Research On Quality Characteristics Of Filter Flour And Extrusion Technology Of The Nutritional Food

In modern wheat milling industry, pneumatic conveying is widely used to transport thematerials. When wheat flour passes through the air separation devices as centrifugaldischarge or cyclone dust collector, etc., the weigh endosperm particles sink due to effect ofcentrifugal force, the fine fractions screw up with the airflow, eventually is collected byfilter bag. The collection is called customarily wheat filter flour. As a by-product of thewheat milling, although the output of the filter flour is only0.5%~1.5%of the processedwheat, it is a problem puzzling the wheat flour mills. In this paper, the qualitycharacteristics of filter flour and extrusion technology were researched, in order to knowdeeply the characteristics of air classification and broaden the application of filter flour.Contrastive analyses of filter flours and flours from different companies were made inthe basic content, gluten characteristic and color analysis. Result showed that: the generalcharacteristics of filter flours was low moisture, starch content, but more protein, fat, ashand damaged starch content than the flour, the average respectively was19.48%,1.87%,0.93%,14.23%. Especially, the protein content was up to26%, which was more than flour’s2times. The average of flour color of filter flour was79.04which close to flour. The peakviscosity of filter flours in RVA was low (average732.2cp); the stable time of dough waslonger, and the FQN was higher, with an average of189mm; the max resistance of everysample was more than500EU.Enormous differences were found in protein content and properties of filter flourswhich come from different milled stream. The filter flour from head milling road was theclosest to wheat flour. The filter flour from middle mill demonstrated the highest proteincontent and the strongest extensographic property (FQN280). The samples of the tail millinvolved lower starch content (55.7%), higher minera content (l1.03%), lipid content (2.4%),protein content (23.97%), and weak extensographic property.Filter flours were made to micro-puffed extrusion food that was obviously differentfrom flour products. The filter flour extrusion was low expansion (average190.3%), lowWAI (average285.7%), and WSI (average6.55%) was insignificant to flour products. Thehardness and chewiness of filter flour extrusion were larger. The expansion of extrudedproducts was positive correlation with water, starch, tolerance index and pastingtemperature, and negative correlation with protein content, FQN, and tensile energy value. The WAI of products was affected by lipid, starch content and FQN. WSI of the productwas subject to damaged starch clearly.By orthogonal experiment, the extrusion process with33%material moisture,135℃extrusion temperature and the frequency of14Hz can make the best extruded products.Theseasoning experiment based on sensory scoring can draw conclusions: the chili powder2.25%, the pepper powder0.5%and soybean oil16%can make the best chili oil. And thenadding MSG1.5%yeast extract things0.5%, sugar1%to the extruded food could the tastebest.