Phenolic compounds in quinoa and amaranth grains: Composition, biological properties and processing effects

Area of Science:

• Nutritional Science
• Food Chemistry
• Agricultural Science

Background:

• Quinoa and amaranth are recognized as 'super-grains' due to their rich phenolic content, including phenolic acids and flavonoids.
• These phenolic compounds are associated with significant health-promoting properties, such as antioxidant, antihyperglycemic, and anti-inflammatory activities.
• Genetic diversity exists within quinoa and amaranth species, influencing their distinct phenolic profiles.

Purpose of the Study:

• To investigate the phenolic profiles of quinoa and amaranth grains.
• To understand the impact of various processing methods on these phenolic compounds and their biological functions.
• To identify challenges and propose future directions for research on these grains' phenolics.

Main Methods:

• Analysis of free and bound phenolic compounds in quinoa and amaranth grains.
• Evaluation of genetic diversity and similarities in phenolic profiles across different species and genotypes.
• Assessment of how processing techniques (e.g., germination, fermentation, roasting, boiling, extrusion, microwave, radiation) alter phenolic content and biological activity.

Main Results:

• Significant genetic diversity and similarities were observed in the phenolic profiles of quinoa and amaranth species.
• Phenolic compounds in these grains demonstrated notable antioxidant, antihyperglycemic, and anti-inflammatory properties.
• Processing methods significantly altered the phenolic profiles and associated biological functions of the grains.

Conclusions:

• Phenolic compounds are key contributors to the nutritional value and health benefits of quinoa and amaranth.
• Processing methods require careful consideration as they can modify the phenolic composition and bioactivity.
• Standardized methodologies for extraction, quantification, and in vivo/clinical studies are crucial for advancing the food and nutritional applications of quinoa and amaranth phenolics.