A comparative evaluation of conventional, microwave and hybrid baking methods and their impact on bread quality, acrylamide formation and sustainability

Abstract

This study investigated the effects of conventional baking (CB), domestic microwave (DM), industrial solid-state microwave (IM), and hybrid baking approaches on the physicochemical properties, acrylamide formation, energy consumption, and environmental impact of bread. The results revealed that across an eight-day storage period, moisture content decreased significantly in all samples; however, IM breads retained the highest moisture, resulting in the lowest hardness values and slower staling, while DM breads showed the greatest moisture loss and firmness. Crust colour varied significantly with heating mode with CB breads produced the darkest crust due to increased Maillard reactions while IM and DM breads exhibited lighter crusts because of lower surface temperatures. Specific volume was highest in CB breads, with microwave-only breads exhibiting reduced expansion due to rapid internal heating, though hybrid methods partially mitigated this effect. Crumb microstructure analysis showed that IM and DM breads developed larger and more irregular cells compared to CB breads, because of the distinct heating patterns and pressure gradients produced by microwave systems. Acrylamide concentrations were significantly lower in all microwave and hybrid treatments than in CB samples, because of reduced surface browning and shorter exposure to high-temperature, low-moisture conditions. Overall, industrial solid-state microwave baking demonstrated lower energy consumption and improved environmental sustainability while producing bread with reduced acrylamide formation and acceptable quality, highlighting its strong potential for sustainable industrial baking applications.