Cláudia Kaehler Sautter

Comportamento pós-colheita de frutos de morangueiro após a aplicação pré-colheita de quitosana e acibenzolar-S-metil

ABSTRACT - The use of inductors of resistance in plants represents an alternative and a promising method to control fruit rots at postharvest. The experiment was carried out at Federal Technological University of Parana - Dois Vizinhos - Campus, during 2004 wit h theobjective to evaluate the induction of chitosan resistance and acibenzolar-S-methyl (ASM) on strawberry plants. The treatmentscompared the effect of chitosan (0.5; 1.0 and 2.0%) and ASM (0.0025%) in relation to control plants (distilled water only) and those withfungicides application. The chitosan treatment in all three evaluated concentrations, delayed the fruit maturation, increased the fleshfirmness and titratable acidity and decreased the mass loss. It was also observed reduction in the ethylene production and in thereduced sugars and increased the total polyphenol in strawberry fruits. The chitosan treatment in all three evaluated concentrationsinduced greater plant resistance to diseases with effect on the reduction of the fruit rots in the post harvest by Botrytis cindered.Although, chitosan treatment in the concentration of 2% caused damage to the fruits in the post harvest increased the respiration rateand the reduced sugar. The ASM had effect on the retention of the titratable acidity and acted efficiently on the rot reduction similar tothe treatment with fungicides. The application of chitosan and ASM pre-harvest did not interfere in the organoleptic quality of the fruitsin the post harvestIndex Terms: elicitor, ASM, chitosan, strawberry, quality, Botrytis cinerea.

Qualidade para processamento de clones de batata cultivados durante a primavera e outono no Rio Grande do Sul

A industrializacao da batata (Solanum tuberosum L.) tem sido limitada no Brasil, quase que exclusivamente, pela falta de materia-prima adequada. Alta qualidade do produto processado e dependente de altos teores de materia seca, que reduz a absorcao de oleo durante a fritura e confere crocância, e baixos teores de acucares redutores, que mantem a coloracao clara das fritas. O objetivo deste trabalho foi identificar clones de batata de alta qualidade para processamento a partir da avaliacao de tuberculos produzidos durante os cultivos de primavera de 2003 e outono de 2004 em Santa Maria, RS. O experimento foi conduzido em um fatorial (15 clones e duas epocas de cultivo) no delineamento de blocos ao acaso, com quatro repeticoes. Foram avaliados os clones Dakota Rose, SMINIAIpora, SMIJ461-1, SMIJ319-1, SMIJ456-4Y, SMID040-4RY, SMIE040-6RY, SMIC148-A, SMIF165-6RY, SMIH095-1, SMINIA90244-1, SMINIA793101-3, SMINIA95043-11, Macaca e Asterix nos cultivos de primavera de 2003 e outono de 2004 em Santa Maria, RS. As condicoes ambientais, durante o periodo de producao, influenciaram a qualidade pos-colheita dos tuberculos. Os clones SMIJ461-1, SMIJ319-1, SMIJ456-4Y, SMIC148-A, SMIDO40-4RY e SMIH095-1 foram os que apresentaram o melhor desempenho nas caracteristicas desejaveis para processamento, sendo superiores a Asterix, cultivada para consumo de mesa ou para processamento na forma de chips nas diferentes regioes produtoras de batata. Dentre esses clones, SMIDO40-4RY e SMIH095-1 foram os menos influenciados pelas diferencas de temperatura e insolacao tipicas das epocas de cultivo de outono e primavera no RS. Os clones SMIJ461-1 e SMIJ456-4Y apresentaram maior teor de materia seca e coloracao mais clara do chips no cultivo da primavera.

