Lactic acid bacteria-fermented Chlamydomonas reinhardtii as an innovative ingredient to produce microalgae-enriched steamed bread

Background and Objectives

Chlamydomonas reinhardtii (C. reinhardtii) is recognized as a sustainable source of high-quality protein. This study aimed to assess the potential application of C. reinhardtii for producing microalgae-fortified steamed bread. To reduce the inherent green color and volatile compounds of the microalgae, lactic acid bacteria (LAB) fermentation was applied as a pretreatment method for C. reinhardtii. Subsequently, both unfermented (unFC) and fermented C. reinhardtii (FC) were added to steamed bread formulations (4%, 8%, 12%, and 16% wheat flour substitution).

Findings

The results showed that the incorporation of unFC into steamed bread had a dose-dependent negative impact on the dough fermentation performance and the quality of steamed bread, including volume, texture, and sensory attributes, rendering the steamed bread unacceptable. Fermentation altered the amino acid profile of C. reinhardtii, caused the color to shift from green to red (a*, −14.7 vs. 7.0), and reduced unpleasant volatile components. Further, fermentation reduced the negative impact of microalgae incorporation, especially at substitution levels of 4% and 8%, which manifested as an increased dough fermentation volume and improved bread volume with reduced crumb firmness of the steamed bread. However, in sensory analysis, the steamed bread that contained 4% FC had an overall acceptability similar to the control sample.

Conclusions

Microalgae-enriched steamed bread could be produced by incorporating up to 4% FC to improve its nutritional profiles while maintaining overall sensory acceptability by the consumers.

Significance and Novelty

LAB fermentation of C. reinhardtii is a feasible strategy to address the sensory and structural challenges that hinder the incorporation of algae into food products.