The Effects of Natural Antioxidants on Protein Oxidation, Lipid Oxidation, Color, and Sensory Attributes of Beef Patties during Cold Storage at 4℃

Mānuka Oil vs. Rosemary Oil: Antimicrobial Efficacies in Wagyu and Commercial Beef against Selected Pathogenic Microbes

Essential oils possessing antimicrobial characteristics have acquired considerable interest as an alternative to chemical preservatives in food products. This research hypothesizes that mānuka (MO) and kānuka (KO) oils may possess antimicrobial characteristics and have the potential to be used as natural preservatives for food applications. Initial experimentation was conducted to characterize MOs (with 5, 25, and 40% triketone contents), rosemary oil (RO) along with kanuka oil (KO) for their antibacterial efficacy against selected Gram-negative (Salmonella spp. and Escherichia coli), and Gram-positive (Listeria monocytogenes and Staphylococcus aureus) bacteria through disc diffusion and broth dilution assays. All MOs showed a higher antimicrobial effect against L. monocytogenes and S. aureus with a minimum inhibitory concentration below 0.04%, compared with KO (0.63%) and RO (2.5%). In chemical composition, α-pinene in KO, 1, 8 cineole in RO, calamenene, and leptospermone in MO were the major compounds, confirmed through Gas-chromatography-mass spectrometry analysis. Further, the antimicrobial effect of MO and RO in vacuum-packed beef pastes prepared from New Zealand commercial breed (3% fat) and wagyu (12% fat) beef tenderloins during 16 days of refrigerated storage was compared with sodium nitrate (SN) and control (without added oil). In both meat types, compared with the SN-treated and control samples, lower growth of L. monocytogenes and S. aureus in MO- and RO- treated samples was observed. However, for Salmonella and E. coli, RO treatment inhibited microbial growth most effectively. The results suggest the potential use of MO as a partial replacement for synthetic preservatives like sodium nitrate in meats, especially against L. monocytogenes and S. aureus.

Effect of Bamboo Essential Oil on the Oxidative Stability, Microbial Attributes and Sensory Quality of Chicken Meatballs

This study explores the efficacy of bamboo essential oil (BEO) incorporated at 15 ppm (T1, BEO-I) and 30 ppm (T2, BEO-II) on the overall physicochemical and oxidative stability, microbial deterioration, and sensory acceptability of meatballs stored for 20 days under refrigerated conditions. Analysis of various parameters, including physicochemical quality, color (CIE L*, CIE a* and CIE b*), generation of oxidative products (TBARS), microbial growth, and sensory acceptability of meatballs were evaluated at 5-day intervals. In addition, the total phenolics and flavonoid content of BEO were estimated, and fatty acids were determined by Gas chromatography (GC.) To gain insights into the biological activities of the BEO, antioxidant assays were determined in vitro using various methods. The antibacterial activity of BEO was also evaluated against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Vibrio cholera, Salmonella Typhimurium, Shigella flexneri, Proteus vulgaris, Escherichia coli and Klebsiella pneumoniae) bacterial strains. The BEO contained a good quantity of total phenolics and flavonoids. In addition, the oil exhibited very potent antioxidant activity scavenging reactive oxygen and other such species, effectively showing IC₅₀ at a very minimal concentration. Further, the BEO exhibited a strong antibacterial effect with MICs within 2 µL and MBCs from 5 to 7 µL for Gram-positive as well as Gram-negative bacteria, respectively. At both the concentrations used, BEO did not show any negative effect on the color of cooked meatballs but rather increased the microbiological and oxidative stability during the overall storage period. Meatballs treated with BEO had considerably reduced oxidative changes in terms of TBARS levels compared to the control. The total viable microbial count was lowest in BEO-treated meatballs and the highest in control. Both control and treated meatballs had a desirable flavor and good acceptability. The sensory attributes and aroma of treated meatballs were better and acceptable during the storage study, whereas the control samples were disliked by the panelists on 15th day. From this study, it can be concluded that bamboo essential oil could be used as a benign and non-toxic preservative to improve the quality and shelf life of cooked meatballs stored under refrigerated conditions.

