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1、,制品,made products,ChiChengDeng ZhaoYingTing ZhangTingTing ChenZiHong ChenNi,rice,2/5/2023,Rice products,One.Introduction,Two.Processing technology,Rice products,Rice flour,Define of Rice flour:Rice flour is refers to take the rice as raw material,after soaking,cooking,layering process into strips,fi
2、liform rice products.,Ps:以大米为原料，经浸泡、蒸煮、压条等工序制成的条状、丝状米制品,Rice products,Differents Rice flour,?,?,?,?,?,?,How to make it?,Rice products,Background：Rice pasta has spread progressively over the recent years,especially because of the increasing number of consumers who are intolerant to gluten contained i
3、n wheat and other cereal grain based foods.Since it is gluten-free,alimentary rice pasta is used in dietary regimes especially for therapeutic purposes,and particularly for preventing and treating some diseases,such as celiac disease,which are caused by intolerance to food obtained from gluten conta
4、ining cereal grains.,Rice products,The overall flow of processing is as followed:.(补一下）,How to choose the raw materials and auxiliary raw materials(辅助原料）The principal raw material of rice noodles processing are rice,water and a few auxiliary raw materials.Its a fact that rice is the most important r
5、aw material among them,because its type and quality have a directly influence on the quality grade of rice noodles.In order to choose the high quality rice,we should pay attention to the characteristics of different rice.The gelation properties（胶凝特性）of starch(淀粉）is used in the processing of rice noo
6、dles.So the goal of adding auxiliary materials,such as,corn starch(玉米淀粉）and potato modified starch（马铃薯变性淀粉）are to improve gelation properties.,Corn starch is supposed to reduce broken bar rate(断条率），whiteness(洁白度）and ripeness.There are three reasons:1)corn starch which largely is made of starch and w
7、ater has high purity,so it has good whiteness,good toughness(韧性）.2)The particle of corn starch is bigger than that of rice,which contributes to low materialized temperature(物化温度低）。So rice noodle with corn starch evaporates the more ripe under the same conditions.3)Corn starch has more proportion of
8、amylose(直链淀粉），theretrogradation（回生）of starch gel（淀粉凝胶）is quicker.Its appending proportion(添加比例）is 2%5%.Adding mode:Stirring the rice noodles,adding corn starch and then mixing them.,The particle of potato modified starch is the biggest,gelatinization point(糊化温度）is the lowest.It will generate high vi
9、scosity(黏度）during its gelatinization and will form soft and lucid gel after cooling.After processing,potato modified starch has lower gelatinization point than the original rice,its viscosity is reduced and its difficult to being in retrogradation.Then what we can see is soft,lucid(透明的）,glossy（光泽的）,
10、smooth and chewy potato modified starch.Its appending proportion is 2%5%,which can also extend the shelf life and reduce rehydration time.Adding mode:Stirring the rice noodles,adding corn starch and then mixing them.Adding mode:Stirring the rice noodles,adding potato modified starch and then mixing
11、them.,How to pretreat the raw material?The pretreatment of the raw material includes washing the rice,wetting the rice and steeping the rice.,(一）wash the rice Washing is to remove the grain,dinas(砂石)and so on,which probably affect the production and quality.The main purposes of this processing are a
12、s followed:1)reduce broken bar rate,increase toughness。2）improve the color and increase transparency。3）enhance the continuity of production equipment。The standard of washing:sand-carrying capacity less than 0.02%,grain-carrying capacity less than 2 grain/kg.remaining of bran(留皮）no more than 15%.,(二）
13、wet the rice and steep the rice Wetting the rice is the main processing of dry-process(干法生产）,while steeping the rice is the main processing of wet-process（湿法生产）.The common purpose of wetting the rice and steeping the rice is to let the rice to absorb the water fully,soften and decompose its original
14、 hard tissue.Operation time is 212 hours and the standard of washing:water content is 28%30%after wetting the rice,40%45%after steeping the rice.If it is in the high temperature,in order to prevent the rice from turning sour,2%edible alcohol is used in it.,the main factors of pretreating the raw mat
15、erial 1.the factors which affect the washing quality 1)only wash but not grind(low grade)2)the flow is too much:impurity can not be washed away completely 2.the factors which affect the wetting and steeping quality1)covered water(着水量）：5cm over the rice2)the time of wetting the steeping:212 hours,acc
16、ording to the concrete situation,if it is in the high temperature,less time can be used.By the contrast,if it is in the low temperature,more time can be used.Of course,if the time were too short,broken bar rate(断条率）would be reduced.3.environmental temperature and humidity:High humidity and low tempe
17、rature lead to a fact that water evaporate slowly,so the time of wetting should be extended.Low humidity and high temperature lead to a fact that water evaporate quickly,so the covered water should be increased.,Step 3 crush,Definition:Crush is to overcome internal cohesion(凝聚力）of rice with machine
18、and it transfom it into powder.,Two methods,smash,grind,The purpose and effect of crush,1.The preparation for steaming it can shorten the time of steaming and incease the final production,2.Optimize（优化）the structure of starch Processed into rice vermicelli（粉条）,on the one hand is the destruction of n
19、ative structure,on the other hand is reassembled（重组）starch organizational structure.Only by crushing the rice,it can become a solid and compact structure3.make for the Gelatinized（糊化）of starch Destruction of the structure,it is easy for water to penetrate into the middle of the particles in favor of
