Pruteen

By this time, the product had proved, in continuing toxicity and feeding trials, to be safe and effective feed material.The process was patented and the trade name Pruteen given to the product A licence to sell the product as feed was granted by the Ministry of Agriculture, Fisheries and Food. 

To test for possible toxic effects, rats, mice, dogs, chickens pigs, and fish were fed Pruteen at various levels in their diet, ranging from 30% to 60%. Control animals were fed casein (milk protein) instead of Pruteen. Feeding periods ranged from 28 days to 3 years. The parameters measured are outlined below. 

A study comprising five laboratories was carried out on the accuracy and precision of protein amino acid analysis. An important conclusion reached was that it is necessary to examine both accuracy and precision to achieve maximum improvement in either129. A commercially available single-cell protein, Pruteen, was proposed as reference material for the determination of amino acids and other substances in food. This recommendation was the result of a five-year-long study on the stability of this particular protein130. 

Important progress was also made in chemical engineering, such as use of rotary compressors in ammonia synthesis or ICI s fermentation reactors in Billingham to produce the Pruteen protein from methanol reactors, having no mobile parts. 

Single-cell proteins such as ICI s Pruteen were produced through culturing microorganisms on a bed of organic material. 

Even when they are technologically sound, however, bioproducts may turn out to be economically uncompetitive. The profitability of 1-lysine from one year to the next, for instance, depends on soy market prices. In the same way, the single cell proteins which BP produced in 1963 in Lavera from a petroleum base, using a process developed by France s Champagnat, never managed to compete with soy cakes for animal food. ICI has also just been forced to close down its 50,000-ton Pruteen unit in Billingham. 

Single-Cell Protein. Systems involving single-cell proteins are often very large throughput, continuous processing operations such as the Pruteen process developed by I CL These are ideal for air-lift bioreactors of which the pressure cycle fermenter is a special case (50). 

The Pruteen process - a case study Summary and objectives Resource Material... 

Methanol, which is relatively easily derived from methane and is also readily purified, avoids some of the contamination problems of the higher, n-paraffin carbon sources. Also methanol is easily put into aqueous solution at any desired concentration. This is the basis of Id s process to manufacture protein from methanol using Methylophilus methylotrophus, on a scale of 30,000-50,000 tonne/year [66] (Fig. 16.9). Recombinant DNA technology was employed to raise the efficiency of methanol conversion by this organism. The dry product trade named Pruteen contains 72% protein and is suitable for animal feed supplementation. 

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