Scielo RSS <![CDATA[Scientia Agropecuaria]]> http://dev.scielo.org.pe/rss.php?pid=2077-991720160002&lang=es vol. 7 num. 2 lang. es <![CDATA[SciELO Logo]]> http://dev.scielo.org.pe/img/en/fbpelogp.gif http://dev.scielo.org.pe <![CDATA[<strong>Yield performance of bushing snap bean genotypes in two environments</strong>]]> http://dev.scielo.org.pe/scielo.php?script=sci_arttext&pid=S2077-99172016000200001&lng=es&nrm=iso&tlng=es No estado do Paraná são escassas as informações sobre o desempenho produtivo de genótipos de feijão-vagem de crescimento determinado em ambientes distintos. Neste sentido, objetivou-se avaliar o desempenho produtivo de genótipos de feijão-vagem arbustivo em dois ambientes. O delineamento experimental foi o de blocos ao acaso, em esquema fatorial 3x2, sendo três genótipos (UEL 1, UEL 2 e Feltrin Vicenza Amarelo Baixo®) e dois ambientes (Tamarana e Londrina), com quatro repetições. Foram avaliados os seguintes parâmetros: dias para florescimento, número médio de vagens por planta, peso médio de vagens por planta e rendimento de vagens. Exceto para dias para florescimento, em que foram verificados efeitos isolados de genótipo e ambiente, constatou-se interação significativa entre genótipo x ambiente para os demais parâmetros. Para UEL 1, o número médio de vagens por planta foi superior em Londrina, com influência direta no rendimento de vagens. O componente peso médio de vagens por planta foi superior e determinante para o rendimento de vagens em Tamarana, para os genótipos UEL 2 e Feltrin. A interação genótipo x ambiente evidenciou respostas diferenciadas dos genótipos avaliados ao ambiente de produção em relação a número médio de vagens por planta, peso médio de vagens por planta e rendimento de vagens<hr/>In Parana state are little information about the yield performance of bushing snap bean genotypes in different environments. The study aimed to evaluate the performance of bush snap beans genotypes in two environments. The experimental design was randomized blocks, in 3x2 factorial design, with three genotypes (UEL 1, UEL 2 and Feltrin Vicenza Amarelo Baixo®) and two environments (Tamarana and Londrina, both in Parana state), with four replications. The following parameters were evaluated: days to flowering, average number of pods per plant, average weight of pods per plant and yield of pods. Except for days to flowering, in which isolated effects of genotype and environment were checked, it was found a significant interaction between genotype x environment for the other parameters. To UEL 1, the average number of pods per plant was higher in Londrina, with direct influence on the pods yield. The component average weight of pods per plant was higher and determiner the pods yield in Tamarana for the UEL 2 and Feltrin genotypes. The genotype x environment interaction showed different responses of genotypes evaluated to the environment in relation to numbers of pods per plant, weight of pods per plant and pods yield <![CDATA[<strong>Aspectos biológicos y control de un gracilláriido (Gracillariidae: Lepidóptera) en <i>Caesalpinia spinosa</i> (Mol.) Kuntze (1898), en Cajamarca, Perú</strong>]]> http://dev.scielo.org.pe/scielo.php?script=sci_arttext&pid=S2077-99172016000200002&lng=es&nrm=iso&tlng=es Se tuvo por objetivo determinar aspectos biológicos, identificar enemigos naturales, y establecer periodos oportunos de control de un gracillariido plaga de tara. Los aspectos biológicos y los enemigos naturales se evaluaron en campo y en laboratorio, los periodos oportunos de control se determinó por interacción hospedero-plaga. Los resultados, el huevo dura 7,8 días y mide 0,34x0,21mm; la larva presenta 4 instares y dura 35,7 días, variando de medidas entre 1o y 4o instar de 0,09 a 0,65 mm de diámetro de encéfalo; la pupa dura 14,3 días y mide 6,7mmx1,1mm; el adulto dura 7,5 días y mide 13,43 mm de expansión alar. Presenta enemigos naturales, familias Encyrtidae, Ichneumonidae, y géneros Chelonus sp., Chrysoperla sp., Hemerobius sp., Cicloneda sp., Hipodamia sp., y Zelus spp. Las mejores épocas de control ocurren cuando la fenología de la tara está entre R3.1 a R4 y R3.3 a R6<hr/>Determine biological target, identify natural enemies, and establish appropriate periods of controlling a pest gracillariid tare. The biological aspects and natural enemies in field and laboratory were evaluated, appropriate control periods was determined by host-pest interaction. The results, egg lasts 7.8 days and measured 0.34x0.21 mm; presents four instars larvae and lasts 35.7 days, ranging from measures between 1st and the 4th instar from 0.09 to 0.65 mm diameter brain; the pupa lasts 14.3 days and measured 6.7mmx1.1mm; adult takes 7.5 days and measured 13.43 mm wingspan. Presents natural enemies, family Encyrtidae, Ichneumonidae, and genres Chelonus sp., Chrysoperla sp., Hemerobius sp., Cicloneda sp., Hippodamia sp., and Zelus spp. The best times control occur when the phenology of the tara is between R3.1 to R3.3 and R4 to R6 <![CDATA[<strong>Phytochemical characterization of bioactive compounds on methanolic and ethanolic leaf