Utjecaj dodatka laktoferina i lizozima izoliranih iz mlijeka magarice na svojstva jogurta

Food industry has mostly focused on natural preservatives due to the undesirable effects of chemical additives on the human health. Among milk proteins, lactoferrin and lysozyme are the best-known for their antimicrobial. In this study, lactoferrin and lysozyme were extracted from donkey milk and applied on the yoghurt surface by spraying. The obtained yoghurt samples enriched with antimicrobial proteins were compared with the control sample produced without the addition of any preservatives as well as the samples treated with natamycin, a commercial preservative used in dairy products. Thereby physicochemical, microbiological and textural properties of the samples were investigated during the 30 days of storage. Yoghurt samples treated with antimicrobial agents had lower microbial load than control samples, which indicated that the donkey milk lactoferrin and lysozyme inhibit microbial activity in yoghurts. However, the addition of the mentioned preservatives did not change the gross composition and the textural properties of the yoghurt samples. Most importantly, the incorporation of lactoferrin or lysozyme did not adversely affect the sensory properties of yoghurt samples, but achieved higher appreciation points than the control sample on the 30th day of storage. In brief, lactoferrin and lysozyme extracted from donkey milk could be used to control the undesirable microbial growth, hence extending the shelf life of yoghurt.Zbog neželjenih učinaka kemijskih konzervansa na zdravlje ljudi, prehrambena se industrija uglavnom usredotočila na primjenu prirodnih konzervansa. Laktoferin i lizozim ubrajaju se u mliječne proteine najjačeg antimikrobnog djelovanja. U ovom su istraživanju ti proteini izolirani iz mlijeka magarice te prskanjem naneseni na površinu jogurta. Tako dobiveni uzorci jogurta obogaćeni proteinima s antimikrobnim djelovanjem uspoređivani su s kontrolnim uzorkom proizvedenim bez dodatka ikakvih konzervansa, kao s i uzorcima tretiranim natamicinom kao komercijalnim konzervansom, a koji se često koristi u mliječnim proizvodima. Svim uzorcima su ispitivana fizikalno-kemijska, mikrobiološka i teksturalna svojstva tijekom 30 dana skladištenja. Prema dobivenim rezutatima, uzorci jogurta tretirani antimikrobnim sredstvima imali su manje mikroorganizama od kontrolnog uzorka, što ukazuje da laktoferin i lizozim izolirani iz mlijeka magarice djeluju inhibitorno na mikrobnu aktivnost u uzorcima jogurta. S druge strane, dodatak spomenutih konzervansa nije promijenio sastav ni teksturalna svojstva ispitivanih uzoraka jogurta. Međutim, najvažniji rezultati odnose se na senzorska svojstva jogurta koja su ostala nepromijenjena odnosno dodatak laktoferina ili lizozima nije negativno utjecao na njih. Naprotiv, jogurti s dodatkom laktoferina ili lizozima su nakon 30 dana skladištenja bolje ocijenjeni od kontrolnog uzorka. Uzimajući sve rezulatte u obzir, laktoferin i lizozim izolirani iz mlijeka magarice mogli bi se koristiti za kontrolu rasta neželjenih mikroorganizama te za produljenje roka trajanja jogurta

A model for implementation of HACCP system for prevention and control of mycotoxins during the production of red dried chili pepper

Abstract Hazard analysis and critical control points (HACCP) is a process control system describes the potential hazards during food production flow chart. In contrast to the conventional way of ensuring product safety by end-product testing, HACCP establishes control systems, focuses mainly on preventive measures. Quality of red dried chili pepper (RDCP) should be assured by taking special care from harvesting of the peppers to retailing of the packaged product. RDCP is susceptible to fungi growth and mycotoxin contamination depending on the atmospheric and processing conditions such as humidity, temperature, storage and drying. Mycotoxins, are toxic metabolites to human health and strict control measures are required for preventing their occurrence in RDCP. In this study, HACCP system was implemented during the production of RDCP to ensure the food safety and quality characteristics of products and to expand the market. The most important critical control points (CCPs) during the production of RDCP was determined as sorting and drying. It is evident that development and use of the GMP, GAP, GSP and hygienic rules as well as HACCP during handling and processing of dry chili pepper are a must for processing plants

