Maria Luzenira de Souza

Processamentos de amêndoa e torta de castanha-do-Brasil e farinha de mandioca: parâmetros de qualidade

Brazil nut (Bertholletia excelsa H.B.K.) and cassava (Manihot esculenta Crantz) are important raw materials, which constitute the basis of subsistence for those who live in the Amazon region. Due to a total lack of incentive for their use by the national food industry, this study aimed at processing Brazil nuts to obtain the nuts and the meal and at processing cassava to obtain the flour, studying the quality parameters which could justify and encourage their use. The absence of aflatoxin in both the nuts and meal indicated the high quality of the Brazil nuts with respect to food safety. The presence of a selenium content of 2.04mg/Kg in the nut and 7.13mg/Kg in the meal, a food fiber content of 8.02% in the nut, 15.72% in the meal and 5.68% in the flour, a protein content of 40.23% in the meal and carbohydrate content of 79.33% in the flour allowed for the characterization of products based on the nut as high protein, rich in selenium and fiber and of the cassava as rich in carbohydrate and fiber. The protein of the nut is complete and rich in sulfur amino acids and contains all the essential amino acids, some with values greater than and others equal to, the FAO standards. Due to these contents of amino acids, selenium and fiber, the consumption of the Brazil nut and derivatives should be encouraged due to their relevant functions with respect to human health.

Variabilidade físico-química da farinha de mandioca

The goal of this work was to evaluate the physicochemical variability of the cassava flour, sold in the city of Cruzeiro do Sul - in the state of AC (Brazil), by multivaried analysis. The following contents of eighteen different cassava flours were analyzed: moisture, ashes, lipids, protein, fiber, carbohydrates, acidity, and pH. Grouping multivaried analysis according to the Tocher method allowed the establishment of five groups of flours. The groups IV and V were considered high quality groups. The first one due to the lower ashes and higher protein contents; and the second due to the lower moisture and higher carbohydrates contents. The multivaried analysis techniques presented good responses to identify most heterogeneous flours. The physicochemical variability seen in the five different groups probably indicates different production processes.

Extrusão de misturas de castanha do Brasil com mandioca

Considering that Brazil nut presents high nutritional potential, low consumption in Brazil, low added-value and is an organic product; that cassava has high productivity and low cost; and that the technology of thermoplastic extrusion presents wide applicability and considerable advantages, the objective of this work was to use these three variables, formulating Brazil nut and cassava flour mixtures and processing them by extrusion, with the aim of obtaining ready-to-eat extruded products containing high levels of vegetable protein. Semi-defatted Brazil nut cake and cassava flour were used to formulate the mixtures for extrusion. A complete factorial central composite design (23) with 3 independent variables, and the response surface methodology were used to evaluate the results of the proximate composition and caloric value, according to the variations in the quantity of nut, moisture content and temperature. The results indicate that the mixtures with higher Brazil nut levels present higher levels of protein, fat and ash, while the mixtures with less Brazil nut present higher levels of carbohydrate. The average regression coefficients of the statistical model for the responses are: moisture 7.40; carbohydrate 51.09; protein 15.34; fat 11.77; total fibre 9.92 and kcal 371.65. The trials with lower quantities of Brazil nut and higher quantities of flour are more expanded and of a lighter colour, while those with more Brazil nut do not expand and are greyish in colour. It is concluded that the addition of Brazil nut to cassava flour results in a mixture that could be submitted to extrusion, producing an extruded product that could serve as a ready-to-eat source of vegetable protein, and attend the demands of consumers who do not consume proteins of animal origin.

Otimização do processo de extrusão termoplástica da mistura castanha do Brasil com farinha de mandioca

The objective of this work was to optimize the conditions of processing mixtures of Brazil nut with cassava flour through thermoplastic extrusion as a function of acceptability. A 23 full factorial design was used for the production of the extrudates and the evaluation of the products was according to acceptability responses. An affective hedonic scale of 9 points was applied to evaluate global acceptability and a 5-point scale was used to evaluate purchase intention. The results of the response surface methodology indicated that increases in Brazil nut percentage, temperature and moisture increased global acceptability and purchase intention of the product, with an optimized processing region in the following conditions: temperature between 120 and 160 °C, Brazil nut percentage between 48 and 80% and moisture between 20 and 25%. If Brazil nut percentage, temperature and moisture of the mixture were too high or too low, global acceptability and purchase intention decreased. The highest acceptance and purchase intention in this study were found for the central points and indicate the validity of the model.

