High-oxygen Packaging Research Articles

Improvement of Color and Oxidative Stabilities in Nellore Bull Dark Meat in High-Oxygen Package by Lactate and Rosemary Oil Extract

This study aimed to improve the color and oxidative stabilities of dark Nellore bull steaks with greater-than-normal ultimate pH (pHu) by the injection (8% raw wet weight basis) of a solution with L-lactate (2.5%), phosphate (0.3%) and rosemary extract (0.06%), with further packaging in high oxygen atmosphere (HiOx MAP). Longissimus lumborum muscles from pasture-fed Nellore bulls were divided into three pHu ranges: normal (<5.80), intermediate (5.81-6.19), and high (≥6.2). Muscles were then halved, with sections were randomly assigned to non-enhanced (C, n = 6/pHu range) or injected (E, n = 6/pHu range) groups, at 72 h postmortem. Each section was cut into 2 cm-slices, which were HiOx-packed and then stored for 5 days (dark) and displayed for 9 days (fluorescent lighting) at 2 °C. Higher pHu steaks exhibited greater a*, b*, h*, C* and surface oxymyoglobin and lower surface deoxymyoglobin and oxygen consumption compared to those of normal pHu between days 0 and 5 (p < 0.05). Over the time, normal-pHu muscles showed oxidative protection (lower TBARS and greater metmyoglobin reducing ability values, p < 0.05) in enhanced-steaks. Therefore, enhancement and HiOx MAP seem to produce greater-than-normal pHu Nellore bull steaks with a preferable color and quality, even after display time.

Modification of soy protein isolate using dielectric barrier discharge cold plasma assisted by modified atmosphere packaging

In this study, soy protein isolate (SPI) was treated by modified atmosphere packaging (MAP) assisted dielectric barrier discharge (DBD) cold plasma (CP) to improve its functional properties. For this reason, SPI powders were treated with DBD-CP at the oxygen ratio of 20 %, 30 %, 40 %, 50 % and 60 %, respectively. The results showed that with the increase of oxygen content, the structure of SPI was destroyed, protein macromolecule depolymerized. However, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that the primary structure of SPI was not disrupted. In addition, when the oxygen content was greater than 40 %, the solubility, water holding capacity, gelling, emulsifying and foaming properties of SPI were significantly improved (p < 0.05). The results showed that high-oxygen packaging can increase the active particles generated during processing, thereby optimizing the structural and functional properties of SPI. Therefore, MAP can serve as a more efficient method for DBD-CP to modify soybean protein.

Shelf-life extension of chilled and superchilled dark-cutting beef held under combined anoxic master packaging and high-oxygen packaging both enriched with carbon dioxide

The microbiological and quality attributes of dark-cutting (DC) beef were assessed during chilled and superchilled anoxic packaging storage (80% CO2 MP: 80% CO2/20% N2; 40% CO2 MP: 40% CO2/60% N2; VP: vacuum packaging) followed by a chilled high-oxygen packaging display period (HiOx-MAP: 60% O2/40% CO2). During storage, both MP steaks showed lower (P < 0.05) purge loss and pH than VP steaks, and superchilling significantly suppressed lipid oxidation. The following HiOx-MAP produced a bright red color in all steaks during display, and MP storage rendered displayed steaks higher (P < 0.05) redness values than VP storage. Both superchilled MP-HiOx systems exerted the best preservation for DC beef with lower bacterial counts and TVB-N values among the packaging types, in which the display-life was prolonged to 14 days after 21-days storage. Despite the levels of CO2 influenced microbiota dynamics during anoxic storage, Carnobacterium finally became the predominant bacteria under HiOx-MAP.

