| Starch is an important raw material in food industry and is widely used.At present,there are a variety of starch-based food on the market,because of its delicate taste,smooth gel texture and the effect of inhibiting colon cancer,more and more consumers have been concerned.However,natural starch has some shortcomings such as easy change of quality and shearing resistance during aging process.Starch is usually modified by chemical,physical,enzymatic or compound methods to extend its application and delay the change of its quality during storage.In addition,chemical modification processing is highly polluting and enzyme modification cost is high,while adding some natural substances such as carbohydrates,amino acids and polyphenols into the starch system to modify the starch has the advantages of convenience,green and low cost.Therefore,this paper explores the modification effect of polyphenols on starch.Proanthocyanins(PAS),a kind of polyphenols,have remarkable physiological functions,in particular the ability to clear free radicals and reduce cardiovascular diseases.Therefore,procyanidins and typical starches(potato starch,pea starch,rice starch and corn starch)were selected as the research objects to study the effects of PAS on the physicochemical properties and digestive properties of different starches,so as to provide theoretical basis for the development of new starch-based foods with high nutrition,multi-function and suitable processing.The research results of this paper are as follows:Taking Potato starch(PS)as the research object,the effects of the addition of PAS on its physicochemical properties were studied.The results of the gelatinization study showed that the addition of PAS changed the starch pasting properties of PS,and the peak viscosity,final viscosity and breakdown value showed decrease and then increase tendency with the increase of the content of PAS,each value reached the lowest when the amount of PAS was 5%,decreased by 62.1%,24.2%,86.8%,respectively.The rheological result showed that PAS reduced the consistency coefficient(K)and the flow behavior index(n)of PS,with the addition of PAS,it showed a trend of first decreasing and then increasing.When the amount of PAS was 5%,The K and n values of upward and downward lines were reduced to the lowest,were 24.63,0.409(uplink);6.58,0.510(downlink),respectively.The storage modulus(G')and loss modulus(G")of the PAS-PS mixture system were higher than that of PS,PAS increased the viscoelasticity of PS.The results of Differential scanning calorimeter(DSC),Fourier infrared spectroscopy(FT-IR)and X-ray diffractometer(XRD)showed that as the additive amount increased from 2.5%to 5.0%and 7.5%,it decreased by 11.9%,18.3%and 16.0%respectively,PAS significantly reduced the order degree of the short-range crystals and the relative crystallinity of PS during the retrogradate process,the value of relative crystallinity decreased by 14.53%,29.33%,28.64%,respectively,indicating that PAS with different amounts of addition had a different degree of inhibition effect on the retrogradation of PS.The added amount reached 5%,and already showed the best inhibitory effect.When the added amount of PAS increases from 0%to 5%,the porosity of pores in the microstructure of PS increases,continue to add to 7.5%,the microstructure has no change.Therefore,the added amount of PAS was selected to be 5%for subsequent experiments.The effects of PAS on physicochemical properties of starch from different sources(rice,potato,pea)were studied.The research result showed that the addition of PAS significantly enhances the heat-resistant stability of Rice starch(RS)and PS,reduced the heat-resistant stability of Pea starch(PE),and inhibited the short-term retrogradation of the three starches,the setback value decreased by 10.7%,7.6%,16.5%,respectively.PAS changed the rheological properties of the three starches,the K value of RS decreased,the n value of RS increased,the K and n values of PS decreased,and the K and n values of PE increased.DSC measurement result showed that PAS increased the gelatinization temperature of PS and RS,but lowered the gelatinization temperature of PE.When added PAS,the enthalpy of gelatinization of RS,PS and PE was reduced by 18.2%,18.3%,and 2.4%,respectively,the reduction of the retrogradation rate of RS,PS and PE was 16.88%,19.05%,and 1.81%,respectively,showed PS had the most obvious inhibitory effect on retrogradation by adding PAS.XRD results showed that the relative crystallinity of PS,RS and PE decreased by 29.3%,24.7%and 3.5%,respectively.SEM result showed that the microstructures of PS and RS had significant changed when adding PAS,the pores increased and becomed larger,while the surface structure of PE was no obvious changed.The in vitro digestion result showed that the PAS and starch co-gelatinization has a stronger inhibitory effect on starch digestion than the PAS and enzyme mixed with each other on starch.The former increased the content of resistant starch components in RS,PS and PE by 18.79%,11.55%,26.96%,respectively.The latter increased the content of resistant starch components in the three starches by 13.12%,6.57%,and 20.13%,respectively,indicating that different addition order of PAS has different effects on starch digestion.To study the effect of PAS on the physicochemical and digestive properties of maize starch with different amylose content.In the measurement frequency range of 0.2-20 Hz,the tan? value of waxy maize starch(WAM)was decreased,and the tan ?value of High-amylose maize starch(HAM)was increased by adding 5%PAS,indicating that PAS enhanced the gel strength of WAM and decreased the gel strength of HAM.For the retrogradation properties of starch,PAS had a better effect on the inhibition of HAM retrogradation.The specific performance is that the absorption peak-to-peak height ratio of HAM at 1047cm-1/1022cm-1 decreased 4.3%,while WAM absorbs the peak-to-peak height ratio at this place reduced 2.1%.The relative crystallinity of the two starches decreased by 20.4%and 12.4%,respectively.The result of in vitro digestion showed that when PAS and starch were gelatinized together,it promoted the digestion of WAM and inhibited the digestion of HAM.Among them,the content of rapid digestion starch in WAM increased by 3.13%,and there was no significant difference in the content of resistant starch.The content decreased of rapid digestion starch in HAM decreased by 11.79%,and the resistant starch increased by 8.08%.Based on PAS influence on starch physicochemical properties.In this paper,the preparation of the rice starch jelly food,according to its sensory score and structure properties(hardness,elasticity,chewiness)evaluation of jelly food quality,formulation optimization results as follows:8%RS,1.6‰ PAS,0.1%citric acid,8%sugar,composite powder(RS:carrageenan)ratio of 4:0.5.The jelly prepared by this formula is of the best quality. 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