Effects of dietary n-3 polyunsaturated fatty acids and ... - FINS

1 st WorkshopXIII International Feed Technology SymposiumFrom the obtained results it can be stated that the extruded products contained decreasedwater contents, decreased starch contents and increased total- and reducing sugarscontents if compared with the starting raw materials. This can be explained by effects ofthermal decomposition of starch that influences on the digestibility and utilization ofstarch [2, 12]. The increased sweetness, i.e. changes of sensory properties are exactly theresults of the physico-chemical changes of the starch component. Also, the bushelweight of the extrudates, if compared with the starting raw materials, are lower, being 92– 119 kg/m 3 .Microorganisms counts of the extruded mixtures of corn grits and bread crumbs ageoutlined in the Table 6.Table 6. Microorganisms counts in the mixtures of corn grits and bread crumbsCountMicroorganismsExtruded ExtrudedSamplemixture corn mixture cornsizegrits : bread grits : breadcrumbs, 50:50 crumbs, 60:40Salmonella spp. 50 g Not found Not foundCoagulase-positive50 gNot found Not foundstaphylococciSulphite reducing clostridia 1 g Not found Not foundProteus spp. 50 g Not found Not foundEscherichia coli 50 g Not found Not foundTotal count of yeasts 1 g Not found Not foundTotal count of molds 1 g Not found Not foundTotal number ofmicroorganisms1741 g 40 20As can be seen on the basis of the obtained results, extrusion process as a consequencehad almost total reduction of molds, in spite of the comparatively low extrusiontemperatures 95 – 105°C and very short time of extrusion (6 – 10 s), but also, very highextrusion pressure, being 30 – 40 bar [5]. In the extruded mixtures, bacteria of the typesSalmonella spp., coagulase-positive staphylococci, sulphite reducing clostridia, Proteusspp., Escherichia coli, with exception of the total microorganisms number, which wassatisfactory according to the Rule book on the harmful matters and substances in theanimal feed (1990).CONCLUSIONThe extruded mixtures of corn grits and bread crumbs in the feed processing industryrepresent highly valuable energetic feeds. The extrusion process upgrades nutritive valueof the extruded mixtures of corn grits and bread crumbs because of the increasing ofquantities of the total and reducing sugars contents, as well as because of changes in thestarch complex of the extrudates, having a consequence the increases of the feeddigestibility, what is followed with the increase of yields. The thermal treatment in the