A study of the microorganisms from grass silage. II. The lactobacilli.

Few workers have attempted to perform a systematic study of the lactic acid bacteria in silage. As a result, the sequence changes, comparative growth rates, and the effect individual species have upon the fermentation process remain relatively obscure. Many investigators have reported that lactic acid in silage is produced mainly by Lactobacillus plantarum. The importance of the high acid producing lactobacilli in the fermentation process cannot be overlooked, in spite of the fact that few of these organisms are found on the fresh plant material. It should be noted, however, they usually do not become predominant until after the cocci have reached high numbers and produced considerable amounts of acids (Langston et al., 1958; Langston and Bouma, 1960). This sequence change from lower acid producing cocci to higher acid producing lactobacilli is recognized in many types of fermentations. The object of this work was to gain a better understanding of the types of lactobacilli that proliferate in silages and their contribution at different stages of the fermentation process.