Ultrasonically extracted flaxseed mucilage: an effective egg substitute in gluten-free noodles to enhance cooking quality and reduce energy value.

Background: Flaxseed mucilage is a natural hydrocolloid that can be easily extracted from whole flaxseed or defatted flaxseed meal. It can be used as a thickening, emulsifying, water-retention, suspending and gelling agent to improve the technological features of foodstuffs. Moreover, flaxseed mucilage, as a natural soluble fiber source, has potential health benefits such as regulating gut microbiota, promoting satiety and reducing cholesterol levels. Due to its technological properties and health benefits, it has recently received attention from consumers, producers and researchers. In this study, flaxseed mucilage was extracted from cold-pressed flaxseed meal using conventional and ultrasound-assisted extraction methods. To enhance nutritional quality, solutions of conventionally and ultrasonically extracted flaxseed mucilages were separately used in gluten-free noodles as egg substitutes at 0%, 25%, 50%, 75% and 100% levels. The effects of mucilage type and level on the chemical, technological, textural and sensory quality of noodles were investigated.

Results: Incorporation of sonicated mucilage revealed a firmer texture, lower cooking loss and stronger antioxidant activity in gluten-free noodles compared with conventionally extracted mucilage. Increasing the level of flaxseed mucilage from 0 to 100% reduced fat content and energy value, and enhanced the antioxidant activity of noodles. Substitution of eggs with mucilage (up to 75%) exhibited better cooking quality than 100% egg noodles. Sensorially, the substitution of eggs with sonicated mucilage elicited greater overall acceptability scores.

Conclusion: The results demonstrated that ultrasonically extracted flaxseed mucilage has potential as a natural and sustainable hydrocolloid to replace eggs in the preparation of high-quality and healthy gluten-free noodles. © 2025 Society of Chemical Industry.