Table 1.
Sourdough propagation parameters (fermentation temperature and time, inoculum size, dough yield), starter used to initiate fermentation, and sampling schedule in four Estonian bakeries (Abakery, Bbakery, Cbakery and Dbakery).
In Cbakery and Dbakery the fermentation was carried out at room temperature (RT). ‘Months’ indicate time passed from the beginning of a new sourdough cycle (Abakery, Bbakery, and Cbakery) or from the collection of the first sourdough sample (Dbakery).
Table 2.
Mean values ± standard deviation of pH, total titratable acidity (TTA) and cell density of presumptive lactic acid bacteria (LAB) of rye sourdoughs from four Estonian bakeries (Abakery, Bbakery, Cbakery and Dbakery).
Samples are coded according to the description reported in Table 1.
Fig 1.
Composition of lactic acid bacterium species, expressed in percentage of the total number of isolates, in rye sourdoughs from four Estonian bakeries (Abakery, Bbakery, Cbakery and Dbakery).
Samples are coded according to the description reported in Table 1.
Fig 2.
Relative abundance of bacterial species/genera detected in rye sourdoughs from four Estonian bakeries (Abakery, Bbakery, Cbakery and Dbakery) using pyrosequencing of 16S rRNA gene amplicons.
Samples are coded according to the description reported in Table 1.
Table 3.
Bacterial species/genera found in the rye sourdough samples from four Estonian bakeries (Abakery, Bbakery, Cbakery and Dbakery) through culture dependent analysis, DGGE or 16S pyrosequencing.
Presence (+) or absence (‒) of species is indicated for each sample in the following order: culture dependent analysis / DGGE / 16S pyrosequencing. N–not analyzed. Samples are coded according to the description reported in Table 1.
Table 4.
Number of reads, OTUs, expected OTUs at 500 reads and rate of new OTUs at 500 reads obtained from 16S rRNA pyrosequencing of rye sourdoughs from four Estonian bakeries (Abakery, Bbakery, Cbakery and Dbakery).
Samples are coded according to the description reported in Table 1.
Fig 3.
pH (red plot) and lactic acid bacterium species detected by DGGE analysis of the 16S rRNA gene amplicons in rye sourdoughs collected at the Dbakery before (D4) and after applying the new propagation protocol.
Time after transfer is indicated below the gel (d–day; m–month). Bands: 1, 7 –Lactobacillus helveticus; 2, 8 –Cereal chloroplast DNA; 3, 4, 5, 10 –Lactobacillus pontis; 6 –Lactobacillus sp.; 9 –Lactobacillus zymae; *—sample collected from sourdough after 36 h storage at 5°C.
Fig 4.
Two dimensional non-metric multidimensional scaling (NMDS) of sourdough samples from four Estonian bakeries (Abakery, Bbakery, Cbakery and Dbakery).