mg MDA/kg. CP did not affect the abundance of hexanal in HTS, however, it increased the abundance of camphene. The results of PCA showed that treatments A, B, and C had similar volatile compound profiles. CP did not affect both N-nitrosodimethylamine and N-nitrosodiethylamine, but their levels increased as the CT increased. Increased CT also resulted in increased N-nitrosopiperidine (NPIP) in all treatments, but the cooking for 1 min did not cause a significant increase in treatments A, B, and C. CP leads to a significant increase in NPIP content, especially after 3 and 5 min of cooking in HTS.

Clean labelling sodium nitrite at pilot scale: In-situ reduction of nitrate from plant sources and its effects on the overall quality and safety of restructured cooked ham

Growing health and environmental concerns have increased demand for all-natural products, with a focus on clean labelling. Sodium nitrite is the most widely used additive in the meat industry because it imparts the typical cured flavour and colour to meat products and, most importantly, their microbiological safety. However, due to health concerns, the European Commission is proposing revised regulations to reduce nitrate and nitrite levels in meat products. As a result, the meat industry is actively seeking alternatives. This study explored the production of four cooked hams utilising nitrate-rich vegetable sources combined with two different nitrate-reducing commercial food cultures, alongside a control ham prepared with sodium nitrite (150 ppm). Microbiological, physico-chemical (pH, water activity, nitrate and nitrite concentration, lipid profile, lipid oxidation) and sensory (texture and colour profile) characterisation of the products was carried out. Challenge tests for Listeria monocytogenes, Clostridium sporogenes and Clostridium perfringens have been performed to assess the growth of pathogens, if present in the products. Results revealed comparable microbiological and physico-chemical profiles across ham formulations, with minor differences observed in colour parameters for sample C. The sensory analysis showed that for the pilot ham formulations A and D, there were no significant differences in consumer perception compared to the control ham. In the challenge tests, L. monocytogenes levels were similar in both control and tested hams. There were no significant differences in C. sporogenes and C. perfringens counts at any temperature or between test and control samples. These results indicate that this technology has a potential future in the cured meat sector, as regulators mandate the reduction of added synthetic chemicals and consumers seek healthier and more natural ingredients in their daily diets.

Investigating the Effects of Pink-Generating Ligands on Enhancing Color Stability and Pigment Properties in Pork Sausage Model Systems Cured with Sodium Nitrite or White Kimchi Powder

In this study, we investigated the effects of different nitrite sources (sodium nitrite or white kimchi powder) and pink-generating ligands (cysteine, histidine, or nicotinamide) on the development and stability of cured meat color in pork sausage model systems over 30 d of refrigerated storage. The samples were prepared in a 2 × 3 factorial design with two nitrite sources and three ligands, and their physicochemical properties were evaluated on days 0, 15, and 30. Although white kimchi powder induced cured color development similar to that of synthetic sodium nitrite, it resulted in higher cooking loss and lower residual nitrite content in cured pork sausages (p < 0.05). The addition of cysteine resulted in significantly higher CIE a* values, cured meat pigment, and curing efficiency than histidine and nicotinamide (p < 0.05), while yielding lower pH values, residual nitrite content, and total pigment content (p < 0.05). The storage duration significantly reduced the residual nitrite and total pigment contents of the products. These findings suggest that white kimchi powder can serve as a natural alternative to sodium nitrite in pork sausage models and that the incorporation of cysteine has a favorable impact on the development and enhancement of cured meat color.

From detection methods to risk prevention: Control of N-nitrosamines in foods and the role of natural bioactive compounds

Food processing unavoidably introduces various risky ingredients that threaten food safety. N-Nitrosamines (NAs) constitute a class of food contaminants, which are considered carcinogenic to humans. According to the compiled information, pretreatment methods based on solid-phase extraction (SPE) were widely used before the determination of volatile NAs in foods. The innovation of adsorbents and hybridization of other methods have been confirmed as the future trends of SPE-based pretreatment methods. Moreover, technologies based on liquid chromatography and gas chromatography were popularly applied for the detection of NAs. Recently, sensor-based methods have garnered increasing attention due to their efficiency and flexibility. More portable sensor-based technologies are recommended for on-site monitoring of NAs in the future. The application of artificial intelligence can facilitate data processing during high-throughput detection of NAs. Natural bioactive compounds have been confirmed to be effective in mitigating NAs in foods through antioxidation, scavenging precursors, and regulating microbial activities. Meanwhile, they exhibit strong protective activities against hepatic damage, pancreatic cancer, and other NA injuries. Further supplementation of data on the bioavailability of bioactives can be achieved through encapsulation and clinical trials. The utilization of bioinformatics tools rooted in various omics technologies is suggested for investigating novel mechanisms and finally broadening their applications in targeted therapies.

Source-specific nitrate intake and all-cause mortality in the Danish Diet, Cancer, and Health Study

INTRODUCTION

Nitrate and nitrite are naturally occurring in both plant- and animal-sourced foods, are used as additives in the processing of meat, and are found in water. There is growing evidence that they exhibit a spectrum of health effects, depending on the dietary source. The aim of the study was to examine source-dependent associations between dietary intakes of nitrate/nitrite and both all-cause and cause-specific mortality.

