Corn chips are made by cooking dried corn kernels in an alkaline solution, grinding them into a dough called masa, shaping that dough, and frying it in hot oil. The process starts with a technique called nixtamalization that dates back thousands of years to Mesoamerica, and modern factories still follow the same basic sequence, just at industrial scale and speed.
It Starts With the Right Corn
Not all corn works well for chips. Manufacturers use dent corn, a type of field corn with a high soft starch content that breaks down easily during cooking and grinding. White dent corn hybrids are the standard choice for masa-based products like corn chips, tortilla chips, and taco shells. These are contracted and sold specifically to dry-mill processors for alkaline cooking. Yellow dent varieties can also be used depending on their starch profile, but white corn dominates the snack food industry because it produces a cleaner flavor and lighter color in the finished chip.
Nixtamalization: The Alkaline Soak
The dried corn kernels are boiled and soaked in water mixed with calcium hydroxide, commonly called slaked lime. This alkaline bath does several things at once. It loosens and dissolves the outer hull of each kernel, making the interior easier to grind. It partially gelatinizes the starch, with the outermost layers of the kernel fully gelatinizing while the inner layers only partially break down. This gradient of starch transformation is what gives masa its distinctive sticky, pliable texture.
The alkaline treatment also improves nutrition in ways that matter. It increases the bioavailability of niacin (vitamin B3), which is naturally locked up in raw corn in a form the body can’t absorb. It improves protein quality and reduces mycotoxins, harmful compounds produced by mold that can contaminate grain. Populations that historically ate corn without nixtamalization were vulnerable to pellagra, a niacin deficiency disease. The calcium from the lime soak also ends up in the finished product, adding a small mineral boost.
After soaking, the cooked corn, now called nixtamal, is drained and washed to remove excess calcium and loose hull material.
Grinding the Dough
The nixtamal is ground between lava or aluminum oxide stones to produce fresh masa. The spacing between the grinding stones is the key variable that determines what the masa will become. For table tortillas, the stones are set close together to create a fine, smooth dough. For corn chips and other snack foods, the gap is wider, producing a coarser grind with a rougher texture. This coarser particle size gives corn chips their characteristic gritty crunch, distinct from the smoother bite of a tortilla chip.
Manufacturers can also adjust cooking time and lime concentration to fine-tune the dough for specific products. Some operations use freshly ground masa directly, while others dry the masa into masa flour (masa harina) that can be shipped, stored, and reconstituted with water at a different facility. Both approaches produce a workable dough, though fresh masa is generally considered to have a fuller corn flavor.
Shaping: Extrusion vs. Sheeting
This is where corn chips and tortilla chips take different paths. Tortilla chips are made by sheeting the masa into a thin, flat layer and then cutting it into triangles or other shapes. Those cut pieces are typically baked briefly before frying.
Corn chips skip the sheeting step entirely. Instead, the coarsely ground masa is fed into a screw-type extruder, a machine that forces the dough through a shaped die under pressure. The extruded strips or curls are cut directly as they emerge. This extrusion process is what gives corn chips like Fritos their distinctive thick, curled shape, compared to the flat geometry of a tortilla chip. The masa can be extruded into various configurations depending on the die used.
Deep Frying
The shaped chips go straight into a deep-fat fryer, either a continuous conveyor system or a batch fryer filled with vegetable oil heated to roughly 175°C to 185°C (about 350°F to 365°F). Corn chips typically fry for 60 to 90 seconds. During that short window, the moisture in the dough rapidly converts to steam and escapes, while oil moves in to replace it. The chips exit the fryer with a moisture content of only about 1.5% and an oil content around 36% of their total weight.
Frying time and temperature depend on how much moisture the raw chip carries going in. A wetter piece needs more time or higher heat. Getting this balance right is critical: too little frying leaves a tough, chewy chip, while too much creates a bitter, overly dark product.
Seasoning and Coating
Fresh from the fryer, chips are still hot and slightly oily on the surface, which helps salt and seasoning stick. At the simplest level, plain corn chips just get a dusting of fine salt. Flavored varieties receive blended seasoning powders applied in a rotating drum or on a conveyor.
Many modern snack lines use electrostatic coating systems borrowed from the industrial painting world. In this method, seasoning particles are given an electrical charge as they pass through a corona charging zone (essentially a fine wire connected to a high-voltage generator that ionizes the surrounding air). The charged powder is attracted evenly to the surface of the chip, creating a more uniform coating than simply tumbling chips through a seasoning drum. Studies comparing the two methods found that electrostatic coating produces significantly more even salt and flavor distribution, with less wasted seasoning falling to the bottom of the bag.
Corn Chips vs. Tortilla Chips
Both products start from nixtamalized corn, but the differences add up. Corn chips use a coarser grind, are extruded rather than sheeted, and go directly into the fryer without a baking step. Tortilla chips use a finer masa, are rolled flat, cut into shapes, partially baked to set their structure, and then fried. The result is that corn chips tend to be denser, crunchier, and more intensely corn-flavored, while tortilla chips are lighter and crispier with a more neutral taste that works well as a vehicle for dips and salsas.
What Frying Does to the Chemistry
High-temperature frying creates small amounts of acrylamide, a compound that forms when starchy foods are heated above about 120°C. Corn chips contain measurable levels, with published analyses finding concentrations that typically range from around 15 to several hundred micrograms per kilogram, though some samples have tested much higher. The European Commission set benchmark levels for acrylamide in various cereal-based foods (for example, 400 μg/kg for crackers), but corn-based snacks don’t have their own specific category yet. The U.S. FDA and other food safety organizations have published guidance on reducing acrylamide during manufacturing, and factors like frying time, temperature, and the sugar content of the raw corn all influence how much forms in the finished product.
Manufacturers control acrylamide primarily by keeping frying temperatures as low as practical and minimizing frying duration, which is one reason the 60 to 90 second fry time is tightly monitored on commercial lines.