The Application of Ultrasound and Enzymes Could Be Promising Tools for Recovering Polyphenols during the Aging on Lees Process in Red Winemaking

Abstract

The final concentration of phenolic compounds in wines is usually lower than what might be expected, given their concentration in grapes. This is in part due to the interactions between cell walls from grapes and yeast with phenolics during red winemaking. Most of these aggregates are insoluble and end up precipitating, forming part of the lees. The objective of this study is to determine the capacity of ultrasounds and/or enzymes treatments (β-glucanase and a pectolytic enzyme) to release the anthocyanins and tannins adsorbed in the lees. The ultrasound (US) applied for 120 min slightly favored the extraction of anthocyanins and doubled tannin extraction. Shorter sonication times did not show any positive effect. The combination of β-glucanase and pectolytic enzyme was always more effective in the liberation of anthocyanins (both no-acylated and acylated anthocyanins) and tannins than the enzymes acting separately. The combination of US (120 min), β-glucanase and pectolytic enzyme showed an additive effect, increasing the extraction of phenolic compounds with respect to the individual treatments and also releasing a large quantity of low molecular weight polysaccharides, compounds of enological importance. These results of this study could be of enological interest, facilitating and accelerating the aging on lees process, through the liberation of polysaccharides and the recovery of the phenolic compounds lost during vinification.

Grape Pulp Fiber as Possible Fining Agents for Red Wine

“…This could probably be due to the action of the enzyme that was used in the settling step of the vinification process (Enozym Lux, a mixture of pectin lyase and polygalacturonase). This enzyme has been shown, in previous studies, to have a high capacity to degrade cell wall pectins and produce a large quantity of soluble low molecular weight polysaccharides [ 11 , 12 , 41 ]. In the study by Bindon et al [ 9 ], they showed that the use of a pectinolytic enzyme was capable of solubilizing a high concentration of galacturonic acid, rhamnose, and arabinose, both in cell walls from the grape pulp and skin, this being indicative of the depectination that the cell walls have suffered after the enzymatic treatment.…”

Formation of chromatic indices of grape juice by cryomaceration before ultrasonic treatment

“…Experimental grape juice samples that were subjected to cryomaceration and ultrasound treatment had a shift in chromatic indices towards a pink tint. This may be caused by the degradation of anthocyanins, as a result of which they were able to chelate metal cations [5], and therefore a change in the color gradient from light straw to "blush", which is characterized by pink color, according to the international classi cation of rosé wines, was observed.…”

Ultrasound‐assisted production of alcoholic beverages: From fermentation and sterilization to extraction and aging

“…Recently, US technologies were studied in β‐glucanase (GLUC) and pectolytic (PEC) enzymes in red wine lees to observe their effects on the extraction yield of tannins and anthocyanins (Osete‐Alcaraz et al., 2021). Hence, a 280 W US bath was used at 40 kHz in 30, 60, and 120 min, where sonication times were denoted as US30', US60', and US120', respectively.…”