The effects of continuous flow microwave treatment and conventional heating on the nutritional value of milk as shown by influence on vitamin B-1 retention

The effects of continuous now microwave treatment and conventional heating (using a plate heat exchanger) on the nutritional value of raw mill; was es timated by measurement of the Vitamin B-1 retention. Microwave heating, wit hout a holding phase, did not modify the vitamin B-1 content of milk, where as analogous treatment carried out with the plate heat exchanger led to a l oss of this vitamin. A holding phase caused a similar loss of vitamin B-1 i n milk heated using either system. These results indicate that continuous f low microwave treatment of milk compares favourably with conventional heati ng because it produce less destruction of vitamin B-1 in milk. This could b e attributed to the shorter time taken to reach the final temperature and t he lack of hot surfaces in contact with the milk in the case of the microwa ve system.