Abstract: This invention relates to the treatment of raw white potatoes previously stored at low temperatures (about 40.degree. to 45.degree. F for periods up to 10 months) to render them suitable for thermal sterilization at about 250.degree. F and for long-term storage in flexible plastic or plastic-aluminum foil laminated containers such as pouches without added liquid. The process comprises; (a) immersion of potatoes, either whole, sliced, diced or in any other convenient form, in an aqueous solution comprising citrate in combination with sulfur dioxide; followed by (b) immersion in an aqueous solution of an alkali metal pyrophosphate and optionally a reducing saccharide; followed by (c) immersion in an aqueous solution of an alkaline earth metal salt and optionally an alkali metal chloride. The so-treated potato product is then packaged in a flexible container and thermally sterilized.