Yogurt Enriched with Isochrysis galbana: An Innovative Functional Food

Microalgae are a valuable and innovative emerging source of natural nutrients and bioactive compounds that can be used as functional ingredients in order to increase the nutritional value of foods to improve human health and to prevent disease. The marine microalga Isochrysis galbana has great potential for the food industry as a functional ingredient, given its richness in omega 3 long chain-polyunsaturated fatty acids (LC-PUFAs), with high contents of oleic, linoleic, alpha-linolenic acid (ALA), stearidonic, and docosahexaenoic (DHA) acids. This study focuses on the formulation of a functional food by the incorporation of 2% (w/w) of I. galbana freeze-dried biomass and 2% (w/w) of I. galbana ethyl acetate lipidic extract in solid natural yogurts preparation. In the functional yogurt enriched with microalgal biomass, the omega 3 LC-PUFA's content increased (to 60 mg/100 g w/w), specifically the DHA content (9.6 mg/100 g ww), and the omega 3/omega 6 ratio (augmented to 0.8). The in vitro digestion study showed a poor bioaccessibility of essential omega 3 LC-PUFAs, wherein linoleic acid (18:2 omega 6) presented a bioaccessibility inferior to 10% and no DHA or eicosapentaenoic acid (EPA) was detected in the bioaccessible fraction of the functional yogurts, thus indicating a low accessibility of lipids during digestion. Notwithstanding, when compared to the original yogurt, an added value novel functional yogurt with DHA and a higher omega 3 LC-PUFAs content was obtained. The functional yogurt enriched with I. galbana can be considered important from a nutritional point of view and a suitable source of essential FAs in the human diet. However, this needs further confirmation, entailing additional investigation into bioavailability through in vivo assays.

Automated summary

Microalgae, such as Isochrysis galbana, are being explored as a valuable source of natural nutrients and bioactive compounds for functional food applications. This study demonstrated that incorporating I. galbana biomass and lipid extract into yogurt can significantly increase the omega 3 LC-PUFAs content, particularly DHA, making it a potentially important nutritional source. Further research is needed to confirm the bioavailability of these compounds in vivo.