Fractional composition of protein of frozen semi-finished products from champignon

Abstract

One of the most pressing issues of our time is the lack of protein, which is estimated at 15 million tons per year. According to scientist forecasts, 2/3 proteins of human needs in the future will be covered by industrial production of cultivated mushrooms. Witth the application of modern technology outcome of dry fiber per year is 63.5 kg per 1 ha.
In fungi nitrogenous substances are contained in the form of protein (70 % total) and intermediate products of protein metabolism (amines, ammonia, urea, free amino acids, etc.).
Assimilation of mushroom protein is within 54–85 % (average 70 %), vegetable – 61.6–72 % (average 68 %), animal – 95–98 % (average 96.5 %).
Purpose of the work is to study changes in the fractional composition (albumin, globulin, prolamin, hlyutelin and soluble proteins) protein in frozen preparations of cultivated mushrooms depending on the pretreatment of raw materials and the use of different types and concentrations of natural thickeners.
Object of study – cultivated mushrooms of white race strain A 15 with a closed cap and quick-frozen and semi-finished products.
Mass fraction of total nitrogen after freezing mushrooms is somewhat reduced compared to fresh. The smallest number of it is noted in the control variant, which was previously blanched. Adding to the pre-blanched mushrooms before freezing natural thickeners contributed to the maximum preservation of nitrogenous substances.
Mass fraction of protein nitrogen in frozen mushrooms of all types greatly exceeds that of non-protein. In terms of protein nitrogen for protein is revealed that most of it is contained in fresh mushrooms, slightly less (by 0.12–1.19 %) was observed in quickly frozen semi-products with added natural thickeners.
Total protein content in frozen mushrooms of control options (not blanched and blanched) was respectively 33.19 and 33 % on a dry weight.
Analysis of the protein fraction of fresh mushrooms showed little difference from the quick-frozen food after six months of low temperature storage. Absolute superiority of albumin, in second place – globulins. Significantly higher levels of albumin found in the variant semi-frozen using a mixture of хanthan gums, guar and lamidanu, due to the high content of amino acids in lamidan (13.6 %). Slightly smaller proportion of soluble proteins (22.08–32.10 % of the total protein), which consist mainly of glucose and fosfoproteyidamy. Best safety of albumin and globulins observed in mushrooms, pre-blanched with added natural thickener. The lowest share among proteins in fungi is prolaminy – alcohol-soluble proteins.
Thus, on the basis of the results it was found that the previous blanching before freezing cultivated mushrooms using polysaccharides of natural origin – хanthan gum, guar and lamidanu – helps maximize preservation of easily digestible protein fractions (albumin and globulin), which positively affects the nutritional value of frozen convenience foods. Prepared thus semis be recommended to the general population for the rapid preparation of various dishes.