Background: Silicon dioxide (SiO) and titanium dioxide
(TiO) are ones of the most widely used food additives as an anti-caking and
a coloring agent, respectively, in the food industry. Understanding particle,
aggregate, or ionic fates of two additives in commercial products is of
importance to predict their potential toxicity. Methods: Triton X-114
(TX-114)-based cloud point extraction (CPE) methods for two additives were
optimized in food matrices. Their particle or ionic fates in various commercial
foods were determined by the CPE, and the physico-chemical properties of
separated particles were further characterized. Results: SiO and
TiO were primarily present as particle forms without changes in constituent
particle size, size distribution, and crystalline phase. The maximum solubilities
of SiO and TiO were 5.5% and 0.9%, respectively, depending on food
matrix type, supporting their major particle fates in complex food matrices.
Conclusions: These findings will provide basic information about the
fates and safety aspects of SiO and TiO additives in commercial
processed foods.