Chemical, Microbiological, and Functional Characterization of Kefir Produced from Cow’s Milk and Soy Milk

Table 6

Viable counts for fermented kefir made from cow’s milk and soy milk.

Kefir	Fermentation time (d)^1	Medium	Viable counts of respective colony morphology groups (CFU mL^−1)	Species of representative strains identified dependent on 16S/26S rDNA^2
Fermented milk	1	GYC	3.11 ± 0.14 × 10^6	Acetobacter orientalis
		MRS	6.20 ± 0.02 × 10^7	Lactococcus lactis
		MRS	—^3	Lactobacillus gallinarum
		GAM	5.10 ± 0.12 × 10^7	Lactococcus lactis
		GAM	—	Lactobacillus gallinarum
		PDA	2.86 ± 0.48 × 10^6	Kazachstania unispora
		PDA	2.04 ± 0.03 × 10^6	Pichia kudriavzevii
		PDA	2.50 ± 0.70 × 10^4	Galactomyces candidum
		PDA	—	Geotrichum bryndzae
	4	GYC	6.50 ± 3.53 × 10^7	Acetobacter orientalis
		MRS	9.35 ± 0.21 × 10^8	Lactococcus lactis
		MRS	—	Lactobacillus kefiri
		GAM	8.90 ± 0.71 × 10^8	Lactococcus lactis
		PDA	1.90 ± 0.53 × 10^7	Saccharomyces cerevisiae
		PDA	1.91 ± 0.04 × 10^6	Kazachstania unispora
		PDA	4.50 ± 3.53 × 10^4	Pichia kudriavzevii
	7	GYC	4.50 ± 2.12 × 10^7	Acetobacter orientalis
		MRS	1.37 ± 0.07 × 10^9	Lactococcus lactis
		GAM	1.55 ± 0.17 × 10^9	Lactococcus lactis
		PDA	1.90 ± 0.99 × 10^7	Saccharomyces cerevisiae
		PDA	1.89 ± 0.04 × 10^6	Kazachstania unispora
		PDA	2.00 ± 1.41 × 10^4	Pichia kudriavzevii
Fermented soy milk	1	GYC	NC^4
		MRS	2.47 ± 0.10 × 10^9	Lactococcus lactis
		GAM	2.42 ± 0.02 × 10^9	Lactococcus lactis
		PDA	1.05 ± 0.32 × 10^4	Kazachstania unispora
	4	GYC	NC
		MRS	3.15 ± 0.78 × 10^9	Lactococcus lactis
		GAM	4.40 ± 1.27 × 10^9	Lactococcus lactis
		PDA	1.48 ± 0.10 × 10^4	Kazachstania unispora
		PDA	2.60 ± 1.98 × 10^4	Saccharomyces cerevisiae
	7	GYC	NC
		MRS	3.25 ± 1.34 × 10^9	Lactococcus lactis
		MRS	—	Lactobacillus nagelii
		GAM	3.55 ± 0.35 × 10^9	Lactococcus lactis
		GAM	—	Lactobacillus nagelii
		GAM	—	Lactobacillus plantarum/pentosus
		PDA	2.01 ± 0.04 × 10^4	Kazachstania unispora
		PDA	3.35 ± 1.91 × 10^3	Saccharomyces cerevisiae

¹Seven days of sequential fermentation (each step was conducted at 25°C for 24 h, in total seven times) of cow’s milk and soy milk. ² Microorganisms that were isolated and identified but viable counts of them were under the detection limit (<3 × 10³ CFU mL⁻¹). ³NC: not counted nor isolated (˂10³ CFU mL⁻¹).