Flash vacuum expansion, a low-cost and energy-efficient alternative process to produce high-quality fruit puree: Application to Physalis peruviana.

Goldenberry has great potential for the development of high-quality products due to its attractive sensory attributes, bioactive compounds, and health benefits. However, postharvest losses are high due to the lack of processing technologies that can both be adapted to rural conditions in producing countries to generate high-quality products. Flash vacuum expansion coupled with vacuum pulping is a new process that can meet these requirements. In the process, the steam holding time (30, 40, and 50 s/130 kPa) and flash vacuum expansion (5 ± 1.2 kPa) were studied. The logarithmic reduction of microbial load and some quality indicators were analyzed during the process and during storage to assess the shelf life of fruit purées. The FVE process with 40 s steam blanching led to a microbial reduction of over 6 log colony forming units (CFU)/g, increased yield and ß-carotene content, and preserved most of the AA content (4-12%). Based on the half-lives of the quality indicators, the shelf life of the purées was between 16 d (20 °C) and 90 d (4 °C). The energy consumption was estimated at approximately 0.30 kWh/kg of product. These results demonstrate that the FVE process, although it includes heat treatment, allows a short exposure to heat of the whole fruits to obtain a high-quality puree with an adequate shelf life in a single step, with a relatively low equipment investment and moderate energy consumption.

Innovative Process Coupling Short Steam Blanching with Vacuum Flash-Expansion Produces in One Single Stage High-Quality Purple Passion Fruit Smoothies.

Short steam blanching coupled with flash-vacuum expansion (FVE) and de-pulping was used to obtain purée from purple passion fruits discarded from the export chain. Different steam blanching holding times (80, 95, 110 s) were tested at pressure of 130 kPa. After FVE and vacuum de-pulping, fibers, anthocyanins, carotenoids, rheological properties, and microbial reduction were evaluated in the purées. Fruit purées are obtained with a much higher content of cell-wall and bioactive compounds compared to the fresh arils since part of the fruit shell is incorporated into the purée (approximately 20%), which greatly increases the yield of production. Purées exhibited increasing shear-thinning flow behavior with blanching holding time, resulting in a smoothie-like beverage. A reduction greater than 5 log10 CFU/mL was obtained for molds, yeasts, aerobic mesophilic, and coliforms for all the treatments. The shelf life of smoothies based on nutritional and sensorial quality was extended up to 90 days at refrigeration temperature.

Potato snacks added with active components: effects of the vacuum impregnation and drying processes.

Potato snacks can be used as an ideal strategy for nutrient delivery, since they are one of the most widely consumed products in the world. Due to fried snacks are known to be a significant source of fat intake, consumption is changing towards healthier alternatives. The aim of this research is to evaluate the effect of vacuum impregnation and three dehydration techniques: heated air drying, freeze drying, and microwave vacuum drying of the potato snack that has been fortified with active components: calcium and vitamins C and E. Vacuum impregnation was evaluated using the response surface methodology that had a central composite experimental design with the following independent variables: vacuum pressure, vacuum stage time, and atmospheric stage time. The following were the dependent variables: fraction and volumetric deformation in the vacuum stage and at the end of the process and effective porosity. Finally, a sensorial analysis was carried out on the dehydrated potatoes. The results of the optimal vacuum impregnation process conditions were: a vacuum pressure of 77.3 kPa for 3.0 min followed by 4.0 min at atmospheric pressure. The content of calcium, vitamin C, and vitamin E in the impregnated potato were 956, 472, and 35 mg 100 g-1 dry solids, respectively. The highest retention of the active components in snacks was obtained by the combination of vacuum impregnation and the dehydration techniques in the following order: freeze drying, microwave vacuum drying, and then heated air drying. It can be concluded that the integration processes give an added value to potato snacks due to the increased content of the active components; additionally, the vacuum impregnation process together with microwave vacuum drying was the alternative that had the highest sensorial acceptability.

Fortificación de hongos comestibles (Pleurotus ostreatus) con calcio, selenio y vitamina C / Fortification of edible mushrooms (Pleurotus ostreatus) with calcium, selenium and vitamin C

La ingeniería de matrices es una metodología de obtención de alimentos funcionales que utiliza la técnica de impregnación al vacío para incorporar componentes con actividad fisiológica en la estructura de los alimentos porosos. El objetivo de este estudio es desarrollar un producto mínimamente procesado con características funcionales a partir de la fortificación del hongo Pleurotus ostreatus, con calcio, selenio y vitamina C. Los resultados de la fortificación presentaron niveles de Ca y Se de 7.3 y 42.3 por ciento de la ingesta diaria recomendada IDR/100 g de hongos frescos, respectivamente. La Vitamina C al inicio del almacenamiento (4°C, 83 por ciento humedad relativa), presentó un 40 por ciento IDR/100 g de hongos frescos, y durante el almacenamiento la cinética de degradación se ajustó a una ecuación de orden cero. Los productos fortificados registraron pardeamiento (menor luminosidad (L*), más rojizas (>a*)), con mayor intensidad en la cara lisa (CL) que en la corrugada (CC) del hongo. La textura del producto fortificado no se vió influenciada por la disolución de impregnación, pero con el tiempo las muestras presentaron endurecimiento.

Alimentos funcionales: una historia con mucho presente y futuro / Functional foods: a history with a lot of present and future

La evolución de los hábitos nutricionales ha sido muy variable a través del tiempo, pero siempre soportada con el criterio básico de mantener la salud. Cada día las exigencias de los consumidores se dirigen más a la búsqueda de nuevos productos con propiedades funcionales que puedan proporcionar además del valor nutritivo, otros componentes con actividad fisiológica que permitan un mejor estado tanto físico como mental, reduciendo así el riesgo de enfermedades y alargando la vida al mismo tiempo que manteniendo su calidad. Esta revisión describe aspectos importantes de alimentos e ingredientes con características funcionales, a través del pasado, presente y futuro