EFFECT OF DEEP-FAT FRYING ON CANOLA OIL, PALMOLEIN AND SUNFLOWER OIL BLENDS: B) BIOLOGICALAND NUTRITIONAL STUDIES

Abstract

Canola oil (CO) is very high in healthy unsaturated fatty acids. It is higher in the omega-3 fatty acid alpha-linolenic acid than any of other oil except flaxseed oil. Because of its light flavor, high smoke point and smooth texture, canola oil is one of the most versatile cooking oils. Oil blending is one way of the most suitable technology to overcome the problem of poor stability of canola oil. It was blend with sunflower oil (SF)and palm olein (PO) to evaluate technological and nutritional qualities. This study was conducted to assess the effects of long-term intake of different fresh edible canola oils, their blends and those frying oils, selected due to their common use in human nutrition. Sixteen groups of (50-70g) albino male rats (n = 5), were fed for 90 days on different fresh and frying oils which drown from different frying cycles of potato chips up to 30th frying. The experiment period was divided into two durations 45- days for each. Blood serum analysis for rat groups were showed; a significant increases in liver, kidney and heart functions consider to 1st experimental duration as compared with the control group which fed on corn oil, While these functions were non-significant difference in the 2nd experimental duration. Serum lipid profile and Atherogenic Index (AI) were recorded a significant different among all groups as compared with the control group (G1) during 1stexperimental duration. However, HDL-C was significant decreased in the 1st duration than that in the 2nd. Otherwise, canola oil in the diets could be increase the HDL level than that in rats group fed on corn oil. A distinct lowering in TG level was recorded among rat groups fed on diets of CO+PO (G12:G16) in the 1st duration. Internal antioxidant of serum coenzyme Q10 was found to decline among later groups fed on frying oils 30th (G6, G11 and G16) ranges ˂ 70mmol/ml. A blood lymphocyte percentage recorded diminution at 8% among groups which fed on fresh CO + PO (G12) and used frying CO + PO (G13, G14 and G16) oils than other groups as well as the control group G1 through 1st duration. Histological examination for liver, kidney, heart, intestinal and testes tissue of rats were investigated. Most of groups exhibited different histological alteration, these alerts were sever along the later groups fed on 20th and 30th frying cycles oil. Depend on this study, canola oil and palm olein in blend can be used to improve the health status of such fried foods and their oils up to 10th frying cycles.