title: Volatile metabolites produced from agro-industrial wastes by Na-alginate entrapped Kluyveromyces marxianus.
abstract: The aim of this study was to evaluate the effects of alginate entrapment on fermentation metabolites of Kluyveromyces marxianus grown in agrowastes that served as the liquid culture media. K. marxianus cells entrapped in Na-alginate were prepared using the traditional liquid-droplet-forming method. Whey and pomaces from processed tomatoes, peppers, and grapes were used as the culture media. The changes in the concentrations of sugar, alcohol, organic acids, and flavor compounds were analyzed using gas chromatography-mass spectrometry (GC-MS) and high pressure liquid chromatography (HPLC). Both free and entrapped, K. marxianus were used individually to metabolize sugars, organic acids, alcohols, and flavor compounds in the tomato, pepper, grape, and acid whey based media. Marked changes in the fermentation behaviors of entrapped and free K. marxianus were observed in each culture. A 1.45-log increase was observed in the cell numbers of free K. marxianus during fermentation. On the contrary, the cell numbers of entrapped K. marxianus remained the same. Both free and entrapped K. marxianus brought about the fermentation of sugars such as glucose, fructose, and lactose in the agrowaste cultures. The highest volume of ethanol was produced by K. marxianus in the whey based media. The concentrations of flavor compounds such as ethyl acetate, isoamyl alcohol, isoamyl acetate, 2-phenylethyl isobutyrate, phenylethyl acetate, and phenylethyl alcohol were higher in fermented agrowaste based media compared to the control.
authors: Uşak University, Engineering Faculty, Department of Food Engineering, 1 Eylül Campus, Uşak, Turkey. Electronic address: onur.guneser@usak.edu.tr.
authors: Onur
authors: O
authors: Güneşer
authors: Çanakkale Onsekiz Mart University, Engineering Faculty, Department of Food Engineering, Çanakkale, Turkey.
authors: Yonca
authors: Y
authors: Karagül-Yüceer
authors: Lodz University of Technology, Institute of Fermentation Technology and Microbiology, Lodz, Poland.
authors: Agnieszka
authors: A
authors: Wilkowska
authors: Lodz University of Technology, Institute of Fermentation Technology and Microbiology, Lodz, Poland.
authors: Dorota
authors: D
authors: Kregiel
mesh_terms: D000464:Alginates / Q000378:metabolism*; D001673:Biodegradation, Environmental; D005285:Fermentation; D020723:Glucuronic Acid / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D007220:Industrial Waste; D007716:Kluyveromyces / Q000378:metabolism*; D055549:Volatile Organic Compounds / Q000378:metabolism*; D014866:Waste Products
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D007220:Industrial Waste; D055549:Volatile Organic Compounds; D014866:Waste Products; D020723:Glucuronic Acid
keywords: Agrowastes; Encapsulation; Foamed alginate; Kluyveromyces marxianus