Enzymatic potential for the valorization of agro-industrial by-products.

Agro-industrial residues and by-products are a crescent environmental problem since they are often discarded without proper treatment, and still have growing production. These residues are rich from a nutritional point of view and contain various industrial relevant compounds, such as phenolic compounds, fibers, vitamins, sugars and others. The crescent worrying about environmental issues has led researchers and industries to focus on "eco-friendly" solutions for everyday problems. In this sense, the use of enzymes for the valorization of agro-industrial residues is a safe and green alternative technology. Hence, this review aims to show the enzyme potential for the use and valorization of several agro-industrial residues, focusing on the most produced residues worldwide, such as fruits, grains and lignocellulosic residues, as well as a brief explanation of microbial enzymes, its production and optimization, altogether with tools to identify producing microorganisms.

Nondairy ice cream based on fermented yam (Dioscorea sp.).

BACKGROUND: The demand for industrialized foods that contribute to health and well-being has characterized the new generation of consumers. Yam (Dioscorea sp.) is a nutritious food; however, it is not used very much in industrial food processes. The objective of this study was to develop and to characterize a truly dairy-free low-fat ice cream prepared from unfermented and fermented with yam dough. RESULTS: The fermentation was conducted by Leuconostoc lactic CCMA 0415 remained viable (107 CFU/g) during 90 days of storage. The fermentation process reduced the starch concentration from 26.82% to 22.35% and the protein concentration from 4.68% to 3.99% and increased the concentration of some minerals (K, S, Cu, Mn, Zn, and Fe). The total phenolic contents for fermented and unfermented ice creams were 51 and 54 mg, respectively. The radical scavenging activity were 18% and 10% with the 1,1-diphenyl-2-picrylhydrazyl method and 44% and 26% with the 2,2'-azino-bis (3 ethylbenzo-thiazoline-6-sulfonic acid) method for the unfermented and fermented samples, respectively. The fermented and unfermented ice creams were both characterized as non-Newtonian fluids exhibiting pseudoplastic behaviors. CONCLUSIONS: These results indicated that yam is a suitable substitute for milk, thus making it an option to produce edible lactose-free ice cream with low fat.

Sensorial, antioxidant and antimicrobial evaluation of vinegars from surpluses of physalis (Physalis pubescens L.) and red pitahaya (Hylocereus monacanthus).

BACKGROUND: To reduce postharvest losses, substandard fruit and agricultural surpluses can productively be used as raw material for vinegar production. The present study aimed to prepare vinegars from surpluses of physalis (Physalis pubescens L.) and red pitahaya (Hylocereus monacanthus) and then evaluate their sensorial characteristics, antimicrobial activities, total phenolic content (TPC) and total antioxidant capacity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzo thiazoline-6-sulfonic acid) methods. RESULTS: Two vinegars were produced by submerged fermentation using physalis and red pitahaya fruits surpluses. Physalis and red pitahaya vinegars had 47 and 45 g L-1 acetic acid, respectively, and both vinegars contained approximately 1 g L-1 ethanol. Both vinegars displayed antimicrobial activity against Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Salmonella enteritidis. The TPC of physalis and red pitahaya vinegar was 0.5638 and 0.3656 g L-1 g gallic acid L-1 for physalis and red pitahaya, respectively. A similar antioxidant activity was detected in both the wines and vinegars. The sensorial analysis revealed that the consumers 'like moderately' each vinegar, and citric aroma was noted in the physalis vinegar. CONCLUSION: In the present study, vinegars with sensorial characteristics approved by consumers were developed using fruit surpluses, adding value through a new product making use of a simple methodology that is both inexpensive and demonstrates a good yield. © 2018 Society of Chemical Industry.

Microbiological and chemical characteristics of tarubá, an indigenous beverage produced from solid cassava fermentation.

The aim of this work was to identify and characterize the microbiota present during fermentation and in the final beverage, tarubá, by culture-dependent and -independent methods. In addition, target chemical compounds (carbohydrates, organic acids, and ethanol) were evaluated. Lactic acid bacteria (LAB) and mesophilic bacteria were the predominant microorganisms. Among them, Lactobacillus plantarum, Lactobacillus brevis, Leuconostoc mesenteroides, and Bacillus subtilis were frequently isolated and detected by DGGE analysis. Torulaspora delbrueckii was the dominant yeast species. Yeast isolates Pichia exigua, Candida rugosa, T. delbrueckii, Candida tropicalis, Pichia kudriavzevii, Wickerhamomyces anomalus, and Candida ethanolica and bacteria isolates Lb. plantarum, Bacillus subtilis, Bacillus amyloliquefaciens, Bacillus licheniformis, Bacillus sp., and Chitinophaga terrae showed amylolytic activity. Only isolates of P. exigua and T. delbrueckii and all species of the genus Bacillus identified in this work exhibited proteolytic activity. All microbial isolates grew at 38 °C, and only the isolates belonging to Hanseniaspora uvarum species did not grow at 42 °C. These characteristics are important for further development of starter cultures; isolates of T. delbrueckii, P. exigua, and Bacillus species identified in this work displayed all of these properties and are potential strains for use as starter culture in cassava fermented food.