Enzymes from Cereal and Fusarium Metabolism Involved in the Malting Process – A Review

Exploring the extraction, functional properties, and industrial applications of papain from Carica papaya

Papain a protease enzyme naturally present in the Carica papaya has gained significant interest across several industries due to its unique properties and versatility. The unique structure of papain imparts the functionality that assists in elucidating how papain enzyme works and making it beneficial for a variety of purposes. This review highlights recent advancements in papain extraction techniques to enhance production efficiency to meet market demand. The extraction of papain from the Carica papaya plant offers various advantages such as cost-effectiveness, biodegradability, safety, and the ability to withstand a wide range of pH and temperature conditions. Key findings reveal that non-conventional papain extraction techniques offer significant advantages in terms of efficiency, product quality, and environmental sustainability. Furthermore, papain treatment enhances the value of final products due to its anti-bacterial, anti-oxidant, and anti-obesity properties. The ability of papain to hydrolyze a wide range of proteins across various conditions makes it a suitable protease enzyme. While the study emphasizes the advantages of papain, the study also acknowledges limitations such as the continuous research and development to optimize extraction processes which will help unlock papain's potential and meet the growing demand. © 2024 Society of Chemical Industry.

The effect of seed germination and Bacillus spp. on the ripening of plant cheese analogs

Consumer demand for plant cheeses is increasing, but challenges of improving both flavor and quality remain. This study investigated the microbiological and physicochemical impact of seed germination and fermentation with Bacillus velezensis and Bacillus amyloliquefaciens on the ripening of plant cheese analogs. Chlorine treatment or addition of Lactiplantibacillus plantarum and Lactococcus lactis controlled microbial growth during seed germination. Lp. plantarum and Lc. lactis also served as starter cultures for the acidification of soy and lupine milk and were subsequently present in the unripened plant cheese as dominant microbes. Acidification also inhibited the growth and metabolic activity of bacilli but Bacillus spores remained viable throughout ripening. During plant cheese ripening, Lc. lactis was inactivated before Lp. plantarum and the presence of bacilli during seed germination delayed Lc. lactis inactivation. Metagenomic sequencing of full-length 16S rRNA gene amplicons confirmed that the relative abundance of the inoculated strains in each ripened cheese sample exceeded 99%. Oligosaccharides including raffinose, stachyose, and verbascose were rapidly depleted in the initial stage of ripening. Both germination and the presence of bacilli during seed germination had impact on polysaccharide hydrolysis during ripening. Bacilli but not seed germination enhanced proteolysis of plant cheese during ripening. In conclusion, the use of germination with lactic acid bacteria in combination with Bacillus spp. exhibited the potential to improve the quality of ripened plant cheeses with a positive effect on the reduction of hygienic risks.

IMPORTANCE

The development of novel plant-based fermented food products for which no traditional templates exist requires the development of starter cultures. Although the principles of microbial flavor formation in plant-based analogs partially overlap with dairy fermentations, the composition of the raw materials and thus likely the selective pressure on the activity of starter cultures differs. Experiments that are described in this study explored the use of seed germination, the use of lactic acid bacteria, and the use of bacilli to reduce hygienic risks, to acidify plant milk, and to generate taste-active compounds through proteolysis and fermentative conversion of carbohydrates. The characterization of fermentation microbiota by culture-dependent and culture-independent methods also confirmed that the starter cultures used were able to control microbial communities throughout 90 d of ripening. Taken together, the results provide novel tools for the development of plant-based analogs of fermented dairy products.

Prevalence of Fusarium fungi and Deoxynivalenol Levels in Winter Wheat Grain in Different Climatic Regions of Poland

Fusarium head blight (FHB) caused by fungi of the genus Fusarium is one of the most dangerous crop diseases, which has a wide geographic distribution and causes severe economic losses in the production of major cereal species. The infection leads to the accumulation of mycotoxins in grains, which compromises its suitability for human and animal consumption. The study demonstrated that grain samples from warmer regions of Poland, including Sulejów and Tomaszów Bolesławicki (results differed across years of the study), were colonized mainly by F. graminearum and were most highly contaminated with deoxynivalenol (DON). Samples from Northeastern Poland, i.e., Ruska Wieś, which is located in a cooler region, were characterized by a predominance of Fusarium species typical of the cold climate, i.e., Fusarium poae and Penicillium verrucosum. A Spearman's rank correlation analysis revealed that the severity of grain infection with F. avenaceum/F. tricinctum was affected by the mean daily temperature and high humidity in May, and the corresponding values of the correlation coefficient were determined at R = 0.54 and R = 0.50. Competitive interactions were observed between the F. avenaceum/F. tricinctum genotype and DON-producing F. culmorum and F. graminearum, because the severity of grain infections caused by these pathogens was bound by a negative correlation.

Relevant Fusarium Mycotoxins in Malt and Beer

Mycotoxins are secondary fungal metabolites of high concern in the food and feed industry. Their presence in many cereal-based products has been numerously reported. Beer is the most consumed alcoholic beverage worldwide, and Fusarium mycotoxins originating from the malted and unmalted cereals might reach the final product. This review aims to describe the possible Fusarium fungi that could infect the cereals used in beer production, the transfer of mycotoxins throughout malting and brewing as well as an insight into the incidence of mycotoxins in the craft beer segment of the industry. Studies show that germination is the malting step that can lead to a significant increase in the level of all Fusarium mycotoxins. The first step of mashing (45 °C) has been proved to possess the most significant impact in the transfer of hydrophilic toxins from the grist into the wort. However, during fermentation, a slight reduction of deoxynivalenol, and especially of zearalenone, is achieved. This review also highlights the limited research available on craft beer and the occurrence of mycotoxins in these products.