Andréa da Silva Lima

Estudo das variáveis de processo sobre a cinética de desidratação osmótica de melão

Osmotic dehydration represents a technological alternative to reduce post-harvest losses of fruits. The purpose of this work was to evaluate the influence of the osmotic solution concentration, fruit to osmotic solution ratio and system pressure on kinetics of the osmotic dehydration of melon. It was used 45o, 55o and 65oBrix sucrose solutions at 65oC, and 1:2 and 1:4 fruit to osmotic solution ratios. The osmotic treatments were carried out under atmospheric pressure and vacuum, for five hours. The use of vacuum in the osmotic dehydration of melon intensified the mass transport flows in the system when compared with the ones under atmospheric pressure, in the same conditions of concentration and fruit to osmotic solution ratio. The osmotic treatment under vacuum, which used 65oBrix sucrose solution and 1:4 fruit to osmotic solution ratio, showed be efficient for speeding up the water loss of the product, making possible to reach high degree of dehydration with a relatively small solids gain, in a shorter period of time when compared with the others treatments studied. The kinetics of the osmotic dehydration of melon is influenced by the process conditions, specially by the system pressure and osmotic solution concentration.

Desenvolvimento de bebida mista à base de água de coco e suco de acerola

Considering the great industrialization potential of coconut water and acerola juice and their functional properties, the objective of this work was to develop a ready-to-drink blended beverage based on coconut water and acerola juice and to evaluate its storage stability during 180 days at room temperature (28 ± 2 °C). Four formulations with 25 and 30% proportions of juice and total soluble solids (10 and 12 °Brix) were prepared, heated to 90 °C for 60 seconds and packed in glass bottles. The samples were submitted to chemical and physicochemical characterization (pH, acidity, soluble solids and vitamin C) and sensory evaluation (color, flavor and global evaluation). The best formulation was evaluated through chemical, physicochemical, sensorial and microbiological analyses during 180 days of storage. The beverage prepared with 30% acerola juice and sucrose added up to 12 °Brix presented the highest flavor and global evaluation scores when compared to the other samples. The blended beverage was stable with respect to pH, acidity, soluble solids and total sugars. Vitamin C, total anthocyanins and reducing sugars contents and color changed significantly along the 180 days of storage. The formulated beverage maintained microbiological stability. The sensorial evaluation showed that the blended beverage had good acceptability, especially during the first 90 days of storage.

Desidratação osmótica de manga seguida de secagem convencional: avaliação das variáveis de processo

A manga e uma fruta muito popular dos tropicos, consumida principalmente na forma in natura e com grandes possibilidades de industrializacao. A desidratacao osmotica seguida de secagem convencional tem se apresentado como uma ferramenta tecnologica importante no desenvolvimento de novos produtos, viabilizando o aproveitamento e valorizacao da manga. O presente trabalho teve como objetivo avaliar a influencia da concentracao do xarope osmotico e da pressao do sistema sobre a cinetica de desidratacao osmotica da manga, assim como sobre o processo de secagem subsequente. Verificou-se durante todo o processo a influencia das variaveis estudadas, notadamente da utilizacao de vacuo que possibilitou a reducao do tempo total de processo.

Estudo da estabilidade de melões desidratados obtidos por desidratação osmótica seguida de secagem convencional

The objective of the present work was to evaluate storage stability of melons processed by a previous osmotic dehydration at atmospheric pressure (760 mmHg) or partial vacuum (660 mmHg) followed by conventional drying. The stability was assessed monthly by means of physico-chemical, microbiological and sensorial methods, during 180 days of storage at room temperature. Both the processes resulted in good physico-chemical and microbiological stability of the products, which presented good acceptability during all the storage time.