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Pozycja Anti-adhesion activity of mint (Mentha piperita L.) leaves extract against beverage spoilage bacteria Asaia spp.(Lodz University of Technology Press, 2016) Antolak, Hubert; Czyżowska, Agata; Kręgiel, DorotaThe production of a functional beverage, supplemented with fruit flavourings meets the problem of microbiological contamination. The most frequent source of such spoilage is the bacteria from the relatively newly discovered genus Asaia. It causes changes in organoleptic properties, creating turbidity, haziness and distinctive sour odour as well as biofilm on production lines which are responsible for secondary contamination of products. For this reason, new methods using natural preservatives are being developed to minimize this microbiological contamination. The application of some plant extracts as an additives in functional beverages production is presumed to have a beneficial effect on reducing adhesive abilities of the bacteria. The aim of this research was to investigate the effects of mint leaves extract on the Asaia lannensis and Asaia bogorensis adhesive abilities to polystyrene. The bacterial adhesion was analysed by means of plate count method and luminometric tests. Additionally, plant extract was subjected to high performance liquid chromatography (HPLC) analysis, in order to check polyphenols content. Results indicates that 10% (v/v) addition of mint extract significantly reduced Asaia spp. adhesion to polystyrene. Due to the presence of bioactive compounds in the used extract, it can be used as an additive to increase microbiological stability as well as health promoting values of beverages.Pozycja The impact of commercial polyphenolic extracts on meat spoilage bacteria(Lodz University of Technology Press, 2015) Nowak, Agnieszka; Czyżowska, AgataAccording to Regulation 178/2002 (EU) spoiled food is considered unsafe. One of the most susceptible to microbial spoilage products are raw and processed meat. Because of its rich chemical composition, high water activity and pH, meat is an excellent habitat for numerous microorganisms [1]. The combination of VP, MAP and natural antimicrobial agents could be very promising Polyphenols can be potentially used as natural preservatives. They have been reported to have a variety of biological effects including antimicrobial activities. The aim of the study was the investigation of influence of black carrot and red cabbage extracts on meat spoilage bacteria.Pozycja Fermented unripe cornelian cherry as a functional food(Lodz University of Technology Press, 2015) Czyżowska, Agata; Kucharska, Alicja; Nowak, Agnieszka; Motyl, IlonaConsumer trends are changing due to the increasing awareness of the link between diet and health. The largest segment of the functional food market comprises foods fortified with probiotics, prebiotics and synbiotics. Fruits already containing high levels of beneficial substances can be reinforced with probiotic bacteria that can bring about additional health promoting features. Cornelian cherry (Cornus mas L.) fruits are rich sources of polyphenols and iridoids, valuable for fresh consumption or processing. Unripe fruits is manufactured by Arboretum in Bolestraszyce as a traditional product. The aim of this work was to evaluate the probiotic strains in order to determine their potential in the development of new starter cultures for functional food – green fermented cornelian cherry.Pozycja Ciders as a source of bioactive compounds(Lodz University of Technology Press, 2015) Czyżowska, Agata; Nowak, Agnieszka; Żaworonek, MarcinPoland is one of the main producers of apples in Europe. The major part is consumed fresh, while a smaller is processed into juices, concentrates, purees or wines. Recently also the production of cider started in Poland. This fermented drink is produced in countries with a long tradition of drinking cider from the so-called cider varieties of apples. In our country, these varieties are rare. Therefore, the aim of this work is to check the suitability of selected domestic varieties of apples for cider production and evaluate the content of polyphenol compounds.Pozycja Effect of nitrogen sources on fermentation process and formation of hydrogen sulfide and ethyl carbamate by wine yeast(Wydawnictwo Politechniki Łódzkiej, 2013) Nowak, Agnieszka; Koch-Wilk, Magdalena; Pogorzelski, Eugeniusz; Czyżowska, AgataThe addition of nitrogen compounds during winemaking is required for the fermentation process to be conducted properly. These compounds are known to be essential to the vinification process, not only because they influence yeast growth but also because they affect the formation of main and by-products. The effect of nitrogen source on in vitro and in situ formation of hydrogen sulfide and ethyl carbamate was studied. Research material comprised two strains of wine yeast: Saccharomyces cerevisiae. In vitro model was carried out in a synthetic defined medium. In situ fermentations were carried out in musts prepared from apple concentration. The process of hydrogen sulfide formation was intensified in nitrogen deficiency. The presence of amino acids in a model substrate resulted in significant changes in the efficiency of formation of both compounds. Yeasts produced more H2S in the presence of Cys, Phe, Gly, Glu, Ile, Thr, Pro, Leu, Trp, Val and less in the presence Ala, Arg, Asp, His, Ser, Met. The formation of ethyl carbamate was limited by the amino acids, except Arg, Asp and Lys, which during fermentation with Syrena yeasts caused an increase in the efficiency of formation of this compound. The Fermivit V preparation stimulated yeasts to form H2S. In the presence of this preparation the Syrena yeasts formed more ethyl carbamate while Hefix yeasts formed about 3-fold less of this compound then in the presence diamonium phosphate.