Colour stability and lipid oxidation of fresh beef. Development of a response surface model for predicting the effects of temperature, storage time, and modified atmosphere composition

Carnobacterium maltaromaticum as bioprotective culture against spoilage bacteria in ground meat and cooked ham

This study assessed the bioprotective effect of Carnobacterium maltaromaticum (CM) against Pseudomonas fluorescens (PF) and Brochothrix thermosphacta (BT) in ground beef and sliced cooked ham stored in high- and low-oxygen-modified atmospheres (66/4/30% O2/N2/CO2 and 70/30% N2/CO2, respectively). Both meat products were inoculated with CM, PF, and BT individually or in combination and stored for 7 days (3 days at 4 °C + 4 days at 8 °C) for ground beef and 28 days (10 days at 4 °C + 18 days at 8 °C) for sliced cooked ham. Each food matrix was assigned to 6 treatments: NC (no bacterial inoculation, representing the indigenous bacteria of meat), CM, BT, PF, CM + BT, and CM + PF. Bacterial growth, pH, instrumental color, and headspace gas composition were assessed during storage. CM counts remained stable from inoculation and throughout the shelf-life. CM reduced the population of inoculated and indigenous spoilage bacteria, including BT, PF, and enterobacteria, and showed a negligible impact on the physicochemical quality parameters of the products. Furthermore, upon simulating the shelf-life of ground beef and cooked ham, a remarkable extension could be observed with CM. Therefore, CM could be exploited as a biopreservative in meat products to enhance quality and shelf-life.

Inhibitory effects of citral on the production of virulence factors in Staphylococcus aureus and its potential application in meat preservation

Foodborne diseases caused by Staphylococcus aureus contamination on meat and meat products has gained increasing attention in recent years, while the pathogenicity of S. aureus is mainly attributed to its virulence factors production, which is primarily regulated by quorum sensing (QS) system. Herein, we aimed to uncover the inhibitory effects and mechanisms of citral (CIT) on virulence factors production by S. aureus, and further explore its potential application in pork preservation. Susceptibility test confirmed the antibacterial properties of CIT against S. aureus, the minimal inhibitory concentration (MIC) was 0.25 mg/mL. Treatment with sub-MICs of CIT reduced the hemolytic activity by inhibiting the production of α-hemolysin, and staphylococcal enterotoxins (SEs) production was significantly inhibited by CIT in both culture medium and pork without affecting bacterial growth. Transcriptomic analysis indicated that the differentially expression genes encoding α-hemolysin, SEs, and other virulence factors were down-regulated after treatment with 1/2MIC CIT. Moreover, the genes related to QS including agrA and agrC were also down-regulated, while the global transcriptional regulator sarA was up-regulated. Data here demonstrated that CIT could inhibited S. aureus virulence factors production through disturbing QS systems. In a challenge test, the addition of CIT caused a remarkable inhibition of S. aureus population and delay in lipid oxidation and color change on pork after 15 days incubation at 4 °C. These findings demonstrated that CIT could not only efficiently restrain the production of S. aureus virulence factors by disturbing QS, but also exhibit the potential application on the preservation of meat products.

Oxidative Modification, Structural Conformation, and Gel Properties of Pork Paste Protein Mediated by Oxygen Concentration in Modified Atmosphere Packaging

The objective of this study was to investigate the effect of pork oxidation through modified atmosphere packaging (MAP) on gel characteristics of myofibrillar proteins (MP) during the heat-induced gelation process. The pork longissimus thoracis (LT) was treated by MAP at varying oxygen concentrations (0, 20, 40, 60, and 80% O2) with a 5-day storage at 4 °C for the detection of MP oxidation and gel properties. The findings showed the rise of O2 concentration resulted in a significant increase of carbonyl content, disulfide bond, and particle size, and a decrease of sulfhydryl content and MP solubility (p < 0.05). The gel textural properties and water retention ability were significantly improved in MAP treatments of 0-60% O2 (p < 0.05), but deteriorated at 80% O2 level. As the concentration of O2 increased, there was a marked decrease in the α-helix content within the gel, accompanied by a simultaneous increase in β-sheet content (p < 0.05). Additionally, a judicious oxidation treatment (60% O2 in MAP) proved beneficial for crafting dense and uniform gel networks. Our data suggest that the oxidation treatment of pork mediated by O2 concentration in MAP is capable of reinforcing protein hydrophobic interaction and disulfide bond formation, thus contributing to the construction of superior gel structures and properties.

