11. Food chemistry1976 Published in RUNG: 22.04.2022; Views: 1012; Downloads: 0 This document has many files! More... |
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14. High spatial heterogeneity of water stress levels in Refošk grapevines cultivated in Classical KarstFrancesco Petruzzellis, Sara Natale, Luca Bariviera, Alberto Calderan, Alenka Mihelčič, Jan Reščič, Paolo Sivilotti, Katja Šuklje, Klemen Lisjak, Andreja Vanzo, Andrea Nardini, 2022, original scientific article Keywords: Classical Karst, water status, drought stress, grape quality, phenolic profile, vitis vinifera Published in RUNG: 11.11.2021; Views: 1928; Downloads: 0 This document has many files! More... |
15. Opinions and measures on climate change in the vine and wine sector: a view on the future : presentation on a round table on climate change challenges, vine and wine sector, 10. 6. 2021, onlineJan Reščič, 2021, other performed works Abstract: Okrogla miza Keywords: podnebne spremembe, terroir, prilagoditve, sorte, temperatura, vinogradništvo, vinarstvo Published in RUNG: 16.06.2021; Views: 1935; Downloads: 0 This document has many files! More... |
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20. Occurence of biogenic amine - producing lactic acid bacteria in Refošk grape and wineJelena Topić Božič, Jan Reščič, Martina Bergant Marušič, Darja Lisjak, Branka Mozetič Vodopivec, Lorena Butinar, 2019, published scientific conference contribution abstract Abstract: Lactic acid bacteria (LAB) are naturally present in grapes, musts and wines. During malolactic fermentation, besides the beneficial conversion of L-malic to L-lactic acid, LAB can form also other compounds like biogenic amines (BAs). BAs are formed through decarboxylation of corresponding amino acids, through the action of enzymes. Consumption of food containing BAs can lead to food poisoning such as histamine poisoning. Histamine, the most studied BA, is known to cause headaches, oedema, vomiting.
In the last years, BAs associated pathways have been described as strain dependent and not as species dependent. Because of the high variability of microorganisms to decarboxylase amino acids, the detection of bacteria that have the possibility to transform precursor amino acid into BAs is very important in order to estimate the risk of BAs accumulation in wines. Since in previous years during project AGROTUR I we detected the higher BA content in some wines, we decided to focus on the presence of BA-producing LAB in Refošk grapes and wines. Therefore, during AGROTUR II project LAB collection of autochthonous lactic acid bacteria was set-up by isolating LAB from Refošk grapes and wines, originated from the grape growing cross-border region Karst (Slovenia). Over 600 isolates were obtained using MRS medium with added cycloheximide and 2% tomato juice. In parallel, also selective enrichment was performed using MRS medium described above with additionally added 5% ethanol. BA-producing LAB were primarily detected in microtiter-plate format using the decarboxylase screening medium with added amino acids (histidine, lysine, ornithine or tyrosine), which enable us to identify histamine-, cadaverine-, ornithine and tyrosine-producing LAB. Selected representatives from each BA-producing LAB groups were further on confirmed with chromatographic analysis (HPLC) and molecular methods (multiplex PCR method). BA-producing LAB were in majority represented by thyramin-producers, thereafter followed cadaverine-producers, with putrescine and histamine producers being the least presented. This screening of the BA-producing LAB is also incorporated in our on-going accurate selection of LAB starters for potential production of Refošk wines. Keywords: biogenic amines, lactic acid bacteria, refošk, grape, wine Published in RUNG: 22.01.2020; Views: 3308; Downloads: 0 This document has many files! More... |