Process for preparing rice steamed sponge cake by using twin-screw extrusion powder

Abstract

The invention relates to a process for preparing a rice steamed sponge cake by using twin-screw extrusion powder. The process comprises the following steps: grinding rice by a grinder, and sieving to obtain rice flour; adjusting the temperature of three areas of the twin-screw extrusion bulking machine, the frequency of the main machine and the rotating speed of the screws, and performing extrusion gelatinization, drying, grinding and sieving to obtain rice extrusion powder; soaking, drying and grinding rice, and sieving with a 150-mesh sieve to obtain rice steamed sponge cake powder; and adding the rice extruded powder, the rice steamed sponge cake powder, the white sugar, the yeast and the water into a fermentation box in proportion, fermenting twice, steaming, demolding and cooling at room temperature. According to the process disclosed by the invention, after a proper amount of extruded powder is added into the rice flour, the network structure of the rice steamed sponge cake is obviously improved, pore aggregation is reduced, the tissue structure becomes better, the yeast gas production rate and the rice paste gas-holding property are improved, and the skin color, hardness and chewiness of the rice steamed sponge cake are improved to different extents.

Description

Technical Field

[0001] The present invention relates to a process for preparing rice sponge cake using twin-screw extrusion powder, belonging to the technical field of food processing. Background Art

[0002] Fermented rice products are loved by many diners due to their unique flavor, and fermented rice sponge cake has begun to appear in the catering industry. In the process of making rice sponge cake by traditional wet grinding, there is a possibility of microbial contamination, resulting in unstable quality of the made rice sponge cake. Moreover, the water content of the rice sponge cake is relatively high, and the finished rice sponge cake is not easy to store. Therefore, the industrialization of rice sponge cake has great obstacles. Since the gel structure formed by rice is weak, the quality of rice sponge cake made of pure rice flour is poor. Therefore, the quality improvement of rice sponge cake is the main content of the research on rice products.

[0003] At present, the quality improvement of rice sponge cake mainly focuses on three directions: raw materials, production process, and exogenous addition. There are relatively few articles on raw material research, more research on exogenous addition, and the leavening agent used in production is also a research hotspot.

[0004] Twin-screw extrusion is a food processing technology that integrates mixing, shearing, kneading, cooking, and compression. Compared with other food heat treatment processing methods, the nutritional quality of extruded products is relatively excellent. Twin-screw extrusion is widely used in the food industry. At present, more and more food enterprises have begun to apply twin-screw technology to production, and twin-screw extrusion technology is still in development. Therefore, finding the best twin-screw extrusion treatment process in the preparation process of rice sponge cake is a technical problem that needs to be solved urgently. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a process for preparing rice sponge cake using twin-screw extrusion powder.

[0006] The technical solution adopted by the present invention:

[0007] 1. A process for preparing rice sponge cake using twin-screw extrusion powder, comprising the following steps:

[0008] (1) Preparation of rice extrusion powder and rice sponge cake powder:

[0009] Preparation of rice extrusion powder: Rice is ground into powder by a pulverizer and passed through a 60-mesh sieve to obtain rice flour; the temperatures of the three zones of the twin-screw extrusion puffing machine, the main machine frequency, and the screw speed are adjusted, and extrusion gelatinization, drying, grinding, and passing through a 100-mesh sieve are carried out to obtain rice extrusion powder;

[0010] Preparation of rice sponge cake powder: Rice is soaked, dried, ground, and passed through a 150-mesh sieve to obtain rice sponge cake powder;

[0011] (2) Making of rice sponge cake:

[0012] Add rice extrusion powder, rice muffin powder, white sugar, yeast, and water to the fermentation box in proportion for primary fermentation. After the fermentation is completed, stir to exhaust gas, put it into a mold, and conduct secondary fermentation. After the secondary fermentation is completed, steam it with boiling water vapor. After steaming, demold and cool at room temperature.

[0013] In step (1) when preparing the rice extrusion powder, the parameters of the twin-screw extrusion expander are as follows: the temperature of the three zones is 90 - 140 °C, the main machine frequency is 13 - 23 Hz, and the moisture content of the material is 20 - 30%.

[0014] In step (1) when preparing the rice extrusion powder, the parameters of the twin-screw extrusion expander are as follows: the temperature of the three zones is 130 °C, the main machine frequency is 17 Hz, and the moisture content of the material is 22%.

