阅读说明：本技术 一种羟丙基二淀粉磷酸酯的生产工艺 (Production process of hydroxypropyl distarch phosphate ) 是由 邵亚东 刘大伟 邬存斌 于 2020-06-19 设计创作，主要内容包括：本发明公开了一种羟丙基二淀粉磷酸酯的生产工艺,包括以下步骤：(1)将原淀粉和水混合配制成淀粉乳；(2)在步骤(1)所述淀粉乳中流加或滴加氢氧化钾溶液调节pH；(3)加入环氧丙烷,在40～45℃下,反应18～22h；(4)加入三偏磷酸钠或三氯氧磷反应3～8h,洗涤,脱水,干燥,即得所述羟丙基二淀粉磷酸酯。本发明所述羟丙基二淀粉磷酸酯的生产工艺利用氢氧化钾溶液调节反应体系的pH,不需要添加硫酸钠、氯化钠等盐作为膨胀抑制剂,解决了洗涤工序产生大量难处理高盐废水的生产技术难题。(The invention discloses a production process of hydroxypropyl distarch phosphate, which comprises the following steps: (1) mixing raw starch and water to prepare starch milk; (2) adding or dropping a potassium hydroxide solution into the starch milk obtained in the step (1) in a flowing manner to adjust the pH value; (3) adding propylene oxide, and reacting for 18-22 h at 40-45 ℃; (4) and adding sodium trimetaphosphate or phosphorus oxychloride to react for 3-8 h, washing, dehydrating and drying to obtain the hydroxypropyl distarch phosphate. The production process of the hydroxypropyl distarch phosphate utilizes the potassium hydroxide solution to adjust the pH value of a reaction system, does not need to add sodium sulfate, sodium chloride and other salts as swelling inhibitors, and solves the technical problem of production of a large amount of high-salt wastewater which is difficult to treat in a washing procedure.)

1. The production process of the hydroxypropyl distarch phosphate is characterized by comprising the following steps:

(1) mixing raw starch and water to prepare starch milk;

(2) adding or dropping a potassium hydroxide solution into the starch milk obtained in the step (1) in a flowing manner to adjust the pH value to 10-14;

(3) adding propylene oxide, and reacting for 18-22 h at 40-45 ℃;

(4) and adding sodium trimetaphosphate or phosphorus oxychloride to react for 3-8 h, washing, dehydrating and drying to obtain the hydroxypropyl distarch phosphate.

2. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (1), the mass concentration of the starch milk is 30-40%.

3. The process for producing hydroxypropyl distarch phosphate according to claim 1, wherein the potassium hydroxide solution is added in step (2) for a period of at least 3 hours.

4. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (2), the addition time of the potassium hydroxide solution is 3-5 h.

5. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (2), the mass concentration of the potassium hydroxide solution is 3-9%.

6. The production process of hydroxypropyl distarch phosphate according to claim 1, wherein in step (3), the amount of propylene oxide added is 3-10% by mass of the starch.

7. The production process of hydroxypropyl distarch phosphate as claimed in claim 1, wherein in step (4), the pH value after adding sodium trimetaphosphate or phosphorus oxychloride and reacting for 3-8 h is 3-5.

8. The process for producing hydroxypropyl distarch phosphate according to claim 1, wherein the native starch is at least one of tapioca starch, waxy corn starch and potato starch.

Technical Field

The invention relates to a preparation method of modified starch, in particular to a production process of hydroxypropyl distarch phosphate.

