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Physicochemical and structural analyses were done of extruded snacks produced with two types of blue corn (hard and soft endosperm) combined with orange bagasse. Chemical composition, expansion index (EI), penetration force, water absorption index, and water solubility index values were calculated for all treatments. They were also analyzed with scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. Addition of bagasse increased crude fiber content and hardness in the extrudates. It also lowered the EI, resulting in harder products with higher numbers of pores per area but of smaller sizes than in the extrudates without bagasse. Both the X-ray diffraction patterns and infrared spectra showed the starch to lose its semicrystalline structure due to mechanical shearing and high temperature. Orange bagasse was successfully incorporated into extrudated snacks made with blue corn of different endosperm hardnesses. Blue corn is a viable base for extruded snacks, and orange bagasse is a potential source of low cost, natural source fiber.

The results of the present study indicate that glandless cottonseed meal (CSM) can be incorporated in extruded corn flour snacks at a 10% content level, which increases snack protein content to 12.8% and reduce fat content to 6.2%. To improve snacks’ nutritional quality, CSM and corn flour were extruded using a simple screw extruder. An expansion index (EI) ranging of 1.2 - 4.7 was obtained. Penetration force (PF) was 7 - 9 times harder than other extruded products. High extrusion temperature and high CSM concentrations decreased (<i>p</i> < 0.05) EI, water activity, and water absorption index. Higher CSM concentrations can be incorporated into extrudates if snacks are processed at higher extrusion moistures. CSM increased (<i>p</i> < 0.05) extrudates’ PF giving them a unique crunchy texture. CSM decreased (<i>p</i>< 0.05) extrudates’ water solubility index. Extrusion conditions used showed a 68.5% starch gelatinization, and a starch availability of more than 97%, which explains the high expansion index obtained

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One of the processes most used in biotechnology today for handling industrial liquid wastes is biological wastewater treatment. The efficiency and quality of its operation depends on the composition and activity of the microbial community that is present. The application of traditional and molecular techniques has provided a glimpse into the "black box" and has given information to improve the wastewater treatment process. However, bleach pulp and paper mill effluents require a better understanding of the active bacterial population. For the study of these microorganisms, molecular techniques have been used for more than 15 years. However, there has been a lack of knowledge of the physiological requirements and relations with the environment, which seems to be very difficult to obtain involving profile on the diversity. Nowadays, highthroughput sequencing technology is a promising method that makes it possible to identify the entire profile of microbial communities. In combination with fingerprint methods, this approach allows the identification and analysis of the whole biodiversity of microbial communities. In this review, several identification techniques will be discussed.