[0015] In step (2), the raw material dosages for the rice muffin are 5.0 g of rice extrusion powder, 95.0 g of rice muffin powder, 20 g of white sugar, 0.80 g of yeast, and 100.0 g of water.

[0016] In step (2), the conditions for primary fermentation are 37 °C, 80% humidity, and fermentation for 80 min; the conditions for secondary fermentation are 37 °C, 80% humidity, and fermentation for 60 min.

[0017] In step (2), the time for steaming with boiling water vapor is 15 min.

[0018] Advantages of the present invention

[0019] (1) In the present invention, rice powder is prepared by extrusion treatment, and rice muffins are prepared by adding extrusion powder to explore the modification of rice powder by extrusion treatment and the influence and action principle of the addition of extrusion powder on the gel properties of rice. This provides a theoretical basis for the quality improvement of gluten-free rice muffins.

[0020] (2) In the present invention, extrusion powder is prepared from rice powder. Taking the specific volume reflecting the gel structure and tissue structure of the rice muffin as the optimization index, and at the same time taking the water absorption index of the extrusion powder as the reference optimization index, the optimal process parameters of the extrusion powder are obtained through single-factor and orthogonal experiments: the temperature of the three zones is 130 °C, the main machine frequency is 17 Hz, and the moisture content of the material is 22%. The highest specific volume of the rice muffin obtained by adding 5.0% extrusion powder to the rice muffin powder is 1.97 g / ml.

[0021] (3) The network structure of the rice muffin prepared by the process of the present invention is significantly improved, the aggregation of pores is reduced, the tissue structure is improved, the gas production of yeast and the gas retention property of the rice paste are both improved. In addition, the skin color, hardness, and chewiness of the rice muffin are improved to varying degrees. Description of the drawings

[0022] Figure 1 Effect of the temperature of the three zones of the extruder on the apparent morphology of the extrudate;

[0023] Figure 2Effect of the temperature of three zones of the extruder on the puffiness of the extrudate;

[0024] Figure 3 Effect of the temperature of three zones of the extruder on the gelatinization degree of the extruded powder;

[0025] Figure 4 Effect of the temperature of three zones of the extruder on the hydration characteristics of the extruded powder;

[0026] Figure 5 Effect of the main machine frequency of the extruder on the apparent morphology of the extrudate;

[0027] Figure 6 Effect of the main machine frequency of the extruder on the puffiness of the extrudate;

[0028] Figure 7 Effect of the main machine frequency of the extruder on the gelatinization degree of the extruded powder;

[0029] Figure 8 Effect of the main machine frequency of the extruder on the hydration characteristics of the extruded powder;

[0030] Figure 9 Effect of the material moisture of the extruder on the morphology of the extrudate;

[0031] Figure 10 Effect of the material moisture of the extruder on the puffiness of the extrudate;

[0032] Figure 11 Effect of the material moisture of the extruder on the gelatinization degree of the extruded powder;

[0033] Figure 12 Effect of the material moisture of the extruder on the hydration characteristics of the extruded powder. Detailed implementation manners

[0034] The following examples will describe the technical solutions of the present invention in detail.

[0035] In the following examples, unless otherwise specified, the materials, reagents, etc. used are all conventional biochemical reagents and can be obtained from commercial channels, and the methods used are all conventional methods.

[0036] Example 1. Preparation of rice sponge cake

[0037] 1.1 Rice flour making

[0038] (1) Preparation of extruded powder: Grind rice into powder, pass through a 60-mesh sieve to obtain rice flour, with the material moisture content being 22%, adjust the temperature of the three zones of the extruder to 130 °C and the main machine frequency to 17 Hz for extrusion, then dry at 50 °C for 5 h, grind the powder with a pulverizer, and pass through a 100-mesh sieve to obtain rice extruded powder, and store it at 4 °C for standby.

[0039] (2) Preparation of rice cake powder: Soak rice for 4 h, dry it at 35 °C for 5 h, grind it into powder and sieve it through a 150-mesh sieve to obtain rice cake powder, which is stored at 4 °C for later use.