METHODS

In 52,247 participants of the Danish Diet, Cancer and Health Study, associations between source-dependent nitrate and nitrite intakes--calculated using comprehensive food composition and national drinking water quality monitoring databases--and all-cause, cardiovascular disease (CVD)-related, and cancer-related mortality over 27 years were examined using restricted cubic splines within Cox proportional hazards models adjusting for demographic, lifestyle, and dietary confounders. Analyses were stratified by factors hypothesised to influence the formation of carcinogenic N-nitroso compounds (namely, smoking and dietary intakes of vitamin C, vitamin E, folate, and polyphenols).

RESULTS

Plant-sourced nitrate intake was inversely associated with all-cause mortality [HRQ5vsQ1: 0.83 (0.80, 0.87)] while higher risks of all-cause mortality were seen for higher intakes of naturally occurring animal-sourced nitrate [1.09 (1.04, 1.14)], additive permitted meat-sourced nitrate [1.19 (1.14, 1.25)], and tap water-sourced nitrate [1.19 (1.14, 1.25)]. Similar source-dependent associations were seen for nitrite and for CVD-related and cancer-related mortality except that naturally occurring animal-sourced nitrate and tap water-sourced nitrate were not associated with cancer-related mortality and additive permitted meat-sourced nitrate was not associated with CVD-related mortality. No clear patterns emerged in stratified analyses.

CONCLUSION

Nitrate/nitrite from plant sources are inversely associated while those from naturally occurring animal-sources, additive-permitted meat sources, and tap water-sources are positively associated with mortality.

Fabrication of Highly Sensitive and Selective Nitrite Colorimetric Sensor Based on the Enhanced Peroxidase Mimetic Activity of Using Acetic Acid Capped Zinc Oxide Nanosheets

Nitrite ions (NO2-), as one of the leading type-A inorganic-anion, showing significant-effects in the aquatic environment and also to humans health. Whereas, the higher uptake causes detrimental threat to human health leading to various chronic diseases, thus demanding efficient, reliable and convenient method for its monitoring. For this purpose, in the present research study we have fabricated the mimetic nonozyme like catalyst based colorimetric nitrite sensor. The acetic acid capped Zinc Oxide (ZnO) nanosheets (NSs) were introduce as per-oxidase mimetic like catalyst which shows high efficiency towards the oxidative catalysis of colorless tetramethylbenzidine (TMB) to oxidized-TMB (blue color) in the presence of Hydrogen-peroxide (H2O2). The present nitrite ions will stimulate the as formed oxidized-TMB (TMBox), and will caused diazotization reaction (diazotized-TMBox), which will not only decreases the peak intensity of UV-visible peak of TMBox at 652 nm but will also produces another peak at 446 nm called as diazotized-TMBox peak, proving the catalytic reaction between the nitrite ions and TMBox. Further, the prepared colorimetric sensor exhibits better sensitivity with a wider range of concentration (1 × 10-3-4.50 × 10-1 µM), lowest limit of detection (LOD) of 0.22 ± 0.05 nM and small limit of quantification (LOQ) 0.78 ± 0.05 nM having R2 value of 0.998. Further, the colorimetric sensor also manifest strong selectivity towards NO2- as compared to other interference in drinking water system. Resultantly, the prepared sensor with outstanding repeatability, stability, reproducibility, re-usability and its practicability in real water samples also exploit its diverse applications in food safety supervision and environmental monitoring.

Recent advances in spoilage mechanisms and preservation technologies in beef quality: A review

Beef is a popular meat product that can spoil and lose quality during postharvest handling and storage. This review examines different preservation methods for beef, from conventional techniques like low-temperature preservation, irradiation, vacuum packing, and chemical preservatives, to novel approaches like bacteriocin, essential oil, and non-thermal technologies. It also discusses how these methods work and affect beef quality. The review shows that beef spoilage is mainly due to enzymatic and microbial activities that impact beef freshness, texture, and quality. Although traditional preservation methods can extend beef shelf life, they have some drawbacks and limitations. Therefore, innovative preservation methods have been created and tested to improve beef quality and safety. These methods have promising results and potential applications in the beef industry. However, more research is needed to overcome the challenges and barriers for their commercialization. This review gives a comprehensive and critical overview of the current and emerging preservation methods for beef and their implications for the beef supply chain.

The Potential Substitution of Oyster Shell Powder for Phosphate in Pork Patties Cured with Chinese Cabbage and Radish Powder

The use of natural ingredients in meat processing has recently gained considerable interest, as consumers are increasingly attracted to clean-label meat products. However, limited research has been conducted on the use of natural substitutes for synthetic phosphates in the production of clean-label meat products. Therefore, this study aimed to explore the potential of oyster shell powder as a substitute for synthetic phosphates in pork patties cured with Chinese cabbage or radish powders. Four different groups of patties were prepared using a combination of 0.3% or 0.6% oyster shell powder and 0.4% Chinese cabbage or radish powder, respectively. These were compared with a positive control group that contained added nitrite, phosphate, and ascorbate and a negative control group without these synthetic ingredients. The results showed that patties treated with oyster shell powder had lower (p<0.05) cooking loss, thickness and diameter shrinkage, and lipid oxidation than the negative control but had lower (p<0.05) residual nitrite content and curing efficiency than the positive control. However, the use of 0.6% oyster shell powder adversely affected the curing process, resulting in a decreased curing efficiency. The impact of the vegetable powder types tested in this study on the quality attributes of the cured pork patties was negligible. Consequently, this study suggests that 0.3% oyster shell powder could serve as a suitable replacement for synthetic phosphate in pork patties cured with Chinese cabbage or radish powders. Further research on the microbiological safety and sensory evaluation of clean-label patties during storage is required for practical applications.

