Grape pomace application in environmental studies: from waste to natural food preservative and source of biofuel

The geographic location of Republic of Macedonia is exceptional for breeding vine and specific grape varieties. But, the wine industry waste in general is a problem in Macedonia, since it does not have any usage. In the European Union, there is approximately 14.5 million tons of wine industry waste produced from wineries (http://www.academicwino.com/2012/11/grape-seed-extract-leather-production.html). In fact, the wine industry waste (grape pomace) contains primarily crushed grape skins and seeds rich in beneficial polyphenol compounds that act as antioxidants, antibacterial agents etc. The largest fraction of winery waste is pomace, or the solid remains of grapes (skins, stalks and seeds), which is thrown away ending up in landfills. From another point of view, transport is the third largest emitter of greenhouse gases and biofuels can significantly reduce transport’s carbon footprint since it is dependent on finite fossil fuels such as oil and petroleum for its energy needs (R.E.H. Sims, et al.). Biodiesel, provides significantly reduced emissions of carbon monoxide; compared to petroleum diesel fuel

Grape pomace: from waste to natural food supplement and biodiesel

The purpose of this study was to introduce a new source of antioxidants obtained from grape pomace as well as aronia and blueberry and engages them in preparation of a new yoghurt product in order to be last – longer and more beneficial for human health than the traditional one. Totally, grape pomaces from 4 varieties (Zupjanka, Prokupec, Kadinal and Vranec), as well as blueberry and aronia, were used. For the extraction of polyphenols, liquid-liquid extraction with ethanol/water/acetic acid was used in order to concentrate phenols and introduce them into the milk. Three different concentrates of each sample (18 in total) were applied on milk together with lactic bacteria in order to study the influence of polyphenols during the fermentation; as well as, 18 other extracts applied on milk after the fermentation (into the obtained yoghurt). The pH value of the newly generated yoghurts was analyzed during the fermentation and storage. All yoghurt samples containing polyphenolics applied before the fermentation, presented higher pH value compared to the control and samples with polyphenolics applied after fermentation

Application of Grape Pomace as a Natural Food Preservative and Source of Biofuel

The aim of this work is utilization of the grape pomace piled up as a waste after winemaking and its application in producing biodiesel. Furthermore, a novel yoghurt product was produced, enriched with antioxidants, such as polyphenolics from the grape pomace and berries in order to improve its nutritional value, contributing to food preservation and significantly reducing the risk of diseases. In fact, for the first time we engaged these compounds in preparation of a new yoghurt product, that proved to be last ­ longer and more beneficial for human health than the traditional one, since the antioxidants play a great role in the prevention of cardiovascular disease, cancer etc. Furthermore, a cost- effective, easily made and environmentally friendly biodiesel was produced, that could represent an alternative to the old fossil petroleum to replace it and resolve the present energy crisis

Production of a new diary product enriched with antioxidants from grape pomace and berries

The purpose of this study was to introduce a new source of antioxidants obtained from grape pomace as well as aronia and blueberry and engages them in preparation of a new yoghurt product in order to be last – longer and more beneficial for human health than the traditional one. Totally, grape pomaces from 4 varieties (Zupjanka, Prokupec, Kadinal and Vranec), as well as blueberry and aronia, were used. For the extraction of polyphenolics, liquid-liquid extraction with ethanol/water/acetic acid was used, followed by roto-evaporation, in order to concentrate the extracts and then to introduce them into the milk. The total phenolic content of the extracts was determined by the Folin-Ciocalteu method and the total anthocyanins were analyzed by dilution of the samples with ethanol/water/HCl, obtaining three different volumes of extracts (10, 50 and 100 mL) of each sample (grape pomaces, blueberry and aronia), obtaining 36 extracts in total. The three different concentrates of each sample (18 in total) were applied on milk together with the lactic bacteria in order to study the influence of polyphenolics during the fermentation; as well as, 18 other extracts applied on milk after the fermentation (into the obtained yoghurt). The pH value of the newly generated yoghurts was analyzed during the fermentation and storage. The aronia sample presented highest phenolic content (431 mg/L), while Zupjanka had the lowest content of polyphenols (67.9 mg/L). The grape pomace presenting best results was Prokupec (246 mg/L). All yoghurt samples containing polyphenolics applied before the fermentation, presented higher pH value compared to the control and samples with polyphenolics applied after fermentation. Furthermore, all yoghurt samples containing phenolics extract with highest concentration, showed best results, presenting stable pH value. Sensory analysis was performed on the different yoghurt samples, concluding that the new products have creamy texture, good taste, without unpleasant smell or bitterness. The colour of some samples turned into red-violet, excluding the yoghurt with extracts from: Zupjanka and Kardinal. By microbiological analysis the presence of pathogen and other harmful bacterias was proved to be negative, showing that this yoghurt is a main basis for manufacturing of a more beneficial dairy product that could be soon available on the market