Effects of Soybean Processing and Packaging on the Quality of Commonly Consumed Local Delicacy Tempe

Tempe is a processed food, produced by fermenting soybeans with fungus Rhizopus oligosporus. In this study, the effects of soybean processing (soaking, cooking and fermentation) and packaging (food grade wrapping paper, polyethylene bags and low density polyethylene cling wrap) on physicochemical properties, antioxidant activities and microbial count were evaluated. In addition, shelf life study of tempe samples (packed) was conducted for 1 week. Soaking and cooking significantly decreased polyphenols, flavonoids and antioxidant activities of soybeans. After fermentation, tempe samples exhibited significant improvement in physicochemical properties, antioxidant activities and extractability of polyphenols and flavonoids, when compared with unfermented soybeans. Food grade wrapping paper and perforated polyethylene bags were selected as suitable materials for packaging tempe as there were no significant changes in quality and the shelf life of tempe was extended for 3 days. Results obtained support the use of fermentation to improve the quality of soybeans along with safety standards. Practical Applications: Tempe processing and packaging plays an important role in extending the shelf-life of the product. The results of this study suggest that tempe samples exhibited significant improvement in antioxidant activities and extractability of polyphenols and flavonoids, after fermentation. Food grade wrapping paper and perforated polyethylene bags were selected as suitable materials for packaging tempe. This study could serve to improve the progress of processing and packaging for maintaining the quality of tempe

Avaliação do armazenamento a frio sobre os compostos bioativos e as características físico-químicas e microbiológicas do suco de umbu pasteurizado

Resumo Este trabalho teve como objetivo avaliar o efeito do armazenamento a 6 °C nas características do suco de umbu pasteurizado. A pasteurização foi realizada a 86 °C por 25 s em um pasteurizador de superfície raspada, sendo o suco de umbu mantido a 6 °C por 90 dias. O suco pasteurizado atendeu ao padrão estabelecido pela legislação brasileira com contagem <3 NMP.g-1 para coliformes a 45 °C e ausência de Salmonella sp. Nesta condição de processo, a pasteurização foi eficiente também para a redução de bactérias aeróbias mesófilas. O teor de compostos fenólicos totais e, em particular, da rutina, assim como a atividade antioxidante do suco, não foram afetados pelo tratamento térmico. Ao longo do armazenamento, apesar de não perceptível visualmente, os parâmetros de cor do suco variaram significativamente (p<0,05). Apesar de pequena, também houve variação significativa (p<0,05) nos teores dos compostos fenólicos e de carotenoides. Por outro lado, o suco de umbu se manteve microbiologicamente estável durante o armazenamento, sendo, portanto, possível sua conservação por um período de 90 dias sem o uso de aditivos, quando submetido à pasteurização e mantido sob refrigeração

In vitro gastrointestinal evaluation of a juçara-based smoothie: effect of processing on phenolic compounds bioaccessibility

In the present work, the bioaccessibility of the main phenolic compounds of a juçara, banana and strawberry homogenized smoothie (control), subjected to pasteurization and sonication, was evaluated. The smoothie was also evaluated in terms of its main chemical and physical characteristics. Pasteurized smoothie showed higher apparent viscosity, as well as higher initial shear stress when compared to the control and sonicated samples. The increase in the apparent viscosity of the pasteurized smoothie was associated with the smaller particle size of this sample (68 µm). These characteristics conferred to the pasteurized smoothie higher physical stability than the control and sonicated smoothies. Phenolic compounds bioaccessibility was higher in the pasteurized and sonicated smoothies than in the control sample, which confirmed the positive effect of the treatments for the preservation of these compounds after gastrointestinal digestion. Compared to the sonication process, the pasteurization provided higher total phenolic compounds bioaccessibility (47%), as well as of ferulic (16%) and ellagic (80%) acids. Antioxidant capacity was higher in gastric digest for all the samples evaluated by ABTS assay. These results confirm the importance of processing on the physical stability and phenolic compounds bioaccessibility of the juçara-based smoothie, standing out the thermally treated product.The authors are incredibly grateful to Federal University of Rio de Janeiro, Embrapa Agro indústria de Alimentos and University of Minho for support. Leilson O. Ribeiro acknowledge the Capes for his fellowship (88881.133775/2016-01) and Ana C. Pinheiro acknowledge the Foundation for Science and Technology (FCT) for her fellowship (SFRH/BPD/101181/2014).info:eu-repo/semantics/publishedVersio