Effect of the addition of black garlic on the quality parameters of jerked beef meat with pork

The objective of this work was to evaluate the effects of the replacement of nitrite by natural antioxidants from black garlic (BG) on the quality parameters of jerked beef meat with pork for 60 days. Four formulations were prepared: control, 0.02% of sodium nitrite in brine curing, w/v (CON); 1.5% BG in brine curing, w/v (ASU); 1.5% BG in dry curing, w/w (ASS); and 1.5% of BG in the brine curing, w/v and 1.5% of BG in dry curing, w/w (ASUS). Nutritional composition, pH, water activity, shear force, fatty acid profile, color, and oxidative stability of the formulations were analyzed. The addition of BG did not affect the nutritional composition, pH, water activity, shear force, and fatty acid profile. On the other hand, it resulted in lower weight loss after centrifugation and lower values of L* and a*. TBARS values from the 30th day of storage were lower in the ASUS formulation, while carbonyl compounds at all times were lower than in the CON formulation. Results suggest that BG was an efficient alternative to nitrite in controlling protein oxidation during storage. Thus, the use of pork for the manufacture of jerked beef can be an alternative, and black garlic can be applied as a natural additive to the replacement of nitrite. In addition, black garlic was efficient in improving the oxidative stability of the jerked beef meat with pork.

Water extractability of the zinc protoporphyrin IX-myoglobin complex from Parma ham is pH-dependent

The bright red color of Parma ham is mainly derived from zinc protoporphyrin IX (ZnPP), which exists in both water-soluble and insoluble states. Water-soluble ZnPP mainly binds to hemoglobin, however, the presence of water-insoluble ZnPP remains unexplained. Therefore, we aimed to elucidate how ZnPP exists in a water-insoluble state by focusing on its binding substance. Depending on the skeletal muscle, water-insoluble ZnPP comprised 30-50% of total ZnPP. The ZnPP water extractability was positively correlated with muscle pH. Water-insoluble ZnPP was extractable with a high-pH solution and existed as a complex with myoglobin or hemoglobin; nevertheless, myoglobin-binding ZnPP was more abundant. Furthermore, the water solubility of the myoglobin globin moiety at pH 5.5-6.0 was reduced by ZnPP binding. These results suggest that water-insoluble ZnPP mainly exists as a ZnPP-Mb complex, with low solubility attributed to the low pH of the ham.

Innovative Applications of Tenebrio molitor Larvae in the Production of Sustainable Meat Sausages: Quality and Safety Aspects

With the world's population continuing to grow, ensuring sustainable protein sources for everyone is becoming increasingly challenging. Despite meat being considered unsustainable, people find it challenging to abstain from consuming it. However, one solution to this dilemma could be the incorporation of mealworms into conventional meat products, i.e., sausages. The incorporation of mealworms into sausage formulations appears to shift the fatty acid profile towards higher levels of monounsaturated fats and polyunsaturated fatty acids (PUFAs), particularly omega-3s, potentially enhancing the nutritional value and offering health benefits. Therefore, our study aimed to improve the nutritional value and safety parameters of traditional sausages by enriching them with the flour of mealworm larvae. For this purpose, the larvae were reared on a sustainable substrate with brewery by-products, brewer's yeast, and carrots. They were used frozen and freeze-dried in sausage recipes, replacing pork in different proportions. The analysis of the product's chemical safety parameters (biogenic amines, nitrates and nitrites, volatile fatty acids (FA), and peroxide) and nutritional value (including collagen, cholesterol, amino acids, FA, and hydroxyproline) was carried out in an accredited laboratory. The results of our study have demonstrated that the incorporation of mealworms into sausages, particularly through freeze-drying, increased fat content and enhanced the profile of FA, including omega-3s while reducing protein and cholesterol levels, and altering collagen content, suggesting improved nutritional value and potential health benefits without compromising the safety of the product. Therefore, we are highlighting that the addition of mealworms influences the quality of amino acids positively and maintains biogenic amine levels within safe limits, alongside a negligible impact on nitrates and nitrites and a reduction in peroxide values. These findings indicate an overall improvement in sausage quality and safety without compromising safety.

Strategies for Healthier Meat Foods: An Overview

Functional food products remain the focus of current market trends toward healthier nutrition. The consumption of meat-based functional foods has been a topic of interest in food innovation since some of these products generate controversy due to their possible adverse effects on health. However, studies have demonstrated that meat-based functional products are considered an opportunity to improve the nutritional profile of meat products through the addition of biologically valuable components and to meet the specific needs of consumers. In this sense, some strategies and techniques are applied for processing and developing functional meat products, such as modifying carcass composition through feeding, reformulating meat products, and processing conditions. This review focuses on presenting developed and evaluated strategies that allow the production of healthy and functional meat foods, which application has successfully achieved the sensory, nutritional, and technological parameters mainly affected by such application.

Zinc Protoporphyrin-Rich Pork Liver Homogenates as Coloring Ingredients in Nitrite-Free Liver Pâtés

This study aimed to investigate the coloring ingredient potential of liver homogenates that form Zn protoporphyrin (ZnPP), a natural red pigment, after anaerobic incubation. Liver homogenates were used to develop nitrite-free sterile pork liver pâtés. These homogenates were applied in the formulation of pâtés directly or after centrifugation to obtain a pellet that was highly concentrated in ZnPP. Both the whole homogenate and its insoluble fraction were adjusted to pH 7.5 before their use in the formulation of pâtés with and without antioxidant (0.5% ascorbate plus 0.1% tocopherol) addition. Pâtés formulated with the whole homogenate showed color and texture characteristics that were similar to those of the positive control with nitrite. However, high levels of the insoluble fraction also led to pâtés with improved color characteristics but with a two-fold softened texture. Therefore, the form and amount of ZnPP added played roles in the final appearance of the product. The ZnPP pigment was more stable than heme in the sterilization treatment, and antioxidant addition proved to be unnecessary. The ZnPP-rich ingredients allowed for the preparation of nitrite-free cooked liver pâtés with a stable red color and could thus be potentially applied in other uncured cooked meat products.

