Effect of microwave heating on the thiamin content of cows' milk

Vitamin losses: Retention during heat treatment and continual changes expressed by mathematical models

“…However, at temperatures of 110 and 120 1C, while vitamin B 1 content of milk remained constant, pyridoxamine content increased (4-5% and 9-11%, respectively) and pyridoxal content decreased (5-6% and 9-12%, respectively). Also, Vidal-Valverde and Redondo (1993) mentioned that vitamin B 6 losses did not depend on the fat content of milk.…”

Influence of heating conditions in continuous-flow microwave or tubular heat exchange systems on the vitamin B1 and B2 content of milk

“…The objective of the present work was to study the effect of continuous-flow microwave heating of milk at high temperature on vitamin B 1 and vitamin B 2 , and to compare it with a conventional heating process under similar conditions and with the batch microwave heating [11,23].…”

Riboflavin, α-tocopherol and retinol retention in milk after microwave heating

“…Fellman et al (1991) showed that vitamin A was more stable in low fat milk than in skim milk after exposure to Iight. Vidal- Valverde and Redondo (1993) also found that the degradation of thiamin after microwave heating of milk is inversely proportional to the level of fat. The fact that extended heating (up to 4 min) did not further modify the a-tocopherol content of low fat milk could perhaps indicate that a certain portion of the native a-tocopherol is lost rapidly on microwave treatment, with the remaining portion being resistant to further destruction.…”

“…However, bibliographic data about the effect of microwave heating on the vitamin content of milk are very scarce. Vidal-Valverde and Redondo (1993) found that microwave heating of milk partly destroys its thiamin and this effect is directly proportional to temperature and time and inversel y proportion al to the lever of fat. In this study we observed that after microwave heating the retention of riboflavin ranged between 97-100% and no influence was observed for the lever of fat of milk.…”

“…It is assumed than the nutritive value of food is scarcely affected after microwave heating. Few data exist on the effects of microwave heating on the vitamin content of milk (Cross and Fung, 1982;Vidal-Valverde and Redondo, 1993). It is known that tocopherols are sensitive to oxidation, heat and light.…”