Banca de DEFESA: ISLAINE SANTOS SILVA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : ISLAINE SANTOS SILVA
DATA : 16/10/2020
HORA: 14:00
LOCAL: UFBA
TÍTULO:

The use of different fining agents in different steps of winemaking and its impacts on the quality of Chenin Blanc white wines

PALAVRAS-CHAVES:

HPLC-DAD-FD, Submiddle of the San Francisco Valley, clarification, bioactive compounds, tropical wines.

PÁGINAS: 100
GRANDE ÁREA: Ciências Agrárias
ÁREA: Ciência e Tecnologia de Alimentos
SUBÁREA: Tecnologia de Alimentos
ESPECIALIDADE: Tecnologia das Bebidas
RESUMO:

Clearness is one of the qualities most appreciated and required by the white wine consumer. The clarity and stability can be used through clarification, by the action of clarifying agents. Clarification consists of adding substances that induce flocculation and sedimentation in cloudy or colloidal instability wines, ensuring long-term clarity and preventing deposits during storage. However, this operation alters the composition of the wine, since removing substances phenolic, also influencing color characteristics, in addition to intervening in the aromatic profile of wine. A variety of protein clarifying agents of animal origin have been used worldwide to make white wines, however, with the advent of bovine spongiform encephalopathy in the 1980s and the allergenic nature of certain proteins, considerable interest has emerged in the replacement of these animal proteins and the alternative use of clarifying agents. In this sense, this study tested clarifying agents of animal, synthetic and mineral origins, relationships in different stages of winemaking, in order to evaluate their effects on the physical-chemical composition, the content of phenolic compounds, the antioxidant potential and the profile sensory effect of the white wine of the cultivar 'Chenin Blanc', with the intention of optimizing a clarification operation for the wine industry, by choosing the agents and the steps that should be due, more appropriate to the final product, as well as, evaluating the effectiveness of alternative agents to those of animal origin..Five treatments were tested: a control (without the use of clarifiers), T₁ - with the use of bentonite in debourbage (0.3 g L^-1) and in stabilization (0.4 g L^-1), T₂ - with bentonite in the stabilization (0.7 g L^-1), T₃ - with PVPP (0.05 g L^-1) and bentonite (0.1 g L^-1) in alcoholic fermentation (AF) and bentonite (0.6 g L^{- 1}) in stabilization and T₄ - with gelatin (2 mL L^-¹) and bentonite (0.1 g L^-1) in AF and bentonite (0.6 g L^-1) in stabilization. Physical analyzes, instrumental color analyzes, phenolic compounds by HPLC, antioxidant potential (DPPH, ABTS and FRAP), sensory profile (CATA) and acceptance test were performed. It was evident that the use of clarifying agents does not express a negative effect on the phenolic composition of wines, the antioxidant potential and sensory quality. The use of bentonite in the elimination and stabilization (T₁) of wines, expresses the greater preservation of the phenolic compounds present, especially the phenolic acids, flavonols and some flavan-3-ols such as (+) - catechin and procyanidin B1, responsible for the highest antioxidant potential.

MEMBROS DA BANCA:
Presidente - 225.961.678-08 - ALINE CAMARÃO TELLES BIASOTO - EMBRAPA
Interno - 4725209 - CAROLINA OLIVEIRA DE SOUZA
Externo à Instituição - FÁBIO LANER LENK - IFSP