The Prevention of Food Adulteration Act of 1954 defines "adulterated" food as follows in Section 2(a)-

• If the purchased food does not meet the customer's expectations for substance, quality, or nature.
• A food product can also be considered contaminated if it differs from the substance, nature, or quality that was previously represented.
• Whenever a food item contains a material or ingredient of low quality that could have an impact on the consumer's health.
• Therefore, any food item packed, processed, or maintained in unclean or filthy conditions will be contaminated.
• In the event where a food item is obtained from a dead animal.
• If the aforementioned food item is entirely or partially rotten, decaying, unclean, or manufactured from a sick animal.
• If the vegetable contains pesticides or insecticides or is in any other manner unfit for human consumption.
• Food products with any potentially harmful ingredients, such as those that are poisonous, noxious, or corrosive.
• Any food product that uses a prohibited preservative or an allowed preservative in excess of the permitted amount
• If the food item's quality falls short of the standards set out or contains substances that exceed what is acceptable.
• Any other reasons mentioned.
However, it won't be considered food adulteration if the purity or quality of the food item is compromised due to any natural causes. Additionally, the exhibition of any deceptive or confusing advertising intended to promote the sale of any food item is included in the definition of "food adulteration."