Packaged snacks are made in automated processes, without manual contact. Among the dozens of types that exist, we chose the four most popular to detail the manufacture: fried snacks, baked snacks, extruded snacks (those like “styrofoam”) and french fries. The unbeatable potato chips, by the way, are the oldest ancestors in the brief history of snacks. The most accepted version states that the first stick-shaped fries came out of frying pans in France, in the 17th century. In 1853, they gained a new and delicious format, cut into thin and crispy slices by the American cook George Crum. Hand frying ended in 1929, when American inventor Freeman McBeth mechanized the entire process. The other snacks were born industrialized. Corn-based ones and those that tried to imitate the taste of bacon appeared in the 1950s. The “nachos” type appeared in the following decade. The numbers prove the popularity of these treats. In the United States, every American throws away 10 kilos of snacks a year. In Brazil, this rate is around 1 kilo per year. Snacks may be delicious, but they are full of “empty calories” – that is, they are fattening and provide few nutrients. At least, they suffer little from contamination by microorganisms. “The manufacturing process at high temperatures sterilizes the product”, says food engineer Yoon Chang, from the State University of Campinas (Unicamp).
Manufacturing of the four most popular types is all done by machines.
roasts
1. In general, baked snacks are made with corn. At the beginning of the process, the corn kernels are placed in metal pots filled with water and heated. The grains are cooked until they release the shell. This can take up to eight hours.
2. Next, the corn kernels are ground to form a smooth, uniform mass. This dough is stretched by rollers, becomes thin as a blade and is cut in the shape of a triangle, getting the final “handsome” of the snack.
3. After being cut, the dough is baked in an industrial oven. In order for it to become golden, the snacks are baked on both sides. Afterwards, the snacks are fried in vegetable oil to make them crispier.
4. In the next stage, the baked and fried snacks are sent to the flavoring system. In this device, they receive powdered spices with the flavor chosen for the snack — cheese and ketchup, for example. After that, the product is ready to be packaged.
Fried
1. The raw material for this type of snacks is wheat pasta. In the first step of manufacturing, wheat flour and water are mixed in a giant mixer. Afterwards, the dough passes through rollers and is stretched in the form of a ribbon, as we see in the figure.
2. If the snack is the bacon type, the white dough is dyed with annatto to make it darker. Afterwards, it is dried by a ventilation system, cut into smaller pieces and heated for eight hours to remove moisture.
3. The next step is frying, in which the snacks are bathed in vegetable oil for nine seconds at 180°C. There are two types of fryer: the continuous one, in which a conveyor belt transports snacks through a pool of oil, and the batch one, which fries one portion at a time.
4. After frying, the snacks go to the seasoning, a kind of rotating cylinder filled with powdered seasoning used to give the taste of bacon. In the last phase, the treats go to the packing machine, which seals the bags according to the chosen weight.
Potato
1. Frit makers receive potatoes still unpeeled. In the initial stage of industrialization, the potatoes are washed and passed through an automatic cutter, which removes the skins from the vegetables.
2. Already peeled, the potatoes are sliced into smooth or wavy shapes. Afterwards, they go to a second washer, which uses hot water to remove the starch and sugar from the slices, and performs a kind of pre-cooking of the potatoes.
3. The next step is frying. Pre-cooked slices are dipped in vegetable oil at 185º C for a maximum of twenty seconds. Inside the fryer, paddles controlled by an automatic system take care of taking the potatoes out of the oil at the right time.
4. After frying, the smaller pieces are discarded. The ones that are left go to the aromatizer, where they receive the powdered seasoning. Not all of the raw material is used: to produce a kilo of french fries, 3.9 kilos of sliced potatoes are needed
Extruded
1. “Extrusados” are snacks like “styrofoam”, generally made from corn. The initial ingredient — very fine cornmeal, with grains of no more than 12 millimeters — is mixed with water until a homogeneous mass is formed.
2. This mass goes to the extrusion machine, the “heart” of the manufacturing process. The mixture receives up to 170ºC of heat, is subjected to great pressure and pressed in a matrix that gives the chosen shape for the snack
3. After passing through the die, super hot and pressed snacks come into contact with a lower pressure and cooler temperature. Result: they “explode”, getting that airy mass and the typical consistency of Styrofoam that everyone knows
4. At the end of extrusion, the snacks pass through a rotating cylinder, which has sprays that spray the desired aroma over the snacks – it can be cheese, ham or cream cheese, for example. Then the product goes to the packaging machine and is ready
Source: Yoon Kil Chang, food engineer at the State University of Campinas