Potato chips are thin slices of potato, fried quickly in oil and then salted.
According to snack food folklore, the potato chip was invented in 1853 by a chef named George Crum at a restaurant called Moon's Lake House in Saratoga Spring, New York. Angered when a customer, some sources say it was none other than Cornelius Vanderbilt, returned his french fried potatoes to the kitchen for being too thick, Crum sarcastically shaved them paper thin and sent the plate back out. The customer, whoever he was, and others around him, loved the thin potatoes. Crum soon opened his own restaurant across the lake and his policy of not taking reservations did not keep the customers from standing in line to taste his potato chips.
The popularity of potato chips quickly spread across the country, particularly in speakeasies, spawning a flurry of home-based companies. Van de Camp's Saratoga Chips opened in Los Angeles on January 6, 1915. In 1921, Earl Wise, a grocer, was stuck with an overstock of potatoes. He peeled them, sliced them with a cabbage cutter and then fried them according to his mother's recipe and packaged them in brown paper bags. Leonard Japp and George Gavora started Jays Foods in the early 1920s, selling potato chips, nuts, and pretzels to speakeasies from the back of a dilapidated truck.
The chips were commonly prepared in someone's kitchen and then delivered immediately to stores and restaurants, or sold on the street. Shelf-life was virtually nil. Two innovations paved the way for mass production. In 1925, the automatic potato-peeling machine was invented. A year later, several employees at Laura Scudder's potato chip company ironed sheets of waxed paper into bags. The chips were hand-packed into the bags, which were then ironed shut.
Potato chips received a further boost when the U.S. government declared them an essential food in 1942, allowing factories to remain open during World War II. In many cases, potato chips were the only ready-to-eat vegetables available. After the war, it was commonplace to serve chips with dips; French onion soup mix stirred into sour cream was a perennial favorite. Television also contributed to the chip's popularity as Americans brought snacks with them when they settled before their television sets each night.
In 1969, General Mills and Proctor & Gamble introduced fabricated potato chips, Chipos and Pringles®, respectively. They were made from potatoes that had been cooked, mashed, dehydrated, reconstituted into dough, and cut into uniform pieces. They further differed from previous chips in that they were packaged into breakproof, oxygen-free canisters. The Potato Chip Institute (now the Snack Food Association) filed suit to prevent General Mills and Proctor & Gamble from calling their products chips. Although the suit was dismissed, the USDA did stipulate that the new variety must be labeled as "potato chips made from dried potatoes." Although still on the market, fabricated chips have never achieved the popularity of the original.
Today, potato chips are the most popular snack in the United States. According to the Snack Food Association, potato chips constitute 40% of snack food consumption, beating out pretzels and popcorn in spite of the fact that hardly anyone thinks potato chips are nutritious. Nonetheless, the major challenge faced by manufacturers in the 1990s was to develop a tasty low-fat potato chip.
Even though Earl Wise started his business with old potatoes, today's product is made from farm-fresh potatoes delivered daily to manufacturing plants. The sources vary from season to season. In April and May, potatoes come from Florida; June, July and August bring potatoes from North Carolina and Virginia; in the autumn months, the Dakotas supply the majority of potatoes; during the winter, potato chip manufacturers depend on their stored supplies of potatoes. Stored potatoes are kept at a constant temperature, between 40-45°F (4.4-7.2°C), until several weeks before they are to be used. They are then moved to a reconditioning room that is heated to 70-75°F (21.1-23.9°C). Size and type are important in potato selection. White potatoes that are larger than a golf ball, but smaller than a baseball, are the best. It takes 100 lb (45.4 kg) of raw potatoes to produce 25 lb (11.3 kg) of chips.
The potatoes are fried in either corn oil, cottonseed oil, or a blend of vegetable oils. An antioxidizing agent is added to the oil to prevent rancidity. To further insure purification, the oil is passed through a filtration system daily. Salt and other flavoring ingredients, such as powdered sour cream and onion and barbecue flavor, are purchased from outside sources. Flake salt is used rather than crystal salt. Some manufacturers treat the potatoes with chemicals such as phosphoric acid, citric acid, hydrochloric acid, or calcium chloride to reduce the sugar level, and thus improve the product's color. The bags are designed and printed by the individual potato chip manufacturer. They are stored on rolls and brought to the assembly line as necessary.
