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.

Influence of Different Aggregation States on Volatile Organic Compounds Released by Dairy Kluyveromyces marxianus Strains

“…Biofilm-detached cells produced lower levels of 2-PEA (15.39 mg/L). In this study, it was found that K. marxianus yeast biofilm-detached cells produced 2-phenethyl butanoate, and phenethyl isobutyrate which are usually found in low amounts and are sought after by the food industries for their sensory impact on foods [ 33 ]. Ketones and phenols were produced only by biofilm-detached cells.…”

“…Phenethyl propionate (rose, floral, honey) is commonly not synthesized by S. cerevisiae . The production of this compound has been described in some non- Saccharomyces such as L. thermotolerans , Torulaspora delbrueckii , and K. marxianus [ 33 , 42 ]. In particular, Güneser et al [ 33 ] evaluated the effects of alginate entrapment on fermentation metabolites of K. marxianus grown in agrowastes that served as the liquid culture media.…”

“…The production of this compound has been described in some non- Saccharomyces such as L. thermotolerans , Torulaspora delbrueckii , and K. marxianus [ 33 , 42 ]. In particular, Güneser et al [ 33 ] evaluated the effects of alginate entrapment on fermentation metabolites of K. marxianus grown in agrowastes that served as the liquid culture media. These authors observed that phenethyl propionate was mainly produced when K. marxianus cells were entrapped.…”

Cheese whey permeate valorization using sequential fermentations: case study performed in the Western Region of Paraná

“…The highest pH decrease was observed in runs 3, 4, 7-11, in which the initial pH was higher (5.5-6.5), which can also mean that those conditions enabled not only ethanol production but also secondary metabolites, which is undesirable when ethanol is the main product of interest (Güneser, Karagül-Yüceer, Wilkowska, & Kregiel, 2016). Organic acids were identified in the runs, with concentrations in the range of: 0.5 to 5 g L -1 (AA), 1 to 3 g L -1 (propionic), 0.5 to 2.5 g L -1 (valeric), 0.5 to 6 g L -1 (lactic), 0.5 to 3 g L -1 (formic), and 0.5 to 2.3 g L -1 (butyric).…”

Kluyveromyces marxianus, sus aplicaciones en lactosuero

“…A pesar de que en esta sección, uno de los objetivos principales es la producción de etanol, la identificación y cuantificación de los compuestos volátiles generados es fundamental para las características organolépticas de la bebida (Dragone et al, 2009). En estas bebidas se identificaron compuestos de sabor tales como alcohol isoamílico (plátano), acetato de isoamilo (afrutado, plátano), alcohol feniletílico (rosa), acetato de feniletilo (floral), entre otros (Dragone et al, 2009;Gantumur et al, 2022;Guneser et al, 2016;Risner, Tomasino, Hughes, & Meunier-Goddik, 2019). La productividad de los compuestos volátiles depende del tipo de residuos agrícolas (Guneser et al, 2016).…”