Effects of grape seed extract on meat color and premature browning of meat patties in high-oxygen packaging

This study investigated the effects of grape seed extract (GSE) on fresh and cooked meat color and premature browning (PMB) in ground meat patties (85% beef and 15% pork back fat) packaged under high-oxygen modified atmospheres (HiOx-MAP). The GSE was added to patties at concentrations of 0, 0.10, 0.25, 0.50 and 0.75 g kg−1. This study evaluated the surface color, pH, lipid oxidation, and total viable counts (TVC) of raw patties, and the internal color and pH of patties cooked to a temperature of 66 or 71°C over 10-day storage at 4°C. Compared with the control (0 g kg−1 GSE), GSE improved the color stability (P<0.05) and significantly inhibited the lipid and myoglobin oxidation of raw patties from day 5 to 10, but GSE had no effect (P>0.05) on TVC. Patties containing 0.50 and 0.75 g kg−1 GSE cooked to 66°C exhibited greater (P<0.05) interior redness than the control and reduced the PMB of cooked patties in the late storage stage. These results suggested that 0.50 and 0.75 g kg−1 GSE can improve fresh meat color and minimize PMB of HiOx-MAP patties.

Investigation of the relationship between microbiota dynamics and volatile changes in chilled beef steaks held under high-oxygen packaging enriched in carbon dioxide

Carbon dioxide (CO2) plays an important bacteriostatic role in high-oxygen modified atmosphere packaging (HiOx-MAP). This study aimed to explore the influence of CO2 on the volatile organic compounds (VOCs) profile in HiOx-MAP beef steaks and assess the changes in VOCs associated with microbiota dynamics during 20-days of chilled storage. Compared to control MAP (CMAP: 50% O2/50% N2), CO2-enriched MAP (TMAP: 50% O2/40% CO2/10% N2) rendered steaks with desirable appearance and odor freshness during storage through inhibiting bacterial growth and reducing the accumulation of acetoin, 2-ethyl-1-hexanol, 1,3-butanediol, diacetyl and 2-heptanone (P < 0.05). 1-Octen-3-ol and 2-ethyl-1-hexanol were main VOCs in TMAP steaks and were positively related to Brochothrix thermosphacta levels. Acetoin and 2-ethyl-1-hexanol could be used as potential spoilage indicators in CMAP steaks, which were positively related to B. thermosphacta and Pseudomonas levels. Overall, the desirable odor freshness of TMAP steaks was mainly attributed to the CO2-inhibitory effect on the off-odor VOCs production correlated with B. thermosphacta, Pseudomonas and Serratia growth.

High Oxygen Packaging of Atlantic Cod Fillets Inhibits Known Spoilage Organisms, but Sensory Quality Is Not Improved Due to the Growth of Carnobacterium/Carnobacteriaceae.

Improved quality control and prolonged shelf life are important actions in preventing food waste. To get an overview of the bacterial diversity of fillets from live stored mature Atlantic cod, bacterial isolates were identified before and after storage (air and vacuum) and freezing/thawing. Based on the load of dominating bacteria, the effect of different packaging methods and a short freezing/thawing process on prolonged shelf-life was evaluated (total viable counts, bacteriota, sensory attributes, and volatile components). Hand filleted (strict hygiene) cod fillets had a low initial bacterial load dominated by the spoilage organism Photobacterium, whereas industrially produced fillets had higher bacterial loads and diversity (Pseudomonas, Arthrobacter, Psychrobacter, Shewanella). The identified bacteria after storage in vacuum or air were similar to the initially identified bacteria. Bacteriota analysis showed that a short time freezing/thawing process reduced Photobacterium while modified atmosphere packaging (MAP; 60% CO2/40% O2 or 60% CO2/40% N2) inhibited the growth of important spoilage bacteria (Photobacterium, Shewanella, Pseudomonas) and allowed the growth of Carnobacterium/Carnobacteriaceae and Acinetobacter. Despite being dominated by Photobacterium, fresh fillets stored in MAP 60% CO2/40% N2 demonstrated better sensory quality after 13 days of storage than fillets stored in MAP 60% CO2/40% O2 (dominated by Carnobacterium/Carnobacteriaceae). Carnobacterium spp. or other members of Carnobacteriaceae may therefore be potential spoilage organisms in cod when other spoilage bacteria are reduced or inhibited.

Effectiveness of Sprayed Bioactive Fruit Extracts in Counteracting Protein Oxidation in Lamb Cutlets Subjected to a High-Oxygen MAP.