Combined Effect of Cinnamon Bark Oil and Packaging Methods on Quality of Fresh Lamb Meat Patties during Storage at 4 °C

The present study aimed to investigate the effects of adding cinnamon bark oil (CBO) on the quality of ground lamb meat, considering different packaging conditions, including modified atmospheric packaging (MAP) using Hengxian HX-300H and overwrapped packaging. The CBO was incorporated into lamb meat samples at three different levels: 0% (control), 0.025% and 0.05% (v/w). The samples were then subjected to three packaging methods: MAP1 (80% O2 + 20% CO2), MAP2 (40% O2 + 30% CO2 + 30% N2) and overwrapped packaging and stored at 4 °C for 0, 4, 8, 12 and 16 days. The findings of the present study revealed that the addition of 0.025% and 0.05% CBO under MAP1 condition significantly improved the color of the meat samples after 12 days of storage at 4 °C (p < 0.05). The overwrapped samples exhibited higher levels of thiobarbituric acid reactive substances (TBARS) compared to all other treatments, starting from day 4 of storage (p < 0.05). Furthermore, microbial counts were notably higher in the overwrapped samples than in all other samples after day 8 of storage (p < 0.05). In conclusion, the combination of 0.05% CBO with MAP proved to be an effective strategy for enhancing the color stability and oxidative stability of ground lamb meat. These results suggest that CBO can be utilized as a beneficial protective agent in meat packaging processes.

Microbiological and Sensorial Quality of Beef Meat (Longissimus dorsi) Marinated with Cinnamon Extract and Stored at Various Temperatures

Meat spoilage caused by temperature abuse is a major problem for producers, retailers, and consumers that can generate large economic losses to industries. Microbial growth of Pseudomonas spp. is the main source of spoilage during storage. Cinnamon has antimicrobial properties that may potentially be used to reduce the spoilage caused by Pseudomonas. The objectives of this study were to determine the inhibitory effect of cinnamon extract (CE) against Pseudomonas aeruginosa (ATCC 27853) and evaluate the treatment of CE on meat quality during different storage temperatures (5 °C, 10 °C, 15 °C, and 25 °C). The anti-Pseudomonas result showed that 100% (w/v) CE concentration produced a 13.50 mm zone of inhibition in a disc diffusion assay. The minimum inhibitor concentration (MIC) of CE was noted at 25% (v/v), whereas the minimum bactericidal concentration (MBC) value was observed at 50% (v/v) concentration of CE. The time-kill showed the growth of P. aeruginosa decreased from 7.64 to 5.39 log CFU/mL at MIC concentration. Total phenolic content and IC₅₀ value of the cinnamon extract was expressed as 6.72 ± 0.87 mg GAE/g extract and 0.15 mg/mL, respectively. When the meat was marinated with 50% (v/v) CE and stored at various temperatures, the total viable count (TVC) and growth of Pseudomonas spp. were lowered as compared to the control sample. However, the reduction in microbial count in all samples was influenced by the storage temperature, where the lowered microbial count was noted in the sample treated with CE and stored at 5 and 10 °C for 48 h. The pH of meat treated with or without CE ranged from pH 5.74 to 6.48. The sensory attributes of colour, texture, and overall acceptability have a significant difference, except for odour, between marinated meat and control. The results indicate that the use of cinnamon extract as the marination agent for meat could reduce the growth of Pseudomonas spp. and therefore assist in extending the shelf life of meat at 5 and 10 °C storage temperatures.

Impact of Modified Atmospheres on Growth and Metabolism of Meat-Spoilage Relevant Photobacterium spp. as Predicted by Comparative Proteomics

Modified atmosphere packaging (MAP) is a common strategy to selectively prevent the growth of certain species of meat spoiling bacteria. This study aimed to determine the impact of high oxygen MAP (70% O₂, 30% CO₂, red and white meats) and oxygen-free MAP (70% N₂, 30% CO₂, also white meat and seafood) on preventing the growth of spoiling photobacteria on meat. Growth of Photobacterium carnosum and P. phosphoreum was monitored in a meat simulation media under different gas mixtures of nitrogen, oxygen, and carbon dioxide, and samples were taken during exponential growth for a comparative proteomic analysis. Growth under air atmosphere appears optimal, particularly for P. carnosum. Enhanced protein accumulation affected energy metabolism, respiration, oxygen consuming reactions, and lipid usage. However, all the other atmospheres show some degree of growth reduction. An increase in oxygen concentration leads to an increase in enzymes counteracting oxidative stress for both species and enhancement of heme utilization and iron-sulfur cluster assembly proteins for P. phosphoreum. Absence of oxygen appears to switch the metabolism toward fermentative pathways where either ribose (P. phosphoreum) or glycogen (P. carnosum) appear to be the preferred substrates. Additionally, it promotes the use of alternative electron donors/acceptors, mainly formate and nitrate/nitrite. Stress response is manifested as an enhanced accumulation of enzymes that is able to produce ammonia (e.g., carbonic anhydrase, hydroxylamine reductase) and regulate osmotic stress. Our results suggest that photobacteria do not sense the environmental levels of carbon dioxide, but rather adapt to their own anaerobic metabolism. The regulation in presence of carbon dioxide is limited and strain-specific under anaerobic conditions. However, when oxygen at air-like concentration (21%) is present together with carbon dioxide (30%), the oxidative stress appears enhanced compared to air conditions (very low carbon dioxide), as explained if both gases have a synergistic effect. This is further supported by the increase in oxygen concentration in the presence of carbon dioxide. The atmosphere is able to fully inhibit P. carnosum, heavily reduce P. phosphoreum growth in vitro, and trigger diversification of energy production with higher energetic cost, highlighting the importance of concomitant bacteria for their growth on raw meat under said atmosphere.