Improving quality of poultry and its meat products with probiotics, prebiotics, and phytoextracts

Remarkable changes have occurred in poultry farming and meat processing in recent years, driven by advancements in breeding technology, feed processing technology, farming conditions, and management practices. The incorporation of probiotics, prebiotics, and phytoextracts has made significant contributions to the development of poultry meat products that promote both health and functionality throughout the growth phase and during meat processing. Poultry fed with these substances improve meat quality, while incorporating probiotics, prebiotics, and phytoextracts in poultry processing, as additives or supplements, inhibits pathogens and offers health benefits to consumers. However, it is vital to assess the safety of functional fermented meat products containing these compounds and their potential effects on consumer health. Currently, there's still uncertainty in these aspects. Additionally, research on utilizing next-generation probiotic strains and synergistic combinations of probiotics and prebiotics in poultry meat products is in its early stages. Therefore, further investigation is required to gain a comprehensive understanding of the beneficial effects and safety considerations of these substances in poultry meat products in the future. This review offered a comprehensive overview of the applications of probiotics and prebiotics in poultry farming, focusing on their effects on nutrient utilization, growth efficiency, and gut health. Furthermore, potential of probiotics, prebiotics, and phytoextracts in enhancing poultry meat production was explored for improved health benefits and functionality, and possible issues associated with the use of these substances were discussed. Moreover, the conclusions drawn from this review and potential future perspectives in this field are presented.

Development of a novel hybrid antimicrobial peptide for enhancing antimicrobial spectrum and potency against food-borne pathogens

AIMS

To address the increasingly serious challenge of the transmission of foodbrone pathogens in the food chain.

METHODS AND RESULTS

In this study, we employed rational design strategies, including truncation, amino acid substitution, and heterozygosity, to generate seven engineered peptides with α-helical structure, cationic property, and amphipathic characteristics based on the original Abhisin template. Among them, as the hybird antimicrobial peptide (AMP), AM exhibits exceptional stability, minimal toxicity, as well as broad-spectrum and potent antimicrobial activity against foodborne pathogens. Besides, it was observed that the electrostatic incorporation demonstrates by AM results in its primary targeting and disruption of the cell wall and membrane of Escherichia coli O157: H7 (EHEC) and methicillin-resistant Staphylococcus aureus (MRSA), resulting in membrane perforation and enhanced permeability. Additionally, AM effectively counteracts the deleterious effects of lipopolysaccharide, eradicating biofilms and ultimately inducing the demise of both food spoilage and pathogenic microorganisms.

CONCLUSIONS

The findings highlight the significant potential of AM as a highly promising candidate for a novel food preservative and its great importance in the design and optimization of AMP-related agents.

Selection of lactic acid bacteria as biopreservation agents and optimization of their mode of application for the control of Listeria monocytogenes in ready-to-eat cooked meat products

In order to meet consumers´ demands for more natural foods and to find new methods to control foodborne pathogens in them, research is currently being focused on alternative preservation approaches, such as biopreservation with lactic acid bacteria (LAB). Here, a collection of lactic acid bacteria (LAB) isolates was characterized to identify potential biopreservative agents. Six isolates (one Lactococcus lactis, one Lacticaseibacillus paracasei and four Lactiplantibacillus plantarum) were selected based on their antimicrobial activity in in vitro assays. Whole genome sequencing showed that none of the six LAB isolates carried known virulence factors or acquired antimicrobial resistance genes, and that the L. lactis isolate was potentially a nisin Z producer. Growth of L. monocytogenes was successfully limited by L. lactis ULE383, L. paracasei ULE721 and L. plantarum ULE1599 throughout the shelf-life of cooked ham, meatloaf and roasted pork shoulder. These LAB isolates were also applied individually or as a cocktail at different inoculum concentrations (4, 6 and 8 log10 CFU/g) in challenge test studies involving cooked ham, showing a stronger anti-Listerial activity when a cocktail was used at 8 log10 CFU/g. Thus, a reduction of up to ~5.0 log10 CFU/g in L. monocytogenes growth potential was attained in cooked ham packaged under vacuum, modified atmosphere packaging or vacuum followed by high pressure processing (HPP). Only minor changes in color and texture were induced, although there was a significant acidification of the product when the LAB cultures were applied. Remarkably, this acidification was delayed when HPP was applied to the LAB inoculated batches. Metataxonomic analyses showed that the LAB cocktail was able to grow in the cooked ham and outcompete the indigenous microbiota, including spoilage microorganisms such as Brochothrix. Moreover, none of the batches were considered unacceptable in a sensory evaluation. Overall, this study shows the favourable antilisterial activity of the cocktail of LAB employed, with the combination of HPP and LAB achieving a complete inhibition of the pathogen with no detrimental effects in physico-chemical or sensorial evaluations, highlighting the usefulness of biopreservation approaches involving LAB for enhancing the safety of cooked meat products.

