CN104872582A - Technology for preparing potato flour by electrothermal forced air drying method - Google Patents

Abstract

The invention provides a process for preparing raw potato powder by an electric blast drying method, which belongs to the technical field of potato processing. The present invention uses fresh potato tubers as raw materials, after cleaning, peeling and cutting into pieces, soaking and protecting the color with the color protecting solution first, taking it out and draining, putting it into an electric blast drying box for electric blast drying and dehydration; then crushing, Sieve and pack to get raw potato powder. The invention can keep the color, aroma and taste of the potato to the greatest extent and obtain a high-quality final product by controlling the temperature of the electric blast drying and dehydration below the potato protein denaturation temperature and the starch gelatinization temperature. Therefore, the raw potato flour prepared has biologically active protein, and protein cross-linking can occur during the kneading process to form a gluten network structure, which solves the processing performance problem of potato dough used as noodles and steamed bread processing, and has great significance for promoting the potato staple food. Significance.

Description

Process for preparing raw potato powder by electric blast drying

technical field

The invention relates to a process for preparing raw potato powder, in particular to a process for preparing raw potato powder by an electric blast drying method, and belongs to the technical field of potato processing.

Background technique

Potato is an important grain and economic crop in my country, and its planting area and output both rank first in the world. In 2013, the total output of potatoes in my country exceeded 80 million tons, making it the fourth largest food crop after rice, corn and wheat. In January 2015, the No. 1 document of the Central Committee and the Ministry of Agriculture adopted the strategic development of potato as a staple food, which will have more important significance in ensuring national food security and promoting national social and economic development.

Potato staple food is an ideal choice: fresh potato tubers consist of about 80% water and 20% dry matter, and contain about 18 g carbohydrates and 2 g protein per 100 g potato tubers. Potato tubers are rich in vitamin C, vitamin E and B vitamins, as well as mineral elements such as potassium and magnesium. In addition, they also contain other important biologically active small molecules, most of which are phytonutrients, including polyphenols, flavonols, and anthocyanins. Carotenoids, phenolic acids, carotenoids, polyamines, glycoalkaloids, tocopherols, convolvulus, sesquiterpenes, etc., the carotenoids contained are not found in staple foods such as wheat and rice. Potatoes have low fat content, which is beneficial to inhibit weight gain and prevent obesity; high-quality protein, comprehensive amino acid composition, and lysine content far exceed wheat and rice protein, which can just make up for the defect of grain protein (lack of lysine). Influenced by our country's traditional food culture, the main forms of potato staple food consumption advocated at this stage include potato noodles, steamed buns and other staple food forms.

Potato powder is a kind of dehydrated potato products. As a semi-finished raw material, it almost maintains the full nutrition and flavor of potatoes, and is convenient for storage. It is suitable for adding and mixing in various foods. It is ideal for making potato steamed bread and noodles. raw material. However, the existing potato flour currently on the market is made from fresh potatoes, which are obtained through high-temperature drying and dehydration through processes such as cleaning, peeling, selection, slicing, rinsing, precooking, cooling, steaming, mashing, etc. Fine granules, flakes or powder products. After repeated high-temperature treatment, potato flour has become a mature whole powder. Its main component, potato starch, has been gelatinized and the protein has been denatured. Adding this potato "cooked" whole flour to flour will have adverse effects on the gluten structure, mechanical properties and mechanical properties of wheat dough. The current experimental results show (http://www.guancha.cn/Science/2015_02_04_308594.shtml), the amount of potato flour in steamed bread can reach 40%, and the amount of potato flour in noodles can reach 35%. Continue Increasing the amount of potato flour added will lead to problems such as easy breaking of noodles, difficulty in forming steamed buns, and difficulty in steaming. The actual situation may be worse. Therefore, the amount of potato (cooked) whole powder added to flour to make noodles and steamed buns is limited. Moreover, the temperature-sensitive vitamins in potato (cooked) whole powder processed under high temperature are seriously damaged, which has a certain impact on the nutritional quality of potatoes.

The denaturation temperature of potato protein and the gelatinization temperature of starch are both about 70°C. The low-temperature drying method is used to ensure the biological activity of the protein and the gelatinization of the starch. The preparation of raw potato powder is applied to the production of noodles and steamed bread, which is very important for improving the processing performance of dough. effect.

Contents of the invention

The purpose of the present invention is to provide a process for preparing raw potato powder by electric blast drying method based on the defects of traditional potato powder in the production of noodles and steamed buns, so as to meet the application of potatoes in noodles, steamed buns and other foods, and to promote The staple food of Chinese potatoes.

The process of preparing raw potato powder by the electric blast drying method of the present invention is to wash, peel and cut the fresh potato tubers into pieces, soak them in the color protection solution, take them out and drain them, and then put them into an electric blast drying box. Carry out electric blast drying and dehydration; then crush, sieve, and pack to get raw potato powder.

Potato raw materials include all varieties of potatoes, including regular-flesh potato varieties (common white-flesh or yellow-flesh potato varieties), and colored-flesh potato varieties (colored potato varieties such as purple flesh and red flesh). Potato raw materials require potato varieties with few and extremely shallow bud eyes, high solid content, and high cysteine content to be the preferred varieties. The dicing is cutting the potatoes into slices, dices or strips.

The color protection by soaking in the color protection solution is to soak the cut potatoes in the color protection solution for 10-30 min. Wherein the color protecting solution is at least one of vitamin C, citric acid and sodium bisulfite solution with a concentration of 1-3 g/L.

The temperature of the electric blast drying and dehydration is 40°C-60°C, and the moisture content of the potatoes after drying and dehydration is 5%-15%.

After crushing and sieving, the particle size of the raw potato powder product is 80-140 mesh.

