Technological and Quality Features of Gluten Free Sponge Cakes Baked by Combined Ohmic-Hot Air System

Abstract

This work aimed to study the combined baking of a gluten-free sponge cake using an ohmic system and a hot air system. A temperature-resistant silicone mold was modified to hold the ohmic cell; two parallel stainless-steel electrodes were mounted across the width of the mold, with a 9 cm gap. Series baking tests used a first ohmic stage, followed by a hot-air stage in an electrical oven for 5 or 10 min at 180°C or 220°C. Simultaneous baking tests were performed in a hot air toaster oven for 5 or 10 min at 180°C or 200°C, with the ohmic system switched on for the first 3 min. As a control, traditional baking was performed for 20 min at 180°C. The cake was evaluated for various technological (baking time, energy consumption, efficiency) and quality characteristics (surface color, weight loss, moisture content, crumb density, height, hardness, cohesiveness, elasticity). Compared to conventional baking, the use of ohmic baking reduces the baking time from 20 to 5 min and specific energy consumption from 10,727 to 5075 kJ/kg, providing higher and less dense products, but crustless, colorless surfaces and drier. The series baking allows improving crust formations and surface color, but high weight loss remains. The simultaneous baking allows keeping weight loss controlled. In all cases, instrumental texture properties were not significantly different. The results showed the potential application of ohmic technology for fast and energy-efficient industrial baking, and how to solve deficiencies related to crustless and colorless characteristic product surfaces.