Effect of various culinary treatments on the glycoalkaloid content of potato peel

Potatoes are one of the most consumed foods worldwide. During germination, glycoalkaloids (GAs) with potential bioactive properties are produced, which, at high concentrations, may have adverse health effects. Potato peels, a byproduct generated in large quantities but increasingly used in contemporary cuisine, contain significant levels of these GAs. This paper examines GA levels in potato peels after various culinary treatments (boiling, steaming, baking, air frying, conventional deep frying, and double frying) to provide new data and ensure food safety. An optimized extraction method using ultrasound-assisted extraction (UAE) was employed, followed by purification with mesostructured SBA-15 silica functionalized with octadecylsilane (C18) chains as sorbent in solid-phase extraction, prior to HPLC-DAD determination of alpha-solanine and alpha-chaconine levels in the samples. The method was validated, obtaining excellent recovery values (88 - 96 %) and low detection and quantification limits (0.3 and 1 mg/L, respectively). Upon application of the validated analytical method to the samples culinarily treated using the most common cooking techniques (boiling, steaming, baking, air frying, conventional deep frying, and double frying) at various times and temperatures, the obtained results demonstrated significant reductions (between 52 % and 84 %) in GAs content in the treated potato peels, compared to fresh samples. Statically significant degradation of these compounds was observed through baking at elevated times and temperatures (74 - 84 %), as well as both conventional deep frying and double frying (76 - 83 %).