|Sweet Potato Chips Making
I. A Brief Overview of Sweet Potato
Sweet potato, also called lpomoea batatas, is a dicotyledonous plant. Its large, starchy, sweet-tasting, tuberous roots are a root vegetable. The young leaves and shoots are sometimes eaten as greens. Sweet potatoes do not simply contain starches. Raw sweet potatoes are rich in complex carbohydrates, dietary fiber, and beta-carotene, while having moderate contents of other micronutrients. Compared to other foods, sweet potatoes rank highest in nutritional value.
Although the leaves and shoots of sweet potatoes are also edible, the starchy tuberous roots are by far the most important product. In some tropical areas, they are a staple food crop.
In Africa, sweet potatoes are an important food for people. It is mainly served for breakfast, eaten with peanut sauce. The baked root is eaten as a snack anytime and is mostly served with tea or with peanut sauce. South Sudan also eat sweet potatoes in a similar way.
In Asia, there are different ways of cooking sweet potatoes. In China, sweet potatoes are baked in a large iron drum, and sold as street food during winter, or boiled in water to make soup. In Korea, sweet potatoes are baked in foil or in open fire. In India, sweet potatoes are one of the prime sources of sustenance. It is also a popular variety of preparation which is roasted slow over kitchen coals and eaten with some dressing–primarily salt, yogurt.
|In North America, sweet potatoes are a side dish that contains sweet potatoes, sugar, marshmallows, maplw syrup, molasses, orange juice, marron glace, or other sweet ingredients. Sweet potato fries or chips are common preparation and are made by julienning and deep frying sweet potatoes.
With red color, the juice of red sweet potatoes is combined with lime juice to make a dye for cloth. By varying the proportions of the juices, every shade from pink to black can be got. As to other uses, all parts of the plant are used for animal fodder. People also use sweet potatoes in Moche ceramics.
II. How to Make Sweet Potato Chips?
Sweet potato chips are made from fresh sweet potatoes, with high nutritious value. When fresh sweet potatoes are cooked by baking, small variable changes in micronutrient content occur to include a higher content of vitamin C at 24% of the Daily Value per 100 g serving, as well as an increase in polyphenol levels. Sweet potato chips are good for people’s health and are popular around the world with special sweetness, luster, crispy and beautiful colors. There are two kinds of sweet potato chips, baked potato chips, and fried potato chips. There are two kinds of sweet potato chips, baked sweet potato chips, and fried potato chips. Here are the ways of making sweet potato chips.
1. Baked Sweet Potato Chips Making Process
Material: fresh sweet potatoes, cornstarch, flour, peanut oil, shortening, citric acid, salt, raising agent, savory flavoring
Sweet potatoes→cleaning→peeling→rinsing→slicing→color protection→color protection→stewing→dehydration→blending→molding→baking→packing
Cleaning: pick out the fragile, large sweet potatoes without decaying, plant diseases, and insect pests. Put them into the water. If the production is big, use a potato washing and peeling machine to clean and peel which can save labor and time, and cost.
Peeling and Rinsing: use a peeling machine or hot water on the skin. Then the peeled sweet potatoes should be immersed in water to rinse, in order to prevent browning in the air, and wash away the free starch on the surface.
Slicing and Color Protection: weed out the unqualified. Then use the potato slicing machine to slice sweet potatoes into a 1.5~2mm thickness in order to stew slices evenly. Put the slices into 1.5% NaCl solution and 0.1% citric acid solution.
Stewing: drain the slices and stew them for 15~20min. Take the translucent and faintly visible piece of the sweet potato fiber as a sign of full gelatinization.
Dehydration: use 60℃ hot wind to dry the slices until the water content is reduced to 35%. The water content affects the blending process and the quality of the product.
Blending: mash the slices into the mud. According to a different flavor and the relevant formula, blend auxiliary material(cornstarch, flour, shortening, citric acid, salt, raising agent, savory flavoring) and the sweet potato mud.
Molding: put potato mud on the noodle press to make 1~3mm thickness chips. Take out the unqualified with a standard that sweet potato chips whether glue roller, the surface is smooth and level off, without shrinkage deformation.
Baking: according to the water content of the product, the baking temperature is determined to be 140~160℃. The baking temperature is important in the production line. If the temperature is too high, the water will volatilize quickly and the chips are easy to curly and deform and become brown. If it is too low, water will volatilize too slow which extends the baking time and make the color of the chip white, poor crisp, and affect the flavor and appearance of the product. Mastering the baking temperature can make high-quality chips.
Packing: use Nitrogen & Vacuum potato chips packing machine which can prevent the oxidation reaction and extend the sweet potato chips’ shelf life.
2. Fried Sweet Potato Chips Making Process
Material: sweet potatoes, vegetable oil
Selecting: pick out the fresh sweet potatoes in a suitable size. Get rid of the ones with decaying, decaying, plant diseases, and insect pests.
Washing and peeling: use the potato washing and peeling machine. Wash away the sediment and dirt on the surface of the sweet potatoes and peel them. When peeling, cut off the parts with black patches.
Slicing: use the potato chips machine. Adjust the machine to make the thickness 2.0mm~4.0mm. Using the potato chips machine can get the chips of similar size, uniform, and thickness.
Blanching: put the slices into the 1.0%~3.0%NaCl solution to blanch for 0.5~2.0 min until the sweet potato slices turn transparent.
Cooling and dehydration: use the flowing water to cool the slices or use the 7℃ circulating water to cool the slices to 15℃. Then use the potato slices dehydration machine to remove the water on the surface of the cooling slices.
Freezing: use the French fries freezing machine to freeze the sweet potato chips until the temperature of the chip is -18℃. Freeze the sweet potato chips can volatilize quickly in the frying process and produce a large amount of mesh structure to make the product crispy and the surface smooth.
Frying: Heat the oil to 110℃, and set the compensation temperature as 75℃. Then fry the sweet potato chips for 2min, and keep the oil temperature is above 78℃ with the compensation heating until frying is done. The technology of vacuum low-temperature frying can retain the nutrition of sweet potatoes without damage. Under the condition of vacuum low temperature, the oil will not go bad so that it does not contain the cancerogenic substance.
De-oiling: use the potato chips de-oiling machine to remove the oil on the surface of the sweet potato chips. Put the slices in the machine and rotate for 6min. The oil content is a key to high-quality chips.
Packing: use Nitrogen & Vacuum potato chips packing machine which can prevent the oxidation reaction and extent the sweet potato chips shelf life.