Modified Atmosphere Packaging of Chicken Thigh Meat: Physicochemical and Sensory Characteristics during the Frozen Storage Period

This study aimed to explore the utilization of modified atmosphere packaging (MAP) for chicken thigh meat pieces (CTMP) during frozen storage periods (FSP) of 1, 30, 60, and 90 days at −18°C. The treatments were divided into seven groups which are control, vacuum, 15% O2/15% N2/70% CO2, 30% N2/70% CO2, 50% O2/50% N2, 30% O2/70% CO2, and 1.5 ml clove essential oil. The results showed that treatment of 30% N2/70% CO2 was associated with a lower pH value than control. The pH, drip loss, TBA, peroxide number, and fatty acid percentage values were significantly ( $p<0.05$ ) increased as FSP rises. The effect of the MAP and muscle fiber index (MFI) was significantly different ( $p<0.05$ ) by the FSP. A decrease in the drip loss during storage and cooking when samples were treated with a MAP of 15% O2/15% N2/70% CO2, 30% N2/70% CO2, and clove oil groups were noted. The lowest values of TBA, peroxide number, and fatty acid percentage were recorded using 15% O2/15% N2/70% CO2, 30% N2/70% CO2, and clove oil groups, respectively. There was an improvement in all sensory characteristics of all MAP and clove oil treatments.

The pathogenic and spoilage bacteria associated with red meat and application of different approaches of high CO2 packaging to extend product shelf-life

With the fast-global development of packaging techniques, the potential antimicrobial effect of CO₂, as a safe, cheap and readily available gas, makes it the integral component for packaging of meat products. The associated spoilage and/or pathogenic bacteria on raw meat may respond in different ways to elevated CO₂ concentrations. The growth of some aerobic Gram-negative bacteria such as Pseudomonas spp. is significantly inhibited but some LAB bacteria may be allowed to grow faster and dominate the product. The antimicrobial efficacy of enriched CO₂ packaging is attributed to the rate of CO₂ solubility in the product which is itself affected by the level of headspace CO₂, product pH, temperature and the ratio of headspace gas to product (G:P). This review, first, explores the varied range of beef and sheep meat spoilage and pathogenic bacteria and the intrinsic and extrinsic parameters that may influence the pattern of microbial growth and meat spoilage rate during storage. Then, the antimicrobial mechanism of elevated CO₂ packaging will be discussed and the different approaches of achieving enriched CO₂ packaging i.e. the traditional technique of flushing a desired gas mixture and/or using the new commercially developed CO₂ emitters will then be compared in terms of their strengths, limitations and technical mode of action.

The Relationship between Lipid Content in Ground Beef Patties with Rate of Discoloration and Lipid Oxidation during Simulated Retail Display

The relationships between the lipid content, lipid oxidation, and discoloration rate of ground beef during a simulated retail display were characterized in this study. A total of 276 batches of ground beef were manufactured with inside rounds and subcutaneous fat from 138 beef carcasses at different targeted levels of lean:fat. There was a total of four different targeted grind levels during the manufacture of the ground beef, and the lipid content for the samples used in this study ranged from 2% to 32% total lipid. Fatty acid composition was determined based on subcutaneous fat, whereas the proximate composition of moisture and total lipids, instrumental color, visual discoloration, and lipid oxidation measured as thiobarbituric acid reactive substances were evaluated on ground beef patties during 7 days of simulated retail at 4 °C display under LED lights. Analysis for the correlation and the creation of linear regression models indicated that lipid content played a more critical role in the discoloration rate compared to lipid oxidation and fatty acid composition. Lipid oxidation could be more reliably predicted by lipid content and instrumental color compared to visual discoloration. Overall, ground beef formulated with greater lipid content is expected to experience greater rates of lipid oxidation and discoloration during retail display.

Impact of Packaging Film and Beef Trimmings on Ground Beef Shelf Life

Fresh beef storage in the retail setting can be presented in a variety of packaging methods, and identifying an alternative such as vacuum packaging to current traditional methods could potentially increase shelf life and reduce meat waste. The objective of this study was to identify the influence of packaging film and lean trimming sources on fresh ground beef surface color during a simulated retail display period. There were no differences (p > 0.05) in surface color redness (a*), yellowness (b*), chroma, or hue angle regardless of packaging film or lean trimmings. However, thiobarbituric acid reactive substances (TBARS) were greater (p < 0.05) for packages containing a greater percentage of CULL beef trimmings regardless of packaging film. In addition, pH values of ground beef packages did not differ (p > 0.05) among packaging film or lean trimming blends. Visual color did not differ (p > 0.05) throughout the simulated retail display period regardless of beef trimmings or packaging film. Microbial spoilage organisms were greater (p < 0.05) after the simulated display period. These results suggest that ground beef presented in a simulated retail setting using an alternative packaging platform, such as vacuum packaging, is plausible.