[0040] 1.2 Production of rice cakes

[0041] Measure 5.0 g of extruded powder, 95.0 g of rice cake powder, 20 g of white sugar, 0.80 g of yeast, and 100.0 g of water. Ferment at 37 °C and relative humidity of 80% for 80 min. After fermentation, stir to exhaust air. Take 60 g of rice paste and put it into a square mold for about 10 min, and then ferment it for 60 min at 37 °C and relative humidity of 80%. After fermentation, steam it with boiling water for 15 min. After steaming, demold it and cool it at room temperature to obtain rice cakes.

[0042] Example 2. Influence of the three-zone temperature of the extruder on the quality of extruded powder and rice cakes

[0043] Fix the moisture content of the material (rice flour) at 26%, the screw speed at 15 Hz, and the feeding frequency at 9 Hz. Set the three-zone temperature of the extruder at 90, 100, 110, 120, 130, and 140 °C. After drying the extrudate at 50 °C, analyze it to explore the influence of the three-zone temperature on the quality of the extruded powder and the rice cake.

[0044] 2.1 Influence of the three-zone temperature on the apparent morphology of the extrudate

[0045] The apparent morphology of the extrudate is as Figure 1 shown. It can be seen that with other conditions fixed, when the three-zone temperature is below 110 °C, there are no obvious holes in the extrudate, and the extrudate is gelatinized without being expanded. The extrudate starts to expand at 110 °C, and pores begin to appear in the extrudate. As the three-zone temperature increases, the internal voids of the extrudate gradually become larger, and there are more and more large holes inside.

[0046] 2.2 Influence of the three-zone temperature on the expansion degree of the extrudate

[0047] Measurement of the expansion degree of the extrudate: Randomly select the extrudate, measure its diameter with a vernier caliper 30 times, calculate the average value, and the ratio of the cross-sectional area of the expanded product to the area of the die hole is the expansion degree.

[0048] The test results are as Figure 2 shown. From the morphology of the extrudate, with other conditions fixed, when the three-zone temperature is below 110 °C, there are no obvious holes in the extrudate, and the extrudate is gelatinized without being expanded; as the three-zone temperature increases, the internal voids of the extrudate gradually become larger, and there are more and more large holes inside. When the temperature is between 100 - 130 °C, the expansion degree of the extrudate is positively correlated with the temperature and reaches the maximum value when the three-zone temperature is 133 °C, and then starts to decline. Note: Different lowercase letters indicate significant differences (p < 0.05), the same below.

[0049] 2.3 Influence of the temperature in three zones on the gelatinization degree of extruded powder

[0050] Determination of the gelatinization degree of extruded powder: Take two 250 mL conical flasks V 1 and V 2 , and put 1.000 g of the extruded powder sample into each respectively. The conical flask (V 0 ) serves as a blank without adding the sample. Add 50 mL of distilled water to each of the conical flasks V 0 , V 1 , and V 2 , and shake well. Bring the conical flask V 1 to a gentle boil over low heat for 20 min to completely gelatinize it. After the gelatinization is completed, quickly cool the conical flask V 1 to room temperature. Add 2 mL of glucoamylase to each of the conical flasks V 0 , V 1 , and V 2 , shake well, place them in a constant temperature water bath at 50 °C, keep them warm for 1 h and then take them out, and then add 2 mL of 1 mol / L hydrochloric acid to terminate the reaction. Make the volume up to 100 mL respectively and filter for standby.

[0051] Take 10 mL of the filtrate into three 250 mL iodine flasks respectively, add 10 mL of 0.05 mol / L iodine solution and 18 mL of 0.1 mol / L sodium hydroxide solution, seal and place them in the dark for reaction for 15 min. After the dark reaction is completed, add 2 mL of 10% sulfuric acid to each, and then titrate with 0.05 mol / L sodium thiosulfate solution until it turns colorless, and record the volume (mL) of sodium thiosulfate used.

[0052] Gelatinization degree = [(V 0 −V 2 ) / (V 0 −V 1 )] × 100%

[0053] V 0 : The volume of sodium thiosulfate consumed in titrating the blank; V 1 : The volume of sodium thiosulfate consumed in titrating the completely gelatinized sample; V 2 : The volume of sodium thiosulfate consumed in titrating the sample.

[0054] The test results are as Figure 3 shown. Under the condition that other extrusion conditions remain unchanged, with the increase of the temperature in the three zones, the gelatinization degree of the extruded rice powder increases with the increase of the temperature in the three zones, showing a positive correlation.

