Reduction of Bacillus Cereus Growth in Oat Tempeh with Co- Fermentation of Different Lactic Acid Bacteria and Rhizopus oligosporus

Tempeh is a traditional soy product originally from Asia. Because of its nutritional value, tempeh is used worldwide in vegetarian cuisine, where it is used as a meat analogue Oat tempeh is produced with Rhizopus oligosporus PTCC 5287 with approximately 104 CFU/g. Biological acidification is carried out with inoculation of three starters containing streptococcus,Lactobacillus, lactococcus and chemical acidification is provided by the addition of 5ml/100g vinegar. Bacillus cereus is inoculated with approximately 105 CFU/g. The Results showed that co- fermentation of lactic acid bacteria and Rhizopus oligosporus caused a decrease in mold growth (p<1%). The highest effect is from the tempeh that was produced with lactococcus lactis sub sp lactis, lactococcus lactis subsp cremoris and the one that was acidified with vinegar. The highest ergostrol and hyphal length is related to the non- acidified tempeh. Biological and chemical acidification caused decreases in Bacillus cereus growth. The highest decrease was observed in tempeh that was made with lactococcus lactis sub sp lactis, lactococcus lactis subsp cremoris. In all the cases tempeh with good quality was produced.