Effects Of Conditioning And Expansion Treatment On The Physicochemical Properties Of Different Particle Size Rapeseed Meal

The purpose of the experiment is to study the effects of conditioning and expansion treatment on the physicochemical properties of different size low-temperature defatted with hull and dehulled rapeseed meal. The sample was finely ground into 3 geometric average particles groups.Size of hull rapeseed meal is 69.04,123.50,191.63μm. Size of dehulled rapeseed meal is 72.42,133.01,183.54μm. In the first experiment,these samples were treated with 0.1, 0.15, 0.2 MPa steam pressure and added 5%, 7% and 9% of steam and three conditioning times(60, 90, 120s) separately. In the second experiment, three size groups of with hull and dehulled rapeseed meal were extruded under 120, 140, 160 ℃with7%,10%,13% of the water added. The functional properties including water absorbability(WA), oil absorbability(OA), emulsifying ability(EA), emulsifying stability(ES), protein solubility(PS), protein digestibility in vitro(PD), dry matter digestion rate(DD), Neutral Detergent Fiber(NDF), tannin, isothiocyanate fat(ITC) and oxazolidine thione(OZT) were tested and analyzed. The results showed that:Conditioning time is the main impact factor for hull rapeseed meal’s ES and dehulled rapeseed meal’s EA. Steam addition amount is the main impact factor for hull rapeseed meal’s EA.Vapor pressure is the main impact factor for hull rapeseed meal’s PD and dehulled rapeseed meal’s tannin. Size is the main impact factor for two kinds of rapeseed meal’s other indicators of measurement.The optimal conditioning condition of hull rapeseed meal is that the particle size is 191.63μm, conditioning time120 s, vapor pressure 0.10 MPa, the steam addition amount was 5%. The optimal conditioning condition of dehull rapeseed meal is that the particle size is 72.42μm, conditioning time60 s, vapor pressure 0.10 MPa, the steam addition amount was 5%.Expansion temperature is the main impact factor for hull rapeseed meal’s PD、NDF and dehulled rapeseed meal’s WA,OA,PS,PD,DD,ITC,OZT. Water addition amount is the main impact factor for hull rapeseed meal’s PS,DD,ITC,OZT and dehulled rapeseed meal’s tannin. Size is the main impact factor for hulled rapeseed meal’s WA,OA,tannin and dehulled rapeseed meal’s NDF.The optimal expansion condition of hull rapeseed meal is that the particle size is 123.50μm, water addition amount13%, Expansion temperature120℃. The optimal expansion condition of hull rapeseed meal is that the particle size is 72.42μm, water addition amount13%, Expansion temperature 120℃.