Is maize starch upf or not?

January 3, 2026 •

4 min read

According to the internationally recognized NOVA food classification system, maize starch is not considered an ultra-processed food (UPF) in its plain form. However, its extensive industrial production process places it in a different category from whole foods, and modified versions are indeed classified as UPFs.

Quick Summary

Maize starch is typically a refined culinary ingredient, not an ultra-processed food (UPF) according to NOVA standards. Its status changes significantly when chemically altered into modified maize starch or used in UPF product formulations.

Key Points

NOVA Classification: Plain maize starch is a processed culinary ingredient (NOVA Group 2), not an ultra-processed food.
Modified vs. Plain: Chemically altered or 'modified' maize starch is considered an ultra-processed ingredient (NOVA Group 4) due to additional processing.
Production Process: The wet milling process used to make plain maize starch isolates and refines the starch but does not typically use the cosmetic additives that define a UPF.
Ingredient, Not End Product: Plain maize starch is often an ingredient in other ultra-processed foods, contributing to the final product's classification, but is not a UPF on its own.
Nutritional Density: As a highly refined carbohydrate, maize starch offers very little nutritional value, unlike whole corn flour, which retains fiber and micronutrients.
Additives Are Key: The primary indicator of a UPF is the presence of industrial cosmetic additives, which are not part of plain maize starch but are common in its modified versions and products containing it.

Demystifying Food Processing Levels

To understand where maize starch fits into the processing spectrum, it's crucial to first understand the classifications. The most widely cited is the NOVA system, developed by Brazilian researchers, which categorizes all foods and food products into four groups based on the extent and purpose of industrial processing.

Group 1: Unprocessed or Minimally Processed Foods. These are natural foods altered very little from their original state, with processes like washing, freezing, or drying. Think of fresh vegetables, whole grains, and plain milk. A corn cob is an example in this category.
Group 2: Processed Culinary Ingredients. Substances like oils, butter, sugar, and salt fall into this group. They are derived from Group 1 foods by industrial processes like pressing or milling and are typically not consumed on their own but used in combination with Group 1 foods. Plain maize starch is classified here.
Group 3: Processed Foods. These are simple products made by adding Group 2 ingredients (salt, oil, sugar) to Group 1 foods. Canned vegetables with salt and simple cheeses are examples.
Group 4: Ultra-Processed Foods (UPFs). Industrial formulations made mostly or entirely from substances extracted or derived from foods, often with minimal or no Group 1 content. They contain many additives (flavors, colors, emulsifiers, sweeteners) not used in home cooking. Examples include packaged snacks, sodas, and mass-produced breads.

The Journey from Corn Kernel to Maize Starch

The production of plain maize starch, also known as cornstarch, is an industrial process called wet milling. This process involves several steps to isolate the starch component from the rest of the corn kernel. While technical, this is different from the processes that create a UPF.

Steeping: Corn kernels are soaked for 30 to 48 hours in hot water with a low concentration of sulfur dioxide. This softens the kernel and begins the separation process.
Milling and Germ Separation: The softened corn is coarsely ground to separate the germ, which floats and is skimmed off to be used for corn oil.
Fine Grinding and Sieving: The remaining slurry of starch, protein, and fiber is finely ground. It is then repeatedly washed and passed through screens to separate the fiber from the starch and protein.
Starch and Gluten Separation: The final suspension is sent through a centrifuge, where the heavier starch is separated from the lighter protein (gluten).
Drying: The purified starch is then washed and dried into the familiar fine white powder.

This process does not involve adding industrial cosmetic additives like flavors, colors, or emulsifiers. It is a process of physical separation and concentration, making the final product a Group 2 culinary ingredient rather than a Group 4 UPF.

Plain vs. Modified Maize Starch: A Crucial Distinction

The processing of maize starch, however, can go a step further, crossing the line into the ultra-processed category. This distinction is critical for understanding its role in various foods.

