Control of Lipid oxidation

ABSTRACTOxidative rancidity in fresh and stored ground beef samples was measured using a thiobarbituric acid (TBA) assay with antioxidant protection. The independent variables were fat concentration (15 or 30%), package type (polyethylene or vacuum‐packaged), freezer storage temperature (‐12.2°, ‐23.3° or ‐34.4°C) and storage time (4, 8, 12, 16, or 20 weeks). At the end of each storage time samples were thawed and TBA values were determined on the samples before and after cooking. TBA values increased during the first 12 to 16 weeks after which time it decreased for both the cooked and uncooked samples. The higher fat samples, packaged in polyethylene, had higher TBA values for both cooked and uncooked patties. Uncooked patties stored at ‐ 12.2°C had higher TBA values than those stored at ‐23.3°C or ‐34.4°C but cooked sample TBA values showed no dependence on storage temperature.

This study investigated the effect of refined rosemary extract on lipid oxidation in frozen, precooked beef patties (FBP) stored at-18.0C (0.4F) for 12 weeks. Samples were analyzed for peroxide value (PV) levels, 2-thiobarbituric acid (TBA) values and sensory characteristics on 0 day and after 4, 8, and 12 weeks. Samples with rosemary extract showed lower PV and TBA values. Sensory evaluations of precooked patties with rosemary extract were not significantly different in scores on color, smell/odor, appearance, texture and overall acceptability. Samples with refined rosemary extract reported a significantly higher liking score for flavor (P Ͻ 0.05), however, there was no significant correlation between PV and sensory scores and TBA and sensory scores for both frozen, precooked patties with/without the addition of refined rosemary extract.

Oxidation of polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish causes loss of product quality. Oxidative rancidity causes loss of nutritional value and undesirable color changes. Therefore, powerful antioxidant extracts may provide a relatively low cost and natural means to reduce oxidation, resulting in longer, higher quality and higher value shelf life of foods. In this study, we measured synergistic effects of red cabbage antioxidant and vacuum packaging on lipid oxidation in fresh tilapia patties using thiobarbituric acid reactive substances (TBARS) assay, peroxide value (PV), pH and color analysis. Concentrated red cabbage extract was obtained using an efficient freeze/thawed method developed in our laboratory (citation). Fresh tilapia patties were prepared with solutions containing 68 ppm of extract concentrate for each 50 gr of fish patties. Samples were stored for 15 days at refrigeration conditions (4±1°C) and analyzed in...

The effect of milk protein concentrate (MPC) at 0, 2, 4, and 6% on lipid oxidation and volatile formation in frozen stored herring mince (-18°C) was evaluated by analyzing samples at 0, 2, and 4 months for fatty acid composition, volatiles, and thiobarbituric acid reactive substances (TBARS). Sensory evaluation was also conducted to assess the intensity of fishy odor, and the volatiles were analyzed using static headspace gas chromatography-mass spectrometry (SHGC-MS). The addition of 4 and 6% MPC to herring mince resulted in a 33% and 50% reduction of TBARS, respectively, at month 4 and lessened the intensity of fishy odor throughout storage. However, MPC did not protect fatty acids from enzymatic degradation unless it was added immediately after mincing. Volatile analysis using SHGC-MS showed that 4% MPC was able to reduce headspace volatiles associated with fishy odor. MPC is most effective for reducing 4-heptenal, 3-methyl-1-butanol, 2-hexenal, and 1-penten-3-ol, which are known to be potent odorants associated with lipid oxidation.

Oxidation of polyunsaturated fatty acids (PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in fish causes loss of product quality. Oxidative rancidity causes loss of nutritional value and undesirable color changes. Therefore, powerful antioxidant extracts may provide a relatively low cost and natural means to reduce oxidation, resulting in longer, higher quality and higher value shelf life of foods. In this study, we measured synergistic effects of red cabbage antioxidant and vacuum packaging on lipid oxidation in fresh tilapia patties using thiobarbituric acid reactive substances (TBARS) assay, peroxide value (PV), pH and color analysis. Concentrated red cabbage extract was obtained using an efficient freeze/thawed method developed in our laboratory (citation). Fresh tilapia patties were prepared with solutions containing 68 ppm of extract concentrate for each 50 gr of fish patties. Samples were stored for 15 days at refrigeration conditions (4±1°C) and analyzed in...

