In this study we investigated the possibility of usingCandida zemplinina, as a partner ofSaccharomyces cerevisiae, in mixed fermentations of must with a high sugar content, in order to reduce its acetic acid production. Thirty-fiveC. zemplininastrains, which were isolated from different geographic regions, were molecularly characterized, and their fermentation performances were determined. Five genetically different strains were selected for mixed fermentations withS. cerevisiae. Two types of inoculation were carried out: coinoculation and sequential inoculation. A balance between the two species was generally observed for the first 6 days, after which the levels ofC. zemplininastarted to decrease. Relevant differences were observed concerning the consumption of sugars, the ethanol and glycerol content, and acetic acid production, depending on which strain was used and which type of inoculation was performed. Sequential inoculation led to the reduction of about half of the acetic acid content compared to the pureS. cerevisiaefermentation, but the ethanol and glycerol amounts were also low. A coinoculation with selected combinations ofS. cerevisiaeandC. zemplininaresulted in a decrease of ∼0.3 g of acetic acid/liter, while maintaining high ethanol and glycerol levels. This study demonstrates that mixedS. cerevisiaeandC. zemplininafermentation could be applied in sweet wine fermentation to reduce the production of acetic acid, connected to theS. cerevisiaeosmotic stress response.

Texture analysis is a well-established analytical technique in the food industry for evaluating the mechanical and physical characteristics of both raw ingredients and finished products. Instrumental mechanical properties of table grapes, acquired using universal testing machines equipped with specific probes, may be of interest in the viticulture and postharvest sectors to recognize the potential of each variety and help satisfy market requirements. The measured parameters are related to some sensory properties and, therefore, indirectly to consumer acceptability of the product. As texture analysis is a rapid and low-cost analytical technique, it can also be favorably applied in enology as a routine tool for monitoring winegrape quality. Among the different mechanical parameters measurable, berry skin thickness and hardness are indices that reflect anthocyanin extractability and dehydration kinetics with adequate reliability. This review collects the most recent research results from grape texture studies, emphasizes the potentiality and limits of this analytical technique when applied to grape studies, and highlights trends that require further understanding.