Endogenous wheat enzymes: natural keys to stronger gluten and better bread

The study highlights the catalytic roles of enzymes such as sulfhydryl oxidase (SOX), protein disulfide isomerase (PDI), ascorbate oxidase (AAO) , and dehydroascorbate reductase (DHAR) in promoting disulfide and covalent bond formation within gluten proteins. By clarifying their molecular mechanisms, the review demonstrates how natural enzymatic processes can replace chemical oxidants, paving the way for safer “clean label” wheat-based foods with improved elasticity, stability, and sensory qualities.

Wheat is one of the world’s most widely cultivated crops, prized not only for its nutritional value but also for its unique ability to form viscoelastic dough. This property is primarily governed by gluten proteins—gliadins and glutenins—whose structure and interactions determine dough extensibility, elasticity, and gas-holding capacity. Traditionally, breadmaking has relied on chemical oxidants like potassium bromate to enhance gluten strength, but safety concerns and consumer demand for natural products have accelerated interest in endogenous enzymatic alternatives. In this context, researchers overview the catalytic systems already present in wheat itself—enzymes capable of catalyzing thiol–disulfide exchanges, redox reactions, and cross-linking processes. These naturally occurring enzymes not only enhance dough and bread quality but also align with industry efforts toward sustainability and clean processing. Based on these challenges, there is a pressing need to explore endogenous enzyme systems as safe and effective substitutes for chemical improvers.

A study (DOI: 10.48130/fia-0025-0030) published in Food Innovation and Advances on 24 July 2025 by Jinshui Wang’s team, Henan University of Technology, concludes that endogenous enzymes regulate gluten cross-linking through diverse redox and covalent bond-forming mechanisms, directly shaping dough performance and bread quality.

This review provides a systematic exploration of the four central enzyme families in wheat. SOX catalyzes thiol oxidation, strengthening gluten networks and producing hydrogen peroxide that can further enhance cross-linking. PDI ensures proper protein folding by rearranging mispaired disulfide bonds, thus stabilizing the gluten structure and improving elasticity. AAO and DHAR work together to maintain redox balance: AAO converts ascorbic acid to dehydroascorbate, generating intermediates that form new disulfide bonds, while DHAR recycles dehydroascorbate back to ascorbic acid to sustain antioxidant capacity. Beyond these, other enzymes—tyrosinase, laccase, peroxidase, catalase, lipoxygenase, lipase, and NAD(P)H-dependent dehydrogenases—contribute additional layers of protein and polysaccharide cross-linking. Collectively, these enzymes modulate gluten’s physicochemical state, influencing dough viscoelasticity, loaf volume, and crumb texture. Importantly, the review emphasizes that the natural enzyme system in wheat provides a theoretical foundation for clean-label strategies, as it minimizes the risks associated with exogenous chemicals. The authors also highlight the role of emerging technologies, such as artificial intelligence-based protein modeling (e.g., AlphaFold2 and generative design tools), which may accelerate the rational design of enzyme variants tailored for industrial baking conditions. By mapping both catalytic pathways and practical applications, the review integrates molecular biology, food chemistry, and processing technology into a coherent framework for wheat improvement.

In summary, this review underscores that endogenous wheat enzymes hold untapped potential for naturally enhancing dough and bread quality. Their ability to promote gluten cross-linking, maintain redox balance, and stabilize protein networks provides a safer, more sustainable alternative to chemical improvers. For the food industry and consumers alike, endogenous enzymes represent a promising path toward safer, higher-quality, and clean-label wheat products.

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References

DOI

10.48130/fia-0025-0030

Original Source URL

https://doi.org/10.48130/fia-0025-0030

Funding information

This work was supported by the Joint Fund of Science and Technology Research and Development Plan of Henan Province in 2022 (225200810110); Scientific and Collaborative Innovation Special Project of Zhengzhou, Henan Province (21ZZXTCX03); Youth teachers in colleges and universities of Henan province fund (2023GGJS061); Special Funds to Subsidize Scientific Research Projects in Zhengzhou R&D (22ZZRDZX34); and the open project program of the National Engineering Research Center of Wheat and Corn Further Processing, Henan University of Technology (NL2022016).

About Food Innovation and Advances

Food is essential to life and relevant to human health. The rapidly increasing global population presents a major challenge to supply abundant, safe, and healthy food into the future. The open access journal Food Innovation and Advances (e-ISSN 2836-774X), published by Maximum Academic Press in association with China Agricultural University, Zhejiang University and Shenyang Agricultural University, publishes high-quality research results related to innovations and advances in food science and technology. The journal will strive to contribute to food sustainability in the present and future.