S. In all, 4379 isolates from 35 products, including 24 artisanal cheeses, were surveyed with a view to identifying strains that could be used as starters in commercial dairy fermentations. Of the isolates, 38 % were classified as Lactococcus, 17 % as Enterococcus, 14% as Streptococcus thermophilus, 12 % as mesophilic Lactobacillus, 10% as Leuconostoc and 9 % as thermophilic Lactobacillus. Acid production by the isolates varied considerably. Of the 1582 isolates of Lactococcus and 482 isolates of mesophilic Lactobacillus tested, only 8 and 2 % respectively produced sufficient acid to lower the pH of milk to 5n3 in 6 h at 30 mC. In contrast, 53, 32 and 13 % of Str. thermophilus, thermophilic Lactobacillus and Enterococcus isolates respectively reduced the pH to 5n3. These isolates were found only in some French, Italian and Greek cheeses. Bacteriocins were produced by 11 % of the 2257 isolates tested and 26 of them produced broad-spectrum bacteriocins which inhibited at least eight of the ten target strains used, which included lactic acid bacteria, clostridia and Listeria innocua. The most proteolytic of the 2469 isolates tested wereStr. thermophilus from Fontina cheese followed by Enterococcus from Fiore Sardo and Toma cheese and thermophilic Lactobacillus from all sources. Exopolysaccharides were produced by 5n3 % of the 2224 isolates tested.In many Southern European countries cheeses are made from cows', goats', ewes'

Angiotensin I converting enzyme (ACE) inhibitory and antioxidant peptides are receiving attention due to their beneficial effects in the prevention/treatment of hypertension. The objective was to explore the effect of high hydrostatic pressure (HP) on proteolysis by different proteases and the release of bioactive peptides from lentil proteins. Pressurisation (100-300 MPa) enhanced the hydrolytic efficiency of Protamex, Savinase and Corolase 7089 compared to Alcalase. Proteolysis at 300 MPa led to a complete degradation of lentil proteins and increased peptide (<3 kDa) concentration by all enzymes. Proteolysis at 300 MPa by Savinase gave rise to lentil hydrolysates (S300) with the highest ACE-inhibitory and antioxidant activities that were retained upon in vitro gastrointestinal digestion. The peptides responsible for the multifunctional properties of S300 hydrolysate were identified as different fragments from storage proteins and the allergen Len c 1. These results support the potential of HP as a technology for the cost-effective production of bioactive peptides from lentil proteins during enzymatic proteolysis.

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A total of 203 lactic acid bacteria isolated from raw goat's milk and artisanal cheese were tested for antibacterial activity. Only two strains of Lactococcus lactis, one strain of Enterococcus faecalis and one strain of Lactobacillus curvatus were shown to produce a bacteriocin‐like substance. Lactobacillus curvatus IFPL105 produced a heat‐stable bacteriocin, which was hydrolysed by α‐chymotrypsin, proteinase K and pancreatin and exhibited a broad spectrum of inhibitory activity. The bactericidal activity of the bacteriocin was more potent when sensitive strains were in the logarithmic growth phase, inducing cell lysis, as observed by decreases in optical density and release of intracellular marker enzymes. Curing experiments resulted in variants that lacked both bacteriocin activity and immunity to the bacteriocin. Plasmid profile analysis of the parental strain and the bacteriocin‐negative variants indicated that a plasmid of about 46 kbp may be involved in bacteriocin production and immunity to this antibacterial compound.

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