Background: Raw milk, meat and plant materials are subjected to high risks of contamination by various pathogenic bacteria and thus their growth prevention is a great challenge in the food industry. Food fermentation by lactic acid bacteria (LAB) besides changing its organoleptic characteristics also helps to eliminate unfavorable microflora and represses growth of pathogens. To the date only few LABs has been reported to exhibit activity against bacteria embedded in the biofilms characterized by extreme resistance to antimicrobials, high exchange rate with resistance genes and represent high risk factor for foodborne disease development. Results: Six novel LAB strains isolated from the clover silage exhibited pronounced antibacterial activity against biofilm embedded pathogens. We show explicitly that these strains demonstrate high acidification rate, completely repress the growth of E. coli, S. aureus and to a lesser extent P. aeruginosa as well as exhibit appropriate probiotic and milk-fermenting properties. Moreover, in contrast to the approved probiotic strain Lactobacillus plantarum 8PA3, the new isolates were able to efficiently eradicate preformed biofilms of these pathogens and prevent bacterial spreading originating from the biofilm. We suggest these strains as potential additives to the pre-cultures of conventional LAB strains as efficient tools targeting foodborne pathogens in order to prevent food contamination from either seeded raw material or biofilm-fouled equipment. Conclusions: The AG10 strain identified as L. plantarum demonstrate attractive probiotic and milk fermentation properties as well as high resistance to simulated gastric conditions thus appearing perspective as a starter culture for the prevention of bacterial contamination originating from fouled equipment during milk fermentation.

Two multienzyme bacterial preparations of α-amylase of Bacillus licheniformis and Amylosubtilin ® were used in order to modify potato starch at various enzyme concentrations. Eight types of starch were obtained, and their morphological, functional, and physical and chemical characteristics were studied. Induction of enzyme preparations allowed obtaining starches characterized by extended solubility and water-sorption ability and also lower gelation temperatures and viscosity. It was found that studied amylolytic preparations do have different effects on starch granules, despite the identical major amylase activities. e combination of the characteristics studied in the enzymatically modified starches makes them promising for the use as a component of food systems requiring the corrections of their textural features.

The demand for dairy products globally is increasing. No exception for yogurt. As a quick and healthy drink, yogurt's consumers demand lower fat content for health reasons. yogurt loss its original texture and viscosity if the fat content is lower than normal. To resolve the issue, fat replacers are added to the low-fat yogurt. In this study we used enzymatically modified potato starch as the fat replacer. The results showed that the characteristic of low-fat yogurt with the addition of modified starch with amylosubtilin and amylase from Bacillus licheniformis are quite similar to native starch.

Milk fermentation by lactic acid bacteria both enhances its nutritional value and provides probiotic strains to correct the intestinal microflora. Here, we show the comparative analysis of milk fermented with the new strain, Lactiplantibacillus plantarum AG10, isolated from silage and the industrial strain Lactobacillus delbrukii subs. bulgaricus. While the milk acidification during fermentation with L. plantarum AG10 was lower compared with L. bulgaricus, milk fermented with L. plantarum AG10 after a 14-day storage period retained a high level of viable cells and was characterized by an increased content of exopolysaccharides and higher viscosity. The increased EPS production led to clot formation with higher density on microphotographs and increased firmness and cohesiveness of the product compared with L. bulgaricus-fermented milk. Furthermore, the L. plantarum AG10-fermented milk exhibited increased radical-scavenging activity assuming lower fat oxidation during storage. Taken together, these data suggest that L. plantarum AG10 seems to be a promising starter culture for dairy products with lowered levels of lactic acid, which is important for people with increased gastric acid formation.