Biovalorization of brewers’ spent grain for the production of laccase and polyphenols

Brewers’ spent grain (BSG) is the main solid by‐product of the brewing process and is typically disposed of as cattle feed. In this study, BSG was evaluated as a substrate for the production of polyphenols and the lignin‐degrading enzyme laccase using fungal solid‐state fermentation by Trametes versicolor. Laccases are finding increasing applications in the food industry and polyphenols have benefits for human health. After 14 days of fermentation with T. versicolor, there was a 3.4‐fold increase in the extraction of total polyphenols compared with untreated BSG. Using BSG as the sole source of carbon and nitrogen, maximum laccase activity was achieved after seven days of treatment with an activity of 560 U/L. Based on these results, BSG is suggested to be a good lignocellulose waste material to produce value‐added products such as the enzyme laccase and polyphenols. Copyright © 2018 The Institute of Brewing & Distilling     

Discussion between alternative processing and preservation technologies and their application in beverages: A review

The alternative technologies discussed in this review are able to eliminate pathogenic bacteria while retaining bioactive compounds such as anthocyanins, phenols, pigments, and vitamins, improve the extraction processes of fruit or vegetable juices. The use of nonthermal processing technologies in beverages might provide a higher quality value to the final product and consumers tended to prefer more natural products with minimum preservative substances. This review is analyze and discuss the advantages and disadvantages of alternative technologies applied in beverages, evaluating the parameters that can optimize beverage processing such as time, temperature, pressure, frequency, tension, among others. Additionally, finding solutions to beverage processing issues will be considered analyzing the results obtained with other applied methods, and an overview of new strategies such as microfiltration or the combination of two alternative technologies to improve the quality of the final product will also be evaluated.

Practical applications

The applications of alternative technologies mentioned in this article, are a feasible option for the preservation of beverages in the area of industry. The capacity of each of them has been demonstrated, in addition to the use of microfiltration and ultrafiltration, but the combination between them sounds very encouraging to achieve the quality and safety of beverages, with an extended shelf life and greater protection of its main components. This provides a wide range of research opportunities for any type of beverage.     

Inhibitory effect of acid concentration,aging, and different packaging on Escherichia coli O157:H7 and on color stability of beef

The presence of pathogens such as Escherichia coli O157:H7 (EC) represents risks to public health and to economy of Brazilian beef industry. In this context, the application of lactic acid (LA) is an efficient practice employed to reduce bacterial count without compromising consumer safety. Our aim was to verify the inhibitory effect of LA application combined with aging and different packaging on EC and its effects on beef color. The LA effect on EC counts was concentration dependent during aging and storage, with T2 (10% of LA added) demonstrating greater (p < .05) reductions than T1 (5% of LA added). Aging did not affect (p > .05) EC counts, however reduced (p < .05) the total aerobic mesophilic bacteria. LA application promoted a decrease on beef redness (p > .05) after application and during storage. LA treatment (T2) promoted a reduction in E. coli O157:H7, despite the effects on beef color.

Practical applications

The present data evidence a breakthrough in lactic acid (LA) researches once evaluate the inhibitory effect of aging, LA concentration and package on Escherichia coli O157:H7 and the influence of these technologies in beef color. Moreover, the data presented allow clarifying the meat industry about the potential use of LA preservation on beef.     

NiCrSiBC alloy: microstructure and hardness of coatings processed by arc and laser

The processing technique is decisive for the characteristics of a coating. This is because the heat supply, which depends on the technique and on the parameters, has an influence on the dilution and the solidification rate. In alloys with low metallurgical complexity, the effect of processing with deposition techniques that give a higher cooling rate may be translated into refining of the microstructure. A more refined microstructure is expected to result in higher mechanical strength of the coating. However, in the deposition of alloys that are more complex metallurgically this does not always occur, because the high cooling rate may suppress formation/precipitation of phases responsible for strength. The influence of processing on the microstructure and hardness of coatings of alloy Colmonoy-6^® was assessed in this study. The alloy was processed by plasma transferred arc and high-power diode laser on plates of AISI 304 with two levels of dilution. In both cases, good-quality, defect-free coatings were obtained. Increase in Fe content (dilution) and different cooling rates result from processing with different parameters and techniques. This leads to significant changes in microstructure and hardness of the coatings, associated with the distribution, morphology and chemical composition of the carbides and particularly of the borides.     

Easy classification of traditional Minas cheeses using artificial neural networks and discriminant analysis

The classification of traditional Minas cheese (TMC) from different regions is important to ensure authenticity. Different chemometric approaches were used to discriminate TMCs from three different regions (Serro, Canastra and Araxá) of Minas Gerais, Brazil. The data obtained from the literature were used to develop an artificial neural network and to obtain linear discriminant functions, which were able to classify 100% of cheeses from different regions as a function of physico‐chemical composition. Both chemometric methods can be very useful tools to discriminate TMC from different regions based on physico‐chemical data which are obtained in a very quick and simple way.