[0055] 2.4 Influence of the temperature in three zones on the hydration properties of extruded powder

[0056] Determination of water solubility index and water absorption index: Place 0.8 g (dry basis) of the sample and 25 mL of distilled water in a centrifuge tube, mix evenly, place in a water bath at 30 °C for 30 min, take it out every 10 min and vortex for 5 s, and centrifuge at 4500 r / min for 10 min after the water bath ends. Collect the supernatant and dry it to a constant weight at 105 °C, and weigh the weight of the residue (W 1 ) and the dry weight of the supernatant (W 2 ). The water absorption index (WAI), water solubility index (WS), and swelling potential (SP) are calculated according to the following formulas.

[0057]

[0058] In the formula: W 0 is the dry weight of the sample, water absorption index (WAI), water solubility index (WS), and swelling potential (SP).

[0059] The test results are as Figure 4 shown. When other extrusion conditions remain unchanged, the water absorption index (WAI) of the extruded rice flour increases uniformly with the increase of the temperature in the three zones; the water solubility (WS) and swelling potential (SP) increase slowly with the increase of the temperature in the three zones at 90 - 120 °C. When the temperature in the three zones is 130 °C, the water solubility increases more, and its highest water solubility is about 20.15%. The change trends of water solubility and swelling potential are similar.

[0060] 2.5 Effect of the temperature in the three zones on the color of the extruded powder

[0061] Determination of the color difference of the extruded powder: Crush the sample to be tested with a high-speed universal grinder, pass it through a 100-mesh sieve, and then use a color difference meter to measure the color of the powder. Measure the parameters L*, a*, b*.

[0062] The test results are shown in Table 1. It can be seen from the experimental data that with the increase of temperature, the brightness L* of the extruded powder generally shows a trend of first increasing and then decreasing; its a* is negative, and the extruded powder is generally greenish. With the increase of the temperature in the three zones, the a* value of the extruded powder decreases significantly, and the green color weakens; b* is positive, and the extruded powder is generally yellowish, and the change of b* of the extruded powder is not significant. The color difference △E of the extruded powder between 100 - 140 °C shows a trend of first decreasing and then increasing with the increase of the temperature in the three zones; the whiteness (WI) value of the extruded powder does not change significantly between 100 - 140 °C with the increase of the temperature in the three zones.

[0063] Table 1 Effect of the temperature in the three zones on the color of the extruded powder

[0064]

[0065] 2.6 Effect of the temperature in the three zones on the specific volume of rice sponge cake

[0066] The specific volume of rice sponge cake is calculated according to the following formula: P = V / m

[0067] In the formula: P is the specific volume of rice sponge cake, mL / g; V is the volume of rice sponge cake, mL; m is the mass of rice sponge cake, g.

[0068] The test results are shown in Table 2. It can be seen from the experimental data that with the increase of the temperature in the three zones, the specific volume of the rice sponge cake added with 5% extrusion powder shows a trend of first increasing and then decreasing, and the maximum specific volume of the rice sponge cake can reach 2 mL / g.

[0069] Table 2 Influence of the temperature in the three zones on the specific volume of rice sponge cake

[0070]

[0071] 2.7 Influence of the temperature in the three zones on the texture of rice sponge cake

[0072] Measurement of the texture of rice sponge cake: Cool the cooked rice sponge cake for 1 hour, cut it into slices with a thickness of 1.5 cm, and perform a full texture measurement using a TA.XTPlus texture analyzer.

[0073] The test results are shown in Table 3. It can be seen from the experimental data that the hardness and chewiness of the rice sponge cake added with 5% extrusion powder show a trend of first increasing and then decreasing with the increase of the temperature in the three zones, and their change trends are similar to the change of the specific volume of the rice sponge cake. With the increase of the temperature in the three zones, the cohesiveness and elasticity of the rice sponge cake have no significant changes.

[0074] Table 3 Influence of the temperature in the three zones on the texture of rice sponge cake

[0075]

[0076] Based on the comprehensive above indicators, when the temperature in the three zones is 110, 120, and 130 °C, the extrudate expands, its gelatinization degree is relatively large, the water absorption index of the extrusion powder is relatively high and the water solubility has significant changes, and the specific volume of the produced rice sponge cake is relatively large.