A model for implementation of HACCP system for prevention and control of mycotoxins during the production of red dried chili pepper

<div><p>Abstract Hazard analysis and critical control points (HACCP) is a process control system describes the potential hazards during food production flow chart. In contrast to the conventional way of ensuring product safety by end-product testing, HACCP establishes control systems, focuses mainly on preventive measures. Quality of red dried chili pepper (RDCP) should be assured by taking special care from harvesting of the peppers to retailing of the packaged product. RDCP is susceptible to fungi growth and mycotoxin contamination depending on the atmospheric and processing conditions such as humidity, temperature, storage and drying. Mycotoxins, are toxic metabolites to human health and strict control measures are required for preventing their occurrence in RDCP. In this study, HACCP system was implemented during the production of RDCP to ensure the food safety and quality characteristics of products and to expand the market. The most important critical control points (CCPs) during the production of RDCP was determined as sorting and drying. It is evident that development and use of the GMP, GAP, GSP and hygienic rules as well as HACCP during handling and processing of dry chili pepper are a must for processing plants.</p></div

Temporal microbiota and biochemical profiles during production and ripening of Divle Cave cheese

The aim of this study was to evaluate the proteolysis and lipolysis profiles of a raw ewes' milk cheese during production and ripening. The microbial community of this cheese was quantified, and their roles during proteolysis and lipolysis were studied. We observed an accumulation of substantial amounts of peptides during ripening, which might be attributed to the abundant presence of lactic acid bacteria, as well as to secondary microbiota including fungi, yeasts and actinobacteria. Similarly, high lipolysis levels were obtained, which can be explained by the indigenous lipase in milk and microbial lipases. These results should be of great interest to industrial manufacturers of this cheese

Temporal microbiota and biochemical profiles during production and ripening of Divle Cave cheese

The aim of this study was to evaluate the proteolysis and lipolysis profiles of a raw ewes' milk cheese during production and ripening. The microbial community of this cheese was quantified, and their roles during proteolysis and lipolysis were studied. We observed an accumulation of substantial amounts of peptides during ripening, which might be attributed to the abundant presence of lactic acid bacteria, as well as to secondary microbiota including fungi, yeasts and actinobacteria. Similarly, high lipolysis levels were obtained, which can be explained by the indigenous lipase in milk and microbial lipases. These results should be of great interest to industrial manufacturers of this cheese

A genomic survey of proteases in Aspergilli

BACKGROUND: Proteases can hydrolyze peptides in aqueous environments. This property has made proteases the most important industrial enzymes by taking up about 60% of the total enzyme market. Microorganisms are the main sources for industrial protease production due to their high yield and a wide range of biochemical properties. Several Aspergilli have the ability to produce a variety of proteases, but no comprehensive comparative study has been carried out on protease productivity in this genus so far. RESULTS: We have performed a combined analysis of comparative genomics, proteomics and enzymology tests on seven Aspergillus species grown on wheat bran and sugar beet pulp. Putative proteases were identified by homology search and Pfam domains. These genes were then clusters based on orthology and extracellular proteases were identified by protein subcellular localization prediction. Proteomics was used to identify the secreted enzymes in the cultures, while protease essays with and without inhibitors were performed to determine the overall protease activity per protease class. All this data was then integrated to compare the protease productivities in Aspergilli. CONCLUSIONS: Genomes of Aspergillus species contain a similar proportion of protease encoding genes. According to comparative genomics, proteomics and enzymatic experiments serine proteases make up the largest group in the protease spectrum across the species. In general wheat bran gives higher induction of proteases than sugar beet pulp. Interesting differences of protease activity, extracellular enzyme spectrum composition, protein occurrence and abundance were identified for species. By combining in silico and wet-lab experiments, we present the intriguing variety of protease productivity in Aspergilli