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Background: Cholesterol oxidation products (COPs) are produced during thermal processing of animal origin foods and are considered to have negative health impacts. The model systems are helpful to understand the impact of various factors on oxidation changes in foods during cooking process. Methods: The study presented herein investigates the effects of pH, presence of unsaturated fatty acids, and heat on the formation of cholesterol oxidation products (COPs). Two model systems were designed to investigate the formation of cholesterol oxidation products in different lipid environments. The cholesterol oxides produced were quantified using gas chromatography. Results: The level of cholesterol oxidation products decreased significantly at higher pH (above 5.8) and shorter heating time (3 h). The presence of unsaturated fatty acids (linoleic and oleic acids) significantly increased the amount of COPs under low-temperature heating conditions (100 °C and 1 h) but did not affect the production of COPs at higher temperature (150 °C). Increasing the temperature to 200 °C significantly increased the amount of COPs during the first hour of heating and this amount decreased upon further heating. The most frequently observed COPs in samples were α-epoxide, 20α-hydroxycholesterol, and 25-hydroxycholesterol. Conclusions: In conclusion, pH below 5.8, presence of unsaturated fatty acid, and high cooking temperature (>150 °C) leads to increased production of cholesterol oxidation products. [ABSTRACT FROM AUTHOR]

Background: Edible coatings have beneficial effect on quality of fish and act as barrier against moisture transfer and uptake of oxygen. Edible coating made up of biodegradable materials is helpful to control the quality deterioration and enhance the shelf life. Methods: The present study was designed to elucidate the effects of whey based protein using two plasticizers i.e. sorbitol and glycerol on oxidative stability and quality characteristics of Rohu (Labeo rohita). Coating solutions were prepared by incorporating whey (8 % protein; w/ w) in distilled water followed addition of sorbitol and glycerol. Dipping method was used to apply coating on fish fillets. The coated fillets were subjected to quality characterictics, pH, color, TBARS, peroxide value, volatile basic nitrogen (TVBN) and sensory evaluation during 40 days of storage. Results: The results showed significant impact on different quality attributes of fish fillets. Highest (TVBN) and TBARS were observed in control samples (T0) (12.60 ± 0.25, mg/100 g, 0.820 ± 0.02 mg MDA/kg) while lowest in T3 coated samples (8.81 ± 0.18 mg/100 g., 0.352 ± 0.01 mg MDA/kg of meat). Moreover, sensorial findings did not showed adverse effects and T3 coated samples were ranked higher by consumers. Conclusion: In conclusion, coating fish with Whey: Glycerol: Sorbitol (1:1:1) in current investigation enhances the storage life and quality of fish fillets. [ABSTRACT FROM AUTHOR]

Background Lipid peroxidation is the cause of declining the meat quality. Natural antioxidants plays a vital role in enhancing the stability and quality of meat. The supplementation of natural antioxidants in feed decreases lipid peroxidation and improves the stability of meat. Methods The present research was conducted to determine the effect of α-lipoic acid, α-tocopherol and wheat germ oil on the status of antioxidants, quality and lipid stability of broiler meat. One day old male broilers were fed with different feeds containing antioxidants i.e. natural (wheat germ oil) and synthetic α-tocopherol and α-lipoic acid during the two experimental years. Results The feed treatments have significant variation on the body weight and feed conversion ratio (FCR) while having no influence on the feed intake. The broilers fed on wheat germ oil (natural α-tocopherol) gained maximum body weight (2451.97 g & 2466.07 g) in the experimental years 2010-11 & 2011-12, respectively. The higher total phenolic contents were found in the broilers fed on wheat germ oil plus α-lipoic acid in breast (162.73±4.8 mg Gallic acid equivalent/100 g & 162.18±4.5 mg Gallic acid equivalent/100 g) and leg (149.67±3.3 mg Gallic acid equivalent/100 g & 146.07±3.2 mg Gallic acid equivalent/100 g) meat during both experimental years. Similar trend was observed for the 2,2-diphenyl-1- picrylhydrazyl (DPPH) and ferric reducing antioxidant power assay (FRAP). The production of malondialdehydes in the breast and leg meat increased with progressive increase in the time period. The deposition of α-tocopherol (AT) and α-lipoic acid (ALA) contents were found to be higher in the broilers fed on wheat germ oil plus α-lipoic acid in breast and leg meat during the both experimental years. Conclusion In conclusion, the combination of wheat germ oil and α-lipoic acid has more beneficial for stability and the quality of the broiler meat and more work should be needed in future for the bio-evaluation of this kind of functional meat in humans [ABSTRACT FROM AUTHOR]

This study was intended to explore the effect of extruded flaxseed meal supplemented diet on broiler growth performance, oxidative stability and organoleptic characteristics of broiler meat and meat products. 120 (day old) broiler chicks were randomly allotted to 12 experimental groups and fed on diets containing extruded flaxseed meal at 0, 5, 10 and 15%. The supplementation of extruded flaxseed in the diet decreases the body weight gain, feed intake and increased feed conversion ratio (FCR) values of broilers. The antioxidant enzymes were strongly influenced by different levels of extruded flaxseed supplementation among treatments. The TBARS assay revealed that maximum malondialdehyde were produced in T3 containing highest extruded flaxseed level (15%) and minimum malondialdehyde were produced in T0 treatment having no extruded flaxseed. The TBARS values ranged from 0.850-2.106 and 0.460-1.052 in leg and breast met respectively. The Free radical scavenging activity varied significantly and DPPH values of breast meat ranged from 20.70% to 39.09% and in leg meat 23.53% to 43.09% respectively. The sensory acceptability of broiler meat nuggets was decreased with the increase in the level of flaxseeds due to the lipid peroxidation of polyunsaturated fatty acids (PUFA) which generated off flavors and bad odors. Feeding extruded flaxseed to chicken through feed strongly inflated the quality and functional properties, fatty acid contents and reduced the oxidative stability of broiler meat and meat products. The present study concludes that up to 10% of flaxseed meal may be used in broiler diet to enhance the omega 3 fatty acids content in the broiler meat. [ABSTRACT FROM AUTHOR]