A novel body weight-loss promoting oil prepared with vegetable protein

Oxygen content and oxidation in frying oil

The relation between oxygen content and oxidation was investigated in frying oils. When canola oil, a canola-soybean oil blend or a trioctanoylglycerol (glycerol tricaprate) sample were heated with stirring, their dissolved oxygen content decreased abruptly at about 120°C and the carbonyl values (CV) increased gradually with heating and reached values of 6-7 at 180°C in the blended and canola oils, while the CV of trioctanoylglycerol was zero up to 150°C. Probably this abrupt decrease in oxygen content above 120°C can be attributed to the solubility of oxygen in oil rather than because of oxidative reactions. The oxygen content of oil that has been stripped of part of its oxygen, increased at temperatures between 25 and 120°C. In oils that have lost their oxygen by being heated to 180°C, standing at room temperature will slowly restore their oxygen content as the oil cools. Intermittent simple heating of oil promoted oxygen absorbance during cooling periods and standing times, and it resulted in an elevated content of polar compounds (PC). Domestic deep-frying conditions also favor the presence of oxygen in oil below 120°C and during the oil's long standing at room temperature. The oxygen content in oil was low during deep-frying, but oxidation was active at the oil/air interface of bubbles generated by foods being fried. Repeated use of oil at temperatures between 25-180°C resulted in oil with low oxygen values.

Gallic acid glycerol ester promotes weight-loss in rats

Lifestyle-related diseases arise from obesity in 30 - 60% of cases. In recent years, food functions controlling the nutritional physiology of lipids have been a focus of disease prevention. Animal feeding experiments have revealed that esters made from gallic acid (GA) and (-)-epigallo-catechin (EGC) or linoleyl alcohol are more effective in weight-loss promotion and metabolic syndrome management than are intact GA and EGC. In this study, an ester (DOGGA) was chemically synthesized from GA and 1,2-dioleoyl glycerol and its effect was compared to that of octyl gallate (OG) and GA in male Wistar rats fed a powdered standard diet containing 7% frying oil for 12 weeks. Results revealed remarkably low body weight gains and food efficiency ratios in the DOGGA group, and the effects of OG were less pronounced than those of DOGGA. The GA group showed no difference from the control group. In addition, fecal lipid content in the DOGGA group was statistically higher than that in the control group, although organ weights and serum biochemical analyses did not differ between the groups. In conclusion, the data suggested that DOGGA promoted weight-loss more effectively than OG and GA did and that the alcohol moiety of gallate is not necessarily EGC and linoleyl alcohol.

Role of vegetable protein in the preparation of weight loss-promoting oil

We have reported that oil thermally processed with protein promoted safe and steady weight loss in animal experiments. In the present study, an oil for use in weight control was prepared by heating fresh oil with wheat gluten or soybean protein to determine the influence of protein differences on the weight loss-promotion effect. The 2 kinds of oil obtained, which differed neither from commercial fresh oil (starting oil) nor from one another in appearance, chemical properties, and aroma, were mixed (7%) with powdered AIN93G no-fat, defined standard diet and fed to 10-week-old Wistar rats ad libitum. After a 12-week feeding period, the rats were sacrificed to obtain blood and organs. There were no differences in amounts ingested, body weight increases, fecal excretion, organ weights, serum biochemical analyses, contents and fatty acid compositions of lipids of retroperitoneal fat tissue, or organ observations. Aspartate aminotransferase (AST), alanine aminotransferase (AST), and histological analysis supported the safety of the oil. In conclusion, the differences between wheat gluten and soybean protein in amino acid composition, both of the proteins and as free amino acids, were unrelated to the weight loss-promoting effect of the oil. Minor components in the vegetable proteins may have contributed to the effect on body weight.