Silvio de Jesus Freitas

Avaliação sensorial dos frutos de cultivares de abacaxi para consumo in natura

The pineapple orchards in Brazil often presents losses of plants and fruits caused by fusariosis, because the current cultivars are susceptive to that disease. New resistant cultivars have been available. However, there are no records about their sensory evaluations by consumers. The objective of this work was to evaluate the sensory acceptability of two new cultivars resistant to Fusarium, Vitoria and EC-93, by comparing them with other ones already established in the fresh fruits market, Perola and Gold. The fruits were evaluated by 52 consumers using 9-points hedonic scale for aroma, flavor, texture, global impression, appearance of the slice, appearance of the fruit, using the right scale for ideal acidity and sweetness and using 5-points scale for purchase intention. It was also evaluated SS, ATTN and SS/AT. The cultivar Gold had the highest means of acceptance for most of the parameters evaluated, whereas the cv CS-93, the lowest. Except for the attribute appearance of slice, the Vitoria cultivar did not differ from the most accepted cultivars in the evaluated parameters. The fruits differed significantly in the TSS, between 12.0 and 16.0 ° Brix, TA between 0.52 and 0.81% citric acid and ratio between 19.12 and 28.46. Among the cultivars resistant to Fusarium, the results suggest a low potential market for the EC-93 and a higher one for Vitoria.

Crescimento inicial e teor nutricional do maracujazeiro amarelo submetido à adubação com diferentes fontes nitrogenadas

O trabalho teve como objetivo avaliar a influencia de diferentes fontes nitrogenadas sobre o crescimento inicial e o teor de nutrientes em folhas do maracujazeiro-amarelo. Para isto, foi instalado um experimento em DBC (delineamento em blocos casualizados), com quatro repeticoes em fatorial 4X5, sendo quatro fontes de nitrogenio (esterco bovino, esterco bovino + sulfato de amonio, esterco bovino + nitrato de amonio e esterco bovino + ureia) e cinco epocas de coleta de plantas (66; 82; 98; 111 e 127 dias apos a semeadura). As plantas foram conduzidas em vasos de 30 dm3 e em condicoes de casa de vegetacao. Com os resultados obtidos, foi possivel concluir que o tratamento contendo apenas esterco bovino apresentou menor numero de folhas por planta, menor area foliar, menor massa seca da parte aerea, menores valores de indice SPAD e os menores teores de N e Mg, quando comparado com os demais tratamentos. Para massa seca de raiz, as plantas submetidas ao tratamento com apenas esterco bovino apresentaram resultados superiores.

Avaliação da qualidade de frutos de quatro genótipos de abacaxi para consumo in natura

Brazilian pineapple cultivation has been damaged by the presence of Fusarium, due to the susceptibility of the main cultivars planted in this country to this fungus. Genetic improvement program has been searching new alternatives for pineapple producers with the development of new cultivars resistant to Fusarium. The main purpose of this study was to compare qualitative attributes of two cultivars resistant to Fusarium with two traditional cultivars of pineapple in natura. We used fruits with two genotypes resistant to Fusarium (cv. Vitoria and hybrid EC-93) and two susceptible commercial cultivars (Perola and Gold), so we evaluated quality characteristics like fruit mass, crown, pulp and central cylinder, diameters of the fruit and the central cylinder, fruit length, firmness, pH, titratable acidity (TA), soluble solids content (SS), SS/ TA ratio, vitamin C and color parameters L, a, b hue angle (oh) of pulp. The results showed that cv. Vitoria, white pulped, presented fruit with physical characteristics similar to that of cv. Perola, however, it had lower central cylinder, higher soluble solids content and higher acidity, resulting in SS/TA ratio lower. The peel of fruits cv. Vitoria had better mechanical resistance to the fruit of cv. Perola. The hybrid EC-93 had rates of fruit quality lower than those observed for cvs. Gold, Vitoria and Perola. The cv. Gold had the highest fruit weight (1.30 kg) and did not differ from cv. Vitoria (1.14 kg).

Ambientes de enraizamento para goiabeiras propagadas por estaquia ou miniestaquia

The goal of this study was to evaluate highmoisture saturation environments for rootingcuttings from guava. The experiment was carriedout in randomized complete block design infactorial scheme composed by guava tree cultivars(Paluma and Cortibel 6), types of cuttings(softwood cuttings and minicuttings), androoting environments (conventional chamberwith intermittent nebulization and minichambers constituted of plastic containers). Fourrepetitions were used and the experimental plotswere composed by ten softwood cuttings or minicuttings.Rooting of ‘Paluma’ ranged between77.5 and 97.5 % and of ‘Cortibel 6’ between2.5 and 57.5%, depending on the environmentand the propagation technique.