From nitrate to NO: potential effects of nitrate-reducing bacteria on systemic health and disease

Current research has described improving multisystem disease and organ function through dietary nitrate (DN) supplementation. They have provided some evidence that these floras with nitrate (NO3-) reductase are mediators of the underlying mechanism. Symbiotic bacteria with nitrate reductase activity (NRA) are found in the human digestive tract, including the mouth, esophagus and gastrointestinal tract (GT). Nitrate in food can be converted to nitrite under the tongue or in the stomach by these symbiotic bacteria. Then, nitrite is transformed to nitric oxide (NO) by non-enzymatic synthesis. NO is currently recognized as a potent bioactive agent with biological activities, such as vasodilation, regulation of cardiomyocyte function, neurotransmission, suppression of platelet agglutination, and prevention of vascular smooth muscle cell proliferation. NO also can be produced through the conventional L-arginine-NO synthase (L-NOS) pathway, whereas endogenous NO production by L-arginine is inhibited under hypoxia-ischemia or disease conditions. In contrast, exogenous NO3-/NO2-/NO activity is enhanced and becomes a practical supplemental pathway for NO in the body, playing an essential role in various physiological activities. Moreover, many diseases (such as metabolic or geriatric diseases) are primarily associated with disorders of endogenous NO synthesis, and NO generation from the exogenous NO3-/NO2-/NO route can partially alleviate the disease progression. The imbalance of NO in the body may be one of the potential mechanisms of disease development. Therefore, the impact of these floras with nitrate reductase on host systemic health through exogenous NO3-/NO2-/NO pathway production of NO or direct regulation of floras ecological balance is essential (e.g., regulation of body homeostasis, amelioration of diseases, etc.). This review summarizes the bacteria with nitrate reductase in humans, emphasizing the relationship between the metabolic processes of this microflora and host systemic health and disease. The potential effects of nitrate reduction bacteria on human health and disease were also highlighted in disease models from different human systems, including digestive, cardiovascular, endocrine, nervous, respiratory, and urinary systems, providing innovative ideas for future disease diagnosis and treatment based on nitrate reduction bacteria.

Jabuticaba peel extract and nisin: A promising combination for reducing sodium nitrite in Bologna-type sausages

This study investigated the effect of a 50% reduction in sodium nitrite and the addition of nisin (200 mg/kg) and different concentrations (0, 0.5%, 0.75%, and 1%) of jabuticaba peel extract (JPE) on the main attributes affected by this chemical additive in Bologna-type sausages. The modified treatments showed approximately 50% lower residual nitrite than the control throughout the storage (60 days at 4 °C). The proposed reformulation did not affect the color (L*, a*, and b*), and the ΔE values (< 2) demonstrated high color stability during storage. Physicochemical (TBARS and volatile compounds) and sensory analyses performed to evaluate oxidative stability indicated that JPE exhibited antioxidant activity comparable to sodium nitrite. The microbiological quality of the reformulated products was similar to the control, but further studies should be conducted to assess the effect of this reformulation strategy on the growth of pathogenic microorganisms impacted by nitrite.

Theoretical estimation of nitrates and nitrites intake from food additives by the Brazilian population

Sodium and potassium nitrates and nitrites are preservatives widely used in meat products and some cheese. They are important toxicologically but there is a lack of data on the exposure of the Brazilian population to these additives. This study aimed to verify the frequency of the use of nitrates and nitrites in processed foods in Brazil and to estimate their theoretical intake by the Brazilian population. A database was built of supermarket products containing nitrates, nitrites, and antioxidants. The Theoretical Maximum Daily Intake (TMDI) and TMDI balanced by the prevalence of food consumption (TMDI BPFC) were determined using consumption data from the Household Budget Surveys (2008/2009 and 2017/2018). The TMDI for nitrates and nitrites was lower than the Acceptable Daily Intake (ADI) for all population groups. Considering the prevalence of food consumption (consumers only), the TMDI BPFC values were lower than the ADI for nitrates (between 0.4 and 0.9 times the ADI) but very high values were obtained for nitrites (between 10 and 24 times the ADI). Our results suggest that the Brazilian population, especially some population groups, may be consuming unsafe amounts of nitrite. As a consequence, their health may be at risk.

Inactivation of Foodborne Pathogens by Lactiplantibacillus Strains during Meat Fermentation: Kinetics and Mathematical Modelling

This study examined the effect of beef fermentation with Lactiplantibacillus paraplantarum (L) PTCC 1965, Lactiplantibacillus (L) plantarum subsp. plantarum PTCC 1745, and Lactiplantibacillus (L) pentosus PTCC 1872 bacteria on the growth of pathogenic bacteria, including Salmonella (S) Typhi PTCC 1609 and Staphylococcus (S) aureus PTCC 1826. The growth of lactic acid bacteria (LAB) and the effect of fermentation on pathogenic bacteria were studied using Weibull: biphasic linear and competitive models. The results showed that the rate of pH reduction was lower in the early stages and increased as the microbial population grew. The α parameter was lower for L. plantarum subsp. plantarum compared to L. paraplantarum and L. pentosus. The comparison of the α parameter for bacterial growth and pH data showed that the time interval required to initiate the rapid growth phase of the bacteria was much shorter than that for the rapid pH reduction phase. The pH value had a 50% greater effect on the inactivation of S. Typhi when compared to the samples containing L. plantarum subsp. plantarum and L. pentosus. The same parameter was reported to be 72% for the inactivation of St. aureus. In general, during the fermentation process, LAB strains caused a decrease in pH, and as a result, reduced the growth of pathogens, which improves consumer health and increases the food safety of fermented meat.

