Development Of A Liophylized Bacterial Preparation For Silaging With The Optimum Proportion Of Lactic Avid And Propionic Acid Bacteria
M. A. Kartashov, T. M. Voinova, A. V. Sergeeva, N. V. Statsyuk, S. V. Rogovsky, Ya. O. Grebeneva, D. A. Durnikin
Silage represents the main forage for agricultural animals during a winter period and requires the use of preservatives providing the maintenance of its quality. The use of microbial biopreservatives improves the silage consumption and productivity of animals. Multicomponent biopreservatives containing lactic acid and propionic acid bacteria are able to significantly improve organoleptic qualities and preservation of silage, especially its aerobic staility. In this study, the technology of production of liophylized bacterial preparations of earlier developed Lactobacillus plantarum VKPM B-4173, Lactococcus lactis subsp. lactis VKPM В-2092, and Propionibacterium acidipropionici VKPM В-5723 strains, characterized by valuable traits, has been developed. The optimum modes of the culture broth concentration and freeze-drying have been developed, which provide the minimization of biomass losses and obtaining of dry preparations containing at least 1 · 1011 CFU/mL of viable cells. The optimum flow rate for the streaming centrifuging was 130 L/h, and the optimum temperature and duration of a preliminary freezing before the freexe-drying were 8 h at –35-40°С or 12-14 h at –25°С. The analysis of the effect of different proportions of the used strains in the final preparation on some qualitative characteristics of silage made it possible to determine the optimal proportion of L. plantarum VKPM B-4173, L. lactis VKPM В-2092, and P. acidipropionici VKPM В-5723 strains equal to 2 : 2 : 1, respectively. The use of such biopreservative provides the maintenance of the maximum protein content (94% of the initial level) and the maximum concent of total organic acids (2.9%) in the corn silage at the 60th day of storage. In this case, the content of lactic and acetic acids was equal to 69.4 and 31.1% of the total organic acid content, respectively. In addition, this proportion provided the minimum ammonium content in the silage (125±5 ppm or 61.6% of the control). Based on the obtained results, authors recommend to use the developed biopreservative for the improvement of the silage quality.