The effect of storage temperature and antioxidant treatment on the chemical and nutritive characteristics of herring meal

Abstract

The effects of storage temperature and antioxidant treatment on the chemical and nutritive properties of herring meal were studied. The following observations were made: Low‐temperature (−20°C.) storage promoted more rapid decrease in ether extractability and in iodine value of the ether extract than did storage at 25.5°C. Antioxidant treatment prevented the decrease both in ether extractability and iodine value of the extract. Binding of the lipid into a complex from which the lipid was extractable with acetone only after HC1 treatment occurred early in the storage period. After six weeks the amount of lipid in this fraction decreased, presumably as a result of further oxidation and polymerization into more refractory compounds. Pepsin digestibility tests showed that BHT‐treated meal contained the lowest amounts of undigestible nitrogen. Meals subjected to −20°C. contained the most undigestible nitrogen. All meals were similar in nutritive value as protein or vitamin‐B supplements in chick diets, composed of natural ingredients, even after storage for nine months. As the sole source of protein in a purified diet, the meal kept at −20°C. from time of processing promoted slower growth than the other meals.

Nutritional and Chemical Changes in the Lipid Fraction of Herring Meals with and without Antioxidant Treatment

“…It was reported previously (March et al, 1960) that BHT-treatment of herring meals retarded the decrease in both ether-extractability and iodine value of the extract. This stabilizing effect of BHT was also apparent in the present test.…”

Reactions in food systems: negative temperature coefficients and other abnormal temperature effects

“…In a rather different context, Banks (1950) and other workers (Lea, Parr and Carpenter, 1958;March et al, 1961) showed that autoxidation of the fats in dehydrated herrings and herring meal proceeds faster at lower temperatures than at higher temperatures. Thus Lea et al (1958) found the rate faster at 10°C than at 37"C, Banks (1950) found it faster at 0°C than at 25°C and March et aZ.…”