- 1 When the potatoes arrive at the plant, they are examined and tasted for quality. A half dozen or so buckets are randomly filled. Some are punched with holes in their cores so that they can be tracked through the cooking process. The potatoes are examined for green edges and blemishes. The pile of defective potatoes is weighed; if the weight exceeds a company's preset allowance, the entire truckload can be rejected.
- 2 The potatoes move along a conveyer belt to the various stages of manufacturing. The conveyer belts are powered by gentle vibrations to keep breakage to a minimum.
Destoning and peeling
- 3 The potatoes are loaded into a vertical helical screw conveyer which allows stones to fall to the bottom and pushes the potatoes up to a conveyer belt to the automatic peeling machine. After they have been peeled, the potatoes are washed with cold water.
- 4 The potatoes pass through a revolving impaler/presser that cuts them into paper-thin slices, between 0.066-0.072 in (1.7-1.85 mm) in thickness. Straight blades produce regular chips while rippled blades produce ridged potato chips.
- 5 The slices fall into a second cold-water wash that removes the starch released when the potatoes are cut. Some manufacturers, who market their chips as natural, do not wash the starch off the potatoes.
- 6 If the potatoes need to be chemically treated to enhance their color, it is done at this stage. The potato slices are immersed in a solution that has been adjusted for pH, hardness, and mineral content.
Frying and salting
7 The slices pass under air jets that remove excess water as they flow
into 40-75 ft (12.2-23 m) troughs filled with oil. The oil temperature
is kept at 350-375°F (176.6-190.5°C). Paddles gently push the
slices along. As the slices tumble, salt is sprinkled from receptacles
positioned above the trough at the rate of about 1.75 lb (0.79 kg) of
salt to each 100 lb (45.4 kg) of chips.
- 8 Potato chips that are to be flavored pass through a drum filled with the desired powdered seasonings.
Cooling and sorting
- 9 At the end of the trough, a wire mesh belt pulls out the hot chips. As the chips move along the mesh conveyer belt, excess oil is drained off and the chips begin to cool. They then move under an optical sorter that picks out any burnt slices and removes them with puffs of air.
- 10 The chips are conveyed to a packaging machine with a scale. As the pre-set weight of chips is measured, a metal detector checks the chips once more for any foreign matter such as metal pieces that could have come with the potatoes or been picked up in the frying process.
- 11 The bags flow down from a roll. A central processing unit (CPU) code on the bag tells the machine how many chips should be released into the bag. As the bag forms, (heat seals the top of the filled bag and seals the bottom of the next bag simultaneously) gates open and allow the proper amount of chips to fall into the bag.
- 12 The filling process must be accomplished without letting an overabundance of air into the bag, while also preventing the chips from breaking. Many manufacturers use nitrogen to fill the space in the bags. The sealed bags are conveyed to a collator and hand-packed into cartons.
- 13 Some companies pack potato chips in I O cans of various sizes. The chips flow down a chute into the cans. Workers weigh each can, make any necessary adjustments, and attach a top to the can.
Taste samples are made from each batch throughout the manufacturing process, usually at a rate of once per hour. The tasters check the chips for salt, seasoning, moisture, color, and overall flavor. Color is compared to charts that show acceptable chip colors.
Preventing breakage is a primary goal for potato chip manufacturers. Companies have installed safeguards at various points in the manufacturing process to decrease the chances for breakage. The heights that chips fall from conveyer belts to fryers have been decreased. Plastic conveyer belts have been replaced with wide mesh stainless steel belts. These allow only the larger chips to travel to the fryers and the smaller potato slivers to fall through the mesh.
Rejected potatoes and peelings are sent to farms to be used as animal feed. The starch that is removed in the rinsing process is sold to a starch processor.
Potato chips show no sign of declining in popularity. However, the public's increased demand for low-fat foods has put manufacturers on a fast track to produce a reduced-calorie chip that pleases the palate as well. In the late 1990s, Proctor and Gamble introduced olestra, a fat substitute that was being test-marketed in a variety of products, including potato chips.
Food technicians are using computer programs to design a crunchier chip. Upper- and lower-wave forms are fed into the computer at varying amplitudes, frequencies, and phases. The computer then spits out the corresponding models. Researchers are also working on genetically engineered potatoes with less sugar content since it is the sugar that produces brown spots on chips.
Where to Learn More
Trager, James. The Food Chronology. Henry Holt, 1995.
"Potato Chips," Jays Foods, Chicago, IL 60628. 773/731-8400.
— Mary F. McNulty