Protease, peptidase and esterase activities by lactobacilli and yeast isolates from Feta cheese brine

Aims: The study of peptidase, esterase and caseinolytic activity of Lactobacillus paracasei subsp. paracasei, Debaryomyces hansenii and Sacchromyces cerevisiae isolates from Feta cheese brine. Methods and Results: Cell-free extracts from four strains of Lact. paracasei subsp. paracasei, four strains of D. hansenii and three strains of S. cerevisiae, isolated from Feta cheese brine were tested for their proteolytic and esterase enzyme activities. Lactobacillus paracasei subsp. paracasei strains had intracellular aminopeptidase, dipeptidyl aminopeptidase, dipeptidase, endopeptidase and carboxypeptidase activities. Esterases were detected in three of four strains of lactobacilli and their activities were smaller with higher molecular weight fatty acids. The strains of yeasts did not exhibit endopeptidase as well as dipeptidase activities except on Pro-Leu. Their intracellular proteolytic activity was higher than that of lactobacilli. Esterases from yeasts preferentially degraded short chain fatty acids. Lactobacilli degraded preferentially beta-casein. Caseinolytic activity of yeasts was higher than that of lactobacilli. Conclusions: The results suggest that Lact. paracasei subsp. paracasei and yeasts may contribute to the development of flavour in Feta cheese. Significance and impact of the Study: Selected strains could be used as adjunct starters to make high quality Feta cheese

White-brined cheeses

This chapter discusses various white-brined cheeses, including Batzos PDO, Turkish Beyaz Peynir, Feta, Halitzia, Halloumi, Mihalic, Sjenica, and Urfa. Turkish Beyaz Peynir is a rindless, white-coloured, close-textured variety with a salty acid taste; it may have a slight piquant flavour, especially when made from sheep's milk. A number of volatile compounds are produced by defined or wild-type lactococcal bacteria used in the manufacture of Turkish Beyaz Peynir. The geographical region of Sjenica cheese production is in the Sjenicko-Pesterska plateau, which is located in the southwestern part of Serbia and represents the biggest plateau in the Balkan, which includes the municipalities Sjenica and Tutin. Sjenica cheeses are home-made cheeses, manufactured at farms or produced in small dairy craft plants. Urfa cheese variety is mainly produced from raw sheep's milk (mainly milk of the Awassi sheep breed) or an appropriate mixture of sheep's and cow's milks. © 2018 John Wiley & Sons, Ltd. All rights reserved

Pasta-filata cheeses

This chapter discusses various kinds of Pasta-Filata cheeses, such as Caciocavallo Podolico PDO, Kachkaval, and Kashar. Kashkaval-type Kashar cheese is common in the Trakia region. Kashar cheese is a hard cheese with no holes but a rind, and it is yellowish in colour. Kasseri has a closed texture with no holes and a mild, mellow, faintly sweet flavour. The flavour is more pronounced when cheeses are well matured. Ragusano PDO is a stretched-curd cheese made with cow's raw whole milk. It is a high in fat and protein cheese, and it has a low moisture content when aged. Ragusano PDO has a parallelepiped shape with a square section and rounded corners. Parenica is a pasta-filata-type cheese, made from full-fat sheep's milk that is not heat-treated. The most characteristic feature of Parenica is its unique form of the double ribbon, as well as its stringy structure and attractive, softly acidic flavour with the sheep's milk overtones. © 2018 John Wiley & Sons, Ltd. All rights reserved

Pasta-filata cheeses

This chapter discusses various kinds of Pasta-Filata cheeses, such as Caciocavallo Podolico PDO, Kachkaval, and Kashar. Kashkaval-type Kashar cheese is common in the Trakia region. Kashar cheese is a hard cheese with no holes but a rind, and it is yellowish in colour. Kasseri has a closed texture with no holes and a mild, mellow, faintly sweet flavour. The flavour is more pronounced when cheeses are well matured. Ragusano PDO is a stretched-curd cheese made with cow's raw whole milk. It is a high in fat and protein cheese, and it has a low moisture content when aged. Ragusano PDO has a parallelepiped shape with a square section and rounded corners. Parenica is a pasta-filata-type cheese, made from full-fat sheep's milk that is not heat-treated. The most characteristic feature of Parenica is its unique form of the double ribbon, as well as its stringy structure and attractive, softly acidic flavour with the sheep's milk overtones

An evaluation of the infection control potential of a UV clinical podiatry unit

Background: Infection control is a key issue in podiatry as it is in all forms of clinical practice. Airborne contamination may be particularly important in podiatry due to the generation of particulates during treatment. Consequently, technologies that prevent contamination in podiatry settings may have a useful role. The aims of this investigation were twofold, firstly to determine the ability of a UV cabinet to protect instruments from airborne contamination and secondly to determine its ability to remove microbes from contaminated surfaces and instruments. Method: A UV instrument cabinet was installed in a University podiatry suite. Impact samplers and standard microbiological techniques were used to determine the nature and extent of microbial airborne contamination. Sterile filters were used to determine the ability of the UV cabinet to protect exposed surfaces. Artificially contaminated instruments were used to determine the ability of the cabinet to remove microbial contamination. Results: Airborne bacterial contamination was dominated by Gram positive cocci including Staphylococcus aureus. Airborne fungal levels were much lower than those observed for bacteria. The UV cabinet significantly reduced (p < 0.05) the observed levels of airborne contamination. When challenged with contaminated instruments the cabinet was able to reduce microbial levels by between 60% to 100% with more complex instruments e.g. clippers, remaining contaminated. Conclusions: Bacterial airborne contamination is a potential infection risk in podiatry settings due to the presence of S. aureus. The use of a UV instrument cabinet can reduce the risk of contamination by airborne microbes. The UV cabinet tested was unable to decontaminate instruments and as such could pose an infection risk if misused. Keywords: Infection control, UV, Bacteria, Fungi, Dermatophytes, Contaminatio