Vitamin B12 production in Tempeh by non-sequential mixed fermentation at laboratory and bench scales / by Warawut Krusong.

Thesis (Ph.D.--Food Science) University of the Philippines

Includes bibliographical references.

College of Agriculture, Food, Environment and Natural Resources (CAFENR)

WARAWUT KRUSONG, University of the Philippines at Los Banos. December, 1990. Vitamin B12 Production in Tempeh by Non-Sequential, Mixed Fermentation at Laboratory and Bench Scales Major Professor: Dr. Priscilla C. Sanchez
Soybeans of the Phraputthabath variety were soaked in acidified distilled water (1% of 80% lactic acid) for 2 hr at 70° C, dehulled by and dried at 80aC until the beans were superficially dry. The cotyledons were sterilized and inoculated with Rhizopus oliqosporus powdered inoculum at a rate of-0.25 g per 50 g soybean and cell suspension of Propionibacterium shermanii 1250 at 1 ml per 50 g, The mixture was incubated at 35 C for 24 hr.
Lactobacillus casei did not affect he vitamin /312 production of ii 1250 in tempeh when added during the soaking of the beans when added with P. shermanii 1250 during fermentation. optimum conditions obtained for vitamin 131.2 production by P. i 1250 in tempeh at laboratory scale consisted of 55% moisture of the beans (50 g in Petri dish), mixed culture of 5.0% P. 1250 and 0.5% R. oliqosporus inoculum and incubation of 35°C for 24-48 hr. The highest yield of vitamin 1312 at optimum conditions was 308.4 ng per 100 g.
In general, compounds such as protein, fat, ash, and amino nitrogen increased during fermentation while carbohydrate (by difference), soluble carbohydrate and fiber decreased as fermentation progressed. In addition, the concentration of most of the amino ds, especially lysine and methionine, were higher in high vitamin tempeh as compared with those in the unfermented soybean. Optimum conditions used in bench scale were similar to that used laboratory scale. Bench scale production of high vitamin B12- performed in stainless steel trays (30 cm x 45 cm x 3 cm), yielded of 297.47 ng vitamin )312 per 100 g of mixture at optimum Lions of 2 cm thickness of sterilized soybean mass (1,400 g per ) covered with non-perforated aluminum foil, and incubation period hr at 35°C The chemical composition of high vitamin B10-tempeh in trays at optimum conditions was also similar to that in laboratory scale mass balance in the production of high vitamin B12-tempeh in at optimum conditions showed that 30.14% of total solids was ring processing. Intermediate metabolites involved in the pathway of vitamin P. shermanii 1250 in tempeh (as detected by gas chromatography) acetic acid which increased and propionic acid which decreased as fermentation time progressed. Moreover, succinic acid and glycine decreased during fermentation.
This research was the first to elucidate that mixed fermentation with R. oliciosoorus and P. shermanii 1250 enhanced the high vitamin B12 production in tempeh. Non-sequential mixed fermentation which differed from the ordinary mixed fermentation was demonstrated.
Several advantages in tempeh fermentation were found, namely: 1) besides the production of vitamin B12 in tempeh, the reduction of sporulation of Rhizopus that affected the texture and appearance of tempeh was attained, 2) the ammonia smell which is normally found in high amount in traditional tempeh and make the product unacceptable, especially to westerners, was also reduced during- fermentation, 3) since Propionibacterium is normally used as starter in cheese-making, it provides the favorable-flavor acceptable to non-Asian. The product is acceptable to both orientals and westerners due to the effect of this mixed fermentation process.

Submitted to the University Library 07/18/2007 T-1510