High-oxygen packaging atmosphere (High-Ox-MAP) promotes meat protein oxidation and leads to texture deterioration. This study was conceived to assess the extent to which sprayed fruit extracts could inhibit the oxidative damage to proteins in lamb cutlets subjected to High-Ox-MAP (10 days/4 °C) and subsequent roasting (10 min/180 °C). Extracts from oaknut (Quercus ilex subsp. ballota; QI), rose hips (Rosa canina L.; RC), common hawthorn (Crataegus monogyna Jacq.; CM) and strawberry tree (Arbutus unedo L.; AU) were characterized for bioactive compounds (phenolic subclasses, tocopherols and ascorbic acid) and in vitro bioactivities. While the four fruits showed relevant antioxidant potential, CM had the highest phenolics and tocopherol content and that was reflected in efficient antiradical activity. The in vitro activity of this fruit to inhibit meat protein oxidation was, however, lower than that displayed by the other fruits. Taking the results altogether, CM was also found to be most efficient in protecting lamb cutlets from lipid oxidation. All fruits were able to inhibit thiols oxidation except RC, which seemed to reduce protein thiols. Among fruits, QI was the most efficient in protecting lamb cutlets against protein carbonylation as a plausible involvement of ellagitannins. The inhibition of protein oxidation by QI was reflected in significantly lower instrumental hardness in cooked lamb cutlets. Spraying lamb cutlets with extracts from QI, RC and CM improved consumers’ purchase intention after chilled storage. This antioxidant strategy seems to be a feasible and efficient solution to the pro-oxidative effects caused by High-Ox-MAP in red meat.

Application of modified atmosphere and active packaging for oyster mushroom (Pleurotus ostreatus)

Abstract This research investigated the effect of combining modified atmosphere packaging with bilayer active packaging (MAP + BL) on the shelf life of oyster mushroom (Pleurotus ostreatus). The BL active packaging consisted of gelatin with pomegranate peel powder (PPP) coated on the polyethylene (PE) film (gelatin + PPP/PE). Pouches of single layer (SL) of PE was used for MAP without active function (MAP + SL). Three different conditions of MAP were used i.e. high oxygen packaging (HOP), medium oxygen packaging (MOP) and low oxygen packaging (LOP). Mushroom packaged with atmospheric air (ATM) was used as control. The mushroom packed in MOP with active layer successfully increased the shelf-life of mushroom up to 11 days as compared to the control (3 days). Generally, mushroom in MAP + BL presented better results in all analyses as compared to MAP + SL. Oyster mushrooms packaged in MOP + BL showed the lowest weight loss as only 0.60 % decreased in weight was recorded throughout the storage time. Despite the lowest (p

272 High oxygen packaging is detrimental to beef flavor and tenderness

Abstract This study determined the influence of packaging and muscle on beef flavor and tenderness. Strip loins and top sirloin butts (n = 20/subprimal) from USDA Low Choice carcasses were fabricated into 2.54 cm steaks (Longissimus lumborum and Gluteus medius) at 7 d postmortem. Steaks were randomly assigned to packaging treatments: carbon monoxide motherbag (CO), high oxygen modified atmosphere packaging (HIOX), polyvinyl overwrap (OW) and rollstock (ROLL) and aged for 14 d in dark storage. Steaks in OW were vacuum packaged during aging, then overwrapped for display. Steaks were placed in coffin-style retail display for 48-h under fluorescent lighting. For trained panels and Warner-Bratzler shear force (WBSF), steaks were cooked to 71℃ using clamshell grills. Seven trained panelists rated steaks for beef flavor identity, brown/roasted, bloody/serumy, fat-like, liver-like, oxidized, fishy, buttery, umami, bitter, sour, overall juiciness, and overall tenderness. Data was analyzed as a 2 × 4 factorial design, with packaging, muscle, and their interaction as fixed effects, peak temperature as a covariate, and collection, round, and panel as random effects. No interactions (P ≥ 0.103) or muscle main effects (P ≥ 0.063) were observed. Packaging impacted all traits (P ≤ 0.048), except for fat-like (P = 0.387), liver-like (P = 0.950), and salty (P = 0.357). Steaks from HIOX packaging were rated the lowest for positive flavor attributes and rated highest for negative flavor attributes. Conversely, OW and ROLL steaks produced the greatest positive flavor attributes in comparison with HIOX. Overwrap and ROLL steaks were juicier and more tender than HIOX steaks (P &amp;lt; 0.05). High oxygen steaks exhibited the highest WBSF value compared to all other treatments (P &amp;lt; 0.05). These results indicate HIOX packaging has detrimental effects on flavor and tenderness. Steaks should be stored and aged in anerobic packaging to maintain optimum levels of tenderness and flavor.