Influence of frying parameters and optimization of deep fat frying conditions on the physicochemical and textural properties of chicken nuggets from FUNAAB-Alpha broilers

Abstract

Influence of deep fat frying parameters on quality attributes of chicken nuggets from FUNAAB-Alpha broilers and optimization of the process using Box-Behnken experimental design of response surface methodology was investigated. Fried chicken nuggets were obtained using frying temperature (155–175 °C), frying time (3–7 min) and sample thickness (0.5–2.5 cm) as independent variables. Oil and moisture contents, texture (hardness, chewiness, adhesiveness, cohesiveness and springiness) and colour (L*, a* and b*) of samples were analyzed using standard procedures. Significance of each term in polynomial regression equations was evaluated on quality attributes. The accuracy of the regression models varied between 0.727 and 0.939. The effect of frying temperature on quality attributes of fried chicken nuggets was more significant (p > 0.05). The optimum frying temperature, frying time and sample thickness are determined as 175 °C, 3 min, 2.32 cm, respectively. Absolute percent error between optimized and experimental data were within the acceptable limit.

Graphic abstract

Action mode of cranberry anthocyanin on physiological and morphological properties of Staphylococcus aureus and its application in cooked meat

This study researched the action mode of cranberry anthocyanin (CA) against Staphylococcus aureus and the effect of CA on the counts of S. aureus and the quantity of cooked meat during storage. The antibacterial effect was assessed by minimum inhibitory concentration (MIC) and survival populations of S. aureus strains after CA treatments. The changes in intracellular adenosine 5'-triphosphate (ATP) concentration, cell membrane potential, content of bacterial protein and cell morphology were analyzed to reveal possible action mode. Application potentials of CA as antimicrobial agent were assessed during storage of cooked pork and beef. The result showed that the MIC of CA against S. aureus strains was 5 mg/mL. Approximately 8 log CFU/mL of S. aureus strains can be completely inhibited after treatment with 2.0 MIC of CA for 0.5 h. Treatments of CA resulted in lower intracellular ATP and soluble protein levels, damaged membrane structure and leakage of cytoplasmic. Application of CA on cooked pork and beef caused a significant decrease in S. aureus counts and pH values, and color-darkening compared with control samples. These findings demonstrated that CA played an effective antimicrobial against S. aureus and had a potential as natural preservative to inhibit the growth of food pathogens.

Impact of myoglobin oxygenation level on color stability of frozen beef steaks

The emerging market of frozen meat emphasizes the need to better understand beef surface discoloration and the ideal parameters of freezing beef to retain an acceptable color. The objectives of this study were to determine the impacts of myoglobin oxygenation level prior to freezing and frozen storage duration on frozen beef color. USDA Choice strip loins (n = 36) were aged for 4 d or 20 d. Steaks were randomly assigned to a myoglobin oxygenation level [deoxygenated (DeOxy; immediately packaged after cutting), oxygenated (Oxy; oxygenated in air for 30 min), or highly oxygenated (HiOxy; packaged for 24 h in 80% O2)]. Steaks were then vacuum packaged in oxygen permeable or impermeable film and immediately frozen (-5 °C). Following either 0, 2, 4, or 6 mo of frozen storage, steaks were removed from the packaging and immediately analyzed for instrumental color (L*, a*, and b*), percent oxymyoglobin, metmyoglobin, and deoxymyoglobin, delta E, redness ratio, a*:b* ratio, hue angle, subjective discoloration, and lipid oxidation. The HiOxy steaks had greater oxygen penetration and the greatest a* values compared with DeOxy and Oxy steaks, regardless of packaging (P < 0.0005). With 4 d of aging, HiOxy steaks had greater a* values than DeOxy and Oxy at all storage times (P = 0.0118). The HiOxy steaks aged for 20 d and frozen for 6 mo had significantly higher delta E values than all other myoglobin oxygenation levels and postmortem aging periods (P < 0.0001). Redness and percent oxymyoglobin were highest for HiOxy steaks within each storage period (P < 0.0002). The HiOxy steaks had the highest percent oxymyoglobin and DeOxy had the lowest percent oxymyoglobin within each aging and storage period (P < 0.01). Conversely, DeOxy steaks had the highest percent metmyoglobin and HiOxy had the lowest percent metmyoglobin when packaged in impermeable film (P < 0.0001). The HiOxy steaks from 20 d of aging had the highest discoloration compared with 4 d aging and more discoloration than all other myoglobin treatments at 6 mo of storage (P < 0.0001). The HiOxy 20 d aged steaks exhibited the highest lipid oxidation values at 2, 4, and 6 mo (P = 0.0224) and HiOxy steaks exhibited a brighter and deeper cherry red color compared with the DeOxy steaks. The HiOxy steaks were greater in redness or similar when compared with Oxy steaks, but experienced more detrimental effects when frozen storage was extended.

