Proteolysis in model sourdough fermentations.
Model wheat doughs started with six different lactic acid bacteria (LAB), with or without a commercial baker's yeast culture, were used to study proteolysis in sourdough fermentations. Cell counts, pH, and free amino acid concentration were measured. Sequential extraction of dough samples was performed to separate wheat proteins. The salt-soluble protein fraction (albumins and globulins) was analyzed by RP-HPLC and SDS-PAGE, whereas propanol-soluble (gliadins) and insoluble (glutenins) protein fractions were analyzed by SDS-PAGE only. Multivariate statistical methods were used for the analysis of results. The presence of yeasts and LAB affected RP-HPLC and SDS-PAGE patterns of the salt-soluble fraction in a complex way. The only changes in the gluten proteins that could be related to the presence of LAB were the appearance of new protein fragments (20 and 27 kDa) from gliadins and the degradation of high molecular weight glutenin subunits.
Dipartimento di Biologia, Difesa e Biotecnologie Agro-Forestali, Università degli Studi della Basilicata, Campus di Macchia Romana, 85100 Potenza, Italy. fs543agr@unibas.it
Teresa
T
Zotta
Paolo
P
Piraino
Annamaria
A
Ricciardi
Paul L H
PL
McSweeney
Eugenio
E
Parente
D000704:Analysis of Variance; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism; D001939:Bread; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation; D005903:Gliadin / Q000032:analysis / Q000378:metabolism; D005983:Glutens / Q000032:analysis / Q000378:metabolism; D006868:Hydrolysis; D007778:Lactobacillus / Q000254:growth & development / Q000378:metabolism; D007934:Leuconostoc / Q000254:growth & development / Q000378:metabolism; D010447:Peptide Hydrolases / Q000378:metabolism*; D012995:Solubility; D014908:Triticum
D005983:Glutens; D005903:Gliadin; D010447:Peptide Hydrolases; C037302:glutenin