Enhancing Chia Seed Protein Extraction: Impact of Defatting and Optimization of Functional Properties

Aim:

This study aims to compare the efficiency of protein extraction from chia seeds (Salvia hispanica L.), with a specific focus on the influence of different defatting processes. Traditional defatting methods, such as the use of solvents like hexane or ethanol, are commonly recommended and generally regarded as safe. However, due to growing environmental and sustainability concerns, there is increasing interest in exploring more eco-friendly alternatives, such as supercritical CO2 extraction. The objective is to evaluate the effectiveness of each defatting method in terms of protein yield and their potential applications in the food industry, while considering their impact on functional properties.

Method:

Chia seeds were subjected to four distinct fat extraction methods:

No defatting (control)

Mechanical defatting

Defatting using supercritical CO2 with ethanol

Conventional defatting with hexane

Following defatting, the protein extraction processes were optimized for each method. The extracted proteins were then analyzed for yield and functional properties, including solubility, emulsifying capacity, stability, and water/oil holding capacities, to assess their suitability for food industry applications.

Result:

Preliminary trials have shown significant variations in protein yield and functional properties across the different extraction and defatting methods. Protein yields from personal trials ranged between 27% and 45%, while literature reports yields between 73% and 79% depending on the method used. Functional properties also varied significantly:

Solubility: 39-56%

Emulsifying capacity: 161-203%

Oil holding capacity: 186-474%

Water holding capacity: 235-753%

These variations suggest that the choice of defatting method has a substantial impact on both protein yield and functional characteristics.

Conclusion:

The study highlights the potential benefits of alternative fat extraction methods for improving protein yield and functional properties from chia seeds. Supercritical CO2 extraction and mechanical defatting methods showed particularly promising results compared to conventional hexane-based approaches. These methods not only maximize protein yield but also enhance functional properties, which could have significant implications for food product development and formulation. Further research is needed to optimize these alternative extraction techniques for industrial-scale application and fully realize their environmental and economic benefits.