鳕鱼下脚料水解液的连续乳酸发酵

Continuous Lactic Acid Fermentation of Haddock Hydrolysate

探讨了胚芽乳杆菌在鳕鱼下脚料水解液(4 g／L葡萄糖)中的生长及产酸情况,结果表明,在32℃的恒温室,经过24 h的静止培养,水解液的pH值为4.3,菌落数(CFU)为4.0×109,低于相同条件下在MRS培养的pH值3.8,菌落数(CFU)5.5×109;但在水解液中培养至72 h时,水解液的pH值可降至4.1.在水解液中静止培养的前20 h是胚芽乳杆菌生长的旺盛期,连续培养应从静止培养15 h、pH值4.5左右开始.在连续培养的105 h内,新鲜培养基的流加速度为70 mL／d,pH值几乎能恒定在4.5左右,葡萄糖和乳酸含量也基本保持恒定.

In this paper, Lactobacillus plantarum was incubated in haddock hydrolysate with 4. 0 g/L glucose at 32 ℃. After 24 hours' incubation, the pH value and the colony forming units (CFU) were 4. 3 and 4. 0×109 respectively, while those values in fermentation with MRS medium 3. 8 and 5, 5×109, respectively. The pH value of haddock hydrolysate could reach to 4. 1 after 72 hours' batch incubation, and the fast growth period was the first 20 hours. The continuous fermentation was started after 15 hours' batch incubation and the pH value dropped to 4. 5. Continuous lactic acid fermentation was successfully conducted for a period of 105 hours at a nutrient feed rate of 70 mL/d, and a constant pH of 4. 5, lactic acid and glucose concentration were maintained constantly.