Determinación de algunos atributos de calidad de la variedad Fuji y sus mutantes al momento de cosecha

Many studies have shown that fruits and vegetables are not only source of energy and nutrients, but also source of important components as phytochemicals which help preventing cancer, cardiovascular and neurodegenerative diseases. The increasing apple production has a direct effect on the production of apple processed products. Therefore, the knowledge about healthy substances as polyphenols and anthocyanins is important in order to determine the potential use of apple fruits for processing industry. The objective of this work was to physicochemically characterize three apple cultivars, Fuji, Fuji Kiku, and Fuji Suprema. The characterization was based on pulp firmness, titrable acidity (TA), total soluble solids (TSS), iodine index, skin color, polyphenols, anthocyanins, reduced sugars, and vitamin C. According to the results, the Fuji Kiku cultivar had higher values of pulp firmness, AT, TSS and vitamin C. The Fuji Suprema cultivar showed more intense red color and higher levels of anthocyanins. There were no differences on polyphenols and reduced sugars.

Polifenóis totais e avaliação sensorial de suco de uvas Isabel tratadas com ultrassom

Grape juice in Brazil is a product widely consumed for their sensory and nutritional characteristics, however, treatments during processing can cause loss of phenolic compounds important in defining these characteristics. Ultrasound is cited as a possible elicitor of these compounds, since the mechanical stress caused by acoustic cavitation and microstreaming stimulates the plant defense responses that lead to synthesis of these substances. In this study, different power densities (53 and 113 W.cm-2) and exposure times (1, 5 and 10 minutes) of ultrasound were applied in Isabel grapes and its effect on the total polyphenols content and sensory aspect of the juices was evaluated. The ultrasound caused an increase of up to 83% in total polyphenols content, improving the sensory characteristics of juices, being chosen as preferred by the tasters.

Physicochemical, Antioxidant and Sensory Quality of Brazilian Blueberry Wine

Currently, Rio Grande do Sul state is the main producer of blueberry in Brazil. Practically all production is commercialized in fresh state and only a small portion is subject to processing. The blueberry wine making process is an alternative to expand the beverage industry and offers to the consumer a value-added product as well as a new market for Brazilian blueberry producers. The objectives of this study were to produce wines from blueberries and to evaluate the effect of deacidification (with calcium carbonate) and chaptalization (with glucose syrup or sucrose) on physicochemical characteristics, antioxidant content, and sensory parameters. Samples were analyzed for total soluble solids, pH, total titratable acidity, total sugar content, alcohol content, monomeric and total anthocyanin, total flavonols, total phenolic compounds and antioxidant activity by DPPH and FRAP methods. The use of calcium carbonate caused a reduction in total titratable acidity, while the use of glucose syrup resulted in wines with low alcohol content. The blueberries wine from Climax and Aliceblue cultivars had higher content of anthocyanin when produced with glucose syrup. The use of calcium carbonate and glucose syrup also provided wines more appreciated by tasters in relation to color. With regard to flavor, George and Aliceblue were the cultivars with lower preference under the control treatments (without carbonate and sugar). The presence of phenolic compounds may have provided a positive influence on wine flavor, once the more preferred wines presented the greater phenolic content.

PHYSICOCHEMICAL COMPOSITION AND SENSORY ANALYSIS OF WHOLE JUICE EXTRACTED FROM GRAPES IRRADIATED WITH ULTRAVIOLET C

Grape juice has been widely studied due to the presence of phenolic compounds and its beneficial effects on human health. Ultraviolet irradiation C (UV-C) can increase the content of phenolic compounds and anthocyanins and contribute to sensory acceptability. The aim of this study was to evaluate the effect of different doses of ultraviolet irradiation C (UV-C) on ‘Trebbiano’, ‘Niagara Branca’, ‘Isabel’ and ‘Cabernet Sauvignon’ grapes, as well as effect of the storage period. Juices were elaborated and evaluated for physicochemical analyses, and for the sensorial analysis in irradiated samples. In ‘Niagara Branca’ and ‘Trebbiano’ cultivars, storage and irradiation promoted few physicochemical alterations, and sensorially, irradiation reduced the intensity of flavor and color attributes. In juices from ‘Isabel’ and ‘Cabernet Sauvignon’ cultivars, the storage period led to the concentration of sugars and irradiation influenced physicochemical parameters and increased the intensity of aroma attribute at dose of 2 kJ m-2. Thus, UV-C irradiation contributes little for the improvement of white grape juices; however, it favors some sensory attributes in red grape juice, requiring further studies to elucidate the influence of UV-C irradiation on the phenolic and volatile composition of grape juice.

