Preservation of pears in water in the presence of Sinapis arvensis seeds: a Greek tradition

Enhancement of Textural and Sensory Characteristics of Wheat Bread Using a Chickpea Sourdough Fermented with a Selected Autochthonous Microorganism

A traditional Greek sourdough, based on the fermentation of chickpea flour by an autochthonous culture, was evaluated as a wheat bread improver. The dominant indigenous microflora (Clostridium perfringens isolates) was identified by 16S rDNA analysis, and a selected strain (C. perfringens CP8) was employed to ferment chickpea flour to obtain a standardized starter culture (sourdough) for breadmaking. In accordance with toxin-typed strain identification, all isolates lacked the cpe gene; thus, there is no concern for a health hazard. Loaf-specific volumes increased with the addition of liquid, freeze-dried, and freeze-dried/maltodextrin sourdoughs compared to control bread leavened by baker's yeast only. Following storage (4 days/25 °C), the amylopectin retrogradation and crumb hardness changes (texture profile analysis) revealed a lower degree of staling for the sourdough-fortified breads. Modifications in the protein secondary structure of fortified doughs and breads were revealed by FTIR analysis. High amounts of organic acids were also found in the sourdough-supplemented breads; butyric and isobutyric acids seemed to be responsible for the characteristic 'butter-like' flavor of these products (sensory analysis). Overall, the addition of liquid or freeze-dried chickpea sourdough in wheat bread formulations can improve the specific volume, textural characteristics, and sensorial properties of loaves, along with extending bread shelf life.

Isolation of antifungal activity of Leuconostoc mesenteroides TA from kimchi and characterization of its antifungal compounds

Strain TA harboring antifungal activity was isolated from kimchi and identified based on Gram-staining, biochemical properties using an API 50 CHL, determination of rRNA gene sequences, and RAPD analysis. The determined gene sequences and RAPD pattern showed 100% homology with those of Leuconostoc mesenteroides ATCC 8293^T. However, their properties were slightly different from each other. Especially, TA could not utilize lactose while strain ATCC 8293 could use lactose. Leu. mesenteroides ATCC 8293 showed higher antibacterial activity against Bacillus cereus than Leu. mesenteroides TA, whereas the antifungal activities of these 2 LAB against Aspergillus fumigatus were the same. Leu. mesenteroides TA showed broad antimicrobial activities against Gram-positive and - negative bacteria as well as molds. We determined that the responsible antifungal compounds from Leu. mesenteroides TA are lactic acid, acetic acid and unidentified hydrophobic compound(s). Additionally, synergistic interactions involving acetic acid, lactic acid, phenyllactic acid, and unidentified hydrophobic compound(s) contribute to the overall inhibitory activity of Leu. mesenteroides TA.