Alternative covering in the shelf life conservation of yellow passion fruit produced in organic system

The present work had the objective to evaluate different substances: carnaubas wax, latex rubber tree, solution of calcium chloride and cassava starch in the shelf life of the yellow passion fruit stored under temperature atmosphere. Fruits selected, washed and sanitized with chlorinated water in 150 mg L-1, were submitted by the following treatment: 1 - control, washed and sanitized; 2 - immerse in carnauba´s wax (Fruit Wax); 3 - immerse in rubber tree latex, diluted in proportion of 1:3 (v/v); 4 - solution of calcium chloride in 1%; 5 - cassava starch in 2%. The experimental design was completely randomized in split-plot arrangement. The plot corresponded to the storage period (0, 3, 6, 9, 12 and 15 days) and the split-plot by the treatments, with 3 repetitions of 4 fruits each. The fresh weight of the fruit, fresh weight of the pulp, titratable acidity (TA), soluble solids (SS), ratio SS/TA and ascorbic acid of the yellow passion fruit was not affected by the coating with Fruit Wax, rubber tree latex, calcium chloride and cassava starch. The rubber tree latex, similar to the product commercialized as carnaubas wax was the most efficient coating, reducing the mass loss and the shriveling index and increasing in 4 and 3 days, respectively the shelf life of the fruits.

In natura açaí beverage: quality, pasteurization and acidification

O objetivo deste trabalho foi avaliar as caracteristicas fisicas, fisico-quimicas, quimicas e microbiologicas da bebida de acai (Euterpe precatoria Mart.) in natura, processada e comercializada em Rio Branco-Acre, submete-la a tratamentos de acidificacao e pasteurizacao e avaliar seus efeitos. Frutos de acai foram processados para obtencao da bebida, conforme geralmente consumida. Uma amostra de 25 litros foi coletada de uma unidade processadora, no mercado municipal de Rio Branco, transportada ao laboratorio da Unidade de Tecnologia de Alimentos da Universidade Federal do Acre para montagem de experimentos em delineamento inteiramente casualizado. Na bebida in natura e apos tratamentos realizou-se as analises de solidos totais, pH, acidez total titulavel, proteinas, lipidios, bolores e leveduras, coliformes totais e termotolerantes a 45 oC. Os resultados da ANOVA mostraram, exceto lipidios, diferenca (p < 0,01) nos parâmetros. A bebida de acai in natura apresenta elevada contaminacao por coliformes totais e termotolerantes a 45 oC, bolores e leveduras, estando em condicoes higienico-sanitaria insatisfatoria e insegura ao consumo. A pasteurizacao foi eficaz na reducao da microbiota da bebida, reduziu a contaminacao para nivel aceitavel, conforme a legislacao, garantindo qualidade e seguranca alimentar. O tratamento acidificado reduziu parcialmente a microbiota. A bebida e classificada como acai fino ou tipo C.

Physicochemical composition, color and sensory acceptance of low-fat cupuaçu and açaí nectar: characterization and changes during storage

This study aimed to evaluate the physicochemical composition, color and sensory acceptance of low-fat acai and cupuacu nectar, as well as changes in these parameters during storage. Nectars were prepared with acai pulp previously defatted by centrifugation on a pilot scale. The study consisted of two steps. In the first step, the physicochemical characteristics, instrumental color, and sensory acceptance of the nectar prepared with low-fat acai pulp were evaluated and compared with those of nectar prepared with full-fat acai pulp. In the second step, titratable acidity, pH, soluble solids, anthocyanin content, instrumental color, and sensory acceptance of the low-fat acai and cupuacu nectar were evaluated for 6 months of storage at 25°C in the absence of light. The use of low-fat acai pulp resulted in nectars with good overall acceptance, but with lower scores for color acceptance than those of the full-fat nectar. The low-fat nectar remained stable with respect to acidity, pH, and soluble solid content during storage for up to 180 days. However, there was degradation of anthocyanins, which had a negative impact on the product color and sensory acceptance over time. Under the conditions evaluated, the estimated product shelf life is up to 120 days.

Maturação e determinação do ponto de colheita de frutos de envira-caju

O presente trabalho objetivou identificar o ponto de colheita, os indices de maturacao e a qualidade dos frutos da envireira-caju (Onychopetalum periquino). Os frutos foram colhidos em cinco estadios de maturacao (1-verde; 2-verde-laranja; 3-laranja; 4-laranja-vinho, e 5-vinho), sendo o estadio 5 colhido ja amadurecido na planta e usado como padrao na determinacao do ponto de colheita e do indice de qualidade do fruto. Os frutos colhidos foram armazenados a 26 ± 3 oC e 85-90% de UR. O delineamento experimental foi o inteiramente casualizado, em esquema de parcela subdividida no tempo com tratamento adicional, com quatro repeticoes de tres frutos cada. As parcelas compreenderam os estadios de maturacao na colheita, e as subparcelas, a maturacao no dia da analise (0 dia para todos os estadios, 4 dias para os estadios 1 e 2, e 2 dias para os estadios 3 e 4). A interacao entre o ponto de colheita e o armazenamento afetou significativamente todas as variaveis analisadas, exceto o rendimento de polpa. Os frutos colhidos no estadio verde-laranja atingiram indices de qualidade equivalente aos frutos amadurecidos na planta, apos o amadurecimento. O ponto de colheita dos frutos corresponde a cor verde-laranja da casca, contendo 0,14% de acidez total titulavel (AT); 8,62% de solidos soluveis (SS); 64,17 de SS/AT; 60,55 g de peso medio, e 60,37% de rendimento de polpa, constituindo indices confiaveis do ponto de colheita.