Examination of the technological properties of newly isolated strains of the genus Lactobacillus and possibilities for their application in the composition of starters

Figures & data

Table 1. Total titratable acidity and concentration of viable cells of the four 24-h suspensions of the four Lactobacillus strains.

Strain	TTA (°T)	N (cfu/cm^3)
L. brevis LBRZ7	157.08	5.2 × 10^12
L. casei ssp. rhamnosus LBRC11	75.48	8.0 × 10^10
L. fermentum LBRH9	118.93	1.3 × 10^13
L. plantarum LBRZ12	116.69	2.4 × 10^12

Table 2. Changes in the total titratable acidity (TTA (°N)) of single-strain sourdough at repeated daily kneading for 96 h.

Time (h)	0	24	48	72	96
Single-strain sourdough
L. brevis LBRZ7	1.7	5.7	11.2	11.1	10.4
L. casei ssp. rhamnosus LBRC11	1.4	8.1	10.9	10.4	10.1
L. fermentum LBRH9	1.8	5.3	9.8	10.6	10.2
L. plantarum LBRZ12	1.7	10.7	10.4	10.1	10.2

Figure 1. Concentration of viable cells of lactobacilli of sourdough at repeated daily kneading for 96 h.

Table 3. Changes in the total titratable acidity (TTA (°N)) in wheat sourdough with starter cultures that are kneaded repeatedly every 24 h over a period of 96 h.

Time (h)	0	24	48	72	96
Wheat sourdough
Four-strain starter	2.5	9.0	8.4	12.7	17.3
Two-strain starter	2.9	8.8	10.4	15.0	16.4

Figure 2. Concentration of viable cells of lactobacilli, molds and yeasts in the four-strain starter sourdough during repeated kneading every 24 h over a period of 96 h.

Figure 3. Change in the concentration of viable cells of lactobacilli, molds and yeasts in the two-strain starter sourdough during repeated kneading every 24 h over a period of 96 h.

Table 4. Antimicrobial activity of the two 96-h sourdoughs against Bacillus subtilis, Aspergillus niger, Saccharomyces cerevisiae, Penicillium sp. and Rhizopus sp. d (mm) well = 6 mm.

Sourdough with starter	Four-strain starter	Two-strain starter
Saprophyte
Bacillus subtilis 3.5 × 10^5 cfu/cm^3	15.2	15.0
Aspergillus niger 6.4 × 10^4 cfu/cm^3	10.5	10.0
Saccharomyces cerevisiae 8 × 10^4 cfu/cm^3	–	–
Penicillium sp. 8 × 10^4 cfu/cm^3	15.3	15.0
Rhizopus sp. 3.2 × 10^4 cfu/cm^3	10.5	10.0

Figure 4. Evaluation of the variants of bread with sourdough with the two-strain starter.

Figure 5. Evaluation of the variants of bread with sourdough with the four-strain starter.

Table 5. Bacterial bread spoilage by Bacillus sp. during incubation of baked breads for 24–72 h at room temperature (RT) or 37 °C.

		24 h		48 h		72 h
Bread	T (°C)	Degree of spoilage	Odour	Degree of spoilage	Odour	Degree of spoilage	Odour
Control (without sourdough)	RT	–	No	–	No	I	Yes
	37	–	No	I	Yes	II	Yes
Two-strain starter sourdough 10%	RT	–	No	–	No	I	Yes
	37	–	No	–	No	I	Yes
Two-strain starter sourdough 15%	RT	–	No	–	No	I	Yes
	37	–	No	–	No	I	Yes
Four-strain starter sourdough 10%	RT	–	No	–	No	–	No
	37	–	No	–	No	I	Yes
Four-strain starter sourdough 15%	RT	–	No	–	No	–	No
	37	–	No	–	No	–	No

Table 6. Mold bread spoilage during incubation of the baked breads at 30 °C and at room temperature (RT).

		24 h		48 h		72 h		96 h
Bread	T (°C)	Degree of spoilage	Odour	Degree of spoilage	Odour	Degree of spoilage	Odour	Degree of spoilage	Odour
Control (without sourdough)	RT	–	No	–	No	–	No	I	Yes
	30	–	No	–	No	–	No	I	Yes
Two-strain starter sourdough 10%	RT	–	No	–	No	–	No	I	Yes
	30	–	No	–	No	–	No	I	Yes
Two-strain starter sourdough 15%	RT	–	No	–	No	–	No	–	No
	30	–	No	–	No	–	No	–	No
Four-strain starter sourdough 10%	RT	–	No	–	No	–	No	–	No
	30	–	No	–	No	–	No	–	No
Four-strain starter sourdough 15%	RT	–	No	–	No	–	No	–	No
	30	–	No	–	No	–	No	–	No