extracts of <i>Myrciaria</i> sp</strong>]]> http://dev.scielo.org.pe/scielo.php?script=sci_arttext&pid=S2077-99172016000200003&lng=es&nrm=iso&tlng=es Among the native species of importance in Brazil, jabuticabeira (Myrciaria sp.) is a native fruit tree from several Brazilian regions. Few studies report the chemical constituents of the leaves and its pharmacological and nutraceutical properties. The aim of this study was to identify the phenolic compounds of the methanolic (MeOH) and ethanolic (EtOH) leaf extracts of Myrciaria sp. Phytochemical profile of the extracts was carried- out using High Performance Liquid Chromatography (HPLC) analysis. Antioxidant potential was evaluated by radical scavenging capacity with 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and total phenolics were determined with Folin-Ciocalteau reagent. A total of nine different compounds were identified in the free and bound phenolics extractions: 2,4 dihydroxybenzoic, vanillin, p-coumaric, ferulic, sinapinic, rutin, epicatechin, trans- caffeic and myricetin. The extracts demonstrated high radical scavenging capacity (MeOH: 1.83 and EtOH: 8.05 mg/mL) and high phenolic content (MeOH: 1.15; and EtOH: 1.04 mg/g dry matter). The wide variability of compounds revealed and the amount of peaks not identified, gives us a background of a potential plant matrix for further investigations in order to develop a nutraceutical agent <![CDATA[<strong>Cambios en la características físicas y químicas de granos de cacao (<i>Theobroma cacao</i>) fermentados con transferencia manual y semi-mecanizada, entre las cajas de fermentación</strong>]]> http://dev.scielo.org.pe/scielo.php?script=sci_arttext&pid=S2077-99172016000200004&lng=es&nrm=iso&tlng=es The aim of this study was to evaluate variation in the physical and chemical properties of fermented cocoa beans with cocoa beans transfer between wooden fermentation boxes manually (M) and semi-mechanized (SM) way. Mass temperature, moisture, pH, and total acidity of the cotyledon and pulp; the total polyphenol, anthocyanin, reducing sugar, theobromine, and caffeine content in fresh, fermented, and dried beans; and percentage of fermented beans and time required to move beans during fermentation were determined. The cocoa used grew in the Pachiza district of the San Martin region of Peru. Cocoa sampling was each 0, 48, 72, 96, 120, 144, and 168 h of fermentation. The cocoa mass temperature was highest with both removal systems after 96 h of fermentation. M cotyledon and pulp samples had the highest moisture content and titratable acidity, while cotyledon and pulp pH with both systems were statistically equal. In contrast, fermented beans had a higher polyphenol, anthocyanin, reducing sugar, theobromine, and caffeine content with SM. SM produced the greatest amount of fermentation (91.67%) and required the shortest amount of time to move beans (78.56 min). In conclusion, the system of fermentation of cocoa beans with SM was faster and produced fermented grains with high chemical quality <![CDATA[<b>Efecto de la sustitución parcial de la harina de trigo por harina de soya en las características tecnológicas y sensoriales de cupcakes destinados a niños en edad escolar</b>]]> http://dev.scielo.org.pe/scielo.php?script=sci_arttext&pid=S2077-99172016000200005&lng=es&nrm=iso&tlng=es El objetivo de esta investigación fue evaluar el efecto de la sustitución parcial de harina de trigo por harina de soya (HS) en las características tecnológicas y sensoriales de cupcakes, con la finalidad de desarrollar un alimento rico en proteínas para alumnos en edad escolar. Se sustituyó la harina de trigo común por HS en 4 porcentajes diferentes 5% (F1), 10% (F2), 15% (F3) y 20% (F4) y se comparó con una muestra control con 0% (F0) de HS. Las características tecnológicas evaluadas fueron: pérdida de peso, actividad de agua (Aw), color instrumental, volumen específico y texturometría de las muestras durante 12 días. Los resultados mostraron que la sustitución por HS mejora la firmeza de los cupcakes y ayuda a la retención de la humedad, una sustitución hasta F2 no presentó diferencia significativa con F0. Para la evaluación sensorial se aplicó un test con escala hedónica a 45 panelistas, se evaluaron 3 características sensoriales (color, sabor y textura) e intensión de compra. Los cupcakes con HS presentaron diferencias significativas en el color en relación con F0, los resultados indicaron que este ingrediente puede sustituir a la harina de trigo de la F0 hasta en un 10%, sin alterar significativamente su calidad sensorial. En cuanto a la intensión de compra, F2 obtuvo un puntaje de 4,20 ± 0,53 en una escala de 5 puntos, el cual no presenta diferencias significativas con F0.