Mechanism of Spontaneous Heating of Hay Part 2 — Chemical Changes in Spontaneously Heated Hay

Chemical composition of Italian ryegrass samples spontaneously heated to 80 to 200° C was measured using acid detergent and enzymatic analysis methods. Chemical reactions in hay during spontaneous heating were studied. The amount of cellulose and hemicellulose decreased in spontaneously heated hay, but no changes were observed in sugar content. Protein was bound by spontaneously heating, resulting in the increase of artifact lignin and acid detergent fiber contents. The evaluation of heat and mass balances indicated that carbohydrate degradation products of cellulose and hemicellulose were lost in decomposition, oxidation, and Maillard reactions during the spontaneous heating.