Effects of probiotic supplementation and postmortem storage condition on the oxidative stability of M. Pectoralis major of laying hens

Dietary probiotic supplementation is a promising alternative to antibiotics in the poultry industry, and some studies have found its positive impacts on meat quality attributes. The objective of this study was to evaluate the effects of dietary treatments on oxidative stability of postmortem chicken fillet (M. Pectoralis major) muscles during 7 d of storage under either high oxygen (HIOX) or vacuum (VAC) conditions. A total of 264 Hy-Line Brown laying hens (11 birds per cage) were assigned to 2 different dietary treatments (regular diet or 300 ppm probiotic, Sporulin enhanced diet) before being sacrificed. At 17 wk, one bird per cage from 6 cages per treatment was randomly selected and slaughtered (n = 12). Chicken fillets from both sides were collected and randomly assigned to HIOX or VAC conditions. Within each fillet side, the muscle was divided into 3 portions, assigned to 1 or 7 d storage period, while the caudal portion was allocated as the 0 d samples for proximate composition and fatty acid profiling. Results revealed that the muscle crude compositions were not altered in laying hens that were fed probiotic supplementary diet compared to controls (P > 0.05). However, the muscle samples from probiotic fed laying hens had higher proportions of unsaturated fatty acid (74.76 vs. 71.65%, P < 0.05) and 2-thiobarbituric acid reactive substances (0.79 vs. 0.67 mg malondialdehyde/kg meat, P < 0.05) than the samples from the control. In addition, the probiotic fed laying hens, but not controls, had higher levels of conjugated dienes (3.32 vs. 2.63 μg/g meat) and peroxides (0.40 vs. 0.30 milliequivalent O₂/kg fat) in the muscle samples after 7 d of storage (P < 0.05). The results from the present study indicated that postmortem fillet muscles obtained from the laying hens fed with probiotic supplementation would be more prone to be oxidized, especially under more oxidizing conditions (HIOX and extended storage time).

Electric Field Induced Super-cooling System for Long Term Dry-aged Beef Loin

This study investigates the utilization of an electric-field-induced super cooling system in long-term dry aging of beef loin. Analyzed quality properties of dry-aged beef loin applied with electric field refrigeration (EFR) versus commercial refrigeration (CR). Quality properties was including aging loss, pH, water holding capacity (WHC), cooking loss, color, warner-bractzler shear force (WBSF), total plate count (TPC), and thiobarbituric acid reactive substances (TBARS). Aging loss of wk 1 EFR was significantly lower than CR (p<0.05). pH of EFR was slow change tendency compared CR. WHC of both aging methods were higher with increase in aging duration. Cooking loss of wk 1, 2, 4, and 10 EFR were significantly lower than CR (p<0.05). Lightness and redness of EFR was slow change tendency compared CR. However, yellowness of EFR was increased until wk 2, 3, and significantly decreased at wk 10 (p<0.05), but yellowness of CR was decreased until wk 3 and significantly increased with an increasing aging weeks (p<0.05). Both aging methods of WBSF was decreased with increase in aging weeks; however, wk 10 of CR was significantly lower than EFR (p<0.05). TPC after wk 3 EFR groups were significantly lower than CR groups (p<0.05), and TBARS of EFR groups were significantly lower than CR (p<0.05). The present results show that application of the EFR system for dry aging beef loin can extends its shelf life and induce changes of several aging properties in similar to commercial aging.

Supercooling preservation technology in food and biological samples: a review focused on electric and magnetic field applications

Freezing has been widely recognized as the most common process for long-term preservation of perishable foods; however, unavoidable damages associated with ice crystal formation lead to unacceptable quality losses during storage. As an alternative, supercooling preservation has a great potential to extend the shelf-life and maintain quality attributes of fresh foods without freezing damage. Investigations for the application of external electric field (EF) and magnetic field (MF) have theorized that EF and MF appear to be able to control ice nucleation by interacting with water molecules in foods and biomaterials; however, many questions remain open in terms of their roles and influences on ice nucleation with little consensus in the literature and a lack of clear understanding of the underlying mechanisms. This review is focused on understanding of ice nucleation processes and introducing the applications of EF and MF for preservation of food and biological materials.