The invention can keep the color, aroma and taste of the potato to the greatest extent and obtain a high-quality final product by controlling the temperature of the electric blast drying and dehydration below the potato protein denaturation temperature and the starch gelatinization temperature. Therefore, the raw potato flour prepared has biologically active protein, and protein cross-linking can occur during the kneading process to form a gluten network structure, which solves the processing performance problem of potato dough used as noodles and steamed bread processing, and has great significance for promoting the potato staple food. Significance.

Detailed ways

The preparation of raw potato powder by the electric blast drying method of the present invention will be further described below through specific examples.

Embodiment one

Potato raw materials: fresh yellow-skinned yellow-fleshed Longshu No. 7 potatoes are used as raw materials.

Preparation Process:

(1) Potato cleaning: Use a potato cleaning machine to clean the potatoes. During the cleaning process, manually pick out the rotten, germinated and green potatoes;

(2) Potato peeling: Use a peeling machine to remove the potato skin;

(3) Potato slices: use a potato slicer to cut the potatoes into thin slices with a thickness of 2 mm, and immediately soak the cut potato slices in the color protection solution for color protection;

(4) Color protection: Soak the cut potato slices in the color protection solution for 10 minutes. The color protection solution is a solution containing 2g/L vitamin C and 1g/L citric acid prepared from tap water;

(5) Drain: Take the potato slices out of the color protection solution and place them in a mesh sieve to drain;

(6) Electric blast drying: put the drained potato chips into an electric blast drying oven for drying and dehydration at 40°C until the moisture content of the potato chips is reduced to less than 10%;

(7) Crush, sieve, and package: Immediately crush the potato chips dried by electric blast, pass through a 80-mesh sieve (the potato flour that fails to pass the sieve is re-crushed), and package, that is, electric blast dried potatoes Raw whole powder.

Embodiment two

Potato raw material: Fresh Dongnong 306 purple potato with jet-black skin and purple-black pulp is used as raw material.

Preparation Process:

(1) Potato cleaning: Use a potato cleaning machine to clean the potatoes. During the cleaning process, manually pick out the rotten, germinated and green potatoes;

(2) Potato peeling: Use a peeling machine to remove the potato skin;

(3) Potato slices: use a potato slicer to cut the potatoes into strips of 2×2×10 cm, and soak the cut potato strips in the color protection solution immediately for color protection;

(4) Color protection: Soak the cut potato strips in the color protection solution for 20 minutes. The color protection solution is a solution containing 2g/L vitamin C and 0.5 g/L sodium bisulfite prepared from tap water;

(5) Drain: Take the potato strips out of the color protection solution and put them in a mesh sieve to drain;

(6) Electric blast drying: immediately put the drained potato strips into an electric blast drying oven for drying and dehydration at a drying temperature of 50°C until the moisture content of the potato strips is reduced to less than 15%;

(7) Grinding, sieving, packaging: Immediately crush the potato strips dried by electric blast, pass through a 100-mesh sieve (the potato flour that fails to pass through the sieve will be crushed again), and packaged, that is, electric blast dried potatoes Raw whole powder.

Embodiment three

Potato raw material: Longshu No. 10 potato with yellow skin and yellow flesh is used as raw material.

Preparation Process:

(1) Potato cleaning: Use a potato cleaning machine to clean the potatoes. During the cleaning process, manually pick out the rotten, germinated and green potatoes;

(2) Potato peeling: Use a peeling machine to remove the potato skin;

(3) Potato dicing: Use a machine to cut potatoes into dices of 2×2×2 cm, and put the diced potatoes into the color protection solution immediately for color protection;

(4) Color protection: Soak the diced potatoes in the color protection solution for 30 minutes. The color protection solution is a solution containing 1 g/L citric acid and 0.5 g/L sodium bisulfite prepared from tap water.

(5) Drain: Take the diced potatoes out of the color protection solution and place them in a mesh sieve to drain;

(6) Electric blast drying: immediately put the drained diced potatoes into an electric blast drying oven for drying and dehydration at 60°C until the moisture content of the potato chips is reduced to less than 5%;

(7) Crush, sieve, and package: Immediately crush the diced potatoes dried by electric blast, pass through a 140-mesh sieve (the potato flour that fails to pass the sieve will be crushed again), and packaged, that is, electric blast dried potatoes Raw whole powder.

Claims (7)

1. The process of preparing raw potato powder by electric blast drying method is to wash, peel and cut fresh potato tubers, soak them in color protection solution, take them out and drain them, and then put them into an electric blast drying box Carry out electric blast drying and dehydration; then crush, sieve, and pack to get raw potato powder. 2. The process for preparing raw potato powder by electric blast drying method according to claim 1, characterized in that: said potatoes are common fleshy potato varieties and colored fleshy potato varieties. 3. The process for preparing raw potato powder by electric blast drying method according to claim 1, characterized in that: said dicing is cutting potatoes into potato slices, potato dices or potato strips. 4. The process for preparing raw potato powder by electric blast drying method according to claim 1, characterized in that: soaking and protecting the color in the color-protecting liquid is soaking the cut potatoes in the color-protecting liquid for 10-30 minutes. min. 5. as claimed in claim 1, the process of preparing raw potato powder by electric blast drying method is characterized in that: said color protection solution is vitamin C, citric acid, and sodium bisulfite whose concentration is 1 to 3 g/L at least one of the solutions. 6. The process of preparing raw potato powder by electric blast drying method according to claim 1, characterized in that: the temperature of the electric blast drying and dehydration is 40°C~60°C, and the moisture content of the potatoes after drying and dehydration is 5% ~15%. 7. The process for preparing raw potato powder by electric blast drying method according to claim 1, characterized in that: after pulverization and sieving, the particle size of the raw potato powder product is 80-140 mesh.