Safety achievement and shelf-life prolongation of poultry breast meats by polylactic acid active packaging and gamma-irradiation

Active packaging incorporated with volatile oils is a promising technology to extend the shelf-life of perishable food. Therefore, the present work aimed at producing composite pouches based on polylactic acid incorporated with a mixture of lemongrass and cumin essential oils (PLA/mix oil). The effect on the shelf-life of fresh poultry breasts was determined on samples packaged in the PLA/mix oil alone and in combination with gamma-irradiation, and stored under refrigeration through microbiological, physicochemical, and sensorial analyses. The effect of active packaging and gamma-irradiation on artificially inoculated foodborne bacteria (Escherichia coli O157:H7 ATCC 25922, Salmonella Enteritidis, Listeria monocytogenes ATCC 35152) in poultry breasts was evaluated. When compared to control, poultry breast samples packaged in the PLA/mix oil and irradiated at 4 kGy alone decreased microbial count, maintained colour and pH values, and increased TBARS index at a lower rate, thus extended the shelf-life by 21 and 14 d, respectively. However, the combination of PLA/mix oil and gamma-irradiation at 2 kGy (PLA/mix oil + 2 kGy) was more effective in decreasing all microbial counts and extending the shelf-life by more than 28 d. Initial load of S. Enteritidis, E. coli, and L. monocytogenes inoculated in poultry breasts decreased by 3.03, 2.98, and 3.19 log CFU/g, respectively, after 3 d of storage in PLA/mix oil packaging, while the combination between PLA/mix oil and gamma-irradiation at 2 kGy (PLA/mix oil + 2 kGy) caused a synergistic impact with an increase in radiosensitivity of S. Enteritidis, E. coli, and L. monocytogenes by 3.53, 4.47, and 4.23 log CFU/g, respectively, after one day of storage as compared to the control. Active packaging (PLA/mix oil) alone and in combination with gamma-irradiation can be considered an innovative technology that could have a major effect on the prolongation of shelf-life and safety of poultry breast meats. Moreover, this new technology represents a promising alternative to commercial and unsustainable plastic films.

Clove Polyphenolic Compounds Improve the Microbiological Status, Lipid Stability, and Sensory Attributes of Beef Burgers during Cold Storage

This study investigated the phenolic composition of clove powder extract (CPE), determined by high-pressure liquid chromatography, as well as the effect of the clove powder (CP) concentration (0, 2, 4, and 6%) on the quality of beef burgers during 21 days of cold storage at 4 °C. The CPE contained a high amount of total phenolic content (455.8 mg Gallic acid equivalent/g) and total flavonoid content (100.4 mg catechin equivalent/g), and it exhibited high DPPH antioxidant scavenging activity (83.9%). Gallic acid, catechol, and protocatechuic acid were the highest phenolic acids (762.6, 635.8, and 544.9 mg/100 g, respectively), and quercetin and catechin were the highest flavonoid acids (1703.1 and 1065.1 mg/100 g, respectively). Additionally, the CPE inhibited the growth of both Gram-positive and Gram-negative bacteria effectively at 100 μg/disc. The addition of the CP had no discernible influence on the pH of the meat patties. The addition of CP at 4 and 6% increased the phenolic content and antioxidant activity of the beef patties, which consequently resulted in reduced lipid oxidation and microbial spoilage throughout the storage period. Furthermore, the CP significantly (p ≤ 0.05) improved the beef burger cooking characteristics (cooking yield, fat retention, moisture retention, and shrinkage). Additionally, the sensory acceptability was higher (p ≤ 0.05) for the burgers that contained 2% and 4% CP compared with the other treatments. In conclusion, the bioactive compounds in CP can extend the shelf life and improve the safety of beef burgers.