<hr/>The objective of this research was evaluate the effect of the partial substitution of wheat flour by soybean meal (HS) in the technological and sensory characteristics of cupcakes, in order to develop a high-protein food for school-age students. Common wheat flour was replaced with four different percentages of HS: 5% (F1), 10% (F2), 15% (F3) and 20% (F4), these were compared with a control sample with 0% (F0) of HS. The technological characteristics evaluated were weight loss, water activity (Aw), instrumental color, bulk and texturometria samples, for 12 days. The results showed that the substitution of HS improves firmness of cupcakes and helps moisture retention, a substitution until F2 was not significantly different from F0. A test to 45 panelists with a hedonic scale for sensory evaluation was used; three sensory characteristics (color, flavor and texture) and purchase intent were evaluated. The cupcakes with HS presented significant differences in color in relation to F0; the results indicated that this ingredient could replace wheat flour F0 up to 10%, without significantly altering its sensory quality. As for the intention to purchase, F2 obtained a score of 4.20 ± 0.53 on a scale of 5 points, which does not differ significantly from F0. <![CDATA[<b>Propiedades mecánicas de bandejas elaboradas con almidón de especies vegetales nativas y fibras de residuos agroindustriales</b>]]> http://dev.scielo.org.pe/scielo.php?script=sci_arttext&pid=S2077-99172016000200006&lng=es&nrm=iso&tlng=es El objetivo de este trabajo fue evaluar el efecto de las fibras naturales obtenidas de residuos agroindustriales en la densidad, el gramaje y las propiedades mecánicas de las espumas termoprensadas elaboradas de almidón de especies nativas, como lo son el camote, la oca y la arracacha. El proceso de termoformado se llevó a cabo a una temperatura de 145 °C y una presión de 60 bar. El tiempo de horneado fue de 10-15 min dependiendo del contenido de agua en la mezcla. Las bandejas fueron caracterizadas por su densidad, gramaje, ensayo de impacto, ensayos de deflexión, colorimetría y sus valores de dureza y fracturabilidad. Las bandejas elaboradas por termopresión a base de almidón de camote-fibra de bagazo de caña de azúcar al 15%, y de almidón de arracacha-fibra peladilla de espárrago al 30% presentaron mayores valores en resistencia a la flexión frente a las elaboradas con otros tipos de almidones y fibras, incluyendo a pruebas en blanco. De manera general, la dureza de las bandejas se ve favorecida con el incremento de fibra, sin embargo, la fracturabilidad decrece o no mejora la integridad de la matriz polimérica. Los resultados mostrados en esta investigación permitirán la elaboración de bandejas biodegradables para distintas aplicaciones industriales.<hr/>The aim of this study was to evaluate the effect of natural fibers derived from agro-industrial waste in density, weight and mechanical properties of the termoprensadas foams made of starch native species, such as sweet potatoes, oca and arracacha. The thermoforming process was carried out at a temperature of 145 ° C and a pressure of 60 bar. The baking time was 10-15 min depending on water content in the mixture. The trays were characterized by their density, weight, impact test, deflection tests, colorimetry, hardness, and fracturability values. The trays prepared by thermopressure based on sweet potato starch-bagasse fiber from sugar cane at 15%, and arracacha starch -peladilla asparagus fiber at 30% had higher values in flexural strength versus those made with other types of starches and fibers, including blank tests. Generally, the hardness of the trays is favored with increasing fiber, however fracturability decreases or does not improve the integrity of the polymeric matrix. The results shown in this study allow the preparation of biodegradable trays for various industrial applications. <![CDATA[<b>The ultrasound technology for modifying enzyme activity</b>]]> http://dev.scielo.org.pe/scielo.php?script=sci_arttext&pid=S2077-99172016000200007&lng=es&nrm=iso&tlng=es Enzymes are protein complexes compounds widely studied and used due to their ability to catalyze reactions. The food processing mainly aims the inactivation of enzymes due to various undesirable effects. However, there are many processes that can be optimized by its catalytic activity. In this context, different technologies have been applied both to inactivate or to improve the enzymes efficiency. The Ultrasound technology emerges as an alternative mainly applied to achieve the enzyme inactivation. On the contrary, very few investigations show the ability of this technology under certain conditions to achieve the opposite effect (i.e. increase the catalytic activity of enzymes). The objective of this study was to correlate the ultrasonic energy delivered to the sample (J/mL) with the residual enzymatic activity and explain the possible mechanisms which results in the enzymatic activation/inactivation complex behavior. The activity of POD in coconut water was evaluated as a model. The enzymatic activity initially increased, followed by reduction with a trend to enzyme inactivation. This complex behavior is directly related to the applied ultrasonic energy and their direct mechanical effects on the product, as well as the effect in the enzymatic infinite intermediate states and its structural conformation changes. The obtained results are useful for both academic and industrial perspectives.