Alternativas para diminuição da adstringência em vinho cabernet sauvignon da campanha gaúcha

Abstract

The work was made with wines made with Cabernet Sauvignon grapevines in the municipality of Dom Pedrito, RS. In Brazil this grapevine has great potential for the elaboration of red wines for ageing and also has a good adptability in the Campanha Gaúcha. Among the alternatives used to minimize the astringency that became noticeable after the wine was ready, the use of enological supplies was adopted in different dosages: minimum, medium and maximum in individual and joint quantities. Due to these circumstances, the objective of this work was to study the application of gum arabic and mannoproteins in an attempt to reduce astringency in the composition of wines Cabernet Sauvignon vintage 2015.The wine used in the different treatments was elaborated by means of long maceration, 12 days, and as a consequence, it had a high astringency. In total, there were 10 treatments without repetitions; the first treatment was the control (T1), without addition of inputs; the second treatment (T2), 50 mg/l gum arabic was added; the treatment third (T3) the dosage was 100 mg.L-1; the fourth treatment (T4) was added 150 mg.L-1 of gum arabic; the fifth treatment (T5) received the minimum dosage of mannoprotein (10 g.hl-1); the sixth treatment (T6) was added 20 g.hl-1 of mannoprotein; the seventh treatment (T7) 30g.hl-1 of mannoprotein was joined; the treatments tested with gum arabic and mannoprotein were: the eighth treatment (T8) with 50 mg.L-1 of gum arabic + 10g.hl-1 of mannoprotein; the nineth treatment (T9) with 100 mg.L-1 of gum arabic + 20 g.hl-1 of mannoprotein; and the last treatment (T10) with 150 mg.L-1 of gum arabic + 30 g.hl-1 of mannoprotein. At the beginning of 2016 the o oenological supplies were addedint different dosages in each of the treatments, after that, which wines were bottled and remained for 12 months until the sensorial and physico-chemical analyzes were performed. The different physico-chemical and sensory parameters analyzed in this work show that the use of mannoproteins in conjunction with gum arabic in minimum dosages (gum 50 mg.L-1 of gum arabic + 10g.hl-1), provide an improvement of the wines related to the decrease in astringency. The highlights were the sweetness / unctuousness, body / structure and quality in the mouth that obtained higher scores regarding the overall evaluation, being preferred among the evaluators. Nevertheless, by the protective colloid effect of gum arabica a positive highlight was obtained in the polyphenolic matrix of the wines, lower values corresponding to the HCL index and gelatin index.