Determination of the Grape Invertase Content (Using PTA−ELISA) following Various Fining Treatments versus Changes in the Total Protein Content of Wine. Relationships with Wine Foamability

Abstract

Proteins have proven to play a major role in the stabilization of foam in Champagne wines despite their low concentration that ranges from 4 to 20 mg/L. The aim of this study was to evaluate the effect of fining on total protein and grape invertase contents of champenois base wines and their foaming properties. Data showed that fining and especially the use of bentonite at doses ranging from 10 to 50 g/hL leads to a significant decrease in the total protein content of wines together with that of the grape invertase content, with such a decrease being very detrimental to the foaming properties of the treated wines in terms of foam height (HM) and foam stability (HS). Only a slight decrease in the total protein content, in the grape invertase concentration, and in the foam quality of wines was observed when using casein (10 and 20 g/hL) or bentonite combined with casein (both at 20 g/hL). Our study thus clearly establishes the good correlation existing between the wine protein concentration and its foaming properties. A remarkable correlation was observed between the decrease in the grape invertase content and the total protein content of wines, following bentonite treatments, suggesting that the grape invertase (which represents at least 10-20% of the wine proteins) follows a similar behavior upon fining to other proteins of Champagne wines, despite the high molecular mass and the highly glycosylated structure of this particular protein. Moreover, the decrease in total protein and grape invertase contents of wine after fining with bentonite was found to be correlated with a decrease in the foaming properties of the corresponding wines (with respectively R(2) = 0.89 and 0.95).

Influence of Wine Chemical Compounds on the Foaming Properties of Sparkling Wines

“…This grape protein possesses a pI close to the pH of wine and a high hydrophobicity, potentially conferring good surface properties on this protein [51]. Significant decreases in the invertase content in base wines have been shown to correlate with decreases in foam height and foam stability [46]. Other grape proteins, such as thaumatin-like proteins and chinases, did not contribute alone to the formation and stabilization of foam; however, when synergistically acting with mannoproteins, foam height was found to be maximized [33].…”

“…Diverse studies have been published about the influence of stabilization treatments, either using clarifiers or filtrations, on the foam quality of wines [20,24,41,46,47,[71][72][73][74]. In all cases, the foams were negatively affected by these treatments, and this was directly correlated with a decrease in the protein concentration.…”

Impact of drought stress on concentration and composition of wine proteins in Riesling

“…Although the polysaccharides are always the dominating fraction, they are basically not haze active, maybe with the exception of calcium pectate [7]. Proteins are always found at much lower concentrations in wines [8][9][10][11]. However, proteins strongly affect the clarity and colloidal stability of wines.…”

Effect of non-protein factors on heat stability of Chilean Sauvignon Blanc wines

“…It is widely accepted that proteins belong to one of the most important compounds in white wines that affect quality by contributing to their sensorial and foam characteristics (Dambrouck et al, 2005;Cilindre et al, 2007). However, white wines without bentonite fining exhibit normally turbidity formation when exposed to increasing temperatures (30 to 80 °C) followed by storage at 4 °C (Mesquita et al, 2001).…”