Research About Effects Of Persimmon Juice On The Flour And Flour Products Quality

For the poor quality and weak tenacity of gluten, the domestic wheat flour does notmeet to be used as the feedstock of wheat flour food. An effective means to improve doughand flour products is to add Improver. In this study，the starting point is to improve thequality of wheat flour, Beijing Gucheng wheat flour as raw material, to study the effects ofdifferent tannin addition and different solid-liquid ratio of different maturity persimmonjuice on the rheological property and wheat flour food quality as the intention. In order toinvestigate the effects of tannin and persimmon on the flour rheological property, fourconcentrations of0.05%,0.1%,0.2%and0.3%of tannin and three maturity (low maturitypersimmon LP, the high maturity persimmon MP, ripe persimmon HP) of solid-liquidratio1:10,1:15,1:20persimmon juice were added to the flour, farinograph property,extensograph property and textual property including. As the same time, explore the effectof different concentration of tannin and different maturity of different solid to liquid ratiopersimmon juice on bread and steamed bread quality, specific volume, color and texturecharacteristics including. The main conclusions of this study are as follows:1. The result of farinograph property of adding different concentrations of tannin anddifferent maturity levels and different solid-liquid ratio of persimmon juice by Farinographshowed that, Add different concentrations of tannin, water absorption little change; doughstability time, dough development time and the mixing tolerance index with the flour wereincreased with the increasing added amount of tannin, softness was decreased with theincreasing added amount of tannin, showed that tannin has a good effect to improve thedough rheological property. Water absorption, dough stability time, dough developmenttime, softness and the mixing tolerance index of HP changed in unobvious way;solid-liquid ratio from1:10to1:20, water absorption of LP had a downward trend, MP firstdecreased and then increased, reached its lowest point at1:15; stability time of MP and HPhad a downward trend; dough development time of LP had a downward trend, themaximum of MP at the solid-liquid ratio1:15; mixing tolerance index, LP and HP was in adownward trend, and index of all samples are higher than the control group, The highestscore is LP1:20, increase of21.51%than the score of the control group. Instructions toadd the Different maturity solid to liquid ratio persimmon juice have improved the qualityof wheat flour role, especially LP1:20the best. The effect of adding persimmon juice on water absorption larger than adding tannin, the effects of adding persimmon juice ondevelopment time are similar to adding tannin, the effect of adding persimmon juice onstability time, softness and the mixing tolerance index are less than that of tannin. Whichindicates that adding persimmon juice can improve the quality of wheat flour, but the effectis smaller than tannin, add persimmon juice wins in the stable effect.2. The result of extensograph property of adding different concentrations of tannin anddifferent maturity levels and different solid-liquid ratio of persimmon juice by Extenographshowed that, add different concentrations of tannin, extensibility，tensile resistance，ratiofigure，maximum tensile resistance and tensile energy of dough with the flour wereincreased with the increasing added amount of tannin and extension with proofing time.Show that with the increase of tannin, dough energy enhanced, wheat flour gluten strengthenhanced. Add persimmons juice of different maturity and different solid-liquid ratio,extensibility，tensile resistance，ratio figure，maximum tensile resistance and tensile energyof dough with extension with proofing time. Solid-liquid ratio from1:10to1:20,extensibility and ratio figure of LP, MP, HP increased; tensile resistance and tensile energyhad no trend, but all samples were higher than control group. Add the persimmon juice,minimum of tensile resistance for230.5EU was38.02%higher than that of control group;The minimum tensile energy was1:15of MP and1:20of HP in45min,51.52%more thanthe control group. This indicates that adding persimmon has a good effect on the tensileindex of wheat flour, can enhance the firmness of the gluten network structure of wheatflour and the capacity of gas. And extensograph property had the relationship withfermentation time and persimmon juice concentration, fermentation time135min isappropriate. Adding persimmon juice and tannin have a positive effect on the extensographproperty, we can say that persimmon juice and tannin can improve the quality of wheatflour. But the effect of adding persimmon juice on extensograph property is not larger thanadding tannin.3. The result of textual property of adding different concentrations of tannin and differentmaturity levels and different solid-liquid ratio of persimmon juice by Textural Analyzershowed that, add tannin can make hardness of dough decrease, the elasticity and maximumadhesiveness increase. Adding persimmon juice had a bad effect on dough hardness andspringiness, but the maximum adhesiveness was improved significantly.4. The result of quality of flour products of adding different concentrations of tannin anddifferent maturity levels and different solid-liquid ratio of persimmon juice by TexturalAnalyzer and Color Difference meter showed that, after adding tannin specific volume ofbreads and steamed breads increased. The bread cores and steamed bread cores becamedark and black. The textual of bread core and steamed bread core, with the increase oftannin hardness, chewiness and adhesiveness of breads and steamed breads decreased,springiness first increased and then decreased. Add persimmons juice of different maturity and different solid-liquid ratio, specific voluMe of add persiMMon juice breads in additionto MP and HP of1:10were larger than the control group, but specific volume of LP1:20and MP1:20are larger than the maximum specific volume of adding tannin; specificvolume of add persimmon juice steamed breads were larger than the control group, andpersimmon juice can achieve better effect than tannin. LP on breads and steamed breadshave less effect on the color aspect,△E of bread that solid-liquid ratio1:20is only1.54,△E of steamed bread that solid-liquid ratio1:20is only2.24, relatively close to the controlgroup, and compared to tannin adding the persimmon juice bread and steamed bread aremore close to the control group in the color, more easily accepted by people. The physicalproperties, Add persimmons juice of different maturity and different solid-liquid ratio,bread hardness, chewiness and adhesiveness increased, little change in springiness;hardness of MP1:20and all HP steamed breads were less than the control group,adhesiveness of LP1:15,1:20and MP1:15,1:20steamed breads were less than the controlgroup. Adding tannins can improve the quality of the bread and reduce the quality of thesteamed bread, but adding persimmon juice on the contrary, have a bad effect on bread anda good effect on the steamed bread.