Skin-contact fermented white wines, the so-called orange or qvevri wines, have been gaining international attention from winemakers, importers, sommeliers, consumers, and journalists over the last 10 years. Sommeliers are now regularly pairing orange wines with fine cuisine. This new culinary trend is part of a general move by the consumer wishing to respect the existence of traditions and innovation, combined with a growing interest in environmental awareness and healthy options. Orange wines are made from white grapes using ancient Georgian techniques. The essence of this method is the long skin-contact fermentation in amphorae without any chemicals or specific yeast. In our work, the polyphenol content of orange wines, in particular total polyphenol and catechin content, as well as colour intensity were measured to ensure safe winemaking technology without oxidized components.
Cornmeal agar (CMA) is a good to model natural conditions (low C and N, high antioxidants, crude fat) for phytopathogenic fungi. Different CMA media was prepared to model the maize kernel as growth environment for Aspergillus flavus, where stress resistance and aflatoxin B1 (AFB1) production were tested. The CMA medium with high polyphenol and low fatty acid content did not support the mycelial growth and high AFB1 production but the sclerotia development of the cultures. High fatty acid content in the CMA exceeded the inhibitory effect of antioxidant polyphenols of corn and low concentration of AFB1 was detected. Glucose supplement of CMA induced AFB1 production proving the need for free carbon source for the secondary metabolite pathway. The tolerance of the fungus against salt and cell membrane stress was lowered on CMA. At higher fatty acid concentration, the aflatoxin B1 production cannot be hindered by the natural antioxidants and that is important in selection of resistant corn hybrids.
, J. , Sánchez-González , C. , Vallverdú-Queralt , A. , Simal-Gándara , J. , Lamuela-Raventós , R. & Izquierdo-Pulido , M. ( 2014 ): Comprehensive identification of walnut polyphenols by liquid chromatography coupled
Authors:T. Tóth, J. Kovarovič, J. Bystrická, A. Vollmannová, J. Musilová and M. Lenková
, M. , Bystrická , J. , Tóth , T. & Hrstková , M. ( 2016 ): Evaluation and comparison of the content of total polyphenols and antioxidant activity of selected species of the genus Allium . Journal of Central European
dehydrofreezingversus conventional freezing of apple fruit. The impacts of frozen storage at -18 °C for 18 months on the amount of water exuded during thawing, the colour, and the total polyphenol content of the thawed fruit were studied. 1 Materials and methods 1