Already more than 25% of human population is suffering from hunger and malnutrition. Both human population and animal population are rising. Conventional agricultural produce of cereals, pulses, vegetables and fruits would not be able to meet the rising demand of food. It can be produced entirely independent of agricultural waste products. Further, stress of health advisers on meat diets is reducing the availability of cereals and other food articles because 3—10 kg of grains are required to produce 1 kg of meat from animal farming. SNPs usually develop after fermentation of waste materials providing all necessary conditions like temperature, humidity, water, pH etc. Even then the availability of animal protein cannot be abundant. A 250 kg cow produces only 200 g of protein per day while it eats 20—30 kg of food. Therefore alternative methods of raising food items have to be searched.One of them is single cell protein.

Single cell protein is protein rich cell biomass which is used as food or feed. It is a very successful example of naturally synthesized food. Basically the food which is produced has the texture of meat. It posses a lot of fiber. Animals such as cow buffalo need a large amount of protein. Earlier Spirulina, a cyanobacterjum (blue-green alga) has long been used as human food and fodder. Microorganisms are commonly used in raising fermented foods, e.g., curd, cheese, butter, bread. A number of other edible fungi (e.g., mushroom) and blue green algae are also known. It is a novel mechanism to fulfill not only the needs of our own but of animals too. The problem of lack of food is increasing day by day. In such condition, such techniques become an elixir for us to fulfill our basic needs in the coming future.

Efforts had been math to raise Chlorella as food. Spirulina can be grown on starch rich waste water of Potato processing industries, straw, molasses, animal manure and sewage. Doctors prefer food rich in protein, vitamins and minerals. Single Cell Protein stands perfectly to fulfill the condition. It can be a part of diet not only for children but also for sports person who in maintaining healthy diet and physical fitness. Spirulina is not only rich in protein, it also contains sufficient carbohydrates, fats, minerals and vitamins. To my knowledge, it is the first natural of deriving large amount of food in short period of time. It can be used as supplemented diet for undernourished children. Mushroom is already an acceptable food item. It is raised on waste organic matter. Therefore, nutrient rich microbes can also become an acceptable form of food. Their potential is quite high 250 g of bacterium Methylophilus methylotrophus grown on organic wastes.

Other microbial biomass can also be raised using low cost substrates. While algae do not require any organic materials in their substrates, other microorganisms (bacteria, yeast and other fungi) flourish on organic matter. Spirulina is recommended for diabetes patients to control blood sugar level. It has rare side effects. You my think for a while if the SNPs have any side effect. Let me make clear to you that SNPs are made from natural organisms without the use of chemicals, acids, enzymes etc. So the chances are rare. They are raised on low cost organic matter like that of saw dust, paddy straw, paddy husk and industrial organic wastes and effluents like whey. But minor symptoms like constipation , nausea may arise. But overall it is advantageous. With the development in the filed of biotechnology, the science behind SNPs will become more clear and better. The most common source of single cell protein are single celled yeasts and filamentous fungus. Single cell protein is rich in good quality protein. It is poor in fats. High protein and low fat are desirable features of human food. However, care has to be taken to remove excess nucleic acids and heavy metal or toxins present in organic wastes.

Single cell protein  actually means a protein rich biomass of unicellular microorganisms. However, it includes biomass of multi-cellular microorganisms as well. Some of its uses are:

1. It can be used as protein rich supplement of human diet. In broad spectrum, it can also used as carbon source including  waste product which helps in removal of pollutants.
2. It requires high level of sterility control to prevent infections an spoilage. This will bridge the gap between requirement and supply of protein for human diet and take off the pressure on agriculture system for increasing the protein content of food articles.
3. Use of organic wastes and industrial effluents in raising Single cell protein will help in reducing environmental pollution.

Certain algae grown in open ponds require only Carbon dioxide as the carbon source. In the presence of sunlight, they can effectively carry out photosynthesis, and produce protein. The examples of these algae are Chlorella species  and Spirulina species.  Chlorella is used as a supplement for enriching ice-creams, breads and yogurts in some countries. Overall, I would say that this technique deserves a serious consideration for its use as food or other supplement.