Consumer Liking and Descriptive Flavor Attributes of M. Longissimus Lumborum and M. Gluteus Medius Beef Steaks Held in Varied Packaging Systems

Sensory evaluation was conducted to investigate the impact of packaging system and muscle type on beef flavor. Beef M. Longissimus lumborum (LL) and M. Gluteus medius (GM) steaks were produced from vacuum packaged subprimals at 14 d postmortem. Steaks were placed in various packaging types and held for 7 d prior to 48 h of retail display under continuous fluorescent lighting. Packaging types included: high-oxygen modified atmosphere lidded trays (80% O2/20% CO2, HIOX), carbon monoxide modified atmosphere lidded trays (0.4% CO/30% CO2/69.6%N2, CO), rollstock (forming/non-forming films, ROLL), vacuum packaging (stored in darkness, VAC), and traditional overwrap (foam trays wrapped with polyvinyl chloride film immediately before display, OW). Steaks were evaluated after cooking by consumer panelists and a trained descriptive attribute panel. For consumer evaluation, a muscle × package type interaction (P = 0.040) occurred for juiciness. Overall liking, tenderness, and liking of flavor were influenced (P ≤ 0.003) by package type. Overall liking, liking of flavor, and tenderness of HIOX was lower (P &lt; 0.05) than all other package types. Additionally, package type impacted (P ≤ 0.030) overall, flavor, and tenderness acceptability. Overall and flavor acceptability was the lowest (P &lt; 0.05) for the HIOX treatment. From trained panel attribute evaluation, muscle × package type interactions were detected (P ≤ 0.021) for brown/roasted, bloody/serumy, and juiciness. Juiciness was the least (P &lt; 0.05) desirable for GM HIOX compared to all other muscle and package type combinations. Steaks from HIOX packages had the highest (P &lt; 0.05) ratings for oxidized and cardboardy, and were rated lowest (P &lt; 0.05) in beef flavor ID and umami compared with all other package types. The LL had greater (P &lt; 0.05) beef flavor ID, fat-like, umami, sweet, and overall tenderness ratings than the GM. The GM was more (P &lt; 0.05) liver-like and oxidized compared with the LL. These data indicate a high oxygen packaging environment has the potential to accentuate negative descriptive sensory attributes and lower consumer sensory scores, while diminishing palatability in both muscles.

Proteomic analysis to investigate color changes of chilled beef longissimus steaks held under carbon monoxide and high oxygen packaging

This study investigated the proteome basis for color stability variations in beef steaks packaged under two modified atmosphere packaging (MAP) methods: HiOx-MAP (80% O2/20% CO2) and CO-MAP (0.4% CO/30% CO2/69.6% N2) during 15 days of storage. The color stability, pH, and sarcoplasmic proteome analysis of steaks were evaluated on days 0, 5, 10 and 15 of storage. Proteomic results revealed that the differential expression of the sarcoplasmic proteome during storage contributed to the variations in meat color stability between the two MAP methods. Compared with HiOx-MAP steaks, some glycolytic and energy metabolic enzymes important in NADH regeneration and antioxidant processes, antioxidant peroxiredoxins (thioredoxin-dependent peroxide reductase, peroxiredoxin-2, peroxiredoxin-6) and protein DJ-1 were more abundant in CO-MAP steaks. The over-expression of these proteins could induce CO-MAP steaks to maintain high levels of metmyoglobin reducing activity and oxygen consumption rate, resulting in CO-MAP steaks exhibiting better color stability than HiOx-MAP steaks during storage.

