Evaluation of coloration, nitrite residue and antioxidant capacity of theaflavins, tea polyphenols in cured sausage

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.

Formation of advanced glycation end-products and N-nitrosamines in salami of different recipes and fermented at different stages

Most research on the formation of advanced glycation end-products (AGEs) and N-nitrosamines (NAs) in meat products has focused on high-temperature processing. The effects of low-temperature processing on AGEs and NAs formation have rarely been studied. This study investigated the effects of salt addition (0 %, 2 %, and 4 %) and lean-to-fat ratio (10:0, 8:2, and 6:4) on the formation of AGEs and NAs in Salami. We found that the salt in Salami would inhibit CEL formation. And the Lean pork Salami showed the highest Nε-carboxyethyllysine (CEL) and lowest Nε-carboxymethyllysine (CML) contents. For NAs content, it was lowest in Salami with 40 % fat. Principal component analysis and correlation analysis revealed significant correlations between CEL and N-nitrosodiphenylamine (NDPhA) formation in Salami. Additionally, the production of CML was correlated with the extent of fat oxidation, while CEL formation was more strongly associated with protein-related reactions. Furthermore, NAs formation correlated with protein content and protein oxidation.

Micronized olive pomace: A sustainable and innovative strategy to improve the oxidative stability of omega-3 enriched salamis

This study explored the potential of Micronized Olive Pomace (MOP) to improve the oxidative stability of omega-3-enriched salamis while also offering a thorough examination of their technological, microbiological, and nutritional properties. Linseed oil gels containing different concentrations of MOP (0 %, 5 %, 10 %, and 15 %) were prepared and used to replace 30 % of the animal fat in salami, resulting in final MOP concentrations of 0 % (MOP0%), 0.3 % (MOP0.3%), 0.6 % (MOP0.6%), and 0.9 % (MOP0.9%) in the meat mass. The lipid reformulation did not negatively affect the salami ripening. The fat content of the reformulated treatments was reduced by 6.8 % to 8.1 %, compared to the control, which had 30.7 % fat, while the reformulated treatments contained between 28.2 % and 28.6 % fat. Additionally, the levels of alpha-linolenic acid increased from 0.28 to 1.61-2.23 g/100 g of sample. MOP significantly mitigated the increase in lipid oxidation caused by the inclusion of n-3 PUFAs, particularly in the MOP0.9% treatment, which showed a 48 % reduction in TBARS values compared to the MOP0% sample and only a 12 % increase compared to the control after 90 days of storage. This treatment showed a pronounced presence of beneficial volatile compounds from carbohydrate fermentation and amino acid catabolism. It also demonstrated the highest color stability during storage, evidenced by the lowest ΔE values. Thus, this study demonstrated the potential of MOP as an innovative ingredient to enhance the oxidative stability of meat products enriched with n-3 PUFAs, responding to a critical demand in the meat industry for healthier and more sustainable foods.

Electrospinning zein with theaflavin: Production, characterization, and application in active packaging for cold-fresh pork

The interest and demand for active food packaging made from all natural materials have increased significantly, driven by the intent to minimize the ecological impact. Green electrospinning from biopolymers with antimicrobial compounds is considered an ideal candidate for constructing ultrathin, excellent performance, and effective antibacterial fibrous films (FFs). Here, a green electrospinning from zein (Z) ethanol-aqueous solution with varied theaflavin (TF) concentrations (0.6-4 %) was utilized as active packaging for cold-fresh pork. All the Z/TF composite fibrous films (ZTF-FFs) exhibited smooth and uniform surfaces, and their average fiber diameter increased from 484 nm to 705 nm with higher TF concentration. TF addition altered the secondary and crystalline structure of Z-FF, evidenced by Fourier-transform infrared spectroscopy and X-ray diffraction. At 1 % TF addition, ZTF1-FF displayed enhanced thermodynamic stability, with a decomposition residue of 13.88 % and a maximum mass loss rate temperature of 313.45 °C. ZTF1-FF also exhibited excellent hydrophobicity, superior mechanical properties, and significant antibacterial activity against S. aureus and S. paratyphi B. When used for active packaging of cold-fresh pork, ZTF1-FF significantly delayed the increases in total volatile basic nitrogen, total viable count, pH, weight loss, and thiobarbituric acid reactive substances of the pork. Overall, ZTF1-FF showed the most promising potential as an active food packaging material, particularly for preserving cold-fresh meat.

