Energy and Quality Aspects of Freeze-Drying Preceded by Traditional and Novel Pre-Treatment Methods as Exemplified by Red Bell Pepper

Freeze-drying is one of the most expensive and energy intensive processes applied in food technology. Therefore, there have been significant efforts to reduce freeze-drying time decrease its consumption. The aim this work was analyze effect pulsed electric field (PEF), ultrasound (US), hybrid treatment (PEF-US) compare them with blanching (BL) on kinetics, consumption, greenhouse gasses emission, physical quality product. process red bell peppers after pretreatment operations. Results showed that application BL, PEF, US, or PEF-US reduces decreases Among tested methods, combination PEF performed at 1 kJ/kg US effective reduction gas emission. BL samples exhibited highest porosity, but from a statistical point view, treated materials did not differ it. smallest color changes were noted for pre-treated (?E = 9.4), whereas material characterized by ?E 15.2–28.5. Performed research indicates pre-treatment may improve sustainability freeze-dried pepper.