Effect of Growth Regulators in Production and Rooting of Coffea arabica L. Minicuttings

The plants of C. arabica do not naturally produce a large number of orthotropic sprouts, hindering clonal multiplication by cutting, which would be the simplest technique with a lower cost of production compared to other methods of vegetative propagation. An alternative form, used successfully in the propagation of eucalyptus, is propagation by minicutting, which consists of pruning the shoot apex of the plant, forming the ministumps, which in variable time interval emits the shoots that will be used to make minicutting. In C. arabica plants the number of shoots can be increased with the application of growth regulators and fertilizers. So, the purpose of this work was to verify the effect of growth regulators and foliar fertilizers on the emission and development of orthotropic shoots of C. arabica. The experiment was installed in a randomized complete block design, with ten treatments composed by growth regulators and fertilizers: T1 (Control); T2 (Stimulate + Sturdy + Enervig); T3 (Stimulate + Vitakelp + Biozyme); T4 (Tiba + Sturdy + Enervig); T5 (Tiba + Vitakelp + Biozyme); T6 (Brs + Sturdy + Enervig) T7 (Brs + Vitakelp + Biozyme); T8 (Stimulate); T9 (TIBA); T10 (Brs-Brassinoesteroid), each plot consisting of two plants. Biometric and physiological parameters were evaluated for the ministumps, as well as the biometric parameters of the shoots and plant survival. The results showed that there was no influence of the treatments on the biometric parameters of the ministumps. A greater number of orthotopic sprouts were obtained in treatments with the TIBA growth regulator, as well as a greater plant survival of the minicuttings, after 25 days of transplanting in a greenhouse. It was concluded that TIBA treatments influenced the production and quality of clonal minicuttings of C. arabica.

ALTERAÇOES ESTRUTURAIS EM MANDIOCAS PRODUZIDAS COM DIFERENTES CONDIÇÕES DE COZIMENTO

RESUMO Durante o cozimento de alimentos ricos em carboidratos, como e o caso da mandioca, ocorrem alteracoes estruturais, provocadas pela pen etracao de agua nos tecidos, que rompem as ligacoes entre cadeias dos carboidratos, criando camadas de hidratacao das moleculas separadas. Essas alteracoes sao provocada s pela gelatinizacao do amido, que acontece entre 45 e 80 oC. Este trabalho estudou ef eito do cozimento, com imersao em agua, em fatias de mandioca e analisou as alteracoe s provocadas nas diferentes condicoes de temperatura (40 a 100 oC) e tempo (2 a 10 minutos), determinando a melhor condicao para posterior secagem. Os resultad os mostraram que tanto a variavel tempo como a variavel temperatura influenciaram a umidade e a absorcao de agua das amostras apos o cozimento. A utilizacao de 70 °C po r 6 minutos no cozimento pode ser considerada como a condicao mais apropriada para posterior processamento como secagem, pois nesta as amostras apresentaram cozimento suficiente evidenciado pela formacao de gel superficial e nao apresentaram queb ra ou fissuras nas fatias.

SECAGEM COM MICRO-ONDAS DE “SNACKS” DE MANDIOCA UTILIZANDO O COZIMENTO COMO PRÉ-TRATAMENTO

RESUMO A mandioca e fonte de carboidratos e possui em media 65% de umidade, por isso, apresenta alta perecibilidade pos-colheita. A secagem e um metodo de conservacao de alimentos e a aplicacao de micro-ondas pode reduzir o tempo de secagem quando comparado com o metodo convencional de secagem com ar quente. A utilizacao de pretratamentos, como o cozimento, pode interferir no processo e gerar um produto final com melhores caracteristicas sensoriais e mais proximo do desejado pelo consumidor. Este trabalho avaliou o efeito de diferentes condicoes de temperatura (40 a 100 °C) e tempo de cozimento (2 a 10 min) em agua na cinetica de secagem de “snacks” de mandioca com ar quente combinado com micro-ondas (60 °C e 2,5 W/g). Os resultados indicaram que a temperatura de cozimento, e consequentes alteracoes estruturais promovidas nas raizes, apresentou efeito significativo na umidade e atividade de agua do produto seco, ou seja, quanto mais elevada a temperatura, maior foi a umidade e atividade de agua final. O processo de gelatinizacao do amido e provavelmente o fator dominante no decrescimo da velocidade de secagem dos produtos, principalmente quando cozidos em maiores temperaturas.

Ácidos húmicos e brassinosteroide no crescimento e estado nutricional de rebentos de coroas de abacaxi

Resumen pt: O proposito deste estudo foi avaliar o efeito da aplicacao de brassinosteroide e acidos humicos no crescimento e estado nutricional de rebentos oriundos ...