The optimum conditions for preparation of microcapsules containing of living cells of L. delbrueckii TISTR 108 by the interfacial polymerization method were with 2% by weight of 1,6-hexanediamine and 5% by volume of sebacoylchloride as hydrophilic and hydrophobic monomers, respectively, a mixed solvent with volume ratio of 5:1 of cyclohexane-chloroform mixture containing Span 85 as an emulsifier, and 4.5-10.0 x10 (superscript 8) cells/ml of cell suspension, react at pH 7.0 for 3 min with stirring in the presence of case in. Under such conditions the prepared microencapsulated cells (MC) of lactic acid bacteria could produced 0.98 mg of lactic acid/ml of GYP medium while the free cells could produced 2.85 mg/ml of lactic acid. Furthermore, the MC of Z. rouxii NRRL Y-2547 prepared from 7% by weight of 1,6-hexanediamine, 6% by volume of sebacoylchloride and a mixed solvent with volume ratio of 5:1 of cyclohexane-chloroform mixture and 2.0-5.2 x 10 (superscript 7) cells/ml, were found to produce 0.68% by volume of alcohol in the YM medium which was more than that of free cells (0.58% by volume of alcohol). The SEM micrograph of the white MC of bacteria and yeasts of 4 microns in diameter clearly shows that whole cells are well encapsulated. The reason for this was examined, and it was found that the both the both MC obtained were stable and no leakage of both cells into surrounding medium when incubation for 1 month. It was also found that the whole cells in the both microcapsules were more resistant to 20% by weight of sodium chloride than free cells under lactic acid and alcohol fermentative condition. Production of lactic acid and alcohol from soy protein hydrolysate (SPH) with addition of 1% by weight of glucose by MC was carried out in both a batch system and continuous system under fluidized MC reactions. Under the batch system, the MC of L. delbruekii was found to produce 0.78 mg/ml of lactic acid after statically incubation in the SPH for 14 days at 40ºC. Introduction of the MC of Z. rouxii into the above lactic fermented SPH caused 0.54% by volume of alcohol to be produce within 14 days at 25ºC. The development of lactic acid and alcohol fermentation of SPH was found via 3-connected reactors containing MC of bacteria and yeasts. The three reactors (2.0 x 35 cm) were operated in fluidized-bed manner. Lactic acid and ethanol productivities as high as 1.98 mg/ml and 0.62% (v/v), respectively, were achieved within 72 hrs in SPH. Organoleptic on the lactic acid and alcohol fermented SPH, so called soy sauce produced using the proposed method showed good rating for aroma, taste and total acceptance.
