Functional role of citrus fiber as an emulsifier in dough rheology, gluten structure formation and bread quality characteristics.

Citrus fiber (CF) is a promising clean label emulsifier to replace commonly used emulsifiers such as propylene glycol alginate (PGA) in breadmaking. However, most previous studies have focused primarily on the physical and sensory attributes of CF-enriched bread while the mechanisms underlying these effects remain poorly understood. The addition of CF significantly increased β sheet structure of gluten proteins and improved both the storage modulus (G') and loss modulus (G″) of dough, with a more pronounced effect on G' compared to PGA. White bread containing the optimum CF level (0.6% CF) displayed the highest specific loaf volume, improved crumb structure and reduced staling, whereas a higher level (0.9%) led to a decline in bread quality. Quantitative protein network analysis indicated that CF enhanced dough properties by increasing total gluten length, area and junction density. Overall, CF demonstrates potential as a clean label functional ingredient that improves the structural and textural quality of bread for health-conscious consumers. However, its optimal incorporation level must be carefully controlled to avoid adverse effects on product quality.