A comparative study of the nutritive value of thermally oxidized oils

Abstract

Summary Thermal oxidation of corn oil under laboratory conditions, at 200°C., led to the formation of an oil exhibiting definite growth‐depressing action under bothad libitum and paired feeding conditions. Under similar conditions margarine base stock gave only slight growth depression, and none was noted with butter oil. The effect was not a permanent one as animals that were changed to a normal diet quickly recovered and grew to maturity. It appeared that the products formed during the thermal treatment were related to the unsaturated or polyunsaturated portions of the oil. The growth‐depressing effect appeared to be multiple in nature, it had an irritant or diarrhea effect and possibly an enzyme‐inhibiting or vitamin‐destroying effect.

Chemical and nutritional changes in stored herring meal

“…I n addition, there is some evidence of toxicity when oxidized and polymerized oils are given at high levels, oils containing major proportions of polyunsaturated fatty acids being more liable to develop objectionable changes of this type on heating or on storage than edible oils and fats of lower unsaturation. Johnson, Sakuragi & Kummerow (1956) found that the growth-depressing action of thermally oxidized edible oils was related to the decrease in iodine value: maize oil oxidized at 200' until its iodine value had decreased by 16 or 18 units causing severe growth depression, diarrhoea and deterioration in appearance when given to rats at the 20% level in a synthetic diet.…”

Biological observations from feeding heated corn oil and heated peanut oil to rats

“…The current generation is being socialized to enjoy the fast-food hamburger as well as many deep-fat fried foods such as fried chicken, fish pieces, french fries, and a variety of chips (Smith et al, 1985). Investigators studying fat derived from commercial deep-fat frying operations have demonstrated either substantial adverse reactions (Johnson et al, 1957;Poling et al, 1962;Sugai et al, 1962;Yoshida et al, 1975;Meltzer et al, 1981) or moderate nutritional effects (Keane et al, 1959;Nolen et al, 1967;Poling et al, 1970;Nolen, 1973) from feeding animals diets containing fats subjected to the heat and oxidation of normal usage. The commercially used fats normally were considered to be no longer fit for human consumption, or had reached the end of their frying life.…”

Effects of thermal oxidation on the constitution of butterfat, butterfat fractions and certain vegetable oils

“…There is sorne evidence in the early 1iterature that butterfat may have nutritional advantages over vegetable oils as... a cooking fat (Johnson et...al., 1956; Bhale ['ao et aL, 1959;Coombs et aL, 1965 A typical composItIon of the lipids in whole bovlne'mllk 1s given in Table 1. (Kurtz, 1974).…”