THE EFFECT OF LIGHT ON THE VITAMIN-B2 AND THE VITAMIN-A CONTENT OF CHEESE

Edam type cheese was exposed to sunlight at ambient temperature and to fluorescent light at 5-degrees-C. The loss of vitamin B2 (riboflavin) and vitamin A was monitored in both the surface and inner layers of t he cheese and the results compared with control samples kept in the da rk. The loss of riboflavin when exposed to sunlight was shown to be pr imarily a surface effect but losses of vitamin A were similar througho ut the cheese. When exposed to fluorescent light at 5-degrees-C and mo nitored at intervals for 10 days the loss of riboflavin was still grea test at the surface but a trend to lower values than the control was e vident throughout the cheese. Vitamin A losses followed a different pa ttern in both sunlight and fluorescent light. There was a heavy initia l loss throughout the cheese. Under fluorescent light this was followe d by a period in which further loss was mainly in the surface layer. V acuum packaging reduced the loss of riboflavin but had no effect on th e loss of vitamin A.