1. Functional characterization of Saccharomyces yeasts from cider produced in HardangerUrban Česnik, Mitja Martelanc, Ingunn Ovsthus, Tatjana Radovanović Vukajlović, Ahmad Hosseini, Branka Mozetič Vodopivec, Lorena Butinar, 2023, izvirni znanstveni članek Ključne besede: Saccharomyces, Hardanger, characterization, fermentation, cider, non-volatile compounds, volatile organic compounds, partial least squares regression
Objavljeno v RUNG: 18.09.2023; Ogledov: 1634; Prenosov: 9
 Celotno besedilo (4,79 MB)
Gradivo ima več datotek! Več... |
2. SCREENING AND EVALUATION OF ENZYMATIC ACTIVITIES OF WINE RELATED YEAST SPECIESAdesida Rowland, Melita Sternad Lemut, Lorena Butinar, 2020, objavljeni povzetek znanstvenega prispevka na konferenci Opis: A number of indigenous yeast strains isolated from vineyard / cellar-associated samples and non-vineyard sites, from forests with oak trees (a known habitat where Saccharomyces species resides) from existing in-house yeast collection and from ZIM culture collections (Slovenia) were screened for enzymatic activities with enological importance. The yeasts were screened for glycosidase enzymes connected to terpene aroma release, the β-lyase activity responsible for the volatile thiol release, and sulfite reductase activity involved in off-flavours. Yeast strains that showed positive results for qualitative and quick detection of glucoside hydrolase activity on plates were selected for further studies. The glucoside hydrolase activity of 20 selected strains belonging to 15 different species was quantitatively characterized by determinations of the activity on pNPG. All strains demonstrated hydrolase activity, especially strain H. uvarum 116 which showed the highest value of specific activity 6.32 mU/mg for cell-associated activity and T. delbrueckii Sut 94 with highest value of specific activity 1.36 mU/mg for extracellular activity. Increased growth of tested yeast on medium containing substrate S-methyl-L-cysteine indicated β-lyase activity, and by this approach a moderate activity was recorded throughout our tested strains with immense intraspecific inconsistency. Noticeable H2S production was observed in P. manshurica strain whereas, H. uvarum, L. thermotolerance, S. bayanus and S. cerevisiae demonstrated weak/slight H2S-producer strains in our study. Therefore, our screening indicates the importance of strain selection for enological application due to intraspecies differences, as well as the introduction of non-Saccharomyces yeast starters with interesting potential to enhance wine aroma.
Ključne besede: wine yeasts, non-Saccharomyces, enzymatic activities
Objavljeno v RUNG: 08.05.2023; Ogledov: 1736; Prenosov: 0
Gradivo ima več datotek! Več... |
3. Novel analytical approaches in quality and safety control in production of fermented beverages : dissertationJelena Topić, 2022, doktorska disertacija Opis: The exploitation of microorganisms for fermentation goes back centuries. Two types of fermentation are usually used in the winemaking process – alcoholic fermentation and malolactic fermentation. Nowadays, inoculated fermentations with the use of starter cultures are commonly used in order to produce wine with more consistent quality. However, wines can lack in flavour complexity, so scientists and the industry are constantly looking for new and improved starters that can be adapted to different types of wine.
In this work we focused on the development and implementation of novel analytical methods for wine quality control. In the course of method development native yeasts and lactic acid bacteria isolates were characterized for wine starter properties. We focused on the determination of biologically active compounds that determine wine quality and safety. Yeasts can influence wine colour through their adsorption capacity and synthesis of stable colour pigments pyranoanthocyanins and lactic acid bacteria can produce biogenic amines which can have adverse detrimental health effects on sensitive consumers when they are present in wines.
Ključne besede: Saccharomyces yeasts, non-Saccharomyces yeasts, pyranoanthocyanins, thermal-lens spectrometry, lactic acid bacteria, biogenic amines, thin layer chromatography, dissertations
Objavljeno v RUNG: 18.02.2022; Ogledov: 3847; Prenosov: 156
 Povezava na celotno besedilo
Gradivo ima več datotek! Več... |
4. The influence of selected indigenous yeasts on Pinot Noir wine colour propertiesJelena Topić, Lorena Butinar, Guillaume Antalick, Melita Sternad Lemut, Mitja Martelanc, Alen Albreht, Dorota Korte, Branka Mozetič Vodopivec, 2021, izvirni znanstveni članek Ključne besede: Pinot Noir, wine colour, yeasts, non-Saccharomyces, sensory
Objavljeno v RUNG: 07.07.2021; Ogledov: 3004; Prenosov: 0
Gradivo ima več datotek! Več... |
5. |
6. Uporaba različnih kvasovk v pridelavi jabolčnega vinaLuka Koporec, 2018, diplomsko delo Opis: Kemijske in senzorične lastnosti vina so poleg genetskih danosti ter geo-klimatskih okoliščin odvisne tudi od strategije tehnologije pridelave, ki jo izbere vinar. V to strategijo spada tudi izbira seva kvasovke. Vinski trg postaja vse bolj zahteven in željan nečesa novega, zato vse več vinarjev poskuša pridobiti drugačne lastnosti vin z uporabo drugačnih sevov kvasovk, oziroma z uporabo kombinacij različnih vrst kvasovk. V diplomski nalogi smo preučevali vpliv različnih kombinacij kvasovk na potek fermentacije ter na osnovne kemijske in senzorične lastnosti pridelanega jabolčnega vina. Poskus je bil izveden na laboratorijski skali. Rezultati poskusa so pokazali, da različne vrste kvasovk različno vplivajo na senzorične lastnosti vina, nekoliko manj pa na kemijske lastnosti. Rezultati nakazujejo, da različne kvasovke različno hitro porabljajo sladkorje, kar vpliva tudi na hitrost poteka fermentacije. Ob opazovanju osnovnih kemijskih lastnostih smo opazili razlike med kvasovkami oz. kombinacijami kvasovk pri parametrih kot so hlapne kisline in reducirajoči sladkorji, medtem ko v vsebnosti alkohola in pH vrednostih končnih jabolčnih vin med obravnavanimi fermentacijami nismo opazili razlik. Senzorična analiza vonja in barve jabolčnih vin je potrdila vpliv kvasovk na barvo, intenzivnost, trajnost in vrsto vonja.
Ključne besede: jabolčno vino, ne-Saccharomyces kvasovke, potek fermentacije, kvasovke, senzorična analiza
Objavljeno v RUNG: 26.10.2018; Ogledov: 8113; Prenosov: 225
Celotno besedilo (1,34 MB) |
7. |
8. |
