Author(s): Maryam Shafaati, Niloofar Ahmadi, Mohammad Kargar, Marzieh Jamalidoust, Mansoor Khaledi, Hamed Afkhami
One of the main problem is the deficiency of water around the world which causes drought as well as vanishing natural resources, thereby this phenomenon has converted to the dearth of forage, animal feed, and destroying inhabitants, and it also is the major problem in fishery, domesticated animals, and poultry. Moreover, deficiency of protein sources, increasing population growth and high protein content of microbial cells have led to the utilization of other protein sources derived from microorganisms (as feed and food) rather than common protein sources. Single cell protein (SCP) is a microbial protein that is fermented by various microorganisms (bacteria, yeasts, fungi, or algae) on low-cost substrates like sulfate and industrial effluents and sewage, cellulose waste from paper mills, polishing, rice, beet pulp, molasses, bagasse, sugarcane, dairy industry waste (such as whey), agricultural waste (citrus waste) and animal fertilizer and liquor waste (as a carbon and energy source for biomass production, concentrate protein or amino acids) are obtained. The term is not appropriate for a substance with the protein content less than 65%. Nutritional deficiencies can be partially eliminated by consuming microbial proteins (SCPs).One of the most causes of those problems is the lack of water resources within the world and consequently, the occurrence of drought, and the loss of natural resources. This has led to the shortage of livestock feed, and therefore, the destruction of many habitats, becoming one of the most important concerns of the livestock, poultry, and fisheries industries. However, microbial protein is not popular as feed owing to the present low cost of other protein sources such as soy and fishmeal. In this study, the types of microorganisms and substrates available, the process of biomass production, nutritional value, safety, benefits, and limitations of SCP and products in good manufacturing practices (GMP) and their optimization were discussed.