53 Impact of Packaging Types on Cooked Beef Volatile Flavor Compounds.

The objective of this study was to evaluate the impact of packaging type and muscle on beef volatile flavor compounds produced from grilling. Gluteus medius (GM) and Longissimus lumborum (LL) steaks were fabricated into 2.54 cm steaks and packaged in carbon monoxide modified atmosphere (CO), high oxygen (HIOX), polyvinyl chloride overwrap (OW), rollstock (ROLL), or vacuum (VAC) packaging and held for 7 days in dark storage. Steaks were then placed in retail coffin cases for 48 hours, except for VAC, which were held in darkness. Following the 48 hours, steaks were vacuum packaged and frozen at -20℃ until volatile compound analysis. Steaks were cooked to a medium degree of doneness (71℃) prior to analysis. Compounds evaluated were derived from various flavor development pathways, including Maillard reaction products and lipid derived compounds. Interactions between packaging type and muscle (P < 0.05) were observed for 2,3-pentanedione and 1-pentanol - two lipid derived compounds. Packaging significantly impacted lipid degradation products, as HIOX packaging possessed the greatest amount (P < 0.05) of 1-octen-3-ol, 1-octanol, dodecanal, nonane, pentane, tetradecane, 2-pentylfuran, 2-heptanone, 1-octene, and hexanoic acid, methyl ester when compared to all other packaging schemes. Contrastingly, ROLL packaging exhibited the greatest amount (P < 0.05) of 2-methy1-1-pentene and 2,4-dimethyl-1-heptene. For Maillard reaction products, HIOX possessed a greater amount of phenylacetaldehyde (P < 0.05) than ROLL and VAC treatments, but was similar (P > 0.05) to OW and CO. Dimethyl sulfide was present in the greatest amount (P < 0.05) in ROLL, VAC, and CO than HIOX and OW, which were similar (P > 0.05). When evaluating the impact of muscle on Maillard reaction products, LL steaks produced a greater amount (P < 0.05) of the Strecker aldehydes 3-methylbutanal and 2-methylbutanal than GM steaks. Similarly, LL steaks also produced a greater amount (P < 0.05) of methyl pyrazine, 2,5-dimethylpyrazine, and dimethyl sulfone. Contrastingly, GM steaks produced a greater amount (P < 0.05) of 2,3-butanedione, 3-hydroxy-2-butanone, and dimethyl sulfide than LL steaks when cooked. Within lipid derived compounds, LL steaks possessed a greater amount (P < 0.05) of ethanol and butryrolactone. However, GM steaks exhibited a greater amount (P < 0.05) of 2,3-butanediol and octanoic acid, which are indicators of lipid oxidation. These results suggest steaks in HIOX packaging undergo a greater amount of lipid oxidation in comparison to other packaging types. This could lead to detrimental effects of beef flavor when purchased by consumers.

Carbon monoxide packaging shows the same color improvement for dark cutting beef as high oxygen packaging

In this study, carbon monoxide (CO) modified atmosphere packaging (MAP) was used to increase redness (a*) and lightness (L*) values of dark cutting beef (ultimate pH (pHu)≥6.10), compared to normal pHu beef and intermediate pHu beef (pH: 5.40–5.79; pH: 5.80–6.09, respectively) during 20 d chilled storage. Compared with HiOx-MAP, CO-MAP exhibited similar color improvement effects (increased L*, a*, b* values) for all pHu beef groupings. The metmyoglobin (MetMb) content was lower under CO-MAP than that of HiOx-MAP in normal pHu beef, but opposite effects were observed in dark, high pH beef. This result could not be explained by MetMb reducing ability (MRA) and lipid oxidation, as both parameters were higher in CO-MAP beef than either normal or high pHu beef, compared with HiOx-MAP. In conclusion, CO-MAP was effective to maintain the cherry red color for dark cutting beef, but the color improvement mechanisms might be different with HiOx packaging methods.

The Effect of Film Type and Modified Atmosphere Packaging with Different Initial GAS Composition on the Shelf Life of White Mushrooms (Agaricus bisporusL.)