Novel Approaches to Improve Meat Products' Healthy Characteristics: A Review on Lipids, Salts, and Nitrites

Meat products are a staple of many diets around the world, but they have been subject to criticism due to their potential negative impact on human health. In recent years, there has been a growing interest in developing novel approaches to improve the healthy characteristics of meat products, with a particular focus on reducing the levels of harmful salts, lipids, and nitrites. This review aims to provide an overview of the latest research on the various methods being developed to address these issues, including the use of alternative salts, lipid-reducing techniques, and natural nitrite alternatives. By exploring these innovative approaches, we can gain a better understanding of the potential for improving the nutritional value of meat products, while also meeting the demands of consumers who are increasingly concerned about their health and well-being.

Novel strategies for controlling nitrite content in prepared dishes: Current status, potential benefits, limitations and future challenges

Sodium nitrite is commonly used as a multifunctional curing ingredient in the processing of prepared dishes, especially meat products, to impart unique color, flavor and to prolong the shelf life of such products. However, the use of sodium nitrite in the meat industry has been controversial due to potential health risks. Finding suitable substitutes for sodium nitrite and controlling nitrite residue have been a major challenge faced by the meat processing industry. This paper summarizes possible factors affecting the variation of nitrite content in the processing of prepared dishes. New strategies for controlling nitrite residues in meat dishes, including natural pre-converted nitrite, plant extracts, irradiation, non-thermal plasma and high hydrostatic pressure (HHP), are discussed in detail. The advantages and limitations of these strategies are also summarized. Raw materials, cooking techniques, packaging methods, and storage conditions all affect the content of nitrite in the prepared dishes. The use of vegetable pre-conversion nitrite and the addition of plant extracts can help reduce nitrite residues in meat products and meet the consumer demand for clean labeled meat products. Atmospheric pressure plasma, as a non-thermal pasteurization and curing process, is a promising meat processing technology. HHP has good bactericidal effect and is suitable for hurdle technology to limit the amount of sodium nitrite added. This review is intended to provide insights for the control of nitrite in the modern production of prepared dishes.

Influence of Multi-Frequency Ultrasound Treatment on Conformational Characteristics of Beef Myofibrillar Proteins with Different Degrees of Doneness

This study evaluated the effect of multi-frequency sonication (20 kHz, 25 kHz, 28 kHz, 40 kHz, 50 kHz) on structural characteristics of beef myofibrillar proteins (MPs) with different degrees of doneness (Rare 52~55 °C, Medium Rare 55~60 °C, Medium 60~65 °C, Medium Well 65~69 °C, Well Down 70~80 °C, and Overcooked 90 °C). The results showed that surface hydrophobicity and sulfhydryl content increased with the increase in degree of doneness. At the same degree of doneness, the sulfhydryl group contents reached the maximum at a frequency of 28 kHz. In addition, the absolute value of ζ-potential was significantly decreased after ultrasonic treatment (p < 0.05). SDS gel electrophoresis showed that the bands of beef MPs were not significantly affected by various ultrasonic frequencies, but the bands became thinner when the degree of doneness reached overcooked. Fourier transform infrared spectrum showed that with the increase of ultrasonic frequency, α-helix content decreased, and random coil content significantly increased (p < 0.05). The results of atomic force microscopy indicated that the surface structure of beef MPs was damaged, and the roughness decreased by sonication, while the roughness significantly increased when the degree of doneness changed from medium to overripe (p < 0.05). In conclusion, multi-ultrasound combined with degree of doneness treatment alters the structural characteristics of beef MPs.

Analysis of Quality and Color Properties according to the Gas Composition (Modified Atmosphere Packaging) of Pork Sous-Vide Ham Preserved in Natural Brine

The purpose of this study was to analyze whether seawater has positive effects on appearance characteristics, such as CIE a*, and to determine the gas composition concentration that is suitable for maintaining it. Pork hind meat was cured with four types of curing agent for 5 d at 4°C. The different curing agents comprised the control salt, control nitrite pickling salt (CN), treatment brine, and treatment bittern (BT). The cured hams were cooked at 65°C for 4 h and packaged at O₂:N₂ gas ratios of 7:3, 8:2, and 9:1 for 3 wk. The physicochemical properties were assessed immediately after heating the sample, and the color properties were measured after a 3 wk storage period. Based on the correlation results of the physicochemical properties, BT had a higher curing and cooking yield than the other treatments, owing to its high salinity. Results of color properties for BT (7:3) and CN (8:2) showed similar color CIE L*, CIE a* chroma, and hue angle values. Therefore, BT can be said to be a sous-vide curing agent suitable for preserving the color of ham, and a high nitrogen concentration of 30% helps to maintain the appearance of seawater sous-vide ham.

Novel Ag-coated nanofibers prepared by electrospraying as a SERS platform for ultrasensitive and selective detection of nitrite in food

Nitrite is commonly used as a preservative and color fixative in the meat industry. However, the risk of it transforming into N-nitrosamine restricts its intake. Herein, a novel sensitive Ag-coated nanofiber surface-enhanced Raman scattering (SERS) platform was developed for rapid nitrite detection. The electrospraying technique was firstly used to assemble Ag nanoparticles (NPs) on the nanofibers to obtaine SERS platform. The homogeneity and long-term stability of the SERS platform were evaluated. The limit of detection (LOD) of the SERS platform was estimated to be 2.216 × 10^-12 mol/L, corresponding to 15.29 ng·L^-1 and good linearity was shown between the relative SERS intensity and nitrite concentration range of 10-1 to 10^-4 mol/L. The Ag-coated nanofiber SERS platform was utilized to assay-five common nitrite foods, and the results provided valid evidence for the compatibility of SERS platform in quantitative nitrite detection.

