Table 6.

Acidification properties (pH and TTA) of sourdough obtained with EPS⁺ and EPS⁻ starter cultures after 15 and 30 h of incubation at 30°C^a

Exptl condition	Result with EPS+ starter at:		Result with EPS− starter at:
	15 h	30 h	15 h	30 h
Control
pH	4.03 ± 0.15	3.99 ± 0.09	4.09 ± 0.13	4.02 ± 0.12
TTA	2.65 ± 0.49	4.54 ± 0.13	2.70 ± 0.28	4.38 ± 0.18
5% S
pH	4.08 ± 0.24	4.07 ± 0.07	4.16 ± 0.28	4.18 ± 0.18
TTA	6.40 ± 0.98	8.65 ± 0.49	5.30 ± 0.28	7.50 ± 0.70
5% S + 0.5% YE
pH	4.05 ± 0.03	3.99 ± 0.06	4.15 ± 0.10	4.18 ± 0.03
TTA	6.78 ± 0.50	9.50 ± 0.70	5.73 ± 0.45	7.50 ± 0.03
10% S
pH	4.15 ± 0.06	4.02 ± 0.01	4.18 ± 0.04	4.04 ± 0.01
TTA	6.45 ± 0.07	7.70 ± 0.25	5.15 ± 0.20	6.15 ± 0.49
10% S + 0.5% YE
pH	4.19 ± 0.049	4.02 ± 0.06	4.19 ± 0.01	4.07 ± 0.02
TTA	6.70 ± 0.28	7.75 ± 0.35	5.5 ± 0.42	7.00 ± 0.70
5% S + EPSb
pH	4.17 ± 0.06	4.04 ± 0.16	ND	ND
TTA	8.05 ± 0.21	8.85 ± 0.07	ND	ND

^aEPS⁺ starter cultures were composed of Leuconostoc lactis 95A and Lactobacillus curvatus 69B2, and EPS⁻ starter cultures were composed of Leuconostoc lactis 68A and Lactobacillus curvatus 68A2. Data are means from duplicate analysis of replicate experiments. ND, not determined; S, sucrose; YE, yeast extract. pH and TTA values detected in all experimental conditions immediately after dough mixing were in the range of 3.99 to 4.09 and 0.60 to 0.65 ml NaOH 0.1N/10 g, respectively. The sourdoughs were prepared with 5 or 10% sucrose with and without 0.5% yeast extract.

^bSourdough prepared with the addition of EPS (20 ml/500 g of flour) collected directly from the ropiness plates as described in the text.