The aim of the study was to evaluate the effect of MAP and film thickness on Agaricus bisporus quality. Three initial gas compositions: high oxygen packaging (100% of O2); medium oxygen packaging (50% O2, 50% N2); low oxygen packaging (5% O2, 5% CO2, 90% N2) and two types of polyethylene films of 54 and 39 µm thickness were used. The samples were stored at 4 ± 1C for 14 days. The films and MAP had a significant effect on color and weight loss of the mushrooms. In the case of texture, the gas composition alone exerts a significant effect. The optimal conditions for prolonging the shelf life of mushrooms were found for packaging with medium oxygen level and film of higher permeability. In optimal conditions, mushrooms were characterized by lightness of 93 and 85, and a browning index of 11 and 23 in 0 and 14 days of storage, respectively. Practical Application White button mushrooms are highly perishable. The average storage time of fresh mushrooms does not exceed 4 days. There is a pressing need for effective methods to extend the shelf life of these mushrooms. According to the presented results, it is possible to maintain the product visually acceptable up to 14 days for mushrooms packed with the usage of a 39 µm thick film type and modified atmosphere with a medium level of oxygen (50%).

Effects of High Oxygen Packaging on Tenderness and Water Holding Capacity of Pork Through Protein Oxidation

The objective of this study was to investigate the biochemical difference of pork under high oxygen modified atmosphere packaging and their contribution to meat tenderness and water holding capacity of pork during postmortem storage. Twelve longissimus dorsi muscles were randomly assigned to either high oxygen modified atmosphere packaging or vacuum packaging and stored for 1, 4, and 6 days at 4 °C. The carbonyl content, protein surface hydrophobicity, protein solubility, calpain activity, desmin degradation, tenderness, and water loss of pork were determined. Results showed that carbonyl content, protein surface hydrophobicity, and protein solubility were significantly affected (P 0.05). Samples from high oxygen modified atmosphere packaging at 1 day showed greater intensity of intact 80 KDa calpain and lower intensity of autolyzed 76 KDa calpain product compared to samples from vacuum packaging (P 0.05). Higher intensity of intact desmin was observed in samples from high oxygen modified atmosphere packaging than vacuum packaging samples from 1 day of postmortem storage. Both packaging method and storage time showed significant effects (P < 0.05) on tenderness and water loss of pork muscle during postmortem storage. Changes in protein oxidation, calpain activation, and protein proteolysis of postmortem pork under high oxygen modified atmosphere packaging could help to explain decreased meat tenderness and increased centrifuge loss of pork.

Effect of active modified atmosphere packaging with different initial gas compositions on nutritional compounds of shiitake mushrooms (Lentinus edodes)

The effect of active modified atmosphere packaging with different initial gas compositions on fresh shiitake mushrooms was investigated. Shiitake mushrooms were packaged under each of the following conditions: (1) high oxygen packaging (HOP), 100% oxygen initially; (2) medium oxygen packaging (MOP), 50% O2 and balanced with N2 initially; (3) low oxygen packaging (LOP), 3% O2/5% CO2, balanced with N2 initially. Passive modified atmosphere packaging with air inside initially (AIR) was used as the control treatment. All the packaged samples were stored at 10°C with 90% RH for 7 days. During storage, gas compositions, electrolyte leakage, crude water-soluble polysaccharides, total phenolic content and free amino acid content were determined. The results showed that ethanol release was high in LOP and AIR but retarded in MOP and HOP. No packaging could prevent the decrease in polysaccharide content decreasing. Both the active and passive modified atmosphere packaging maintained the color and integrity of the mushrooms. The active modified atmosphere packaging had a significant effect on the increase of total phenolic content and total amount of free amino acids. LOP had a harmful impact on mushrooms with high levels of electrolyte leakage. In conclusion, HOP and MOP had a better effect on maintaining the nutritional compounds of shiitake mushrooms.

