Analysis, Preparation And Properties Of Faba Bean Resistant Starch

This paper consists of eight chapters. The first chapter is literature review, which mainly outlines the faba bean nutritional and physiological characteristics, carbohydrates compounds, thephysiochemical properties of starch, the common determination methods of the resistant starch(RS), RS formation mechanism and preparation technology as well as factors influences RSyield; The second chapter reports the chemical composition of the faba bean and the separationprocess of faba bean starch; The third chapter analyzes physical and chemical properties of fababean starch; The fourth chapter compared the advantage and disadvantage of different methodsfor determinate of RS content; Chapter 5 and 6 study's the effect of autoclave and microwaveheat treatment on the of faba bean RS production; The seventh chapter investigates the effects offood components on RS yield; And the final chapter is the summary main result and conclusionobtained from this systematic study.The four varieties of faba bean Hebei chongli, Qinghai MaYa, Yunnan BaiPi, YunnanTouXinlv were obtained. No significant differences in the morphological characteristics betweenYunnan and Hebei varieties, but Qinghai is significantly bigger than the other three species offaba in size. There were no significant differences in chemical composition among this fourvarieties.The influences of different conditions on the separation of starch were studied with orthogonalimmersion test. The optimum parameters for starch separation were 80-100 mesh in size, inpH=10 calcium hydroxide solution soaked for 90 minutes at 25℃, and then 4,000 rpm for 15rain centrifugation, resulted in the starch yield of 67.84%.The starch physicochemical properties of the four varieties of faba bean were analyzed theirstarch. The starch granules are elliptical or irregular round shape, smooth surface, with sizebetween 12-32μm, settlement between 30-32 mL in 24 h, and more transparent than cerealstarch, but less than potato starch. And amylose content of 28-34%, a little bit less than lentilsand chickpeas starch.The molecular weight distribution of RS was measured by gel permeation chromatography,showed low temperature could not completely hydrolyze starch, indicating that partly resistant starch were not measured. Therefore the results obtained from this method are over valued. Thisproblem can be solved by heat-resistant enzymatic hydrolize.X-ray diffraction analysis of RS found that the RS of faba bean starch belongs to B-type X-raydiffraction. Pressure treatment completely destroyed the original starch structure of the crystalball, and produce a new crystals amylose.Scanning electron microscopy of faba bean starch and the original samples resistant starchobservation revealed that the pressure after heat treatment, starch granules of the originalstructure were completely destroyed by enzymes and resistant starch in the porous networkstructures did not exist. This shows that the majority of amorphous starch and the branched partof the retrogradation were break down. Resistance is mainly amylose crystals.RS samples of thermal analysis found that the resistant starch showed very good thermalstability (120℃), and tolerant to most of the food processing.The yield of faba bean RS was greatly effected by starch concentration, thermal pressure,temperature, retrogradation time and temperature.Starch concentration at lower than 30%, RS yield increased as the concentration increases.With further increase of the concentration ( greatly than 30%), RS yields begin to decline. Heattemperature at 125℃, RS reached the maximum yield. Temperature is too low or too highhindered the formation of RS. Pressure treatment over 45 rain, showed the decline trent for yieldof RS. The most appropriate heat treatment time and temperature were125℃for 45 min.Retrogradation temperature and time on the RS ultimately yield a significant impact. Under thedifferent temperature and time of detrogradation, a serializes occurred during starch molecularre-crystallization. The RS yield reaches the high level at 4℃for 24 h.Similar to the pressure- heat treatment with faba bean resistant starch, microwave radiationtreatmen has many factors impacting the yield rate: starch concentration, radiation, temperatureresuscitation, and resuscitation time. The optimum condition for microwave radiationpreparation of faba beanwere 30% of the starch solutioin, 6 rain microwave radiation, and then at4℃for 24 h of retrogradation.The role of NaCl during RS formation was inhibitor thereby improving the viscosity,increasing amylose retrogradation crystallization. Glucose has the mechanism similar to that of NaCl. When a glucose addition was less than 15%, it helps to form the RS, but high glucose andsodium chloride addition will have adverse impact.