5 YEARS STUDIES ON THE CONVERSION TO ECOL OGICAL MILK-PRODUCTION .2. MILK QUALITY AND ANIMAL HEALTH

In a trial with 2 x 30 cows on the experimental farm Schaedtbek once a month during the fourth and fifth year of the trial milk from ecologi cal and conventional production was tasted and evaluated. Furthermore on 12 terms Edamer cheese was produced and evaluated after five and te n weeks storage. In weekly samples the renneting properties were deter mined, and the consistency of milk fat was measured by penetrometry. I n addition the composition of milk fat was determined by gas-chromatog raphy on 16 terms. By triangel test significant flavor differences wer e observed on 8 test days (out of 32).However, they disappeared in pas teurized milk with equal fat content. There were no differences either in the cheese trial regarding appearance, smell, taste and texture of cheese samples. Renneting was slower in ecologically than in conventi onally produced milk, especially during the winter feeding period of c ows. The milk fat of ecologically produced milk was marked by higher c ontents of unsaturated fatty acids, the penetration values indicated a better spreadability of butter. The content of contaminants was very low in both groups, and there were no significant differences between sources. With regard to udder health there was no indication for a sup eriority of ecological management, for fertility traits, however, the picture was slightly in favour of the ecologically kept cows.