Milk Components and Trace Components in Margarines (II)

Abstract

The content of iron and copper was determined in 53 brands of bakery and household margarines, 11 brands of butters and 24 brands of shortenings and lards. Investigations on the effect of these metals on the quality of products were also conducted.(1) Mean values (X) of iron content in various products are as follows: 1.53ppm for household margarine, 1.37 and 1.33ppm for salted and unsalted bakery margarine respectively, 1.55ppm for butter, 1.06ppm for shortening and 0.99ppm for lard.(2) The iron content was greater when iron was assumed to have been used in the manufacturing equipments. Margarine containing more than 2ppm of iron showed a rapid increase of peroxide value (POV) at 25°C. An oven test of shortening and lard indicated that the iron of 2-3ppm has no great effect on their quality.(3) The copper content was very small in any kind of the products examined and the mean values ranged from 0.26ppm to 0.46ppm. At this level, they seemed to have no effect on the quality of these products.(4) Examination of iron and copper content in 15 kinds of oils and fats used for manufacturing gave the mean values of 0.32ppm for iron and 0.31ppm for copper.Accordingly, the copper content is traced back to only the oils and fats used for manufacturing, and the iron content is considered to increase during manufacturing Processes.