Potential mechanisms of carbon monoxide and high oxygen packaging in maintaining color stability of different bovine muscles

The objectives were to compare the effects of packaging methods on color stability, metmyoglobin-reducing-activity (MRA), total-reducing-activity and NADH concentration of different bovine muscles and to explore potential mechanisms in the enhanced color stability by carbon monoxide modified atmosphere packaging (CO-MAP, 0.4% CO/30% CO2/69.6% N2). Steaks from longissimus lumborum (LL), psoas major (PM) and longissimus thoracis (LT) packaged in CO-MAP, high-oxygen modified atmosphere packaging (HiOx-MAP, 80% O2/20% CO2) or vacuum packaging were stored for 0day, 4days, 9days, and 14days or stored for 9days then displayed in air for 0day, 1day, or 3days. The CO-MAP significantly increased red color stability of all muscles, and especially for PM. The PM and LT were more red than LL in CO-MAP, whereas PM had lowest redness in HiOx-MAP. The content of MetMb in CO-MAP was lower than in HiOx-MAP. Steaks in CO-MAP maintained a higher MRA compared with those in HiOx-MAP during storage. After opening packages, the red color of steaks in CO-MAP deteriorated more slowly compared with that of steaks in HiOx-MAP.

Spatial and temporal mass spectrometric profiling and imaging of lipid degradation in bovine M. longissimus dorsi lumborum

Lipid oxidation plays a critical role in the quality of meat and meat products; however, lipid degradation is generally evaluated at a holistic level, without attention to spatial distribution. Marker lipids were selected based on their relative abundance and characteristic MS fragmentation patterns (10 phospholipids, 2 triglycerides, and cholesterol). These markers were subsequently utilised for temporal and spatial profiling of lipid degradation in bovine M. longissimus dorsi lumborum steaks subjected to high (packaged in 80% O2/20% CO2 modified atmosphere), atmospheric (oxygen permeable film) and ultra-low (vacuum-packaged) oxygen packaging during storage through matrix-assisted laser desorption/ionisation time-of-flight/time-of-flight (MALDI–TOF/TOF) mass spectrometric imaging. Interestingly, markers showed highly contrasting effects in terms of their oxidative stability over time. The relative abundance of phophatidylcholines generally declined rapidly under high oxygen conditions. In contrast, PC 18:1/18:0 showed high relatively stability to oxidation. Cholesterol also displayed high relative stability. Overall, high oxygen packing was found to result in rapid lipid degradation, while vacuum-packaging significantly mitigated lipid degradation. Oxidative degradation profiles were spatially heterogeneous across meat sub-samples and differences were also observed from the centre and edge of the steaks. This new approach to tracking lipid degradation directly from meat samples offers increasingly precise tracking of modification in meat and other foods.

Effect of High-Oxygen Packaging on Respiratory Physiology and Sensorial Qualities of Fresh Shiitake Mushrooms (Lentinus edodes)

&lt;p&gt;In this research, the effect of high-oxygen packaging (HOP) with initial 80% and 100% oxygen on fresh shiitake mushrooms was studied. Initial air in package was the control treatment. All the samples were stored at 10 °C with RH 90% for 9 days. Respiration rate, hardness, TSS, and color were determined, and sensory quality was evaluated during the storage. Results indicated that high-oxygen packaging retarded the anaerobic metabolism occurrence and HOP with initial 100% oxygen could maintain the lightness of shitake mushroom better than 80% oxygen. Hardness and TSS did not show significant difference between high-oxygen packaging and control treatment. However, neither initial 100% O&lt;sub&gt;2&lt;/sub&gt; nor 80% O&lt;sub&gt;2&lt;/sub&gt; could reduce the respiration rate of fresh shiitake mushroom. Sensory quality especially the aroma, cap color and gill color of fresh shiitake mushroom could be better maintained in high-oxygen packaging than control treatment. The acceptability of the shiitake mushrooms after storage was the highest in HOP with initial 100% oxygen. In conclusion, high-oxygen packaging especially with initial 100% oxygen showed the obvious effect maintaining the sensory quality of fresh shiitake mushrooms although it could not reduce the respiration rate at 10 °C.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;

Influence of an antioxidant on the shelf-life and quality of ground beef stored in a high-oxygen master package prior to display

Influence of an antioxidant on the shelf-life and quality of ground beef stored in a high-oxygen master package prior to display