Garlic is a perennial herb of the genus Allium in the lily family, and is an important condiment, vegetable and important medicinal plant. Xinjiang is the place of origin of garlic. Xinjiang garlic is known as “garlic with high allicin content”. However, fresh garlic has a short dormant period, is easy to germinate and rot, and is not resistant to storage. At present, the loss of fresh garlic in our country has reached more than 30%, causing waste and economic losses. And garlic deep-processed products have become popular medicines and health foods in North America, Europe, Asia and other places, with a large demand. Therefore, garlic is a research hotspot in the fields of food processing and agriculture. Dried garlic flakes are the most basic form of dried garlic products. Garlic powder can be produced by further pulverizing dried garlic flakes. Garlic powder has higher health value because of its higher organic sulfide content.
This article explores the preparation method of garlic deep-processing garlic flakes and garlic powder. Because of its short processing time and simple process, adding freezing technology to traditional processing can reduce the loss of garlic and improve the quality of garlic flakes and garlic powder. On the basis of maintaining the original color, aroma, and nutritional content, prolonging the storage period, and enhancing the competitiveness of Xinjiang garlic brand and Xinjiang garlic in the country, is a method of value-added garlic.
First.Materials and Instruments
1. Test materials
The garlic for the test was white-skinned garlic produced by Dayous Township, Jimusar County.
Garlic peeling and splitting machine; medical low temperature box MDF382E (CN); electric heating constant temperature blast drying box; SL300E automatic slicer; XTP-100A high-speed multifunctional swinging grinder.
Acceptance of raw materials → peeling and splitting → washing → flotation → quick freezing → slicing → color protection → drying → powdering → balancing moisture → packaging → inspection.
1. Raw material collection and acceptance
Garlic harvest performance: The upper part of the leaves is yellow, the base of the pseudostem is soft, most of the plants begin to fall, the epidermis of the garlic is black, and the garlic is full.
The moisture content of garlic cloves directly affects the quality of garlic mechanical processing products. The moisture content is large. It is easy to be broken when processing mechanical peeling and dividing flaps, causing mechanical damage and affecting the quality of product slices. Therefore, the moisture content of garlic cloves should be less than 70% when harvesting. It can be left open for 3 to 5 days after harvest.
The purchased garlic raw materials must be neat and uniform in appearance, meet the production requirements for garlic varieties and garlic size (usually 3.0 to 4.5 cm in diameter), have no mildew, no pests and no impurities, and have the unique flavor and color of garlic. Odor and no discoloration.
2. Peeling split flap
Because the size of each batch of garlic is different, you need to debug the equipment first, put a small amount of garlic to test the splitting effect, and adjust the gap between the upper and lower rubber plates according to the size of the garlic. The garlic has a large gap and a small garlic. Collect the garlic cloves at one outlet, and clean up the garlic skin, garlic stalks, garlic roots and root soil after the separation at the other outlet.
Wash the garlic cloves 3 times with water in the washing tank. Cleaning the garlic cloves can effectively remove the debris and dirt on the surface of the garlic, and timely replace the water in the cleaning tank according to the amount of feed and the degree of cleanliness.
Rinse and float to remove impurities such as garlic skin, and manually select and remove black, brown or rotten garlic cloves and garlic cloves that have not been cut. Drain the washed garlic slices to dry.
Temperature has a direct impact on the activity of alliinase. Alliinase is a heat-sensitive enzyme. Its optimum temperature is about 40 ° C. When the temperature is higher than 55 ° C, the enzyme activity will rapidly decrease. Therefore, reducing the temperature of garlic before slicing can greatly reduce the loss of bioactive components in garlic. Place garlic cloves in the freezer. The temperature in the freezer is below -25 ° C. After quick freezing, the center temperature of the product is below -18 ° C, which takes about 4-6 hours.
Slice thickness is 3 mm. The thinner the garlic slices, the lower the thiosulfinate retention rate after drying. The thicker the slice, the more difficult it is for the moisture to migrate from the inside of the material to the surface after entering the reduced-speed drying stage, and the drying time is prolonged, resulting in a serious decrease in the drying quality of garlic after drying.
7. Color protection
After soaking in a composite color protector (ratio 1: 1: 1: 1) composed of 0.04% sodium bisulfite, 0.1% L-cysteine, and 0.1% vitamin C for 20 minutes, drain the water.
The pre-processed garlic slices are evenly spread on the material tray, the thickness of the cloth is 4-5 cm (separated by aluminum foil paper), the input amount is 5 kg each time, and placed in a constant temperature blast drying box, taking into account that the temperature is too low It will reduce the drying speed, make the retention rate of thiosulfinate in garlic slices high, set the temperature to 55 ° C, until the final moisture content of garlic slices is 5%, and the time is 4 to 5 hours. During the drying process, keep the amount of hot air and humidity in the drying box stable, and strictly control the drying temperature and time.
9. Beat powder
Put the obtained garlic flakes and β-cyclodextrin in an amount of 6% into a pulverizer and pulverize 3 times. The pulverizing time is 30 seconds each time, and the interval is 10 minutes. The addition of β-cyclodextrin does not stick to the wall during production and does not agglomerate during storage.
10. Balance moisture
After the dried garlic slices and garlic powder are cooled, put them in a sealed bag and keep them for 1 to 2 days, so that the moisture in the dried products can be transferred to each other to achieve equilibrium.
Packaging materials should meet national food hygiene requirements. Food packaging materials must not cause direct or indirect contamination of the contents. The inner packaging is usually made of polyethylene bags or aluminum foil bags. The outer packaging should be clean, firm and solid, and can be packed in cartons (lined with moisture-proof paper).
Cold storage can better maintain the original nutrients, color and flavor of food, so it is recommended to store at low temperature. The temperature is controlled at -2.5 ～ 3.0 ℃, and the relative humidity in the library is controlled below 65%. The refrigerated warehouse should be clean, dry and ventilated, and the stack should be more than 0.5 meters away from the ground and walls.
Third, quality standards
1. Sensory indicators
①Garlic flakes Milky white or milky yellow, flakes are complete, no curl, with spicy flavor unique to garlic.
②Garlic powder Milky white or milky yellow, fine granules, consistent size, with spicy flavor unique to garlic.
2.Physical and chemical indicators
Water content ≤5%.
3. Microbiological indicators
Total bacteria: <1 000cfu / g; E. coli: <30MPN / 100g; pathogenic bacteria: not detected.