Optimization of Almond Beverage Enriched with Omega-3 Fatty Acids by Adding Brown Flaxseeds (Linum usitatissimum L.) Using D-Optimal Mixing Diagram Method.

Research background: The almond beverage enriched with flaxseed is an important source of α-linolenic acid (ALA), an essential omega-3 fatty acid that the human body cannot synthesize and must obtain it through the diet. Although omega-3 fatty acids are essential for all people, this beverage is particularly beneficial for those who do not consume fish, such as vegans and vegetarians, as it is a plant-based source of ALA. Its versatility allows it to be easily incorporated into different recipes and daily meals. Therefore, this study aims to optimize a plant-based almond beverage enriched with flaxseed, offering a natural and completely vegan source of omega-3 fatty acids.

Experimental approach: The initial formulation of the drink comprised 75 % raw almonds and 25 % flaxseed mixture, water (in 1:6 ratio) and 4 % sweetener. Following preliminary tests, the beverage was optimized using the mixing method to determine the ideal proportions of the ingredients. This process resulted in 16 samples, each with different minimum and maximum amounts of each ingredient, which were replicated and analyzed. One of the formulations achieved an optimal mass fraction of 4.27 mg/g of omega-3 fatty acids and a viscosity of 6.03 mPa^.s. The physicochemical properties, bioactive compounds, fatty acid composition and lipid profile of the optimized beverage were evaluated.

Results and conclusions: The addition of flaxseed had a significant effect on the lipid profile and increased the alpha-linolenic acid content in the beverage by 1960 times, eventually reaching 3.92 %. This optimization enriched the beverage with omega-3 fatty acids and improved the concentration of antioxidants and carotenoids. Importantly, these improvements did not significantly affect the color and viscosity of the final product, creating an affordable option that can benefit the vegan and vegetarian community.

Novelty and scientific contribution: This study shows that the response surface model effectively identified the ideal composition for the beverage, leading to an optimized formulation of a plant-based drink. This composition could have promising applications in the food industry.