Potato is a commonly seen food almost around the world. In all sorts of ways to eat, fried chips must be the most attractive one to people. The reason why we can fry out the crisp and savory chips is that the starch content in potatoes is high. After warmed up, starch molecules are connected together and burnt effect generates. Dry them and then fry them with oil, the temperature is readily to get up to 302F. Under the degrees, the sugar molecules in starch will react caramel effect. For the one side, starch is dehydrated and combined, and then generates caramel pigment. There will be allure golden and brown color when the content of caramel pigment is not high. However, if the content of caramel pigment is over high, or over reacted thus gives rise to carbonize, it can’t be eaten after all. And for the other side, it degrades and releases out volatile molecules which bring us the special savor of fried chips.
Different places have different ways to fry potatoes, and the principle is almost the same. But fry potatoes to a highest degree, it must be the American snacks—hamburgers and fried chips, which nearly become the representatives of American foods. The American fried chips are crisp outside and soft inside, with even color and less different colors. Moreover, no matter which day you go, whatever snack bars you enter, the fried chips are all the same with the same brand.
How did they do that?
The consistency of the fried chips comes from the accordance of ingredients and standardization of the operation. Take it for example, they would use the same sort of potatoes, control the process flow fine and meticulous, and complete the most processes in central kitchen. And the last step finished by stores would be fry the semi-finished products under the same temperature with the same time. And offer to their guests instantly.
However, it is not easy to fry out the chips like snack bars in your kitchen. But if you master the key point in the course of frying chips, you can have a not bad taste fried chips.
First, pick out the bigger potatoes for cutting into even thickness and length bars. But if you only eat yourself, it is not that important to pursue the perfect outward appearance, but it do affect the appearance and the knife skills are important if you want to be appreciated by your guests.
Then, put the chips into the ice water, there will be two reasons for that. One is to wash away the starch on the surface, and the other is to avoid touches to the air. Wash off the starch on the surface is beneficial to shape a bright and clean surface. When potatoes are cut apart, the polyphenol oxidase would come out and oxidize the polyphenolic substance into brown and black pigment which leads to dark potatoes. Naturally the dark chips would not be perfect in their outward appearance. Fortunately it needs oxygen to take part in in this reaction, to soak them in the water contributes to isolate air and reduce oxidation. However, there is less air in the water, if you want to restrain the reaction further, you can add pinch of lemon juice in the water, in which the VC can hold up the reaction to proceed. Of course you can directly add a piece of VC, the function will be the same. In commercialized chips, they will add other additives to “protect color.”
To fry out good chips, two times are required. Before frying, drain off the chips. At the first frying, keep a lower oil temperature for about 320F, this is to cook the chips, and 6-8 minutes are needed. At the second frying, oil temperature shall be around 374F. After the chips are well-fried and cooled down, the starch in them is turned into jelly-like which has locked best part of the water. Under high temperature, the water on the surface is losing fast while the inner water is stagnant, thus makes the surface of the chips crisp. Fry them another 2-3 minutes, until the surface is golden and sizzling, and at the same time the caramel reaction is proceeded and releases savory. Chips just from the oil pan shall be eaten in time or the savory will lose and the inner water comes out and gets into the surface, crisp no more.