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BACKGROUND: Energy‐saving and low‐carbon baking processes, as well as the need to determine the flavor‐forming mechanisms of baked dried tofu, are becoming increasingly necessary. The application of emerging catalytic infrared radiation (CIR) technology in baking of dried tofu is considered of high interest due to the low energy consumption and high baking efficiency compared to traditional baking methods. Hence, this study aimed to investigate the evolution of aroma compounds in baked dried tofu during the CIR baking process and reveal relevant relationships between physical qualities, potential flavor precursors and key volatile compounds. RESULTS: The results showed that the surface color of dried tofu gradually turned an appetizing golden yellow color during the rapid heating process, caused by the uniform infrared radiation from the radiant emitters. Meanwhile, the moisture of dried tofu experienced minimal reduction and the hardness of dried tofu gradually increased with the formation of crust on the surface. In addition, 49 volatile compounds were identified by headspace solid‐phase microextraction–gas chromatography–mass spectrometry and 13 substances – 1‐hexanol, 1‐octen‐3‐ol, 1‐pentanol, heptanal, nonanal, hexanal, (E,E)‐2,4‐decadienal, (E,Z)‐2,4‐decadienal, octanal, (E)‐2‐octenal, (E)‐2‐nonenal, 2‐heptanone and 2‐pentylfuran – were confirmed as key aroma compounds. Moreover, the amino acids aspartic acid, glutamic acid, isoleucine, lysine and arginine, and the fatty acids butyric, caprylic, capric, tridecanoic, stearic, oleic and linolenic were responsible for the unique flavor of CIR‐baked dried tofu. CONCLUSION: Consequently, the findings can provide a scientific basis for manufacturers to achieve precise quality control and large‐scale production of CIR‐baked dried tofu products. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this study, effects of conveyor belt catalytic infrared radiation (BCIR) baking on sensory, surface color, texture, microbial sterilization, soy isoflavone, and water distribution were investigated comprehensively. The parameters of BCIR were radiation distance (12, 15, and 18 cm), baking temperature (65 °C, 80 °C, and 95 °C), and the corresponding speed of conveyor belt (0.58, 0.41, 0.28, 0.67 m/min, etc.). Meanwhile, the effect of conventional hot air (HA) baking on dried tofu were also studied for comparison. The results showed that the impact of BCIR radiation distance on the quality of the baked dried tofu was greater than that of baking temperature. In addition, there was a correlation between the moisture indexes and quality indicators of dried tofu under different BCIR baking temperatures and radiation distances. In comparison to HA baking, BCIR was better in golden-brown level, appealing sensory, microbial safety. Meanwhile, BCIR not only shortened the total baking time but also saved energy in scaled production of baked dried tofu. Conveyor belt catalytic infrared radiation (BCIR) baking, an emerging thermal processing technique at the pilot scale, was innovatively employed in dried tofu baking for its prompt attributes of high efficiency and energy-saving in this study. The findings of the current research explored the physicochemical qualities and water distribution subjected to BCIR treatment, with the comparison of traditional hot air baking, which can provide basis and assistance for the BCIR application in the food baking industry and for scaling up the baking process with energy-saving production. • Dried tofu was baked by a conveyor belt catalytic infrared radiation (BCIR) apparatus. • The quality of baked dried tofu products by BCIR can be equivalent to or higher than hot air. • The water distribution and migration principle of baked dried tofu by BCIR were first discovered. • Appropriate BCIR baking process parameters of dried tofu were determined. [ABSTRACT FROM AUTHOR]