Aline Alberti

Apple wine processing with different nitrogen contents

The aim of this work was to evaluate the nitrogen content in different varieties of apple musts and to study the effect of different nitrogen concentrations in apple wine fermentation. The average total nitrogen content in 51 different apples juices was 155.81 mg/L, with 86.28 % of the values above 100 mg/L. The apple must with 59.0, 122.0 and 163.0 mg/L of total nitrogen content showed the maximum population of 2.05x 107; 4.42 x 107 and 8.66 x 107 cell/mL, respectively. Therefore, the maximum fermentation rates were dependent on the initial nitrogen level, corresponding to 1.4, 5.1 and 9.2 g/L.day, respectively. The nitrogen content in the apple musts was an important factor of growth and fermentation velocity.

Distribution of phenolic compounds and antioxidant capacity in apples tissues during ripening

The effect of variety and ripening stage on the distribution of phenolic compounds and in vitro antioxidant capacity of Gala, Fuji Suprema and Eva apples were evaluated. Hydroxycinnamic acids, flavonoids, flavanols, flavonols, dihydrochalcones and antioxidant activity (FRAP and DPPH) were assessed in the epicarp, mesocarp and endocarp of three varieties at three ripening stages (unripe, ripe and senescent). The Fuji Suprema variety distinguished by its content of flavonols at senescent stage, while Eva variety distinguished by its content of dihydrochalcones (unripe stage) and anthocyanins (ripe stage). In general, phenolic acids and flavonoids decreased with ripening in the epicarp and endocarp. However, in the mesocarp, the effect of ripening was related with the apple variety. Hierarchical cluster analysis confirmed the influence of ripening in the apple tissue. The evolution of these compounds during ripening occurred irregularly and it was influenced by the variety.

INFLUÊNCIA DA CEPA DE Saccharomyces cerevisiae NA CINÉTICA DE FERMENTAÇÃO DO VINHO DE MAÇÃ

O produto da fermentacao alcoolica do suco de maca constitui a base para a elaboracao da sidra, definida como uma bebida frisante de baixo grau alcoolico. A fermentacao pode ocorrer de forma natural por uma microbiota complexa ou pelo inoculo de leveduras comerciais, selecionadas e melhoradas para a fabricacao do vinho de uva. A avaliacao de diferentes cepas de leveduras comerciais na fermentacao da sidra torna-se importante a fim de que se possam definir parâmetros cineticos e de qualidade sensorial. Neste trabalho o objetivo foi avaliar o comportamento fermentativo de tres leveduras comerciais na elaboracao do vinho de maca. Foram utilizadas as cepas comerciais de Saccharomyces cerevisiae denominadas Uvaferm CK e Fermol®, e uma levedura de panificacao. Houve diferenca no crescimento maximo das tres cepas sendo que a de panificacao atingiu 5,13x107 ufc.mL-1 , enquanto que as demais, 3,52x107 e 2,65x107 ufc.mL-1 , para Uvaferm CK e Fermol ®, respectivamente. Houve diferenca tambem na velocidade de consumo de de acucares e na quantidade de nitrogenio consumida.

Chapter 39 – Characterizing Fruit Juices and Fermented Fruit Beverages Using Chemometrics Tools

Abstract In the 1990s there was a growth in the use of chemometric analysis. This was due to the advancement of computing which allowed the creation of software to perform mathematical and statistical calculations. Chemometrics is an important tool that is able to provide a large quantity of data (physicochemical, instrumental, microbiological, and sensorial) for the characterization or classification, determination of geographical origin, authenticity, traceability, and quality of juices and fermented fruit beverages. Different multivariate techniques can be used, among them the following stand out: unsupervised methods (principal component analysis, and hierarchical cluster analysis), supervised methods (linear discrimination analysis, k-nearest neighbor, soft independent modeling of class analogy, partial least-squares discriminant analysis, and artificial neural networks), and calibrations methods (multivariate linear regression, principal component regression, and partial least-squares). The use of chemometrics in the research on juices and fermented beverage fruit (wine, cider, and others) has impacted positively on scientific quality and it has generated interest in the industrial sector due to the potential applications.

Quality assessment of white mold‐ripened cheeses manufactured with different lactic cultures

BACKGROUND White mold-ripened cheeses were investigated with the objective of proposing a colorimetric method to monitor the surface growth of Penicillium candidum and to evaluate the influence of the mesophilic (homofermentative (QMO) and heterofermentative (QMLD)) and thermophilic (QT) starter cultures on the physicochemical composition and sensory description. RESULTS The whiteness index was effective in proving the appearance of superficial mycelium and the stability of white mold growth. The lactic cultures showed significant influence on most of the physicochemical analyses. The cheese made with thermophilic lactic culture had a 1 day gain in the growth of mycelium on the surface; nevertheless, the appearance of this product was potentially not acceptable for consumers. The heterofermentative mesophilic cheese had a better appearance and texture profile. However, the homofermentative mesophilic cheese showed aspects of fresh cheese and was acceptable for a wide range of consumers. CONCLUSION The whiteness index was efficient to monitor the surface growth of P. candidum. The highest proteolytic effect was found in the QMLD and QT cultures. However, the cheese elaborated with the QMLD culture showed the best sensory acceptance.

Optimization of bioethanol production from cheese whey and corn steep liquor using mixture desing

Fabiane Oliveira Farias fabi_of@yahoo.com.br Universidade Estadual de Ponta Grossa, Ponta Grossa, Paraná, Brasil.

Efeito da clarificação com gelatina no teor de compostos fenólicos e na atividade antioxidante de fermentados de maçãs

O objetivo deste trabalho foi avaliar o efeito da despectinização e da clarificação do mosto com gelatina sobre a cor, o teor de fenóis e a atividade antioxidante de fermentados de maçãs. Foram utilizados quatro mostos varietais, com os tratamentos: 1) despectinização do mosto antes do inóculo de levedura; 2) adição simultânea do agente despectinizante e da levedura ao mosto; e 3) mosto não submetido ao processo de despectinização. Estes tratamentos foram conduzidos na presença e na ausência de sulfito. O processo de despectinização não influenciou o tempo de fermentação alcoólica, porém houve efeito do fator varietal sobre o resultado. O processo de despectinização do mosto das cultivares Imperial Gala e Fuji Suprema diminuiu a concentração de compostos fenólicos; entretanto, não houve efeito do processo para as cultivares Belgolden e Granny Smith. O processo de clarificação com a gelatina aumentam as perdas de compostos fenólicos para os fermentados das cultivares Imperial Gala e Fuji. A clarificação com gelatina resultou em uma diminuição de 2 a 4 vezes da atividade antioxidante em todos os tratamentos.