Effects Of Heating Treatment And Superfine Pulverizing On The Physicochemical Property Of Dehulled And Non Dehulled Rapeseed Meals

The purpose of the experiment is to study the effects of heat treatment and superfine pulverizing on the functional properties of low-temperature defatted rapeseed meal(LTDRSM) with hull and dehulled rapeseed meal(LTDDRSM). The LTDRSM was finely ground into 4 sample groups with different geometric average particle sizes(13.2μm, 81.7μm, 138.9μm and 176.9μm) and the LTDDRSM was finely ground into 4 sample groups with different geometric average particle sizes(18.49μm, 73.03μm, 129.00μm and 184.05μm). Then these samples were treated with4 heating temperature( 60 ℃, 80 ℃, 100 ℃, 120 ℃) for 4 different heating times( 30 min, 60 min, 90 min, 120min). The functional properties including water absorbability(WA), oil absorbability(OA), emulsifying ability(EA) and emulsifying stability(ES) were tested, The digestive properties including protein solubility(PS)and protein digestibility in vitro(PD), amino acid availability(AAA), neutral detergent fiber(NDF) were analyzed. The antinutritional factors including tannic acid, phytic acid and isothiocyanate were also examined. The results showed that:(1)The influence of the superfine pulverizing and heat treatment on the functional properties of rapeseed meal(1) The biggest influence factors to WA, OA is Particle size. And the biggest influence factors to EA, ES is Heating temperature(2) For non dehulled rapeseed meal, the best treating conditions for WA are: particle size:176.92μm, heating temperature: 120 ℃, heat time: 120 min. The best treating conditions for OA are: particle size: 176.92μm, heating temperature: 120 ℃, heat time: 60 min. The best treating conditions for EA are: particle size: 13.76μm, heating temperature: 100 ℃, heat time: 90 min. The best treating conditions for ES are:particle size: 13.76μm, heating temperature: 100 ℃, heat time: 120 min.(3) For dehulled rapeseed meal, the best treating conditions for WA are: particle size:184.05μm, heating temperature: 120 ℃, heat time: 120 min. The best treating conditions for OA are: particle size: 73.03μm, heating temperature: 120 ℃, heat time: 90 min. The best treating conditions for EA are: particle size: 18.49μm, heating temperature: 120 ℃, heat time: 90 min. The best treating conditions for ES are:particle size: 129.00μm, heating temperature: 100 ℃, heat time: 60 min.(2)The influence of the superfine pulverizing and heat treatment on the digestive properties of rapeseed meal(1) The biggest influence factors to PS, PD and NDF,AAA is Particle size.(2) For non dehulled rapeseed meal, the best treating conditions for PS are: particle size: 13.76μm, heating temperature: 100 ℃, heat time: 60 min. The best treating conditions for PD are: particle size: 13.76μm, heating temperature: 100 ℃, heat time: 90 min. The best treating conditions for NDF are:particle size: 13.76μm, heating temperature: 120 ℃, heat time: 120 min.(3) For dehulled rapeseed meal, the best treating conditions for PS are: particle size: 18.49μm,heating temperature: 100 ℃, heat time: 120 min. The best treating conditions for PD are: particle size: 18.49μm, heating temperature: 60 ℃, heat time: 60 min. The best treating conditions for NDF are: particle size: 73.03μm, heating temperature:80 ℃, heat time: 30 min.(4) The sequence of influence factors to AAA is that :Particle size > heating temperature > heating time. And histidine, lysine, isoleucine,phenylalanine has low availability, serine, histidine, phenylalanine, histidine are influenced obvious by temperature processing.( 3) The influence of the superfine pulverizing and heat treatment on the antinutritional factors of rapeseed meal(1) The biggest influence factors to tannic acid is Particle size. And the biggest influence factors to phytic acid and isothiocyanate is Heating temperature.(2) For non dehulled rapeseed meal, the best treating conditions for tannic acid are: particle size: 13.76μm, heating temperature: 80 ℃, heat time: 60 min. The best treating conditions for phytic acid are:particle size: 176.92μm, heating temperature: 120 ℃, heat time: 120 min. The best treating conditions for isothiocyanate are: particle size: 176.92μm, heating temperature: 100 ℃, heat time: 30 min.(3) For dehulled rapeseed meal, the best treating conditions for tannic acid are: particle size: 18.49μm, heating temperature:60 ℃, heat time: 60 min. The best treating conditions for phytic acid are: particle size:18.49μm, heating temperature: 120 ℃, heat time: 120 min. The best treating conditions for isothiocyanate are: particle size: 18.49μm, heating temperature: 80 ℃,heat time: 30 min.(4)The influence of dehulling of rapeseed meals(1) Dehulling of rapeseed meals can reduce the WA, EA and ES, but the OA is increase.(2) Dehulling of rapeseed meals can increase PS, obviously reduce the content of NDF, and reduce the PD.(3)Dehulling of rapeseed meals can reduce the contents of isothiocyanate and tannic acid,increase phytic acid.