Storage of yerba maté in controlled atmosphere

The aim of this study was to evaluate the effect of controlled atmosphere in the change of color, chlorophyll degradation and phenolic compounds concentration in yerba mate thickly ground (“cancheada”) and thinly milled (“socada”). Yerba mate samples from the towns of Arvorezinha (RS - Brazil) and Sao Mateus do Sul (PR - Brazil) were stored in four levels of oxygen (1, 3, 6 and 20.9kPa of O2) and four levels of carbon dioxide (0, 3, 6 and 18kPa of CO2) and then were analyzed, after nine months of storage. According to the results, the O2 partial pressure reduction decreased the loss of green coloration, kept a higher content of chlorophylls and of total phenolic compounds. In relation to the different levels of CO2, a response as remarkable as O2 was not observed. The yerba mate that was thickly ground (“cancheada”) presented a better storage potential than the one thinly milled (“socada”) in the storage with O2 and with CO2. The 1kPa of O2 condition kept the yerba mate greener and with a higher content of chlorophylls and of total phenolic compounds after nine months of storage. The CO2 partial pressure kept the yerba mate coloration greener and with a higher content of chlorophylls and of total phenolic compounds, regardless of the level used, in the mate from both cultivation areas.

Acute Consumption of Bordo Grape Juice and Wine Improves Serum Antioxidant Status in Healthy Individuals and Inhibits Reactive Oxygen Species Production in Human Neuron-Like Cells

Few studies investigated the biological effects of American grape cultivars. We investigated the metabolic response after acute consumption of grape juice or wine from Bordo grapes (Vitis labrusca) in a placebo-controlled crossover study with fifteen healthy volunteers. Blood samples were collected 1 hour after the intake of 100 mL of water, juice, or wine to measure TBARS, ABTS, FRAP, glucose, and uric acid levels. To evaluate differences in cellular response, intracellular reactive species production (DCFH-DA) and metabolic mitochondrial viability (MTT) were assessed after exposure of human neuron-like cells (SH-SY5Y) to juice or wine. Glycemia was reduced after juice or wine consumption, whereas blood levels of uric acid were reduced after juice consumption but increased after wine consumption. Juice and wine consumption reduced plasma lipid peroxidation and increased plasma antioxidant capacity (ABTS and FRAP assays). Furthermore, juice inhibited H2O2-induced intracellular production of reactive species (RS) and increased the viability of SH-SY5Y cells. In contrast, wine (dealcoholized) exhibited a per se effect by inducing the production of RS and reducing cell viability. These results indicate a positive impact of acute consumption of Bordo juice and wine on human oxidative status, whereas only juice had protective effects against oxidative stress-induced cytotoxicity.

Caracterização, teor de polifenóis totais e atividade antioxidante em diferentes tipos de erva-mate (Ilex paraguariensis St. Hill.) para chimarrão

Considering the wide use of the yerba mate leaves, and the benefits derived from them, the present study aimed at evaluating the quality of four kinds of native yerba-mate of chimarrao-type: traditional; specimens with addition of 5 % and 10 % of sugar; and thick ground sample. The homogeneity aspect was analyzed in three batches of products, corresponding to different weeks of processing. Also, the physicochemical properties, the total polyphenols contents and the antioxidant activity were evaluated. The aqueous extracts of yerba mate were prepared at 85 °C kept in decoction in a closed system, for 10 and 30 minutes. The yerba mate with sugar addition showed lower levels of mineral material and crude fiber, when compared with the traditional and the thick ground types. The thick ground kind of yerba mate wrapped in laminated package showed the lowest values of water activity in relation to other types of herbs wrapped in paper package. The laminated package also contributed to the low oxygen absorption delaying the oxidation of chlorophyll, maintaining the green coloration of the product. The extracts prepared from the thick ground kind of yerba mate, and those exposed to the longer decoction showed higher levels of total polyphenols.