Plain Maize Starch (Group 2)

Primary Use: A thickening agent in sauces, gravies, and soups prepared at home.
Processing: Extracted and purified starch from the endosperm of the corn kernel via wet milling.
Additives: No industrial additives are included in its production.
Nutritional Profile: Composed almost entirely of carbohydrates, lacking the fiber, protein, and micronutrients of whole corn flour. It has a high glycemic index.

Modified Maize Starch (Group 4)

Primary Use: Enhances texture, stability, and shelf life in commercial food products like sauces, dressings, yogurts, and instant foods.
Processing: The plain starch is further altered chemically, physically, or enzymatically to withstand high heat, freezing, or pH changes.
Additives: The modification process itself and its use in final products often involve industrial additives.
Nutritional Profile: Similar to plain starch but designed for different food manufacturing functionalities. Its presence in a product signals extensive industrial formulation.

Comparison of Starch Types


Feature	Plain Maize Starch	Modified Maize Starch	Whole Corn Flour
NOVA Group	Group 2: Processed Culinary Ingredient	Group 4: Ultra-Processed Food Ingredient	Group 1: Minimally Processed Food
Processing	Wet milling to separate endosperm starch.	Further chemical, physical, or enzymatic alteration.	Grinding whole corn kernels.
Additives	None added during production.	Often includes additives to alter properties.	None, as it's a whole food product.
Nutritional Profile	Refined carbohydrate; no fiber, protein, or significant vitamins/minerals.	Highly refined carbohydrate; often in products with low nutrient density.	Contains fiber, protein, vitamins, and minerals from the whole kernel.
Typical Use	Home cooking thickener for sauces and soups.	Industrial thickener/stabilizer in processed foods.	Baking, breading, and culinary applications.

The Role of Maize Starch in Other UPFs

Even though plain maize starch is not a UPF itself, its function as a low-cost, neutral-flavored thickener and binder makes it a common ingredient in many UPF products. When you find it on an ingredient list alongside flavorings, emulsifiers, and preservatives in a packaged snack or ready-meal, it is contributing to the final product's ultra-processed nature. The key takeaway is that the presence of maize starch doesn't make a food a UPF; the entire formulation and level of industrial processing are what ultimately matters.

Conclusion

In summary, the question "Is maize starch upf or not?" has a nuanced answer. Plain maize starch is a processed culinary ingredient (NOVA Group 2), not a UPF. It is made through a rigorous industrial wet-milling process that separates the starch component. However, modified maize starch is a different story, falling into the UPF category due to further chemical or enzymatic alterations. Crucially, plain maize starch is often used as an ingredient in other UPFs, contributing to their formulation without being a UPF itself. To avoid ultra-processed foods, the best approach is to check the entire ingredient list for unfamiliar substances and additives. A standard box of maize starch for home cooking is not the issue; it is the finished, heavily formulated products that are the primary concern for health. For more on the production process, see the Wikipedia article on Corn Starch.

Frequently Asked Questions

Plain maize starch is a processed culinary ingredient created by separating the starch from the corn kernel. Modified maize starch is further processed chemically or physically to alter its properties, classifying it as an ultra-processed ingredient.

According to the NOVA classification, plain maize starch is a processed culinary ingredient, not a UPF. This is because its industrial processing separates components but does not add the numerous industrial cosmetic additives, like emulsifiers and flavor enhancers, that define UPFs.

Yes. Plain maize starch is frequently used as a thickener or binder in many ultra-processed food products, such as packaged snacks and ready-meals, alongside other industrial ingredients.

Plain maize starch is a refined carbohydrate with very little nutritional value, containing almost no fiber, protein, vitamins, or minerals. It has a high glycemic index, meaning it can cause a rapid increase in blood sugar.

No. Whole corn on the cob is a minimally processed food. Other corn products, like corn flour made from grinding the entire kernel, are also less processed than maize starch.

Look at the full ingredient list. If the product contains many other ingredients you wouldn't find in a home kitchen, such as flavorings, emulsifiers, and preservatives, it is likely an ultra-processed food, regardless of the maize starch content.

The NOVA system is a food classification system that groups foods based on the extent and purpose of their industrial processing, ranging from unprocessed (Group 1) to ultra-processed (Group 4).