Table 1.

Examples of different kinds of nanoscale materials that might be present within foods and their origin

Nanoscale material	Origin	Characteristics	Products
Organic nanoparticles
Casein micelles	Natural	Protein–mineral clusters	Milk, cream
Cell organelles	Natural	Ribosomes, vacuoles, lysosome etc.	Meat, fish, fruits, vegetables, spices
Oil bodies	Natural	Phospholipid/protein-coated triglyceride droplets	Plants, seeds
Lipid nanoparticles	ENP	Solid particles or liquid droplets coated by emulsifiers	Some beverages, sauces, dressings, creams
Protein nanoparticles	ENP	Clusters of protein molecules held together by physical or covalent interactions	Mainly in development
Carbohydrate nanoparticles	ENP	Small solid fragments extracted from starch, cellulose, or chitosan. Clusters of polysaccharide molecules held together by physical or covalent interactions.	Mainly in development
Inorganic nanoparticles
Iron oxide	ENP	FeO nanoparticles used to fortify foods with iron.	Nutritional supplements, sausage casings
Titanium dioxide	ENP	TiO2 nanoparticles used as whitening agents	Candies, chewing gums, bakery goods, milk powders.
Silicon dioxide	ENP	SiO2 nanoparticles used to control powder flowability	Salts, icing sugar, spices, dried milk, and dry mixes
Silver	ENP	Ag nanoparticles used as antimicrobials in foods, coatings and packaging	Meat, food packages, containers, coatings

Key: ENP engineered nanoparticle, which may be intentionally or unintentionally added