Research Progress on the Mechanism of the Impact of Myofibrillar Protein Oxidation on the Flavor of Meat Products

Myofibrillar proteins primarily consist of myosin, actin, myogenin, and actomyosin. These proteins form complex networks within muscle fibers and are crucial to the physical and chemical properties of meat. Additionally, myofibrillar proteins serve as significant substrates for the adsorption of volatile flavor compounds, including aldehydes, alcohols, ketones, and sulfur and nitrogen compounds, which contribute to the overall flavor profile of meat products. A series of chemical reactions occur during the processing, storage, and transportation of meat products. Oxidation is one of the most significant reactions. Oxidative modification can alter the physical and chemical properties of proteins, ultimately impacting the sensory quality of meat products, including flavor, taste, and color. In recent years, considerable attention has been focused on the effects of protein oxidation on meat quality and its regulation. This study investigates the impact of myofibrillar protein oxidation on the sensory attributes of meat products by analyzing the oxidation processes and the factors that initiate myofibrillar protein oxidation. Additionally, it explores the control of myofibrillar protein oxidation and its implications on the sensory properties of meat products, providing theoretical insights relevant to meat processing methods and quality control procedures.

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.

Quality analysis of steamed beef with black tea and the mechanism of action of main active ingredients of black tea on myofibrillar protein

In this study, we analyzed the tea polyphenol composition, volatile flavor composition and storage stability of steamed beef with black tea. The molecular docking and dynamics were used to elucidate the interaction mechanism between the active components of black tea and myofibrillar proteins. The highest content of caffeine (CAF) was found in black tea steamed beef products, followed by catechin (C), epicatechin gallate (ECG), epicatechin gallate (EGCG) and theaflavins (TF). Steamed beef with black tea showed low ΔE* value, low TBARS value, low carbonyl content as well as high sulfhydryl content during storage. The addition of C, CAF, ECG, EGCG and TF enhanced the oxidative stability of myofibrillar protein. In this study, the effects of active components of black tea on the oxidative stability of myofibrillar protein and their interactions were determined, which could provide a reference for the application of black tea and its active components in meat products. At the same time, it can provide new ideas for the development of new meat products.

N-Nitrosamines: a potential hazard in processed meat products

Nitrite, nitrate, and their salts are added to processed meat products to improve color, flavor, and shelf life and to lower the microbial burden. N-Nitrosamine compounds are formed when nitrosing agents (such as secondary nitrosamines) in meat products interact with nitrites and nitrates that have been added to the meat. With the consumption of such meat products, nitrosation reactions occur in the human body and N-nitrosamine formation occurs in the gastrointestinal tract. Despite the benefits nitrites and nitrates have on food, their tendency to create nitrosamines and an increase in the body's nitrous amine load presents health risks. The inclusion of nitrosamine compounds in possible and probable carcinogen classes according to the International Agency for Research on Cancer requires a re-examination of the literature review on processed meat products. This article evaluates the connections between various cancer types and nitrosamines found in processed meat products. © 2023 Society of Chemical Industry.

Inhibitory effects and reactions of gallic acid, catechin, and procyanidin B2 with nitrosation under stomach simulating conditions

Nitrite widely exists in meat products, and has the functions of bacteriostasis, antisepsis, and color development. However, in an acidic environment, nitrite will react with amines, and further generate nitrosamines with carcinogenic and teratogenic effects. Polyphenols have good antioxidant and nitrite-scavenging effects. This study aimed to evaluate the inhibitory effects of gallic acid, catechin, and procyanidin B2 on the nitrosation reaction under stomach simulating conditions and discuss the potential inhibitory mechanism. The nitrite scavenging rate and nitrosamine synthesis blocking rate of gallic acid, catechin, and procyanidin B2 under different reaction times and contents was determined by UV-vis spectrophotometry. The possible products of the reaction of the three polyphenols with nitrite were analyzed by high-performance liquid chromatography-mass spectrometry (HPLC-MS) to reveal the mechanism of inhibiting nitrification. The results showed that the scavenging rate of the three polyphenols on nitrite and the blocking rate of nitrosamine synthesis increased with the increase of the content and reaction time. The ability of the three polyphenols to inhibit nitrosation was catechin > procyanidin B2 > gallic acid. HPLC-MS analysis showed that under simulated gastric juice conditions, the three phenolics were oxidized by nitrous acid to form their semiquinone radicals as the intermediates and nitrosated derivatives, while nitrite might be converted to ˙NO. These results suggested that gallic acid, catechin, and procyanidin B2 could inhibit nitrosation reactions in an acidic environment and may be used as food additives to reduce nitrite residues and nitrosamines in food.

