The Processing Of Baking Crisps With Green Tea And Determination Of Its Associated Indicators

Potato,as the forth of major grain crops,can provide large amount of nutrition to human.The development of potato products can improve the added value of the potatoes and the mid-low grade tea.When the green tea powder was added to the products,it not only provides the health care function to the products,but also extends the storage period of products,for the green tea powder containing a large amount of tea polyphenol,is an excellent antioxidant.To get the results,getting of potato powder,mixograph characteristics of potato powder and flour mixed powder,baking technology of baking crisps with green tea,storage characteristics and the quality were studied.The results are as follow.1)An analysis and research were conducted on the color protecting during the potato granules.The results showed that the best condition of color protecting were scalding 5min,boiling temperature 100?.2)To study the mixograph characteristics of mixed potato powder and flour(hereinafter referred to as the mixed powder).When the proportion of potato powder in mixed powder increased from 20% to 60%,the water absorption of powder increased from 79.6% to 101.7%,the dough development time is shortened from 2.4 min to 1.6min,the stability of dough time from 2.6 min shortened to 1.5min,the weakness increased from 459 FU to 918 FU.The results of ixograph characteristics shows:the amuout of water to be added should be increased with the increasing ratio of potato powder;the mixing time should be decareased with the increasing ratio of potato powder.3)The processing of baking crisps with green tea was studied.And the research included study of the best formula,operating key points in operation process and the best way of baking.Through single factor and multi factor orthogonal test for the optimum formula,the results are as follows: the protection of potato powder and flour is 40%,25% sugar,15%margarine,1.5%green tea powder;the amount of accessories: 1% salt,1% monosodium glutamate,1% sodium bicarbonate,0.4% ammonium hydrogen carbonate.We studied the operating key points in operation process including the order of addition--margarine and the rolling thickness.The result is: mix the powder and water first and then add the margarine;the formula rolling thickness is 1.5mm.To get the best way of baking,constant temperature baking,two-stage baking and three-stage baking were contrasted.Comparing the products,we choose the three-stage baking: the first stage of the surface fire at 140 ?,baking primer 150?,baking time 2.0min;the second stage of the surface fire at 170?,baking primer 150?,baking time 6.0min;third stages of surface fire and baking primer are both 130?,baking time 1.0min.4)It was studied that the effect of tea on baking crisps with green tea during storage time.It concludes hardness,fracturability,moisture content,peroxide value and acid value.The storage time of baking crisps and baking crisps with green tea is 4-5 weeks and 6-8 weeks respectively.The results are: the hardness of baking crisps and baking crisps with green tea reduced from 1643 g,1652g to 1600 g,1603g during the storage time;the fracturability of baking crisps and baking crisps with green tea increased from 655 g,660g to 724 g,758g;the moisture content of baking crisps and baking crisps with green tea increased from 3.54%,3.50% to 3.87%,3.84%.Before the sixth week,the peroxide value of baking crisps exceeds 0.25g/100 g,reaching 0.27g/100 g,and before the eighth week,the peroxide value of baking crisps with green tea exceeds 0.25g/100 g,reaching 0.26g/100g;the acid value of baking crisps and baking crisps with green tea exceed 5.0mg/g before the sixth week and eighth week,reaching 5.31mg/g and 5.01mg/g.The result shows that adding green tea powder can prolonge the storage time of baking crisps with green tea.5)It was studied that the character of baking crisps with green tea.Including sensory texture,physicochemical properties and comparison of products with several chips and biscuits,the results are: adding green tea powder to products enhances the sensory evaluation of products;it increased the hardness of products and reduce the fracturability;the moisture value of baking crisps is 0.04% higher than baking crisps;the peroxide value and acid value of baking crisps with green tea is 0.10g/100 g and 1.50mg/g,0.01g/100 g,0.08mg/g lower than baking crisps.The result shows that the green tea powder can have little influence on the moisture value,the peroxide value and acid value of baking crisps with green tea.Studying three aspects of the biscuits,and chips,we get the results that the baking crisps with green tea contains the highest content of the polyphenols and corase fiber by 0.21%,1.83%,yet,the fat content is less than half of the chips by 17.3%.6)The quality of baking crisps with green tea was studied.The product has the flavor of potatoes and the color of green tea.The structure is layering and tinkness is homogeneous.Moisture content is 3.19%;fat is 17.3%;sodium choride is1.2%;alkalinity(sodium carbonate)is 0.35 g / 100 g;acid value(fat)is 1.50 g/g;peroxide value(fat)is 0.10 g / 100 g;lead content is 0.052 mg/kg;total arsenic(arsenic)is 0.078 mg/kg;the total number of colonies is 130 cfu/g;coliform bacteria is less than 30 MPN / 100 g;mould is 20 cfu/g.The quality test results of above are up-to-standard.