[0077] Example 3. Influence of the main engine frequency on the quality of extrusion powder and rice sponge cake

[0078] Fix the moisture content of the material before extrusion at 26%, the temperature in the three zones at 120 °C, and the feeding frequency at 9 Hz. Set the main engine frequencies of the extruder to 13, 15, 17, 19, 21, and 23 Hz respectively to explore the influence of the main engine frequency on the quality of extrusion powder and sponge cake. The detection method is the same as that in Example 2.

[0079] 3.1 Influence of the main engine frequency on the apparent morphology of the extrudate

[0080] The apparent morphology of the extrudate is as Figure 5As shown, when other conditions are fixed and the main machine frequency is between 13 - 23 Hz, pores appear in the extrudate, and different degrees of puffing occur. When the main machine frequency is relatively low, the pores formed in the extrudate are larger. As the main machine frequency increases, the pores in the extrudate gradually become smaller, and the diameter of the extrudate also gradually increases.

[0081] 3.2 Influence of Main Machine Frequency on the Puffing Degree of Extrudate

[0082] The test results are as Figure 6 shown. As the main machine frequency increases, the puffing degree of the extrudate increases significantly, and the increase is relatively large when the frequency increases from 17 - 21 Hz.

[0083] 3.3 Influence of Main Machine Frequency on the Gelatinization Degree of Extruded Flour

[0084] The test results are as Figure 7 shown. With other conditions fixed, as the main machine frequency increases, the gelatinization degree of the extruded flour shows a trend of first increasing and then decreasing, and the gelatinization degree reaches the peak at 20 Hz, with the maximum value being approximately 74.60%.

[0085] 3.4 Influence of Main Machine Frequency on the Hydration Characteristics of Extruded Flour

[0086] The test results are as Figure 8 shown. With other conditions fixed, the water absorption index (WSI) of the extruded flour increases as the main machine frequency increases. Compared with the change in temperature, the change in the main machine frequency has a smaller impact on the water absorption index of the extruded flour. As the main machine frequency increases, the water solubility (WS) and swelling potential (SP) of the extruded flour show a gradually increasing trend.

[0087] 3.5 Influence of Main Machine Frequency on the Color of Extruded Flour

[0088] The test results are shown in Table 4. From the experimental data, it can be seen that as the main machine frequency increases, the L* value of the extruded flour generally shows a gradually increasing trend. The a* value is negative, indicating that the color of the extruded flour is slightly green, and the a* value gradually increases as the main machine frequency increases. The change in the b* value is not significant, and the change in △E is similar to that of the b* value. The whiteness (WI) generally shows an increasing trend as the main machine frequency increases, but the increase amplitude is small.

[0089] Table 4 Influence of Main Machine Frequency on the Color of Extruded Flour

[0090]

[0091] 3.6 Influence of Main Machine Frequency on the Specific Volume of Rice Cakes

[0092] The test results are shown in Table 5. As the main machine frequency increases, the specific volume of the rice cakes made with 5% extruded flour shows a trend of first increasing and then decreasing, and the specific volume of the rice cakes corresponding to 17 Hz is the largest.

[0093] Table 5 Influence of Host Frequency on Specific Volume of Rice Sponge Cake

[0094]

[0095] 3.7 Influence of Host Frequency on Texture of Rice Sponge Cake

[0096] The test results are shown in Table 5. As the host frequency increases, the hardness of the rice sponge cake first increases and then decreases, and the change trend is similar to that of chewiness. When the host frequency is 17 Hz, the hardness of the rice sponge cake is the largest and the chewiness is the strongest. As the host frequency increases, the cohesiveness and elasticity of the rice sponge cake do not change significantly. This shows that the cohesiveness and elasticity of the rice sponge cake with 5% extrusion powder are not affected by the frequency change during the extrusion process.

[0097] Table 6 Influence of Host Frequency on Texture of Rice Sponge Cake

[0098]

[0099] From the analysis of the above indexes, it can be seen that when the host frequencies are 15, 17, and 19 Hz, the gelatinization degrees of the extrusion powder are significantly different. The extrusion powder is whiter in color, has a higher water absorption index, lower water solubility, and the rice sponge cake made has a larger specific volume.

