Effect of Bentonite Fining on Proteins and Phenolic Composition of Chardonnay and Sauvignon Blanc Wines

Abstract

Bentonite fining is widely used to remove excess proteins in white wine prior to bottling in order to prevent protein haze formation. However, bentonite fining could also remove beneficial compounds in wine, e.g. phenolic compounds that contribute to sensory properties of wine. In this study, impact of bentonite fining on the phenolic composition of Chardonnay and Sauvignon Blanc wines has been investigated using four different bentonites: pluxcompact (PCT, Ca bentonite); bentolit (BTL, Na-Ca bentonite); pluxbenton (PBN, Na bentonite); and sperimentale (SPM, Ca-Na bentonite). Different bentonites showed similar efficiencies in removing haze-related proteins and resulted in significant decrease in total phenolic concentration. Impact on phenolic composition varied depending on the type of bentonite. In this study, fining with Ca-Na bentonite (SPM) resulted in the lowest concentrations of caftaric acid and flavanols, particularly epicatechin gallate, gallocatechin, catechin and epicatechin, which could lead to reduced mouthfeel of the resultant wine. Results presented in this study provided additional information for winemakers to choose appropriate bentonite to remove proteins with a minimal effect on reduction of phenolic compounds.

DCMC as a Promising Alternative to Bentonite in White Wine Stabilization. Impact on Protein Stability and Wine Aromatic Fraction

“…As described before [ 27 ], bentonite fining in wines always resulted in a significant decrease in total phenolic concentration. In contrast, the DCMC treatment had little influence on the wine phenolic content and for any dose tested, it only removed a smaller fraction of the phenolic compounds ( Figure 4 ).…”

Effects of Saignée and Bentonite Treatment on Phenolic Compounds of Marquette Red Wines

“…The study of Balík et al [ 32 ] showed that Saint Laurent red wines treated with 0.25 g/L or 1 g/L of bentonite led to a decrease in (+)-catechin and (−)-epicatechin content. The contradictory data might be due to the type of bentonite (e.g., sodium or calcium) used in the studies, which impacted the content of flavanols in treated wines differently [ 33 ].…”

Advances in White Wine Protein Stabilization Technologies

“…Typical bentonites are sodium bentonite, sodium-activated bentonite, and NaCacombined bentonite, which can remove a significant amount of total proteins [25]. The bentonite doses necessary to obtain stable wines can change depending on the type of wine, the type of bentonite, and the time of addition [24,26,45]. The bentonite dosage (after fermentation) was found to be between 2-3 g/L for Chardonnay, Pinot gris, Malvazija istarska, and Silvaner white wines [24][25][26].…”

“…In recent years, various commercial bentonites have been developed that differ in their relative amounts of Al 2 O 3 , SiO 2 , Na 2 O, K 2 O, CaO, MgO, Fe 2 O 3 , TiO 2 , MnO, and P 2 O 5 , although their exact compositions are not disclosed. These commercial bentonites can form either more compact or more fluffy bentonite lees (to reduce wine lees losses), may vary their capacity to remove PR-proteins and phenolic compounds, or adsorb additional compounds (besides proteins) [26,45]. Jaeckels et al [25] have demonstrated that bentonites might not remove a significant part of the glycosylated proteins above 70 kDa and showed that unremoved TLPs isoforms have a hydrophobic surface.…”