High Oxygen Modified Atmosphere Packaging Negatively Influences Consumer Acceptability Traits of Pork

Current trends in meat packaging have seen a shift from conventional overwrap to vacuum packing (VAC) and modified atmosphere packaging (MAP). The aim of this experiment was to investigate the effects of high oxygen MAP (HiOxMAP) of pork loins compared with vacuum packed (VAC) on eating quality and colour, after storage in simulated illuminated retail display conditions. Pork loins (n = 40) were cut and stored under two packaging methods (HiOxMAP, 80% O₂, 20% CO₂; VAC) for up to 14 days, with samples taken at various times for measurements. After 7 days of storage, HiOxMAP samples exhibited inferior consumer acceptability for tenderness, flavor, overall liking, quality and re-purchase intention as well as higher shear force and hardness, relative to VAC samples (p < 0.05 for all). Loins stored in HiOxMAP had higher lightness (L*), redness (a*) and yellowness (b*) values at 3 and 7 days, but lower ratio of oxymoglobin to metmyoglobin (oxy/met) values in the meat surface at 14 days of display, relative to VAC samples (p < 0.05 for all). The oxy/met ratio declined from 2.3 to 1.7 between days 3 and 14 of display in HiOxMAP samples (p < 0.05), whereas the ratio was similar and stayed relatively high for VAC samples. VAC samples produced consistently higher colour values (a*, b*, oxy/met) when left to bloom 30 min after removal from packaging (p < 0.05). Lipid oxidation values, measured using thiobarbituric acid reactive substances, in HiOxMAP pork loins, were higher at all time points compared to VAC during the 14 day storage period (p < 0.05). The use of vacuum packing for retail shelves, should be considered as the preferred option, over HiOxMAP.

Effects of naturally-produced lovastatin on carcass characteristics, muscle physico-chemical properties and lipid oxidation and cholesterol content in goats

This study investigated the carcass characteristics, physico-chemical properties, storage stability and cholesterol content of meat from goats fed with different levels of naturally-produced lovastatin used to mitigate enteric methane production. Twenty intact Saanen male goats of 5-6 months old with initial live weight of 25.8 ± 4.0 kg were randomly allotted into four dietary treatments containing 0 (Control), 2 (Low), 4 (Medium) and 6 mg (High) per kg live weight (LW) of naturally-produced lovastatin for 12 consecutive weeks. No differences were found in all the parameters measured except for full LW, hot and cold carcass weight, shear force, color and cholesterol content among the treatment groups. Aging had significant effects on all the parameters measured in this study except a* (redness) of meat. Meat samples in the Medium and High treatments were of higher lightness and yellowness, more tender and lower cholesterol levels. We conclude that, in addition to mitigate enteric methane emissions, dietary supplementation of naturally-produced lovastatin at 4 mg/kg LW could be a feasible feeding strategy to produce tender meat containing lower cholesterol.

Modified atmosphere packaging for lamb meat: evaluation of gas composition in the extension of shelf life and consumer acceptance

Convenience foods like chilled meat usually have a short shelf life. Modified atmosphere packaging (MAP) can be used together with refrigeration to retard meat degradation. This work evaluated the effect of MAP on the preservation and consumers acceptance of lamb meat. Lamb loins Longissimus lumborum were packed in five conditions: 15% O₂ + 85% CO₂ (O15), 30% O₂ + 70% CO₂ (O30), 45% O₂ + 55% CO₂ (O45), 60% O₂ + 40% CO₂ (O60), and Vacuum (control). Physicochemical, sensory, and microbiological analyses were carried out along 21 days of refrigerated (1 ± 1 °C) storage. Treatments O30, O45 and vacuum presented the lowest oxidation values: 0.60, 0.61 and 0.30 Malonaldehyde Kg^-1 respectively. Treatment O45 showed the highest a* until the seventh day of storage (16.64). In the sensory preference ranking test, O30 and O45 received best scores in the first and second weeks of storage, respectively. Treatments O30 and O45 delivered products with lower microbial counts than the other ones. Considering a balance between consumer preference and microbiological results, we propose the use of 45% O₂ + 55% CO₂ gas composition to extend the shelf life of lamb loin.

Dietary vitamin E dosage and source affects meat quality parameters in light weight lambs

BACKGROUND

Supra-nutritional vitamin E supplementation is a commonly used approach to delay lipid oxidation and colour deterioration in lamb and beef meat marketed under modified atmosphere packaging. However, these applications lack a precise calibration of dose for the desired effect and, in addition, limited information is available regarding the use of natural vitamin E for this purpose.

RESULTS

Three hundred and sixty Rasa Aragonesa lambs were fed diets supplemented with all-rac-α-tocopheryl acetate (250, 500, 1000 and 2000 mg kg^-1 compound feed), RRR-α-tocopheryl acetate (125, 250, 500 and 1000 mg kg^-1 compound feed) and a basal diet without vitamin E supplementation for 14 days before slaughter at 25.8 ± 1.67 kg body weight. Vitamin E supplementation had no effect (P > 0.05) on average daily weight gain, feed intake and feed efficiency. Display time had larger effects on lipid oxidation, colour stability, myoglobin forms and meat discolouration parameters compared to vitamin E supplementation. However, vitamin E source and dosage significantly extended meat shelf-life as indicated by lipid oxidation, redness, hue angle, metmyoglobin formation, deoxymyoglobin formation, A_580-630 and I_SO2 .

