1. 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: 3873; Prenosov: 157 Povezava na celotno besedilo Gradivo ima več datotek! Več... |
2. Implementation of high performance liquid chromatography coupled to thermal lens spectrometry (HPLC‑TLS) for quantification of pyranoanthocyanins during fermentation of Pinot Noir grapesJelena Topič Božič, Lorena Butinar, Natka Ćurko, Karin Kovačević Ganić, Branka Mozetič Vodopivec, Dorota Korte, Mladen Franko, 2020, izvirni znanstveni članek Opis: In this work high performance liquid chromatography coupled to thermal lens spectrometry (HPLC-TLS) was applied for monitoring of vinylphenolic pyranoanthocyanins formation during the fermentation of Pinot Noir wines. Vinylphenolic pyranoanthocyanins are wine pigments, present in low concentrations, but very important for wine colour stability.
Fermentation process was conducted with four different yeast strains, used as starters, either in sequential fermentation of non-Saccharomyces with S. cerevisiae yeast or as single fermentation with S. cerevisiae yeasts in order to test the applicability of developed method for monitoring of selected compounds in real wine fermentation experiments. The
developed HPLC-TLS method showed higher sensitivity compared to HPLC coupled to diode array detection (DAD) technique for particular wine colour compounds. Obtained limits of detection (LODs), were 6- and 22-times lower in comparison to HPLC–DAD in gradient and isocratic elution mode, respectively, whereas limits of quantification (LOQs)
5 and 18-times lower. Lower LODs enabled earlier observation of vinylphenolic pyranoanthocyanins formation during fermentation (already at day 7) in the case of HPLC-TLS method in gradient mode, while by using HPLC–DAD in gradient elution mode the formation of vinylphenolic pyranoanthocyanins was noticed only after 12 days of fermentation. Ključne besede: Thermal lens spectrometry (TLS), High performance liquid chromatography (HPLC), Pyranoanthocyanins, Wine, Yeasts Objavljeno v RUNG: 18.06.2020; Ogledov: 4294; Prenosov: 0 Gradivo ima več datotek! Več... |
3. Synthesis of pyranoanthocyanins from Pinot Noir grape skin extract using fermentation with high pyranoanthocyanin producing yeasts and model wine storage as potential approaches in the production of stable natural food colorantsJelena Topić, Natka Ćurko, Karin Kovačević Ganić, Lorena Butinar, Alen Albreht, Irena Vovk, Dorota Korte, Branka Mozetič Vodopivec, 2020, izvirni znanstveni članek Ključne besede: Pyranoanthocyanins, Anthocyanins, Food colorants, Yeasts, Fermentation Objavljeno v RUNG: 03.04.2020; Ogledov: 4798; Prenosov: 0 Gradivo ima več datotek! Več... |
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