Background

Hydroxypropyl distarch phosphate is a product obtained by reacting raw material starch with crosslinking agents such as propylene oxide, sodium trimetaphosphate or phosphorus oxychloride and the like under an alkaline condition. The medium for producing the hydroxypropyl distarch phosphate comprises alcohol water solution, alcohol solution and water solution. The alcohol aqueous solution and the alcohol are used as media, the requirements on production equipment and reaction conditions are high, industrialization is not easy to realize, and potential safety hazards exist for factories due to storage of the alcohol. The alkaline catalyst commonly used in the production of hydroxypropyl distarch phosphate with water as the medium is sodium hydroxide. Sodium hydroxide solution with certain concentration is added to adjust the pH value of the reaction system, starch granules expand (are gelatinized after being seriously expanded) along with the rise of the pH value, the consistency of starch milk of the reaction system is increased, subsequent processes of starch reaction, washing, dehydration and the like are influenced, and the product quality is reduced. In order to prevent swelling and gelatinization of starch, a certain amount of salt (sodium sulfate or sodium chloride) is generally added as a swelling inhibitor, and the amount of the salt itself is adjusted according to the amount of propylene oxide added without participating in the reaction. Sodium sulfate is added under normal conditions to be 8-30% of the weight of starch. In the washing process, water which is 6-10 times of the weight of starch needs to be consumed for cleaning sodium sulfate, a large amount of high-salt water which is difficult to treat is generated, if the high-salt water is discharged into a sewage pipe, the high-salt water cannot be treated by an anaerobic process, only a high-cost aerobic aeration mode can be adopted for treatment, the treatment difficulty is high, and the equipment investment cost is high.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a production process of hydroxypropyl distarch phosphate.

In order to achieve the purpose, the invention adopts the technical scheme that: a production process of hydroxypropyl distarch phosphate comprises the following steps:

(1) mixing raw starch and water to prepare starch milk;

(2) adding or dropping a potassium hydroxide solution into the starch milk obtained in the step (1) in a flowing manner to adjust the pH value to 10-14;

(3) adding propylene oxide, and reacting for 18-22 h at 40-45 ℃;

(4) and adding sodium trimetaphosphate or phosphorus oxychloride to react for 3-8 h, washing, dehydrating and drying to obtain the hydroxypropyl distarch phosphate.

The production process of the hydroxypropyl distarch phosphate utilizes the mode of feeding or dripping the potassium hydroxide solution to adjust the pH of a reaction system, does not need to add salts such as sodium sulfate, sodium chloride and the like as swelling inhibitors, and solves the production technical problem that a large amount of high-salt wastewater which is difficult to treat is generated in a washing procedure.

In the step (1), the starch milk represents a mixture of raw starch and water.

Preferably, in the step (1), the mass concentration of the starch milk is 30-40%, and the reaction efficiency of the system and the stability of the reaction process can be effectively controlled by controlling the starch milk to be the concentration.

Preferably, in step (2), the potassium hydroxide solution is added for at least 3 hours.

Preferably, in the step (2), the adding time of the potassium hydroxide solution is 3-5 h. The inventors found that when the addition time of the potassium hydroxide solution is less than 3 hours, there is a certain degree of swelling, and when the addition time is extended to at least 3 hours, the swelling of starch can be suppressed, but the addition time is too long, which tends to result in low production efficiency.

Preferably, the mass concentration of the potassium hydroxide solution is 3-9%. The amount of potassium hydroxide to be added is determined by the pH of the reaction system, and in order to control the time of addition, it is preferable to use a potassium hydroxide solution having the above-mentioned mass concentration.

Preferably, in the step (4), the pH value after adding sodium trimetaphosphate or phosphorus oxychloride and reacting for 3-8 h is 3-5.

Preferably, in the step (3), the addition amount of the propylene oxide is 3-10% of the mass of the starch.

Preferably, the native starch is at least one of tapioca starch, waxy corn starch, and potato starch, but is not limited to the above species.

The invention has the beneficial effects that: the invention provides a production process of hydroxypropyl distarch phosphate, which adjusts the pH of a reaction system by using a mode of feeding or dripping a potassium hydroxide solution without adding salts such as sodium sulfate, sodium chloride and the like as swelling inhibitors, and solves the production technical problem that a large amount of high-salt wastewater which is difficult to treat is generated in a washing procedure. Meanwhile, the hydroxypropyl distarch phosphate product obtained by the preparation process has the characteristics of moderate viscosity, strong water retention capacity, acid and alkali resistance, mechanical processing resistance, smooth mouthfeel and the like, and conforms to the GB29931-2013 standard; the modified starch prepared by the process can be applied to foods such as yoghourt and sauce, and has the effects of thickening, water retention and freeze-thaw resistance.

Detailed Description

To better illustrate the objects, aspects and advantages of the present invention, the present invention will be further described with reference to specific examples.