CONCLUSION

The quantification of these effects demonstrated that the biological activity value of 1.36 used to distinguish both vitamin E sources is not appropriate for meat quality enhancing properties. © 2017 Society of Chemical Industry.

Carbon Monoxide in Meat and Fish Packaging: Advantages and Limits

Due to increased demands for greater expectation in relation to quality, convenience, safety and extended shelf-life, combined with growing demand from retailers for cost-effective extensions of fresh muscle foods’ shelf-life, the food packaging industry quickly developed to meet these expectations. During the last few decades, modified atmosphere packaging (MAP) of foods has been a promising area of research, but much remains to be known regarding the use of unconventional gases such carbon monoxide (CO). The use of CO for meat and seafood packaging is not allowed in most countries due to the potential toxic effect, and its use is controversial in some countries. The commercial application of CO in food packaging was not then considered feasible because of possible environmental hazards for workers. CO has previously been reported to mask muscle foods’ spoilage, and this was the primary concern raised for the prohibition, as this may mislead consumers. This review was undertaken to present the most comprehensive and current overview of the widely-available, scattered information about the use of CO in the preservation of muscle foods. The advantages of CO and its industrial limits are presented and discussed. The most recent literature on the consumer safety issues related to the use of CO and consumer acceptance of CO especially in meat packaging systems were also discussed. Recommendations and future prospects were addressed for food industries, consumers and regulators on what would be a “best practice” in the use of CO in food packaging. All this promotes high ethical standards in commercial communications by means of effective regulation, for the benefit of consumers and businesses in the world, and this implies that industrialized countries and members of their regulatory agencies must develop a coherent and robust systems of regulation and control that can respond effectively to new challenges.

Influence of Skin Packaging on Raw Beef Quality: A Review

A detailed revision of several aspects related to the application of skin packaging to raw beef was considered. Skin packaging, a relatively new technique derived from vacuum packaging, was developed with the aim of retailing small portions of fresh meat, minced meat, or meat preparations. Above all, the influence of this typology of packaging on the microbial population of raw meat was studied, with particular attention to total viable count, aerobic spoilage bacteria, anaerobic bacteria,Enterobacteriaceae, Brochothrix thermosphacta,and lactic acid bacteria. Moreover, the effect on acidification by LAB was also deepened. As colour is the main characteristic influencing purchase decisions at the point of sale, the effect of skin packaging on this parameter was evaluated for raw meat but also for cooked meat. Tenderness, juiciness, and the ability to hold liquid of raw meat when packed in skin conditions were also considered. Furthermore, odour and flavour were considered as sensorial parameters possibly affected by skin packaging. Finally, acceptability by consumer was also investigated. In the studies considered, results showed that skin packaging is advantageous in terms of maintenance of meat quality and for prolonging shelf-life, improving the stability of the products.

Exogenous and Endogenous Factors Influencing Color of Fresh Meat from Ungulates

Biochemistry of post-mortem muscle tissue is complex, and several factors affect the fresh meat color and color stability, both of which influence consumer acceptance. Therefore, improving meat color and meat color stability is of significant value to the meat industry and consumers. While extensive literature is available on the color and color stability of domestic ungulates, literature on wild ungulates is notably lacking. With an increasing global demand for meats from wild ungulates, it is critical to identify the knowledge gaps regarding their color and color stability. The objective of this paper is to overview the exogenous and endogenous factors influencing the color and color stability of fresh meats from domestic and wild ungulates. The literature highlighted that the pre- and post-harvest factors influencing meat color and meat color stability are interrelated and not mutually exclusive. Current research indicates that the effects of several of these factors are specific to species, breed, and muscle source. Novel ways to manipulate these factors using a biosystems approach should be explored to improve color attributes of fresh ungulate meats.

Effects of self-carbon dioxide-generation material for active packaging on pH, water-holding capacity, meat color, lipid oxidation and microbial growth in beef during cold storage

BACKGROUND

Active packaging refers to the mixing of additive agents into packaging materials with the purpose of maintaining or extending food product quality and shelf life. The aim of this study was to develop an easy and cheap active packaging for beef. Beef loin samples were divided into three packaging groups (C, ziplock bag packaging; T1, vacuum packaging; T2, active packaging) and stored at 4 °C for 21 days.

RESULTS

The water-holding capacity was significantly (P < 0.05) higher in C and T2 than in T1 for up to 7 days of storage. The TBARS value was significantly (P < 0.05) lower in T1 and T2 after 7 days of storage. The counts of some microorganism were significantly (P < 0.05) lower in T1 and T2 after 7 days of storage; the total bacterial count and Escherichia coli count were lowest in T2 at the end of storage.

CONCLUSION

These results indicate that active packaging using self-CO₂ -generation materials can extend the shelf life similarly to that observed with vacuum packaging, and that the active packaging method can improve the quality characteristics of beef during cold storage. © 2017 Society of Chemical Industry.

