The effect of sapropel extracts on microflora and physicochemical parameters of Dried Distillers’ Grain
¹Saint Petersburg National Research University of Information Technology, Mechanics, and Optics, Department of Food Biotechnology (Vegetable stock), Lomonosova street 9, RU191002 St. Petersburg, Russia
²Federal State-funded Scientific Establishment, ‘Russian Academy of Sciences (RAS) Limnology Institute’ (INOZ RAN), Syevasťyanova street 9, RU196105 St. Petersburg, Russia
This article is devoted to the effect of ultradispersed humate sapropel extracts, obtained from air-dry samples of sapropel, from Seryodka deposit (Pskov region, Russia) by alkaline extraction under the action of ultrasonic radiation, on microbial and physicochemical parameters of Distillers’ grain (DG) during storage. At the end of the distillation, wet DG was divided and treated with sapropel extract. The untreated sample served as a control. Both (treated and untreated) were then dried to 10% moisture content. Microbial and physicochemical parameters (moisture content, pH, titrable acidity (TA), acid value (AV) of fats) were assessed before storage of dried DG. A similar experiment was repeated after one week of storage but on microbial load. The microbial counts ranged from 2.3 × 104 CFU g-1 (untreated) to 1.77 × 104 CFU g-1 (treated) before storage while 2.5 × 104 CFU g-1to 2.18 × 104 CFU g-1 accounted for after a week of storage. The pH had increased from 4.5 ± 0.1 to 6.1 ± 0.1 before and after treatment respectively. TA likewise decreased from 3.2 ± 0.4 to 2.03 ± 0.06%. The results showed that sapropel extracts had effects on microflora and physicochemical parameters of DDG.