Microorganisms are the key role players in the fermentation process and in the production of fermentation products. As how they are beneficial in mediating the production of various valuable products, simultaneously we should know about the microbes that are capable of contaminating the product quality at as many possible ways and stages they can. So, the sterility of the product need to be checked at every step and quality check of the product need to done very rigorously to ensure the safety of product usage.