Factors Affecting the Susceptibility of Multivitamin Mineral Milk to Oxidation

• Published in: Journal of dairy science 1962-12, Vol.45 (12), p.1449-1455
• Main Authors: Scanlan, R.A., Shipe, W.F.
• Format: Article
• Language: English
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(62)89654-4

The flavor of multivitamin mineral (MVM) milk was not affected when it was processed in a conventional HTST pasteurizer-homogenizer system. However, when it was subjected to a steam-vacuum treatment, in addition to pasteurization and homogenization, an oxidized flavor developed. The off-flavor developed regardless of whether the MVM preparation was added before or after processing. This indicates that alteration of the milk, rather than the MVM preparation, was involved in the development of the oxidized flavor. It was observed that homogenized-treated milk from another milk plant did not develop an oxidized flavor when fortified with MVM mix. Results indicated that the difference in susceptibility between the homogenized-treated milk from the two plants was due to processing differences. The iron compound, ferric pyrophosphate soluble, was identified as the ingredient in the MVM preparation causing the oxidized flavor. Fortification of homogenized and homogenized-treated milks with ferric and ferrous compounds showed that both milks developed oxidized flavors when fortified with ferrous iron. However, the homogenized-treated milk was more susceptible than the homogenized milk when ferric iron was added. It was suggested that the difference in susceptibility between homogenized and homogenized-treated milk is a difference in the capacity of these milks to reduce ferric iron to the stronger pro-oxidant ferrous form. Measurements of the relative amounts of iron reduced by these milks substantiate this explanation.