Does the subject want to ask "does potassium sorbate react with starch?" Yes Potassium sorbate will react with protein and starch to produce toxic substances, producing white or white-like powder or granular white or white-like powder or particles. Potassium sorbate is a preservative in food additives and used in food processing. Potassium sorbate is produced by the neutralization reaction of sorbic acid and potassium carbonate, which has the basic properties of sorbic acid.