Effect of Teucrium trifidum powder on some meat quality attributes of chevon under refrigerated storage

We investigated the effect of T. trifidum on the shelf-life and quality of chevon kept for eight days at 4 ± 1 °C in polyethylene pouches. Different powder levels of T. trifidum (0.5 %, 1.0 %, and 2.0 % w/w) and 0.02 % w/w butylated hydroxytoluene (BHT) were used to treat the chevon samples. The T. trifidum and BHT treated chevon was compared to untreated chevon (control). Colour, ferric reducing antioxidant power (FRAP), lactic acid bacteria (LAB) counts, oxidative stability, pH and total viable counts (TVC) were all measured while the samples were in storage. Treatment demonstrated a significant (P < 0.05) influence on pH with chevon preserved with T. trifidum powder (2 %), having a lower pH than the chevon preserved with BHT and the control. The colour of chevon (lightness, redness and yellowness) was shown to differ (P < 0.05) across treatments. The redness (a∗) and yellowness (b∗) reduced as the refrigeration period lengthened (P < 0.05).

In contrast, the lightness (L∗) of chevon intensified as the storage period lengthened (P < 0.05). The TBARS considerably reduced (P < 0.05) in samples subjected to T. trifidum powder and BHT, with respect to the untreated sample. There was an increase in the FRAP activity as the amount of T. trifidum powder (P < 0.05) was increased. The FRAP values were shown to be inversely related to the TBARS values, implying that the addition of T. trifidum powder could slow lipid oxidation. In comparison with the control, T. trifidum powder inhibited bacterial growth during storage as measured by a significant reduction in TVC and LAB counts (P < 0.05). It is concluded that, T. trifidum powder has potent antioxidant and antimicrobial activity in refrigerated ground chevon thus can be potentially used to preserve the quality of refrigerator stored ground chevon.

Antioxidant, Antimicrobial and Metmyoglobin Reducing Activity of Artichoke (Cynara scolymus) Powder Extract-Added Minced Meat during Frozen Storage

The present study aimed to investigate the bioactive compounds in artichoke (Cynara scolymus) powder, having antioxidant and antimicrobial activity, and to determine the effectiveness of artichoke (C. scolymus) powder extract within the minced meat. C. scolymus was extracted using two different methods. The method incorporating high phenolic and flavonoid content levels was used in other analyses and the phenolic and flavonoid contents in C. scolymus extract was determined using LC-QTOF-MS. Antioxidant, antimicrobial, and metmyoglobin (metMb) reducing activities and pH values of the extract-added minced meat samples were measured for 10 days during storage. DPPH, FRAP, and ABTS were used in the antioxidant analyses. The antimicrobial activity of C. scolymus extract was evaluated on five different food pathogens by using the disc diffusion method. The most resistant bacterium was found to be Listeria monocytogenes (18.05 mm ± 0.24). The amount of metMb was measured in the minced meat sample that was added to the extract during storage (p < 0.05). MetMb formation and pH value on the sixth day of storage were found to be at lower levels than in the control group. In conclusion, C. scolymus exhibited a good antimicrobial and antioxidant effect and can be used in storing and packaging the food products, especially the meat and meat products.

Effect of Dietary Supplementation of Bioactive Peptides on Antioxidant Potential of Broiler Breast Meat and Physicochemical Characteristics of Nuggets

Poultry meat is generally exposed to quality deterioration due to lipid oxidation during storage. Oxidative stability of meat can be increased by feed supplementation. Aim of the current study was to investigate the effect of dietary supplementation of fish waste derived bioactive peptides on antioxidant potential of broiler breast meat and physico-chemical characteristics and quality parameters of nuggets prepared from breast meat. 180 broiler birds (six groups of 30 birds) were purchased. Each group was given different concentrations of bioactive peptides i.e. 0, 50, 100, 150, 200, and 250 mg/kg feed. After completion of six weeks birds were slaughtered and breast meat was stored at -18°C for six months. Nuggets were prepared and stored at -18°C for 45 days. Meat samples were analyzed for antioxidant activity [total phenolic contents (TPC), DPPH• scavenging activity, and ferric reducing antioxidant power] and lipid oxidation assay at regular intervals of 1, 2, 3, 4, 5, and 6 months while nuggets were analyzed for quality (pH, color, texture and water holding capacity) parameters after regular interval of 15 days. A significant (p<0.05) effect of feed supplementation was observed on antioxidant status such as TPC, DPPH• scavenging activity, and FRAP of broiler breast meat. Dietary interventions of bioactive peptides significantly (p<0.05) delayed lipid oxidation of breast meat than control. All the quality parameters were also significantly affected due to dietary bioactive peptides and storage duration. Thus, dietary interventions of bioactive peptides can increase the antioxidant and shelf stability of broiler breast meat and nuggets.

