Techniques of extracting rice protein

Abstract

The invention provides a process of extracting rice protein, which takes rice processing leftovers as raw material and comprises following steps: mixing acidic solution with pH being 0.5-3.5 with rice processing leftovers, the weight of acidic solution is 4-10 adjusted by sulfate times of that of rice processing leftovers, stirring evenly, adjusting pH with sulfate to 0.5-3.5, thermal insulating for 0.5-6 hours at 70-110 Deg. C, filtering to remove slag at 30-50 Deg. C, cooling filtering liquid to room temperature, adjusting pH to 3.5-4.5, stewing for 0.5-2 hours, pouring out clear liquid, spray drying, and getting said rice protein. The invention is characterize by dramatically improved rice protein taste compared with alkali extraction; increased safety because the acidic extraction hasno influence for amino acid damage; greatly reduced production cost compared with enzyme extraction, high purity of protein of more than 85wt%, and suitability for large scale production.

Description

(1) Technical field

[0001] The invention relates to a rice protein extraction process, which belongs to the field of food processing. (2) Background technology

[0002] At present, the methods for extracting rice protein from rice processing leftovers include alkaline extraction, enzymatic extraction, and enzymatic pretreatment alkaline extraction. The alkaline extraction process is relatively simple, but under high alkaline conditions, it can damage amino acids, affect the quality of rice protein, and even form toxic substances. The enzymatic extraction method can maintain the good quality of rice protein, but the processing cost is high, the extraction rate is average, and the purity of the obtained rice protein is not high. Alkaline extraction with enzymatic hydrolysis pretreatment has a higher extraction rate and higher purity of rice protein, but the process is more complicated, the processing cost is high, and the quality of rice protein is also affected by alkali ext...

Examples

Embodiment 1

[0017] Weigh the leftovers of early indica rice processed as monosodium glutamate (produced from Hangzhou monosodium glutamate factory in Zhejiang Province, the same below), with a dry weight of 1.0kg, add 6.0kg of pure water adjusted to pH 1.0 with sulfuric acid, stir evenly, and then add 10% Adjust the pH to 1.0 with mass concentration of sulfuric acid, heat and stir in a 90°C water bath for 3 hours, cool to 50°C, filter with a 100-mesh filter cloth to remove residue, cool the filtrate to room temperature, and adjust the pH of the filtrate with 10% mass concentration of sodium hydroxide to 4.0, let stand for 1.5 hours, pour off the clear liquid, and spray dry the solid to obtain 0.51kg of rice protein product with a purity of 86.7%.

Embodiment 2

[0019] Weigh the leftovers of early indica rice and process it as monosodium glutamate, the dry weight is 1.0kg, add 6.0kg of pure water that has been adjusted to pH 1.0 with sulfuric acid, stir evenly, and then adjust the pH to 1.0 with 10% mass concentration of sulfuric acid. Heat to 110°C with water vapor in a pressure vessel, keep it warm for 1 hour, stop heating, stir while cooling, reach 40°C, filter with 100-mesh filter cloth to remove residue, cool the filtrate to room temperature, and use 10% mass concentration of hydrogen Sodium oxide was used to adjust the pH of the filtrate to 4.0. Stand still for 1.5 hours, pour off the clear liquid, and spray-dry the solid to obtain 0.50 kg of rice protein product with a purity of 87.5%.

Embodiment 3

[0021] Weigh the leftovers of early indica rice and process it as monosodium glutamate, with a dry weight of 1.0kg, add 6.0kg of pure water that has been adjusted to pH 0.5 with sulfuric acid, stir evenly, and then adjust the pH to 0.5 with 10% mass concentration of sulfuric acid. Insulate and stir in a 90°C water bath for 3 hours, cool to 50°C, filter through a 100-mesh filter cloth to remove residue, cool the filtrate to room temperature, and adjust the pH of the filtrate to 4.0 with 10% mass concentration of sodium hydroxide. Stand still for 1.5 hours, pour off the clear liquid, and spray dry the solid to obtain 0.52 kg of rice protein product with a purity of 85.6%.

(1) Technical field

[0001] The invention relates to a rice protein extraction process, which belongs to the field of food processing. (2) Background technology

[0002] At present, the methods for extracting rice protein from rice processing leftovers include alkaline extraction, enzymatic extraction, and enzymatic pretreatment alkaline extraction. The alkaline extraction process is relatively simple, but under high alkaline conditions, it can damage amino acids, affect the quality of rice protein, and even form toxic substances. The enzymatic extraction method can maintain the good quality of rice protein, but the processing cost is high, the extraction rate is average, and the purity of the obtained rice protein is not high. Alkaline extraction with enzymatic hydrolysis pretreatment has a higher extraction rate and higher purity of rice protein, but the process is more complicated, the processing cost is high, and the quality of rice protein is also affected by alkali ext...

Examples

Embodiment 1

[0017] Weigh the leftovers of early indica rice processed as monosodium glutamate (produced from Hangzhou monosodium glutamate factory in Zhejiang Province, the same below), with a dry weight of 1.0kg, add 6.0kg of pure water adjusted to pH 1.0 with sulfuric acid, stir evenly, and then add 10% Adjust the pH to 1.0 with mass concentration of sulfuric acid, heat and stir in a 90°C water bath for 3 hours, cool to 50°C, filter with a 100-mesh filter cloth to remove residue, cool the filtrate to room temperature, and adjust the pH of the filtrate with 10% mass concentration of sodium hydroxide to 4.0, let stand for 1.5 hours, pour off the clear liquid, and spray dry the solid to obtain 0.51kg of rice protein product with a purity of 86.7%.

Embodiment 2

[0019] Weigh the leftovers of early indica rice and process it as monosodium glutamate, the dry weight is 1.0kg, add 6.0kg of pure water that has been adjusted to pH 1.0 with sulfuric acid, stir evenly, and then adjust the pH to 1.0 with 10% mass concentration of sulfuric acid. Heat to 110°C with water vapor in a pressure vessel, keep it warm for 1 hour, stop heating, stir while cooling, reach 40°C, filter with 100-mesh filter cloth to remove residue, cool the filtrate to room temperature, and use 10% mass concentration of hydrogen Sodium oxide was used to adjust the pH of the filtrate to 4.0. Stand still for 1.5 hours, pour off the clear liquid, and spray-dry the solid to obtain 0.50 kg of rice protein product with a purity of 87.5%.

Embodiment 3

[0021] Weigh the leftovers of early indica rice and process it as monosodium glutamate, with a dry weight of 1.0kg, add 6.0kg of pure water that has been adjusted to pH 0.5 with sulfuric acid, stir evenly, and then adjust the pH to 0.5 with 10% mass concentration of sulfuric acid. Insulate and stir in a 90°C water bath for 3 hours, cool to 50°C, filter through a 100-mesh filter cloth to remove residue, cool the filtrate to room temperature, and adjust the pH of the filtrate to 4.0 with 10% mass concentration of sodium hydroxide. Stand still for 1.5 hours, pour off the clear liquid, and spray dry the solid to obtain 0.52 kg of rice protein product with a purity of 85.6%.