Fatty Acid Composition of Hay

Abstract

Fatty acid composition of hay was studied by gas liquid chromatography. Timothy-grass, red clover, and tufted-hair grass were compared. The influence on fatty acid composition of timothy-grass of growth stage, harvesting methods, climatic factors, and artificial drying was studied. In new-mown hay from the various species, a closely similar fatty acid pattern was observed. Approximately 50% of the total fatty acid content was linolenic acid. In timothy-grass cut at a late stage of growth a low linolenic acid content was demonstrated (21.8%). Hay dried on poles largely maintained its original fatty acid composition for the entire experimental period. In cocked hay no changes occurred during fair weather. Coinciding with a period of rainfall a considerable decrease occurred in linolenic acid content (to 18.5%). Watering of cocked hay resulted in a successive change of the fat. Hay dried as a swath showed marked, successive changes of fatty acid composition even under favorable weather conditions. The decrease in linolenic acid content (to 11.7%) was more conspicuous if the hay was watered. In new-mown hay, artificially dried in an electric oven, the linolenic acid content was higher than in a corresponding sun-dried sample. © 1966, American Dairy Science Association. All rights reserved.