[0100] Example 4. Influence of Material Moisture on Quality of Extrusion Powder and Rice Sponge Cake

[0101] When the temperature of the three zones is fixed at 120 °C, the feeding frequency is 9 Hz, and the host frequency is 17 Hz, and the material moisture is adjusted to 20%, 22%, 24%, 26%, 28%, and 30% respectively, the influence of material moisture on the quality of extrusion powder and sponge cake is explored. The detection method is the same as that in Example 2.

[0102] 4.1 Influence of Material Moisture on Extrudate Morphology

[0103] The apparent morphology of the extrudate is as Figure 9 shown. When other extrusion conditions remain unchanged, as the material moisture increases, all the extrudates expand, and the pores of the extrudates gradually become larger with the increase of moisture. Among them, when the material moisture is 20 - 26%, the pores of the extrudates after expansion are relatively uniform.

[0104] 4.2 Influence of Material Moisture on Degree of Expansion of Extrudate

[0105] The test results are as Figure 10 shown. When other extrusion conditions are fixed and unchanged, as the material moisture increases, all the extrudates expand, and the pores of the extrudates gradually become larger with the increase of moisture. Among them, when the material moisture is 20 - 26%, the pores of the extrudates after expansion are relatively uniform.

[0106] 4.3 Influence of Material Moisture on Gelatinization Degree of Extrusion Powder

[0107] The test results are as Figure 11 shown. The gelatinization degree of the extruded powder first decreases and then increases with the increase of the material moisture content. When the material moisture content is 20%, the gelatinization degree of the extruded powder is the highest, about 80.20%; when the material moisture content is 26%, the gelatinization degree of the extruded powder is the lowest, about 72.45%.

[0108] 4.4 Effect of material moisture on the hydration properties of extruded powder

[0109] The test results are as Figure 12 shown. When the material moisture content is 20 - 22%, the water absorption index (WSI) of the extrudate is relatively high. When the material moisture content increases to 24%, the water absorption index (WSI) of the extruded powder decreases significantly. When the material moisture content is 24 - 30%, the water absorption index of the extruded powder shows a slow downward trend with the increase of the material moisture content. Generally speaking, the water absorption index (WAI) of the extruded powder decreases with the increase of the material moisture content.

[0110] 4.5 Effect of material moisture on the color of extruded powder

[0111] The test results are shown in Table 7. The brightness L* value of the extruded powder first increases and then decreases with the increase of the material moisture content, reaching the highest when the material moisture content is 26%. The a* value of the extruded powder is negative, showing a general greenish color, with a similar change trend to the L* value. The whiteness value also shows this change pattern, and the change trends of the L* and a* values are opposite to the change trend of the gelatinization degree of the above-mentioned extruded powder. The b* value of the extruded powder is positive, and the color of the extruded powder is yellowish.

[0112] Table 7 Effect of material moisture on the color of extruded powder

[0113]

[0114] 4.6 Effect of material moisture on the specific volume of rice cakes

[0115] The test results are shown in Table 8. The specific volume of the rice cakes made with 5% extruded powder gradually decreases with the increase of the material moisture content (22 - 30%).

[0116] Table 8 Effect of material moisture on the specific volume of rice cakes

[0117]

[0118] 4.7 Effect of material moisture on the texture of rice cakes

[0119] The detection results are shown in Table 9. It can be seen from the experimental data that the hardness of the rice sponge cake with 5% extruded powder first increases and then decreases with the increase of the material moisture content (22 - 30%). The change trend of the chewiness of the rice sponge cake is similar to that of the hardness. The elasticity of the rice sponge cake changes slightly with the increase of the material moisture content.

[0120] Table 9 Effect of Material Moisture Content on the Texture of Rice Sponge Cake

[0121]

[0122] From the above analysis, it can be seen that when the moisture content of the extruded material is 22%, 24%, and 26%, the water absorption index of the extruded powder is relatively high, and the change gradient of water solubility is relatively large. The gelatinization degree of the extruded powder changes significantly, and the specific volume of the rice sponge cake produced is relatively large.

[0123] Example 5. Optimization of the Extrusion Process Affecting the Quality of Rice Sponge Cake

[0124] According to the results of the above single-factor experiments, select the best range of extrusion process parameters, and optimize the process parameters with three factors: the temperature of the three zones, the main machine frequency, and the material moisture content.