A novel edible colorant lake prepared with CaCO3 and Monascus pigments: Lake characterization and mechanism study

Monascus pigments (MPs) were adsorbed using calcium carbonate to produce CaCO₃-MPs lakes. The fundamental properties and formation mechanism of the lakes were investigated. Results indicated that CaCO₃ displayed a high enough affinity for the MPs to form colorant lakes, while the MPs tended to transform the CaCO₃ crystals from calcite to vaterite. The adsorption of MPs by CaCO₃ followed the Freundlich isothermal model with n value higher than 1, confirming it as physical adsorption. The ΔG⁰ (-29 to ∼-33 kJ/mol) and ΔH⁰(30-55 kJ/mol) indicated that lake formation was a spontaneous and endothermic process. UV/Vis spectroscopic analysis verified the complex formation between Ca²⁺ and MPs via physical bonding, suggesting a possible attraction between the Ca²⁺ and glutamate residues of the MPs. EDS showed that the MPs were trapped inside the particles. FTIR spectroscopy and XPS further confirmed that the physical bonding was the primary driving force behind the lake formation.

Utilization of Porcine Livers through the Formation of Zn-Protoporphyrin Pigment Optimized by a Response Surface Methodology

There is a growing demand for clean-label products. This study aimed to obtain a food-grade coloring ingredient for meat products based on the formation of Zn-protoporphyrin from porcine livers, thus contributing to the development of nitrite-free products. First, the effects of sodium disulfite and acetic, ascorbic, and lactic acids on the formation of Zn-protoporphyrin and the total microbial count were studied. The combination of ascorbic and acetic acids resulted in a higher Zn-protoporphyrin content than acetic acid alone, and microbial levels were maintained (ca. 3 log CFU/mL). Second, a response surface methodology was used to maximize Zn-protoporphyrin while maintaining microbiological food standards. To that end, the effects of pH (4.2-5.4), incubation time (3-30 h), and temperature (25-50 °C) were studied. The selected conditions for Zn-protoporphyrin formation involved anaerobic incubation at pH 4.8 and 45 °C for 24 h. The safety was validated through challenge testing for relevant pathogens (Listeria monocytogenes, Salmonella spp., and Clostridium perfringens). A significant reduction (>6 log units) was observed in the selected conditions for L. monocytogenes and Salmonella, whereas C. perfringens spores remained at the inoculated levels. The optimized procedure is proven to be microbiologically safe, and may improve the color of nitrite-free meat products.

Effects of natural nitrite sources from arugula and barberry extract on quality characteristic of heat-treated fermented sausages

This study was designed to compare the effects of natural nitrite sources from the arugula leaves (arugula extract and pre-converted arugula extract) and the use of barberry extract (BE) in heat-treated fermented sausage formulations. Eight different sausages were manufactured as follows: pre-converted arugula extract (PA), arugula extract (A), pre-converted arugula extract + BE (PAB), arugula extract + BE (AB), nitrite +BE (POB), no nitrite+ BE (NEB), also positive and negative control groups were prepared with (POC) or without nitrite (NEC). The addition of arugula and barberry extracts reduced the residual nitrite content, in fact PAB had the lowest value with a reduction ratio of 47%. The addition of BE lowered the lipid oxidation compared to other counterparts. The use of arugula extract or pre-converted arugula extract resulted in a lower carbonylation than nitrite free samples. The use of natural extracts lowered the a* and b* values compared to control. At the end of the storage, no differences were observed on the overall acceptability of all samples. Combined use of barberry extract with arugula and pre-converted arugula extracts could be used as alternative novel curing agent in heat-treated fermented sausages.

Research Progress of Nitrite Metabolism in Fermented Meat Products

Nitrite is a common color and flavor enhancer in fermented meat products, but its secondary amines may transfer to the carcinogen N-nitrosamines. This review focuses on the sources, degradation, limitations, and alteration techniques of nitrite. The transition among NO3− and NO2−, NH4+, and N2 constitutes the balance of nitrogen. Exogenous addition is the most common source of nitrite in fermented meat products, but it can also be produced by contamination and endogenous microbial synthesis. While nitrite is degraded by acids, enzymes, and other metabolites produced by lactic acid bacteria (LAB), four nitrite reductase enzymes play a leading role. At a deeper level, nitrite metabolism is primarily regulated by the genes found in these bacteria. By incorporating antioxidants, chromogenic agents, bacteriostats, LAB, or non-thermal plasma sterilization, the amount of nitrite supplied can be decreased, or even eliminated. Finally, the aim of producing low-nitrite fermented meat products is expected to be achieved.

Combined Effect of Acid Whey Addition and Ultrasonic Treatment on the Chemical and Microbiological Stability of Lamb Stuffing

The microbiological and chemical stability of stuffing is crucial in meat processing. Small ruminant (lamb) meat has many nutritional advantages (fatty acid composition and ratio, high biological value of protein, source of zinc, and selenium) but is poorly utilized in processing. In this experiment, we determined the effects of physical (sonication), chemical (salt, curing salt, and air access), and microbiological (acid whey) factors on the microbiological and chemical stability of lamb meat stuffing. Proximate composition and fatty acids profile, pH, water activity, lipid oxidation, color parameters, and microbiology examinations were performed in fresh meat stuffing and on the fifth day of refrigerated storage. Ultrasound treatment of the meat with whey reduced its acidity and increased the oxidative stability of fats but did not modify the water activity and color of the stuffing. Stuffing sonication did not affect the growth of LAB but reduced the number of Entereobacteriace, especially in the presence of whey and salt. The treatment of lamb meat stuffing with low-frequency and medium-intensity ultrasound assisted by the addition of acid whey and salt is a technique conducive to reducing the use of nitrates in meat technology and their consumption by consumers.

