The occurrence, enzymatic production, and application of ethyl butanoate, an important flavor constituent

Abstract

Fermented food is loved by people all over the world because of the unique flavor. Esters of short-chain fatty acids are renowned for their contribution to the flavor of different fermented foods. In these foods, esters are produced in a diverse proportion because of microbial activities. 1,2 It is often needed to add esters as flavor additives to maintain and enhance the flavor or add a special flavor tone. 3 The growing demand for specific flavor has been a major scientific research area to produce esters on a large scale and in a safe and cost-proficient way. Natural sources such as fruits are the primary origin of esters. Esters can be extracted from these natural sources using various techniques such as fractional distillation, compound extraction using supercritical fluids, continuous liquid-liquid extraction, pervaporation, and adsorption. 4,5 Plants contain esters in a very low amount and also depend on the plant growth and climatic conditions. 6 Therefore, direct extraction of esters from natural sources is costly, time-consuming, and lower in yield, and the quality is not up to the mark. 7-9 But the extracted esters are marked as natural and can be used for food production. 10

Pathway-Based Metabolomics Analysis Reveals Biosynthesis of Key Flavor Compounds in Mango

“…Comparing mango cultivars with contrasting traits facilitated pathway interrogation. For example, the formation of 2-butenoic acid and ethyl butanoate contributing to fruity flavor of ‘Glenn’ starts from a precursor glucose . As shown in Figure A, the level of glucose was relatively higher in ‘Glenn’ compared to the other two cultivars that is aligned with our previous result .…”

“…Glucose converts to pyruvate, followed by acetyl-CoA, leading to the butanoate metabolism possibly through two different metabolic pathways (one via acetoacetyl-CoA and the other via 2-oxoglutarate) to form the resulting flavor compounds (2-butenoic acid and ethyl butanoate). Although the acetoacetyl-CoA route has been better known for this flavor formation (e.g., generation of ethyl butanoate in food), acetoacetyl-CoA was not detected in our mango samples, while the metabolites ( cis -aconitate, isocitrate, 2-oxoglutarate, and 2-hydroxyglutarate) of the 2-oxoglutarate route were favorably found in all samples, and these metabolites were increased in ‘Glenn’ coinciding with metabolic behaviors of their downstream flavor products (2-butenoic acid and ethyl butanoate) only detected in ‘Glenn’ (Figure A). The following correlation analysis confirmed the strong positive relationship between these precursors (glucose, pyruvate, cis -aconitate, isocitrate, 2-oxoglutarate, and 2-hydroxyglutarate) and products (2-butenoic acid and ethyl butanoate), supporting that the 2-oxoglutarate route may be one of the major metabolic pathways for the biosynthesis of fruity flavor in mango (Figure B).…”

Investigating the mechanism of the flavor formation in Sichuan sun vinegar based on flavor-orientation and metagenomics

“… Wang et al, 2022 ). Butanoic acid reacts with alcohol under the catalysis of esterase or lipase to form ethyl butyrate with banana and strawberry flavors ( Xu et al, 2020 ). Paraldehyde is an acid-catalyzed trimer of acetaldehyde ( Gunasekaran and Abraham, n.d. ).…”

Vibration mill‐assisted complex enzyme hydrolysis for flavoring of freeze‐dried sea cucumber powder

“…Furthermore, esters are typical volatile flavor components in food products, owing to their low odor threshold, contributing to the desirable fruitiness of meat (Wang et al, 2021). Two esters were detected in the sample: ethyl acetate exhibiting a fruity and wine‐like flavor (Watanabe et al, 2015) and ethyl butyrate exhibiting a fruity and sweet taste (Xu et al, 2020).…”