Effect of vermicompost, worm-bed leachate and arbuscular mycorrizal fungi on lemongrass (Cymbopogon citratus (DC) Stapf. ) growth and composition of its essential oil

The objective of this study was to investigate the effect of vermicompost, worm-bed leachate (WBL) and Glomus mosseae, an arbuscular mycorrhizal fungi (AMF), on growth of lemongrass (Cymbopogon citratus (DC.) Stapf). A response surface methodology, i.e. a three-level Box Benhen design with three repetitions and three blocks, was applied to optimize biomass production, essential oil yield and its composition. Application rates of Glomus mosseae were 0, 1 or 2 g plant-1, vermicompost 0, 5 or 10 g plant-1 and WBL 0, 10 and 20 percent. The AMF had no significant effect on the variables tested, but vermicompost had a significant effect on essential oil yield and WBL on essential oil yield, myercene concentration and shoot dry weigh (p < 0.05). It was found that lemongrass fertilized with 2.0 g G. mosseae, 5.0 g vermicompost and 20 percent worm-bed leachate would yield 0.797 percent essential oil of which 62.6 percent was citral.

Spray-drying of passion fruit juice using lactose-maltodextrin blends as the support material

The objective of this study was to assess the effectiveness of the blends with different levels of lactose-maltodextrin (8:5, 10:5, and 12:5 percent w/v) during the spray-drying of the passion fruit juice. The drying was carried out in a laboratory spray dryer (Pulvis GB 22 model) at two inlet air temperatures (180 and 190 ºC), and two air pressures (0.10 and 0.20 MPa). The moisture content, hygroscopicity and vitamin C retention were evaluated in the powder obtained. Response surface plots (p<0.05) showed that the lowest values of the moisture content and hygroscopicity were reached in the temperature range of 188-190 ºC and at 12:5 percent (w/v) concentration of lactose-maltodextrin; the best vitamin C retention level occurred at 180 ºC and 0.2 MPa.

O objectivo deste estudo foi a avaliação da efectividade das misturas en diferentes níveis de lactose-maltodextrina (8:5, 10:5, 12:5 por cento w/v) durante a pulverização do sumo de maracujá. A secagem foi feita em um atomizador de laboratório de pulverização (modelo Pulvis GB 22) com 2 entradas de temperatura de ar (180 e 190 ºC), e 2 compressores de pressão de ar (0.10 e 0.20 MPa). O índice da mistura, higroscopicidade e retenção de vitamina C foram avaliados no pó obtido. As curvas de superfície de resposta (p<0.05) mostram que os valores mais baixos do índice da mistura e higroscopicidade foram alcançados no intervalo de temperatura de 188-190 ºC e com uma concentração de 12:5 por cento w/v de lactosemaltodextrina; o melhor nível de retenção de vitamina C ocorreu a 180 ºC e 0.2 MPa.