Application of propidium monoazide coupled with quantitative PCR to evaluate cell viability of Bifidobacterium animalis subsp. lactis in a non-dairy probiotic beverage

Table 4 Comparison of B. animalis subsp. lactis BB-12 count (log CFU/g) obtained by qPCR, PMA-qPCR, and plate count of the three formulations of microencapsulated probiotic passion fruit juice samples collected at 1 and 30 days of storage

Sample	qPCR count (log CFU/g)^a		PMA-qPCR count (log CFU/g)^a		Plate count (log CFU/g)^b
Sample	Day 1	Day 30	Day 1	Day 30	Day 1	Day 30
M1^*	10.49 ± 0.17	10.43 ± 0.17	7.95 ± 0.08	8.78 ± 0.30	8.74 ± 0.08	8.78 ± 0.04
M2^*	10.76 ± 0.12	10.22 ± 0.20	8.69 ± 0.09	8.89 ± 0.14	8.69 ± 0.05	8.64 ± 0.05
M3^*	10.36 ± 0.28	9.95 ± 0.24	8.92 ± 0.51	8.50 ± 0.35	8.51 ± 0.04	8.49 ± 0.03

^aValues are mean ± SD (n = 12), qPCR duplicate of two independent DNA extracts in three independent runs
^bValues are mean ± SD (n = 4), quadruplicate plate count
^*Encapsulating agents (% m/v): M1 20% maltodextrin, M2 10% maltodextrin 10% inulin, M3 20% inulin