CN104872581A - Potato raw flour preparing process by vacuum drying method - Google Patents

Abstract

The invention provides a potato raw flour preparing process by the vacuum drying method and belongs to the technical field of potato processing. The process includes adopting fresh potatoes as raw material, cleaning, peeling and dicing the potatoes, soaking the potatoes through color protecting liquid to protect color, fetching and draining the potatoes before placing into a vacuum drying box to perform vacuum drying; obtaining the potato raw flour after smashing, filtering and packaging. The color, flavor and taste of potatoes can be remained to the utmost extent, the quality of the obtained potato raw flour is high, the protein has the biological activity, protein crosslink occurs to form a gluten network structure during dough making, the processing performance problem is solved when the potato dough is used for noddle and bread processing, and the significance is provided for promoting potatoes to be staple foods.

Description

Process for preparing raw potato powder by vacuum drying method

technical field

The invention relates to a process for preparing raw potato powder, in particular to a process for preparing raw potato powder by a low-temperature vacuum drying method, and belongs to the technical field of potato processing.

Background technique

In 2015, the Ministry of Agriculture announced that my country will start the strategy of turning potatoes into a staple food, and promote the processing of potatoes into staple foods such as steamed bread, noodles, and rice noodles. Potatoes will become another staple food besides rice, wheat, and corn. It is estimated that more than 50% of potatoes will be consumed as a staple food in 2020.

Potatoes are known as a "perfect" nutritional product, rich in dietary fiber and low in fat, which is beneficial to control weight gain, prevent high blood pressure, high cholesterol and diabetes. In fact, many countries in the world use potatoes as their staple food. For example, the per capita annual consumption in European countries is stable at 50-60 kg, and the per capita consumption in Russia reaches more than 170 kg. At present, only a few areas in China use potatoes as a staple food, and more areas use potatoes as vegetables.

French fries are an important form of potato as a staple food in European and American countries. In order to change the consumption of potatoes from non-staple food to staple food in China in the future, it is necessary to develop staple foods such as potato bread, steamed buns, and noodles according to Chinese food culture and consumption habits. product. 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.

Potato protein is very different from the flour used for making noodles or steamed bread. The denaturation temperature and starch gelatinization temperature of potato protein are both about 70°C. The low-temperature drying method is used to ensure protein biological activity and starch without gelatinization to prepare raw potato powder. In the production of noodles and steamed bread, it plays an important role in improving the processing performance of dough.

Contents of the invention

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

The process of preparing raw potato powder by the low-temperature vacuum drying method of the present invention is to wash, peel and cut fresh potato tubers into pieces, soak them in a color-protecting solution, take them out and drain them, and then put them into an electric blast drying box. Electric blast drying and dehydration; then pulverized, sieved, and packaged to become 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 vacuum drying and dehydration is 40°C-60°C, and the degree of vacuum is 80.00-99.99kPa; the moisture content of the potatoes after drying and dehydration is 5%-15%. The vacuum drying container can be large or small, and can be intermittent, sequential batch or continuous drying system. According to production requirements, special equipment is required.

The particle size of the whole raw potato powder product after crushing and sieving is 80-140 mesh.

Compared with the prior art, the present invention has the following advantages: the present invention adopts low-temperature vacuum drying technology, so that the potatoes are in a vacuum and closed environment during the whole drying process, and the drying process is mild (product temperature 40-60°C). , can keep the color, fragrance and taste of the potato to the greatest extent, and obtain a high-quality final product. 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. In addition, under vacuum and low pressure, potato chips (dices and strips) evaporate quickly at medium and low temperatures, so the operating cost of dehydration and drying is relatively low, which are 1/3 of ordinary oven drying and 1/6 of freeze drying. .

Detailed ways

The preparation process of raw potato powder of the present invention will be further described by specific examples below.

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) Vacuum drying: Put the drained potato slices into a vacuum drying oven immediately for vacuum drying and dehydration. The drying temperature is 40°C and the vacuum degree is 99.00kPa until the moisture content of the potato slices is reduced to less than 10%.

(7) Grinding, sieving, and packaging: immediately crush the vacuum-dried potato chips, pass through an 80-mesh sieve (the potato flour that fails to pass the sieve is crushed again), and pack, which is the whole potato freeze-dried 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) Vacuum drying: Put the drained potato strips into a vacuum drying oven immediately for vacuum drying and dehydration. The drying temperature is 50°C and the vacuum degree is 90.00kPa until the moisture content of the potato strips is reduced to less than 15%.

(7) Crush, sieve, and package: immediately crush the vacuum-dried potato chips, pass through a 100-mesh sieve (the potato flour that fails to pass the sieve is re-crushed), and package, that is, the raw potato freeze-dried 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) Vacuum drying: Put the drained diced potatoes into a vacuum drying oven immediately for vacuum drying and dehydration. The drying temperature is 60°C and the vacuum degree is 80.00 kPa until the moisture content of the potato chips is reduced to less than 5%.

(7) Crush, sieve, and package: immediately crush the vacuum-dried potato chips, pass through a 140-mesh sieve (the potato flour that fails to pass the sieve is re-crushed), and package, that is, the whole potato freeze-dried powder.

Claims (7)

1. boulton process prepares the technique of potato starch, is by fresh potato stem tuber after cleaning, peeling, stripping and slicing, first soaks with colour protecting liquid and protects look, put into vacuum drying chamber and carry out vacuum dehydration after taking-up drains; Then potato starch is through pulverizing, sieving, pack.

2. as claim 1 boulton process prepares the technique of potato starch, it is characterized in that: described potato is common meat Potato Cultivars, colored meat Potato Cultivars.

3. as claim 1 boulton process prepares the technique of potato starch, it is characterized in that: potato are cut into potato block, potato fourth or potato slices in described stripping and slicing.

4., as claim 1 boulton process prepares the technique of potato starch, it is characterized in that: described colour protecting liquid soak protect look be by stripping and slicing after potato be dipped in colour protecting liquid and soak 10 ~ 30 min.

5. as claim 1 boulton process prepares the technique of potato starch, it is characterized in that: at least one in the vitamin C of described colour protecting liquid to be concentration be 1 ~ 3 g/L, citric acid, solution of sodium bisulfite.

6. as claim 1 boulton process prepares the technique of potato starch, it is characterized in that: the temperature of described vacuum dehydration is 40 DEG C ~ 60 DEG C, and vacuum is 80.00 ~ 99.99kPa; After drying and dehydrating, potato moisture is 5% ~ 15%.

7., as claim 1 boulton process prepares the technique of potato starch, it is characterized in that: pulverize, sieve after the granular size of potato starch product be 80 ~ 140 orders.