20、 starch gelatinization.,Main factors of influence,1.moisture content of grain if moisture content of grain is low,it would be high production and low power consumption 2.the flow The flow into the crush machine will be a great influence for the crush.increasing the flow in a certain range,the produc
21、tion will be faster than the growth of energy consumption3.the size of sieve（筛子）Sive is the key to ensure the quality of the powder.usually the size is 0.6mm,Step 4 steaming,Definition:This is one of the important processes of rice production which is to gelatinize the powder of starch at a certain
22、temperature.,The purpose and effect of steaming,Steaming,is actually transform the rice starch into the colloid（胶体）in the relevant gelatinization temperature for processing into rice vermicelli.Only become colloid,rice starch becomes possible to glue.,Main factors of influence,1.the temperature The
23、temperature in the steaming pulp machine should be self to ensure the quality of vermicelli.If not,the vermicelli may be Wrinkled,overmature and insufficient cooked.2.the flow If the flow is too high,the vermicelli would be thick,and it may be insufficient cooked.if it is too low,the vermicelli woul
24、d be thin and it will affect production.3.water content and steaming timeIf the moisture content of materials is excessive,it will lead to deteriorateion（退化）of gelatinization.if the moisture content of materials is low and the stearming time is too long,it will cause the reduction of production.,Ric
25、e products,Vocabulary,the screw press machine 螺旋榨条机vermicelli.粉条the sieving plate 筛孔板starch 淀粉colloid 胶体extrude 挤压diameter 直径retrogradation 老化，回生evacuate 疏散 viscosity 粘度,Rice products,Squeeze material,cooling,loose wire,Rice products,the powder after cooking be extruded to a strip,for the next proce
26、dure,After high temperature steam and mixing，starch is heated and maturation as colloid。When colloid without external pressure,the internal structure of colloid is not very close,the purpose of the first pressing is to extrude a material with equal diameter,the same speed,close texture by putting pr
27、essure on colloid powder,Squeeze material,Rice products,Using the screw press machine（螺旋榨条机）with Strong extrusion,force the material tothrough the sieving plate（筛孔板）to become rice vermicelli.（粉条）,After steam mixing，the powder directly into feeding mouth of the head pressing machine,then into extrusi
28、on rob by the extrusion auger grab,and heated by steam indirectly，squeeze,rub,the role of the shear and other common to fully mix,further maturation。through the orifice plate extrusion article four materials.Head squeezed out of spices temperature reaches 70-90,ripening degree over 70%,Rice products
29、,Rice products,cooling,There are two different ways to cooling,one is air cooling,other is combination air cooling with natural cooling,Air cooling is the use of fan ventilation in a short time，which would not change the quality of rice vermicelli,The other way can result in retrogradation，so that i
30、t is applied only to powder production,not to rice production,Rice products,After the above three processes,the surface of vermicelli with a glue solution that viscosity is big，therefore need to evacuated timely,loose wire,Loose or coolthe vermicelli through the cold water tank,or cooling through th
31、e cold wind，then addloose wire by fluffer;Or loose wire by hand,Rice products,4、cook、cut off and shape up,After the previous steps,rice noodles have its initial shape.Then we need a second time cooking to improve the curing degree of rice noodles(熟化度),enhance the toughness(韧性)of the rice noodles,red
32、uce the phenomenon of paste soup(糊汤现象）when cooked and can make the rice noodles a shine bright out looking and low broken rate.,Control of moisture content in 45%62%,to make the starch gelatinization degree(淀粉糊化度)in 90%95%.,Cooking purpose,Cooking requirements,Rice products,4、cook、cut off and shape
33、up,Continuous cooking process,Batch cooking process,High pressure cooking process,Steam cooking,Two common cooking methods,Boild cooking,Rice products,The basic factors affecting the quality of cooking,A、cooking temperature Raise the temperature,higher than that of starch gelatinization temperature(
34、淀粉糊化温度),B、cooking time,4、cook、cut off and shape up,Rice products,cut off and shape up,In order to facilitate drying,packaging,measuring,transportation and consumption,rice noodles should be cut into a certain shape,4、cook、cut off and shape up,Straight strip shape(直条状成型)：Products are vertically press
35、ed and cut on main machine.Folding forming(折叠成型)：Folded the rice into loose block(松散块状)by hand,Loosely,good permeability,beautiful,novel style,easy to carry,etc,Formed method,Molding requirements,Rice products,5、Dry,The drying time of rice noodles should not be too short,general control in more than
36、 4 h.If the drying time is too short,the following phenomena will appear:a.Rice noodles with bubbles and affect the appearance,easy to break.b.Dehydration nonuniform,make the already dry parts brittle fracture(脆性破坏)and havent dry parts mildew(发霉).,Rice products,In order to improve the quality of ric
37、e noodle,prevent vermicelli(粉条)crisp(酥脆),discoloration(变色),spotted(长斑),the production should according to the rice drying principle and different environmental conditions,choose reasonable technology parameters.Long-term production experience shows that a high relative humidity of ambient air,low temperature can give the product a high quality after dry.,Low Temperature Long Time,5、Dry,Rice products,6、Packaging,Package in paper skin(纸箱)、in bags(袋装)、in cups(杯装),Marked the producer,product name,weight,production date etc on the packaging.,
