Evaluating the Potential for Different Fabrics to Protect Grapes from Contamination by Smoke.

Vineyard smoke exposure can lead to the accumulation of free and glycosylated volatile phenols (VPs) in grapes, negatively affecting wine quality. Activated carbon fibre (ACF) cloth has proven effective in mitigating smoke contamination of grapes, but its commercial use is hindered by low tensile strength and light transmission. This study therefore compared the efficacy of different fabrics (polyester, polypropylene, cotton and viscose) to mitigate the smoke contamination of grapes (benchmarking against ACF cloth), alongside their physical properties (i.e., tensile strength and air permeability). Polyester and polypropylene provided limited protection, whereas grapes enclosed in cotton or viscose had VP profiles that were comparable to grapes enclosed in ACF cloth (i.e., VP concentrations ≤ 5.3 µg/kg). In a subsequent trial, ACF cloth prevented the uptake of >90% of smoke-derived VPs during ten successive smoke treatments, but after repeated smoke exposure, VP concentrations had increased in grapes enclosed in cotton and viscose, presumably due to saturation. Washing and drying restored the protection afforded by cotton and viscose but resulted in the disintegration of the ACF cloth. However, the application of a non-woven fabric to one or both sides of the ACF cloth improved tensile strength, without significantly compromising air permeability. These findings demonstrate the potential for fabric coverings to be used to mitigate the occurrence of smoke taint in the vineyard, with ACF affording superior protection.