The use of enzymes for improved production and enhanced quality of industrial products in particular fermented foods, received considerable attention of both academic studies as well as industries. This in turn, triggered interest in re-evaluating alternative new or existing technologies in the field of enzyme production. Solid State Fermentation (SSF) is briefly defined as the fermentation with far less (to almost no) free water when compared to the submerged fermentation. The sufficient amount of the moisture is needed to maintain cellular growth. SSF exhibits interesting features, e.g. considerably less water use, therefore more environmentally friendly, easier to downstream, decreased overall process cost, improved product stability, larger portfolio of enzymes or locally very specific productivity rates owing to the heterogeneity of the substrate of generation of sub-populations. This review lists and discusses the merits of the recent studies on the production of some of the well-studied enzymes in various industries, namely amylase, proteinase and pectinase via solid-state fermentation, vis-à-vis to various factors affecting the process e.g. moisture content, aeration rate, substrate particle size, temperature, and inoculum size. A separate focus is dedicated on the differences between submerged and solid state fermentation, not only from a fermentation unit operation but also from overall process design point-of-view. Lastly, we discuss the challenges in scale-up of SSF process and various reactor types.

Proteases are group of enzymes catalyzing the hydrolysis of proteins. Proteases are considered as commercially most significant among industrial enzymes with wide range of applications in several industries like food, detergent, textile, pulp and paper, and pharmaceutics. Enzymes can be produced by plants, animals or microorganisms, the latter being the dominant host, typically with modified features via recombinant DNA technology for high enzyme production. However, for e.g. food industry, the use of genetically modified microorganisms is not preferred, therefore isolation of new, wild-type microorganism for enzyme production is highly desired. Here we present the results of screening, isolation and characterization of new Bacillus spp. for protease production from soil samples from different areas in Kosovo. Soil samples were divided into four different groups according to their origin: (i) isolates from areas polluted by heavy industry, (ii) isolates from high altitude, (iii) loess sample near thermal water springs, and (iv) arable land. Strains with better protease activity, when compared to the reference strain is obtained.

Milk is a complex food product, with a high nutritional value. Milk produced from healthy cow is considered to be sterile, even though this is highly dependent on the environment of farm. Milk is processed to bring a cured with extend shelf life product. Pasteurization, is a curing process for milk based on thermal treatment, this process mostly inhibit the microbial growth but it does not destroy total microorganisms. Consequently, its shelf life is dependent on the storage parameters as temperature and time. Hence, the aim of our study was to analyze and prove indication of temperature and time by using statistical method called Response Surface Methodology (RSM). Experiments are designed with to independent variable temperature and time while as dependent variable is considered the total number of microorganisms (standard plate count). Results showed that storage temperature is the main factor that can extend the shelf life of the product, while for the predication of the shelf life of the product by using build equation by RSM, remains to be seen in future studies.