Effect of heat processing on the nutrient composition, colour, and volatile odour compounds of the long-horned grasshopper Ruspolia differens serville

Heat processing is commonly used to prepare edible insects for consumption. This study aimed at determining the effect of boiling and subsequent oven roasting on Ruspolia differens' nutrient composition, colour and odor compounds. Boiling leads to: a significant increase in protein and decrease in fat content on a dry matter basis; a minimal influence on its amino and fatty acids profile; a significant reduction in its ash content due to leaching of phosphorus, potassium and sodium; a significant increase in iron, zinc, copper, manganese and calcium content; and a fivefold reduction in the amount of vitamin B12. Roasting leads to a relative increase in the amount of calcium and trace mineral elements but doesn't affect other nutrients. Roasting results into a more uniform colour intensity when green and brown polymorphs are roasted together. Lipid oxidation is responsible for the colour and aroma of heat processed R. differens.

Comparison of Butylated Hydroxytoluene, Ascorbic Acid, and Clove Extract as Antioxidants in Fresh Beef Patties at Refrigerated Storage

This study was performed to assess the comparison of the effects amongst butylated hydroxytoluene (BHT), clove extract (CE), and ascorbic acid (AA) as antioxidants on the oxidative stability and color values in fresh beef patties. The adding of BHT, AA, and CE to patties significantly restrained lipid oxidation, lowered hue angle as color value, and expanded redness and chroma values of fresh beef patties in comparison to the control (p<0.05). BHT and AA significantly led to impede the protein oxidation of patties by lowering carbonyl content (p<0.05). CE had no negative effect on protein oxidation. The antioxidant effects of BHT, AA, and CE were obviously manifested. Nonetheless, BHT, AA, and CE appeared to have insignificant difference of each other for lowering the protein oxidation at the end of storage. BHT and CE represented lowered lipid oxidation in comparison to AA. The antioxidant effects of BHT, AA, and CE on lipid oxidation were more marked than the effects on protein oxidation. Furthermore, CE as a natural antioxidant evinced the efficiency in oxidative stability and color stability in fresh beef patties. The study implied that CE could substitute the use of BHT and AA when making beef patties during storage.

Effect of Aged and Fermented Garlic Extracts as Natural Antioxidants on Lipid Oxidation in Pork Patties

The aim of this study was to investigate the natural antioxidant activity of raw garlic (RG), aged black garlic (AG), and garlic fermented with Bacillus subtilis (FG) extracts on pork patty lipid oxidation throughout refrigerated storage. The total polyphenol, total flavonoid content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity of three different types of garlic extracts were measured. The total phenolic and flavonoid content of AG was significantly higher than that of FG and RG; FG also showed a significantly higher total phenolic content than that of RG (p<0.05). The DPPH and ABTS radical scavenging activity of AG and FG was significantly higher than that of RG and that of AG was significantly higher than that of FG (p<0.05). To investigate the effect of processed garlic extracts on pork patty lipid oxidation, freeze-dried extracts of RG, FG, and AG were added to the patties at levels of 0.5% (w/w). Patties containing 0.01% (w/w) ascorbic acid (AA) and patties without treatment (CON) were compared with patties containing garlic extracts. The pH value, 2-thiobarbituric acid reactive substances value, and volatile basic nitrogen value of pork patties containing AG and FG extracts were significantly decreased compared to the other groups (CON, AA, and RG; p<0.05). Taken together, these results suggest that AG and FG extracts possess strong antioxidative activity and can serve as natural antioxidative additives to prevent pork patty lipid oxidation.