Effect of Skin Wine Pomace and Sulfite on Protein Oxidation in Beef Patties During High Oxygen Atmosphere Storage

Meat storage in high oxygen atmosphere has been reported to induce protein oxidation reactions decreasing meat quality. The incorporation of antioxidants has been proposed to reduce the extent of these reactions. In this study, the ability of red and white skin wine pomaces as well as sulfites to inhibit protein oxidation were tested in beef patties stored for up to 15 days at 4 °C in a high oxygen atmosphere (70 % O2 and 30 % CO2). SO2 (300 ppm) effectively protected against protein oxidation measured as radical formation by electron spin resonance (ESR) spectroscopy, as thiol loss by the DTNB assay and as myosin heavy chain (MHC) disulfide crosslinking by SDS-PAGE. Pomace from red wine production with a total phenol of 9.9 mg gallic acid equivalent/g protected against protein radical formation and against MHC crosslinking, but not against thiol loss by addition of 2.0 % (w/w) to the beef patties. Pomace from white wine production with a total phenol of 4.0 mg gallic acid equivalent/g only protected against MHC cross-linking. For both types of wine pomace, protein modifications not seen for sulfite addition were observed and were proposed to involve covalent phenol addition to proteins. Red wine pomace may be an alternative to sulfite as a meat additive for protection of beef patties against protein oxidation.Autonomous Government of Castilla y León through the research projects (BU268A11-2 and BU282U13) and the Danish Council for Independent Research |Technology and Production within the Danish Agency for Science Technology and Innovation for granting the project entitled: BAntioxidant mechanisms of natural phenolic compounds against protein cross-link formation in meat and meat systems^ (11-117033)

Adaptation and Validation of QUick, Easy, New, CHEap, and Reproducible (QUENCHER) Antioxidant Capacity Assays in Model Products Obtained from Residual Wine Pomace

Evaluation of the total antioxidant capacity of solid matrices without extraction steps is a very interesting alternative for food researchers and also for food industries. These methodologies have been denominated QUENCHER from QUick, Easy, New, CHEap, and Reproducible assays. To demonstrate and highlight the validity of QUENCHER (Q) methods, values of Q-method validation were showed for the first time, and they were tested with products of well-known different chemical properties. Furthermore, new QUENCHER assays to measure scavenging capacity against superoxide, hydroxyl, and lipid peroxyl radicals were developed. Calibration models showed good linearity (R2 > 0.995), proportionality and precision (CV < 6.5%), and acceptable detection limits (<20.4 nmol Trolox equiv). The presence of ethanol in the reaction medium gave antioxidant capacity values significantly different from those obtained with water. The dilution of samples with powdered cellulose was discouraged because possible interferences with some of the matrices analyzed may take place.The autonomous government of Castilla y León (Project BU268A11-2

Dietary citrus pulp improves protein stability in lamb meat stored under aerobic conditions

The antioxidant effects of dried citrus pulp on proteins in lamb meat, when used as a replacement of concentrate in the feed, was studied using meat from 26 male Comisana lambs. The lambs of age 90 days had been grouped randomly to receive one of the three dietary treatments: (1) commercial concentrate with 60% barley (Control, n = 8), (2) concentrate with 35% barley and 24% citrus pulp (Cp24, n = 9), or (3) concentrate with 23% barley and 35% citrus pulp (Cp35, n = 9). Slices from the longissimus thoracis et lomborum muscle were packed aerobically and stored for up to 6 days at 4°C in the dark. The citrus pulp groups, Cp24 and Cp35, significantly decreased protein radicals and carbonyls, and preserved more thiols within six days of storage compared to the Control group. The citrus pulp groups significantly slowed down the rate of protein oxidation, indicating that dietary citrus pulp reduced oxidative changes in meat proteins

Fatty acids and oxidative stability of meat from lambs fed carob-containing diets

Male Comisana lambs were individually stalled and, for 56 days, were fed concentrates with 60% barley (n = 8 lambs), or concentrates in which barley was partially replaced by 24% or 35% carob pulp (n = 9 lambs in each group). The intramuscular fatty acids were analyzed and the color stability, lipid and protein oxidation were measured in fresh meat overwrapped with polyvinyl chloride film at 0, 3 or 6 days of storage at 4 °C in the dark. Carob pulp increased the concentration of polyunsaturated fatty acids (PUFA) in muscle, including the rumenic acid (P < 0.01), and reduced the saturated fatty acids (P < 0.01) and the n-6/n-3 PUFA ratio (P = 0.01). The meat did not undergo extensive oxidative deterioration and the diet did not affect the oxidative stability parameters. Therefore, carob in lamb diet could increase PUFA in muscle without compromising meat oxidative stability

Oxidative stability of refrigerated fish pates containing loquat seed extract

This study investigated the effects of hydroethanolic E. japonica seed extracts (EJSE) as inhibitors of lipid and protein oxidation on fish pates subjected to refrigerated storage. Five fish pate formulations were developed. These formulations included two control pates (water-control and ascorbic acid-control) and three pates with added EJSE (0.1, 0.2 and 0.4g of seed 100g-1 product, equivalent to 3.4, 6.8 or 13.6mg phenolic compounds kg-1 product), which were then stored under refrigeration for 35 days. Conjugated dienes (CD) and peroxide (PV) values increased along with the storage time; however, these values decreased and were similar among all samples at the end of 35 days of analysis (P<0.05). However, the thiobarbituric acid reactive substances levels (TBARS) did not change along the storage and were not affected by the EJSE. Additionally, there was a linear increase in the protein carbonyl content of fish pates over the storage period (P<0.05), but no effect of EJSE on protein oxidation. The results show that, at the concentrations evaluated, hydroethanolic E. japonica seed extract was unable to inhibit or reduce lipid and protein oxidation in fish pates, but the observed phenolic content emphasizes the need for further studies on the wastes of this fruit