Effect Of Concentration-induced Sodium Alginate Gel On The Retrogradation Of Rice Starch

This topic firstly explored the conditions and concentrations of sodium alginate and calcium ions gel,and then established the rice starch gelatinization and sodium alginate-calcium ions gel system.Secondly,the topic studied the effect of concentration-induced alginate gel on the retrogradation of rice starch using a variety of modern analytic instruments and finally applied the concentration-induced alginate gel in fresh wet rice noodles to provide a theoretical basis for actual production.The main research results are as follows:1)The sodium alginate concentration between 0.3%?1.0%and calcium ions concentration between 2.0?4.0mmol/L can form gel via any ratio through concentration-induced.2)Rapid viscosity analyzer(RVA)results showed that the sodium alginate can increase the viscosity of starch paste by 87.4%while sodium alginate and calcium ions together can increase the viscosity of starch paste by 46.6%?58.6%;Sodium and sodium alginate-calcium ions can reduced the breakdown value and delayed peak time durning rice starch gelatinization.Rheometer results showed that 4%rice starch could present gel properties only by adding sodium alginate and calcium ions at the same time.Scanning electron microscope(SEM)observed that the pasted rice starch which include alginate sodium and calcium ions can form irregular mesh structure and rice starch evenly dispersed in the structure.In conclusion,the experiment proved that sodium alginate interact with calcium ions in the process of rice starch pasting,the two can form gel when the degree of concentration-induced is enrich,the gel form process and rice starch past process can occure at the same time.3)Differential scanning calorimeter(DSC)results showed that concentration-induced sodium alginate could significantly decrease the setback rate from 61.08%to 38.04%.The gel induced the retrogradation process of rice starch samples from a nucleation to multiple nucleations and reduced the rate of crystal nucleus growth.The gel could increase water hold ability and decreased the leak of amylase of rice starch.Enzymolysis experiments found that adding sodium alginate and calcium ions to rice starch could increase digestion rate and more digestible starch conversed into slowly digestible starch.SEM observed that the pore of original rice starch is bigger while the structure of rice starch containing sodium alginate gel is more compact after retrogradation.The concentration-induced sodium alginate gel can decreased the starch crystallinities from 21.52%to 9.56%?17.79%.4)Added concentration-induced sodium alginate gel to rice noodles,the resusts showed that the gel could improve the taste and organization status.However alone add sodium alginate to rice noodles can singinificantly improved the viscosity of rice noodles that induced the rice noodles easily adhesion during storage.Detected different period amylase content and reducing suger content proved that the gel has the ability to resistant rice starch retrogradation.TA results showed that the concentration-induced sodium alginate gel can be used as inhibitor in rice products.