A Comprehensive Review of Cured Meat Products in the Irish Market: Opportunities for Reformulation and Processing

Cured meat products constitute one of the meat categories commonly consumed in Ireland and has been part of the Irish cuisine and diet for many years. Ham, gammon, and bacon are some of the products that involve curing as part of the traditional processing methods. Common among these products are high levels of salt and the addition of nitrites. These products undergo processing treatments to create variety, preserve shelf-life, and develop their unique quality and safety characteristics. However, consumers are becoming more conscious of the level of processing involved in these products, and the effects of some components and ingredients might be perceived as unhealthy. Meat product developers have been exploring ways to reduce the amount of ingredients such as salt, saturated fat, and chemical preservatives (e.g., nitrites), which are linked to health concerns. This is a challenging task as these ingredients play an important techno-functional role in the products' quality, safety, and identity. While innovative processing techniques are being introduced and progress has been made in reformulation and packaging technologies, much is still unknown, especially regarding the applicability of many of the proposed interventions to a wide range of meat products and their sustainability at the industrial scale.

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.

Antibacterial Effects of Theaflavins against Staphylococcus aureus and Salmonella paratyphi B: Role of Environmental Factors and Food Matrices

This study aimed to investigate the effects of different environmental factors (temperature, pH, and NaCl) and food matrices (skimmed milk powder, lecithin, and sucrose) on the antibacterial activity of theaflavins (TFs) against Staphylococcus aureus (S. aureus) and Salmonella paratyphi B (S. paratyphi B). TFs showed a larger diameter of inhibition zone (DIZ, 12.58 ± 0.09 mm-16.36 ± 0.12 mm) value against S. aureus than that of S. paratyphi B (12.42 ± 0.43 mm-15.81 ± 0.24 mm) at the same concentration (2-10 mg/mL). When temperatures were 25-121 °C, the DIZ of TFs against both S. aureus and S. paratyphi B was not significantly different. As pH increased from 2 to 10, their DIZ values decreased significantly from 16.78 ± 0.23 mm to 13.43 ± 0.08 mm and 15.63 ± 0.42 mm to 12.18 ± 0.14 mm, respectively. Their DIZ values increased slightly as the NaCl concentration increased from 0.2 mol/L to 0.8 mol/L, while their DIZ values decreased significantly for skimmed milk powder concentrations in the range of 20-120 g/L. Regarding the concentrations of lecithin and sucrose were 2-12 g/L and 10-60 g/L, their DIZ values showed no significant change against S. paratyphi B, but an increased trend for S. aureus. Under the above different environmental factors and food matrices, TFs maintained excellent antibacterial activity against S. aureus and S. paratyphi B, providing a theoretical guidance for applying TFs as novel antibacterial additives in the food industry.

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.

Effect of Cold-Plasma-Treated Phosphate Solution to Substitute Partial Nitrite on the Color, Texture, and Flavor of Smoked Sausage

There are several alternative technologies to nitrite use in meat products, including cold plasma. In this study, a cold-plasma-treated phosphate solution was added to smoked sausage, as a new ingredient. Subsequently, the color, texture, and flavor of the samples were analyzed. The results showed that, compared with nitrite (0.075 g/kg nitrite added to sausage), the addition of 30~90% nitrite and cold-plasma-treated phosphate solution had no significant effect on the a* value or the relative content of oxygenated myoglobin (p > 0.05). The amount of residual nitrite in the smoked sausage prepared with the addition of 30~70% nitrite and cold-plasma-treated phosphate solution was significantly lower than that of the nitrite-treated group. The addition of nitrite combined with cold-plasma-treated phosphate solution had no significant effects on the texture (hardness, springiness, cohesiveness, and resilience) or the sensory evaluation of the smoked sausage. A total of 69 volatile compounds were detected, and 20 of them had VIP (Variable Importance Plot) scores higher than one. In conclusion, cold plasma treatment represents a potential technology to partially substitute nitrite. This study provides new methods for the application of this nitrite substitute.