The effect of the packaging system and storage time on myofibrillar protein degradation and oxidation process in relation to beef tenderness

This study investigated the impact of packaging systems on the degradation and oxidation of beef proteins regarding beef tenderness of longissimus lumborum (LL) and biceps femoris (BF) muscles stored in vacuum skin packaging (VSP), a modified atmosphere with high oxygen concentration (MAP), and combined of these two methods (VSP+MAP). A significant decrease in the Warner-Bratzler shear force (WBSF) in VSP at D14 and D28 for LL was observed compared to BF. A significant effect of packaging system on troponin-T (Tn-T) and desmin degradation was shown (p≤0.001). A high concentration of oxygen in MAP and VSP+MAP affected protein oxidation, which was reflected in myosin oxidative cross-linking. An increase of WBSF values detected in steaks packed in VSP and VSP+MAP systems could be caused by the intensification of protein oxidation. Furthermore, BF was more susceptible to oxidation compared to LL. The VSP+MAP packaging system has resulted in the maintenance of a bright, red color, however has not improved the beef tenderness.

Effect of including whole linseed and vitamin E in the diet of young bulls slaughtered at two fat covers on the sensory quality of beef packaged in two different packaging systems

BACKGROUND

Forty-six Pirenaica young bulls, slaughtered at two levels of fatness (3 and 4 mm), were used to evaluate the effect of the inclusion of 50 g kg^-1 linseed alone or with 200 IU vitamin E kg^-1 in the concentrate and of the meat packaging system (vacuum or modified atmosphere packaging (MAP)) on the beef sensory quality.

RESULTS

The inclusion of linseed or supplementation with vitamin E in the concentrate induced no significant differences in the main meat sensory scores and overall appraisal except under MAP, where small differences due to concentrate ingredients were found in juiciness and metallic flavor intensity. Extending the display time up to 4 or 8 days in high-oxygen MAP had detrimental effects on sensory attributes. Meat from animals with 4 mm fat cover depth were rated more tender and juicy, less fibrous and with a higher intensity of beef flavor and rancid odor than meat from 3 mm fat cover bulls when both samples were vacuum packaged.

CONCLUSION

The inclusion of 50 g kg^-1 linseed in the concentrate fed to bulls had no detrimental effect on the beef sensory quality. The vacuum-packaged meat of bulls slaughtered at 4 mm fat cover was rated higher on sensory analysis than that at 3 mm fat cover. © 2016 Society of Chemical Industry.

The effect of different gas permeability of packaging on physicochemical and microbiological parameters of pork loin storage under high O2 modified atmosphere packaging conditions

The aim of this study was to determine the influence of different packaging materials on meat quality during cold storage. Therefore pork loins (m. longissimus thoracis et lumborum) obtained from crossbred pigs (Polish Landrance x Duroc, n = 6) were stored at 2 ℃ in modified atmosphere packs (80% O₂, 20% CO₂) in four types of trays, which differ in gas permeability. Physicochemical (headspace gas composition, pH, colour, drip loss, cooking loss, shear force, the basic composition and fatty acid profile) and microbiological ( Salmonella spp., Escherichia coli, Enterobacteriaceae, total aerobic plates count, total psychrotrophic bacteria count, the number of lactic acid bacteria, Pseudomonas spp., the general amount of yeast and mold) parameters were monitored for up to 12 days. At the end of the storage period no differences in most physicochemical properties of pork loin due to type of packaging were found, however trays with high gas permeability had the greatest impact on total aerobic plates count and Pseudomonas spp. growth.

Rapid Discoloration of Aged Beef Muscles after Short-Term/Extreme Temperature Abuse during Retail Display

The objective of this study was to evaluate the effects of a short-term/extreme temperature abuse (STA) on color characteristics and oxidative stability of aged beef muscles during simulated retail display. Two beef muscles (longissimus lumborum, LL and semitendinosus, ST) were aged for 7 (A7), 14 (A14), 21 (A21), and 28 d (A28), and further displayed at 2℃ for 7 d. The STA was induced by placing steak samples at 20℃ for 1 h on the 4th d of display. Instrumental and visual color evaluations, ferric ion reducing capacity (FRC) and 2-thiobarbituric acid reactive substances (TBARS) assay were performed. Initially, redness, yellowness and hue angle of all beef muscles were similar, regardless of aging time before display (p>0.05). An increase in postmortem aging time increased lipid oxidation and caused a rapid discoloration after STA during display (p<0.05). ST muscle was more sharply discolored and oxidized after STA, when compared to LL muscle (p<0.05). The FRC value of beef muscles was decreased after 7 d of display (p<0.05). The results from the current study indicate adverse impacts of postmortem aging on color and oxidative stabilities of beef muscles, particularly under temperature abusing conditions during retail display. Thus, developing a specific post-harvest strategy to control quality attributes in retail levels for different muscle types and aging conditions would be required.