[0125] 5.1 Design an orthogonal experiment with the water absorption index (WAI) of the extruded powder

[0126] Taking the WAI as the evaluation index, the influence degrees of the three factors of the temperature of the three zones, the main machine frequency, and the feed moisture content are in the order of the temperature of the three zones, the main machine frequency, and the material moisture content. According to the variance results, the temperature of the three zones and the main machine frequency have extremely significant effects on the water absorption index (WAI) of the extruded powder, and the material moisture content has a significant effect on the water absorption index of the extruded powder. According to the range results, the best process parameters are A3B3C1, that is, the temperature of the three zones is 130 °C, the main machine frequency is 19 Hz, and the material moisture content is 22%.

[0127] 5.2 Design an orthogonal experiment with the specific volume of the rice sponge cake as the evaluation index

[0128] Taking the specific volume of the rice sponge cake made with 5% extruded powder as the evaluation index, the influence degrees of the three factors of the temperature of the three zones, the main machine frequency, and the feed moisture content are in the order of the temperature of the three zones, the main machine frequency, and the material moisture content. Among them, according to the variance results, the temperature of the three zones and the main machine frequency have extremely significant effects on the specific volume of the rice sponge cake made with the extruded powder, and the material moisture content has a significant effect on the specific volume of the rice sponge cake made with the extruded powder. According to the range results, the best process parameters are analyzed, that is, the temperature of the three zones is 130 °C, the main machine frequency is 17 Hz, and the material moisture content is 22%.

[0129] When rice flour is extruded by a twin-screw extruder, it is subjected to high temperature and shear forces. The extruded rice flour undergoes gelatinization. Different extrusion process conditions have different effects on the puffing degree, hydration characteristics, gelatinization degree, and color difference of the extrudate, and have an impact on the quality of the rice sponge cake when added to it.

[0130] (1) Taking the water absorption index (WAI) as the evaluation index, the order of the influence of the three factors of the three-zone temperature, the main machine frequency, and the feed moisture is: three-zone temperature > main machine frequency > material moisture. Taking the specific volume of the rice sponge cake made with 5% extrusion powder added as the evaluation index, the order of the influence of the three factors of the three-zone temperature, the main machine frequency, and the feed moisture is: three-zone temperature > main machine frequency > material moisture.

[0131] (2) The optimal extrusion process parameters for adding the double-screw extrusion-treated rice flour to the rice sponge cake are: the three-zone temperature is 130 °C, the main machine frequency is 17 Hz, and the material moisture is 22%.

Claims

1. A process for preparing steamed rice cake by using twin-screw extruder powder, characterized in that: The following steps are involved: (1) Preparation of rice extruded powder and rice steamed cake powder: Preparation of rice extruded powder: grind rice with a crusher, pass through a 60-mesh sieve to obtain rice powder; adjust the temperature of the three zones of the twin-screw extruder, the main machine frequency, and the screw speed, extrude gelatinization, dry, grind, and pass through a 100-mesh sieve to obtain rice extruded powder; Preparation of rice steamed cake powder: soaking rice, drying, grinding, and passing through a 150-mesh sieve to obtain rice steamed cake powder; (2) Making steamed rice cake: Add rice extruded powder, rice cake powder, sugar, yeast and water in proportion to the fermentation box for primary fermentation; after the fermentation is completed, stir to exhaust and put into the mold for secondary fermentation; after the secondary fermentation is completed, steam with boiling water, demould after steaming, and cool at room temperature.

2. The process according to claim 1, characterized in that In step (1), the parameters of the twin-screw extruder during the preparation of rice extruded powder are as follows: the temperature of the three zones is 90-140° C., the main engine frequency is 13-23 Hz, and the material moisture is 20-30%.

3. The process according to claim 1, characterized in that Step (1) The parameters of the twin-screw extruder during the preparation of rice extruded powder are: three-zone temperature of 130° C., main engine frequency of 17 Hz, and material moisture of 22%.

4. The process according to claim 1, characterized in that The raw material dosage of the steamed rice cake in step (2) is 5.0g of rice extruded powder, 95.0g of rice steamed cake powder, 20g of white sugar, 0.80g of yeast and 100.0g of water.

5. The process according to claim 1, characterized in that In step (2), the primary fermentation conditions are 37° C., 80% humidity, and fermentation for 80 min; the secondary fermentation conditions are 37° C., 80% humidity, and fermentation for 60 min.

6. The process according to claim 1, characterized in that The boiling water steaming time in step (2) is 15 min.

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