Types and principles of puffed food.
Types and principles of puffed food.
Puffed foods, also known as extruded foods, blasting foods, and light foods, are a new type of food developed internationally in recent years. It uses cereals, beans, potatoes, vegetables, etc. as raw materials, and through the processing of puffing equipment, it produces a variety of foods with exquisite appearance, nutrient-rich, crisp and delicious. Therefore, a large class of food has been formed uniquely.
Since the equipment for producing such puffed food is simple in structure, easy to operate, low in equipment investment, and fast in profit, it develops very rapidly and exhibits great vitality.
Due to the different uses and equipment, there are three types of puffed foods: one is to use squeeze type extruder to produce small foods from corn and potato; the other is to use extrusion type extruder to produce vegetable protein as raw material. Tissue protein food (plant meat); three is based on cereals, beans or potatoes, and is made into a staple food after being expanded. In addition to the trial production of the indirect heating extruder, a variety of puffed foods were also prepared using the refined powder puffing powder.
Puff Snacks Type.
1. Staple food: biscuits, bread, taro, pancakes, etc.
2. Oil tea category: puffed face tea. Kurkure, cheetos, bugles, doritos and so on.
3. Military food: compressed biscuits.
4. Pastry categories: peach cake, stove fruit, eight pieces, crispy cakes, moon cakes, printed cakes, egg rolls, etc.
5. Small food categories: rice candy, brown cake, etc.
6. Cold food: filling materials for ice cream and popsicles.
Among the above-mentioned foods, some varieties such as puffed noodles, printed cakes, and compressed biscuits are all made of expanded coarse grains; some varieties only incorporate a certain proportion of puffed coarse grains. Although the puffing technology belongs to the physical processing technology, it has its own characteristics. Puffing not only changes the shape and state of the raw materials, but also changes the molecular structure and properties of the raw materials, and forms some new substances.
When the grain is placed in the extruder, as the heating and pressurization progress, the water in the grain is overheated, and the grain itself becomes soft. When a certain high pressure is reached and the expander cap is opened, the high pressure changes rapidly. At normal pressure, the water in the superheated state of the grain suddenly explodes in a moment and a strong explosion occurs. The water molecules can expand about 2,000 times. The huge expansion pressure not only destroys the external shape of the grain, but also pulls The intrinsic molecular structure of the grain is broken, and the insoluble long-chain starch is chopped into water-soluble short-chain starch, dextrin and sugar, so that the insoluble matter in the puffed food is reduced, and the water-soluble substance is increased.
After the expansion, in addition to the increase in water-soluble substances, a part of the starch becomes dextrin and sugar. The puffing process changes the material state and properties of the raw materials, and produces new substances. That is to say, the physical means of puffing is used to change the chemical properties of the products. This phenomenon poses a new topic for the theoretical study of food processing. .
The process of decomposing starch in food into dextrin and sugar is generally found in people's digestive organs. That is, when people eat food into the cavity, they can use the action of amylase in saliva to crack the starch. Dextrin, maltose, and finally glucose is absorbed by the body. The puffing technology acts as an amylase, which causes the starch to undergo a cracking process before the food has entered the oral cavity. In this sense, the puffing device is equivalent to prolonging the digestive organs. This increases the body's digestion process of food and improves the digestion and absorption rate of puffed food. Therefore, the expansion technology can be considered as a scientific and ideal food processing technology.
Another feature of the puffing technology is that it completely gelatinizes the starch. In the past, the hot processing technology that matures the food, such as baking, cooking, etc., can also turn the raw starch of the food, ie, beta starch, into alpha starch, so-called alpha. However, after the products are left for a period of time, the already-expanded alpha starch shrinks back to beta starch, which is called "rejuvenation" or "aging". This is a ubiquitous phenomenon in all starch-containing foods. After the "aging" of these foods, the body shape becomes hard, the taste is deteriorated, and the digestibility is lowered. This is due to the incompleteness of starch alpha.
The puffing technology can completely gelatinize the starch, and the alpha starch that has become can not be restored to beta starch after being placed, so the food maintains softness, good flavor and high digestibility, which is superior to other physical processing in puffing technology. Yet another feature of the method is that it opens up a new field of processing for coarse grain work.
Puff Snacks Advantage.
1. Improved taste and taste: After the coarse grain is puffed, the structure of the rough and hard structure is destroyed, and the coarse grain is no longer seen. The taste of the coarse grain can not be eaten, the taste is soft, the taste is improved, and it is delicious.
2. Convenient to eat: After the whole grain has been puffed, it has become a cooked food. It can be directly washed with boiling water, or made into compressed food, or processed into a variety of foods. Save time and time. As long as the food sector or factories, mines, enterprises, institutions, and schools supply puffed powder, they can be processed and prepared in the family or group canteens, becoming a convenient convenience food.
3. The preservation rate and digestibility of nutrients are high; the preservation rate of nutrients during the expansion process is shown in Tables 1-3. From the data in the table, the nutrient preservation rate and digestibility of the puffed foods are relatively high, which indicates that the puffing process has no effect on the nutrition of the food, and the digestibility is higher than that of the unexpanded.
4. Easy to store: When the grain is puffed, it is equivalent to a high temperature sterilization. The moisture content of the puffed powder is reduced to less than 10%. This low moisture limits the growth of insects and mildew and enhances their stability in storage. It is suitable for long-term storage, and is suitable for making military preparations for military use and improving its eating quality.
5. Cheap price: Apply indirect heating extruder. After processing kilograms of corn into puffed powder, the processing fee is about 6 points, which means that the price per kg of puffed corn flour is 2 cents and 6 cents. The monthly expenditure of local workers in China is 10 kilograms per person, and the monthly expenditure per person is only increased by 6 cents. This is economically affordable. If a continuous automatic extruder is developed in the future, the processing cost can be further reduced.
The Avan Machinery is a professional factory on extrusion puff snacks food machines. Welcome contact us for more information.