Development and Innovation in Cooked Ham Produced in Spain

The production of cooked ham has been gaining popularity in recent years in Spain. In general, the production process carried out by the companies remains traditional, and different production methods are therefore being sought to innovate and improve the quality of the product. This is either through pig crossbreeding, varying additives and ingredients, improving some stages of the production process, or providing nutritional and health claims that are useful to guiding the purchasing decision of consumers. Obviously, this series of changes must be subject to Spanish and European regulations in order to be marketed inside and outside the country.

Investigation on the Contents of Nε-carboxymethyllysine, Nε-carboxyethyllysine, and N-nitrosamines in Commercial Sausages on the Chinese Market

Sausages are among the most popular meat products worldwide. However, some harmful products, such as advanced glycation end-products (AGEs) and N-nitrosamines (NAs), can be formed simultaneously during sausage processing. In this study, the contents of AGEs, NAs, α-dicarbonyls and the proximate composition were investigated in two kinds of commercial sausages (fermented sausages and cooked sausages) in the Chinese market. The correlations among them were further analyzed. The results showed that the fermented and cooked sausages had different in protein/fat contents and pH/thiobarbituric acid reactive substance values due to their different processing technologies and added ingredients. The N^ε-carboxymethyllysine (CML) and N^ε-carboxyethyllysine (CEL) concentrations varied from 3.67 to 46.11 mg/kg and from 5.89 to 52.32 mg/kg, respectively, and the NAs concentrations ranged from 1.35 to 15.88 µg/kg. The contents of some hazardous compounds, such as CML, N-nitrosodimethylamine, and N-nitrosopiperidine, were observed to be higher in the fermented sausages than in the cooked sausages. Moreover, levels of NAs in some sausage samples exceeded the limit of 10 µg/kg issued by the United States Department of Agriculture, suggesting that particular attention should be paid to mitigating NAs, especially in fermented sausages. The correlation analysis suggested that the levels of AGEs and NAs were not significantly correlated in both kinds of sausages.

A Review on the Role of Lactic Acid Bacteria in the Formation and Reduction of Volatile Nitrosamines in Fermented Sausages

Nitrosamines are N-nitroso compounds with carcinogenic, mutagenic and teratogenic properties. These compounds could be found at certain levels in fermented sausages. Fermented sausages are considered to be a suitable environment for nitrosamine formation due to acid formation and reactions such as proteolysis and lipolysis during ripening. However, lactic acid bacteria (spontaneous or starter culture), which constitute the dominant microbiota, contribute significantly to nitrosamine reduction by reducing the amount of residual nitrite through nitrite degradation, and pH decrease has an important effect on the residual nitrite amount as well. These bacteria also play an indirect role in nitrosamine reduction by suppressing the growth of bacteria that form precursors such as biogenic amines. In recent years, research interest has focused on the degradation or metabolization of nitrosamines by lactic acid bacteria. The mechanism by which these effects are seen has not been fully understood yet. In this study, the roles of lactic acid bacteria on nitrosamine formation and their indirect or direct effects on reduction of volatile nitrosamines are discussed.

Regulatory Experiences with Root Causes and Risk Factors for Nitrosamine Impurities in Pharmaceuticals

N-Nitrosamines (also referred to as nitrosamines) are a class of substances, many of which are highly potent mutagenic agents which have been classified as probable human carcinogens. Nitrosamine impurities have been a concern within the pharmaceutical industry and by regulatory authorities worldwide since June 2018, when regulators were informed of the presence of N-nitrosodimethylamine (NDMA) in the angiotensin-II receptor blocker (ARB) medicine, valsartan.  Since that time, regulatory authorities have collaborated to share information and knowledge on issues related to nitrosamines with a goal of promoting convergence on technical issues and reducing and mitigating patient exposure to harmful nitrosamine impurities in human drug products. This paper shares current scientific information from a quality perspective on risk factors and potential root causes for nitrosamine impurities, as well as recommendations for risk mitigation and control strategies.

Bacterial nitric oxide synthase in colorizing meat products: Current development and future directions

Nitrite has been widely used in meat products for its abilities including color formation, antimicrobial properties, flavor formation and preventing lipid oxidation. However, the possible generation of N-nitrosamines through reaction of nitrite with secondary amines arises many concerns in the usage of nitrite. For a long time, nitrite substitution is unsettled issue in the meat industry. Many attempts have been tried, however, the alternative solutions are often ephemeral and palliative. In recent years, bacterial nitric oxide synthase (bNOS) has received attention for its critical roles, especially in reddening meat products. This comprehensive background study summarizes the application of bNOS in colorizing meat products, its functions in bacteria, and methods of regulating the bNOS pathway. Based on this information, some strategies for promoting the nitric oxide yield for effectively substituting nitrite are presented, such as changing the environmental conditions for bacterial survival and adding substrate. Thus, bNOS is a promising nitrite substitute for color formation, and further research on its other roles in meat needs to be carried out to obtain the complete picture.