RESUMEN
Lipid oxidation is the most crucial quality parameter in foods. Many methods were developed to determine the level of oxidation and antioxidant activity. This review compares the methods used to determine lipid oxidation and antioxidant capacity in foods. Lipid oxidation methods developed are based on the direct or indirect measurement of produced primary or secondary oxidation substances. Peroxide values and conjugated diene methods determine the primary oxidative products of lipid oxidation and are commonly used for plant oils and high-fat products. 2-Thiobarbituric acid-reactive substances and chromatographic methods are used to determine the secondary products of oxidation and are suitable for meat and meat-based products. The fluorometric and sensory analyses are indirect methods. The antioxidant capacity of additives is determined indirectly using the lipid oxidation methods mentioned above or directly based on the free-radical scavenging activity of the antioxidant compounds. Each lipid oxidation and antioxidant capacity methods use different approaches, and one method cannot be used for all foods. Therefore, selecting proper methods for specific foods is essential for accurately evaluating lipid oxidation or antioxidant capacity.
RESUMEN
The supplementation effects of sea tangle powders were determined for the meat quality in Korean native black goats. A total 90 castrated male black goats at 3-month age were divided into 3 dietary treatment groups: control (basal diet + mineral block), T1 (0.3% sea tangle feeding with the basal diet), T2 (0.9% sea tangle feeding with the basal diet). At 9-months feeding, 10 goats per treatment group were slaughtered, and the longissimus dorsi muscle samples were vacuum-packed, and subsequently analyzed for physicochemical evaluations. Analysis revealed decrease in the shear force and TBARS values of meat in the sea tangle dietary groups (p < 0.05). The T2 group exhibited increased levels of unsaturated fatty acids such as C16:1, C18:1, C18:2, and C20:4 (p < 0.05). The content of free amino acids with desirable taste such as aspartic acid, glutamic acid, glycine, histidine, and serine were higher in T2, whereas alanine content was higher in both sea tangle dietary groups, as compared to control (p < 0.05). These data indicate that feeding dietary sea tangle as an alternative mineral source results in an improvement in the physicochemical profiles of goat meat.
RESUMEN
Irradiated raw ground beef had lower a*- and b*-values than nonirradiated ones regardless of garlic or onion treatment at 0 d. Irradiation increased TBARS values of control ground beef, but addition of 0.5% onion or 0.1% garlic+0.5% onion reduced oxidative changes during storage. Addition of garlic or onion greatly increased the amounts of sulfur compounds, but the increase was greater with garlic. With irradiation, the profiles and amounts of S-volatiles in raw ground beef changed significantly. However, the intensity of irradiation aroma in irradiated raw ground beef with garlic or onion was similar to that of the nonirradiated control. This indicated that some of the sulfur compounds unique to garlic or onion interacted with common sulfur compounds detected in irradiated meat and masked or changed the odor characteristics of irradiated raw ground beef. It was concluded that >0.5% onion or <0.01% garlic would be needed to mask or prevent irradiation aroma in irradiated raw ground beef.