Characteristics of New Sourdough using Lactic Acid Bacteria and Wild Yeast

We examined the various effects of lactic acid bacteria (LAB) and yeast on sourdough bread and aimed at the development of a new sourdough bread using wild yeast isolated from fruit and LAB isolated from a traditional Japanese fermented fish (funa-sushi). We made sourdough by using Lactobacillus paracasei NFRI 7415 and baker’s yeast isolated from fruit. Fermentation tests of four types of sourdough were carried out for 4 days: LAB+yeast (28°C), LAB (28°C), LAB and yeast (8°C) and LAB (8°C). The CO2 production and the organic acid and free amino acid contents of the sourdough from LAB and yeast fermented at 28°C were higher than those of the other sourdough. These results indicate that for the new sourdough, the most suitable fermentation period is 3 days and the most suitable temperature is 28°C. Our findings demonstrate that it is possible to develop new sourdough bread using sourdough by the co-fermentation of LAB and wild yeast.