A BSTRA CT Lipid oxidation is a major cause of deterioration of the quality of stored meat arrd meat products. This review deals with the mechanism and the methods used to follow lipid oxidation, as well as the interaction of lipids/lipid oy~idation products with food components and their possible biological effects. Emphasis is given to the presentation of the anti-and pro-oxidant properties of various compounds and conditions; their relative importance in oxidative rancidity is discussed. MECHANISM OF LIPID OXIDATION A major cause of muscle food quality deterioration is lipid oxidation and the changes associated with it. Lipid oxidation is a rather complex process whereby unsaturated fatty acids reacting with molecular oxygen via a free radical chain mechanism, form fatty acyl hydroperoxides, generally called perox:ides or primary products of the oxidation (Gray, 1978). The primary auto-oxidation is followed by a series of secondary reactions which lead to the degradation of the lipid and the development of oxidative rancidity. The problems associated with lipid oxidation have gained much interest as they relate to flavour deterioration, loss of nutritional value and safety, biological

A BSTRA CT Lipid oxidation is a major cause of deterioration of the quality of stored meat arrd meat products. This review deals with the mechanism and the methods used to follow lipid oxidation, as well as the interaction of lipids/lipid oy~idation products with food components and their possible biological effects. Emphasis is given to the presentation of the anti-and pro-oxidant properties of various compounds and conditions; their relative importance in oxidative rancidity is discussed. MECHANISM OF LIPID OXIDATION A major cause of muscle food quality deterioration is lipid oxidation and the changes associated with it. Lipid oxidation is a rather complex process whereby unsaturated fatty acids reacting with molecular oxygen via a free radical chain mechanism, form fatty acyl hydroperoxides, generally called perox:ides or primary products of the oxidation (Gray, 1978). The primary auto-oxidation is followed by a series of secondary reactions which lead to the degradation of the lipid and the development of oxidative rancidity. The problems associated with lipid oxidation have gained much interest as they relate to flavour deterioration, loss of nutritional value and safety, biological

Lipid oxidation is a major cause of deterioration of the quality of stored meat arrd meat products. This review deals with the mechanism and the methods used to follow lipid oxidation, as well as the interaction of lipids/lipid oy~idation products with food components and their possible biological effects. Emphasis is given to the presentation of the anti-and pro-oxidant properties of various compounds and conditions; their relative importance in oxidative rancidity is discussed.

The changes in tocopherol content of oil used for deep-fat frying of potatoes have been studied. It has been found that cw-tocopherol is lost much faster than p, */-or 6 tocopherol, with a reduction of 50% cY-tocopherol after 4-5 frying operations compared with values of about 7 and 7-8 frying operations for /3and y-tocopherol, respectively, in the absence of added antioxidants. However, the presence of a rosemary extract or ascorbyl palmitate in the frying oil caused a marked reduction in the rate of loss of the tocopherols.

The effect of several commercial antioxidants on lipid oxidation of common carp fillets stored at ∼ 5°C for 16 days was evaluated. Also, different packaging conditions were used to study their effects on lipid oxidation and rancid odor. Antrancine 350 was found to be the best antioxidant in controlling lipid oxidation throughout the refrigerated storage. This antioxidant was highly effective at a concentration of 200 ppm and dipping time of 45 min. Vacuum packaging was more effective (P e 0.05) in retarding oxidative rancidity than was packaging without vacuum. The cooked fillets, packaged either with or without vacuum, had higher (P e 0.05) TBA values than did the uncooked fillets. Also, hot packaging gave better protection against lipid oxidation compared to cold and ambient temperature packaging. The sensory evaluation test revealed that the uncooked fillets stored in nylon-polyester bags was the most acceptable treatment throughout the refrigerated storage, while fillets packaged in polyethylene bags without vacuum were unacceptable by the end of the 16 day storage.

The effect of several commercial antioxidants on lipid oxidation of common carp fillets stored at ∼ 5°C for 16 days was evaluated. Also, different packaging conditions were used to study their effects on lipid oxidation and rancid odor. Antrancine 350 was found to be the best antioxidant in controlling lipid oxidation throughout the refrigerated storage. This antioxidant was highly effective at a concentration of 200 ppm and dipping time of 45 min. Vacuum packaging was more effective (P e 0.05) in retarding oxidative rancidity than was packaging without vacuum. The cooked fillets, packaged either with or without vacuum, had higher (P e 0.05) TBA values than did the uncooked fillets. Also, hot packaging gave better protection against lipid oxidation compared to cold and ambient temperature packaging. The sensory evaluation test revealed that the uncooked fillets stored in nylon-polyester bags was the most acceptable treatment throughout the refrigerated storage, while fillets packaged in polyethylene bags without vacuum were unacceptable by the end of the 16 day storage.