Abstract
The flavor components of lucerne hay, Italian ryegrass and rice straw were isolated by trapping of headspace volatiles on Tenax-GC and by steam distillation and identified by a GC and a GC-MS to clarify the odors affecting the grass selection and intake of cattle. From these forage crops, a number of compounds, including 28 hydrocarbons, 20 alcohols, 2 esters, 7 aldehydes, 6 ketones, 1 lactone, 3 phenols, 12 acids, 5 sulfides and 5 halogen compounds, were obtained. The characteristic flavor components from three samples were as follows. 1) lucerne hay ; linalool, linalool oxide, geraniol, benzyl alcohol and methyl salicylate. 2) Italian ryegrass ; lauric, palmitic and stearic acids, hexanol, decanol, carbon disulfide, dimethyl sulfide and dimethyl disulfide. 3) rice straw ; the number of flavor compounds was smaller than the other two crops and all flavor compounds identified were also found in the lucerne hay and/or in the Italian ryegrass. It was indicated that the forage crop with high quality had a pleasant odor and was abundant in flavor components while the forage crop with poor quality was less odorous.
