Chemical composition and sensory quality of bovine milk as affected by type of forage and proportion of concentrate in the feed ration.
BACKGROUND
The objective of this study was to investigate how some small changes in the forage content of maize and lucerne silage and in the ration between forage and concentrate in the diet of dairy cows affect milk quality. Milk quality was assessed by quantitative descriptive sensory analysis and by analysis of tocopherols and carotenoids as well as fatty acid composition.


RESULTS
Changing the ratio between maize silage and lucerne silage from 5:1 to 2:1 increased milk fat content of carotenoids (23-27%) and C18:3 n3 (15%), and reduced stale aroma and creamy flavour. Increasing the proportion of concentrates in the feed ration from 0.2 to 0.4 increased energy corrected milk yield (26%), reduced fat content (-10%), increased C18 fatty acids (8-62%) and reduced C16 (-20%) content in milk fat. In addition, this milk type was described by the sensory panel as less oily, less saturated and less yellow. The changes in milk composition were related to differences in feed composition.


CONCLUSIONS
The study revealed the potential to produce milk with a distinct composition and sensory quality based on even small changes in the feed composition that are straightforward to implement by farmers.
Aarhus University, Department of Food Science, Blichers Allé 20, DK-8830 Tjele, Denmark.
Mette K
MK
Larsen
Ulla
U
Kidmose
Troels
T
Kristensen
Pierre
P
Beaumont
Grith
G
Mortensen
D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002338:Carotenoids / Q000378:metabolism; D004032:Diet; D004041:Dietary Fats / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D006801:Humans; D007774:Lactation / Q000378:metabolism; D000455:Medicago sativa; D008892:Milk / Q000378:metabolism*; D009753:Nutritive Value; D009812:Odorants; D012417:Rumen; D012820:Silage; D013649:Taste; D024505:Tocopherols / Q000378:metabolism; D003313:Zea mays
D004041:Dietary Fats; D005227:Fatty Acids; D002338:Carotenoids; D024505:Tocopherols