Replacement of SO2 with an Unripe Grape Extract and Chitosan during Oak Aging: Case Study of a Sangiovese Wine

Abstract

The aim of this study was to evaluate the chemical, microbiological and sensory characteristics of a Sangiovese wine aged in barrique with the addition of an unripe grape extract (UGE) as an alternative to sulfur dioxide. Three samples were considered: control wine (TQ) with free SO2 of approximately 15 mg/L; sample A with chitosan (100 mg/L) and UGE (200 mg/L); and sample B with UGE (400 mg/L). The results achieved in this work demonstrated that the UGE, either alone or in combination with chitosan, was able to maintain the color characteristics of the Sangiovese wine and its sensory quality. Moreover, the addition of UGE contributed to an early and better stabilization of the color through the formation of polymeric pigments. The microbiological stabilization was comparable to SO2 when UGE was used at 200 mg/L in combination with chitosan. The market survey conducted in the present study confirmed how the use of UGE as an alternative to sulfitation was positively accepted by consumers, who are increasingly attentive not only to the quality of the wines they select but also to the sustainability of the production processes from which they derive and to the fact that they are not harmful to human health.

Mechanisms of the initial stage of non‐enzymatic oxidation of wine: A mini review

“…A recent study has shown that the use of unripe grape extract and chitosan in Sangiovese wine can provide comparable protection against SO 2 . However, more experiments should be carried out in white wines, which are more susceptible to oxidation (Fia et al., 2023).…”

Evaluation of the Bio-Protective Effect of Native Candida Yeasts on Sauvignon Blanc Wines

“…Sulfur dioxide (SO 2 ) has played a key role in the wine industry due to its antimicrobial, antioxidant, and antioxidase properties, inhibiting the development of spoilage microorganisms including yeasts, lactic acid bacteria (LAB), and acetic acid bacteria (AAB) [1]; keeping the wine from browning after reacting with hydrogen peroxide [2]; and reducing wine quinones to their phenolic form [3]. However, recent decades have seen concerns raised related to its use in foods due to possible pseudo-allergic reactions associated with its consumption, including dermatitis, rashes, anaphylaxis, and even abdominal pain [4], which has led to limitations on its use in winemaking.…”