Märkäkuumennus tärkkelyksen entsymaattisen hajoamisen tehostajana II. Kotimaisista minkkien viljarehuista

Abstract

The cooking degree of cereal foods for mink, produced by four Finnish food mills, has been investigated. Data are presented on the digestibility of four cereal foods. The evaluation was based upon the fermentation of the starch by the amyloglycosidase method, without pre-gelatinization of the samples. The following results were noted: – The foods of mill C were well processed, i.e. 95—97 % of the starch was easily fermentable. Only these foods were in a flaked condition. – In the fresh state, one food of mill A displayed fairly good (92—95 %) fermentability, whereas two other foods from the same mill showed the poorest fermentability (about 38 %) in the test series. – The samples received from the two other mills (B and D) were of intermediate quality. – The fermentability of the foods from mill C was not reduced on storage. The fermentability of the best mill-A food was somewhat reduced (to about 80 %). On the other hand, all other foods became ’over aged’, the degree of aging being the greater the poorer the original hydro-thermal treatment. – The results obtained by amyloglucosidase, optical birefringence and the Congo-red staining method, respectively, were in general in agreement. The enzymatic method appeared to be suitable for quantitative determinations, whereas only rough estimations could be made by microscopy. – The digestibility of the starch in the freshly processed foods ranged from 97.0 to 98.6 %. Correspondingly, the digestibility of the organic matter ranged from 77.5 to 83.1 %. The lower figures relate to the less processed foods; nevertheless, the digestibility of all foods investigated can be considered good.