Acácio Antonio Ferreira Zielinski

Classification of juices and fermented beverages made from unripe, ripe and senescent apples based on the aromatic profile using chemometrics

The aim of this study was to assess differences between apple juices and fermented apple beverages elaborated with fruits from different varieties and at different ripening stages in the aroma profile by using chemometrics. Ripening influenced the aroma composition of the apple juice and fermented apple. For all varieties, senescent fruits provided more aromatic fermented apple beverages. However, no significant difference was noticed in samples made of senescent or ripe fruits of the Lisgala variety. Regarding the juices, ripe Gala apple had the highest total aroma concentration. Ethanal was the major compound identified in all the samples, with values between 11.83mg/L (unripe Lisgala juice) and 81.05mg/L (ripe Gala juice). 3-Methyl-1-butanol was the major compound identified in the fermented juices. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied and classified the juices and fermented juices based on physicochemical and aroma profile, demonstrating their applicability as tools to monitor the quality of apple-based products.

Development and optimization of a HPLC-RI method for the determination of major sugars in apple juice and evaluation of the effect of the ripening stage

Abstract The sugars in apple juice prove its authenticity and its sensory and nutritional properties. The aim of this study was to develop and validate a simple analytical method using high performance liquid chromatography with refractive index detection (HPLC-RI) to determinate and quantify the sugars sucrose, D-glucose, D-fructose, and D-sorbitol polyol in apple juices, as well as to analyze the juices from the Fuji Suprema and Lis Gala cultivars at three ripening stages. The analytical performance parameters evaluated indicated that the method was specific for the compounds analyzed, and the linearity of the calibration curves of sugars showed high correlation coefficients (close to 1.0). The limits of detection and quantification are consistent with recommendations available in the literature for this type of matrix. Sample preparation is simple and generates small amount of residues. Over 70% of the sugars were determined in the juices of apples at the pre-ripe stage, with an increase during senescence. This method is applicable for the determination of sugars in juices and evaluation of apple ripening.

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.

DETECTION AND QUANTIFICATION OF PHYTOCHEMICAL MARKERS OF Ilex paraguariensis BY LIQUID CHROMATOGRAPHY

Ilex paraguariensis (yerba-mate) is used as a beverage, and its extract requires adequate quality control methods in order to guarantee quality and safe use. Strategies to develop and optimize a chromatographic method to quantify theobromine, caffeine, and chlorogenic acid in I. paraguariensis extracts were evaluated by applying a quality by design (QbD) model and ultra high-performance liquid chromatography (UHPLC). The presence of these three phytochemical markers in the extracts was evaluated using UHPLC-MS and was confirmed by the chromatographic bands in the total ion current traces (m/z of 181.1 [M+H]+, 195.0 [M+H]+, and 353.0 [M−H]−, respectively). The developed method was then transferred to a high-performance liquid chromatography (HPLC) platform, and the three phytochemical markers were used as external standards in the validation of a method for analyses of these compounds in extracts using a diode array detector (DAD). The validated method was applied to quantify the chlorogenic acid, caffeine, and theobromine in the samples. HPLC-DAD chromatographic fingerprinting was also used in a multivariate approach to process the entire data and to separate the I. paraguariensis extracts into two groups. The developed method is very useful for qualifying and quantifying I. paraguariensis extracts.

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.

COMPARACÃO DOS PRINCIPIOS TECNOLÓGICOS DO PROCESSAMENTO DE SUCO DE MAÇÃ AOS DOS DE PÊRA

A cultura de pereira apresenta potencial de expansao na Regiao Sul do Brasil podendo aproveitar parte da infraestrutura tecnologica e de armazenamento ja instalada para a cultura da macieira, desde a pesquisa de melhoramento genetico com tecnicas de manejo mais atualizadas e economicas. O pais, considerado um grande produtor de frutas, pode dentro de algum tempo suprir a demanda com peras de qualidade como aconteceu com a pomicultura nas ultimas tres decadas. O objetivo deste artigo trata da avaliacao das possibilidades de serem usados os caminhos tecnologicos da maca para a pera com tempo habil para que possa ser incrementada a sua producao e ao mesmo tempo possa ser planejado o seu processamento com produtos nobres. Raras unidades industriais sao vinculadas ao processamento de suco, porem safras com muita producao bem como os subprodutos desqualificados para o comercio no varejo faz com que se viabilize o processamento de produtos nobres, ate mesmo como base para outras bebidas inovadoras. Para tanto, amostra de peras comerciais sao descritas quanto as suas singularidades desde aspectos botânicos ate de acabamento de produtos, mantendo a maca como referencial cientifico e tecnologico e com isto se procura verificar se os equipamentos utilizados no processamento da maca sao adequados para a pera. Os rendimentos gravimetricos comparados do suco de pera e de maca foram uteis para indicar a afinidade de cada materia prima sendo que os resultados obtidos com a despolpadeira e pela tecnologia enzimatica foram os quantitativamente melhores enquanto o convencional apresentou o mais baixo.