Growth of Lactobacillus paracasei ssp. paracasei on tofu whey

The liquid by-product of the soybean product tofu, tofu whey (TW), was used as a growth medium for the production of Lactobacillus paracasei ssp. paracasei LG3 cultures. The TW used in this study contained stachyose, raffinose, sucrose, fructose and glucose, but the strain used could only utilize the three latter. The lactobacilli population obtained in MRS broth was three times higher than that in TW alone, and supplementation of TW was thus examined. Of 19 mixtures of yeast extracts (YE), peptones and potato extracts examined, the best nitrogen sources were YE and tryptone. The addition of YE, salts (phosphates, citrates, Mg and Mn), glucose as well as Tween to TW tripled the populations to 2.9×109 cfu/ml, which was as high as that obtained in MRS broth. Growth of L. paracasei LG3 in cow rehydrated skim milk was inferior to that in TW.