Investigation of Bioavailability and Food-Processing Properties of <i>Arthrospira platensis</i> by Enzymatic Treatment and Micro-Encapsulation by Spray Drying

Abstract

Due to its high-protein content of 60–70% on dry weight, Arthrospira platensis, has been considered as one of the most sought-after protein alternatives. However, the processing of Arthrospira platensis extract (spirulina, SP) in food is usually limited due to the strong green colour and taste, as well as the lack of bioavailability of plant proteins. Therefore, this study aimed to increase its use in food applications through technologies such as microencapsulation by spray drying and enzymatic treatment. The effect of different combinations of maltodextrin (MD) and gum arabic (GA) as coating material were tested in ratios of 1:2 and 1:4 for Arthrospira platensis, core to wall material, respectively. Additionally, enzymatic treatment was used to investigate whether digestibility, protein solubility and powder solubility can be improved. Thermal stability was examined by differential scanning calorimetry (DSC), and colour intensity was analysed over L* a* b* colour system. The sample SP-MD1:2 showed the highest heat stability with a denaturation peak at 67 °C, while the samples SP-MD1:4 and ESP-MD1:4 revealed the best brightening effects. The crude protein content stated by the manufacturer of 67% was confirmed. Encapsulation and enzymatic hydrolysis enhance the protein solubility, under which ESP-MD1:4 had the greatest solubility at around 83%. The protein digestibility peaks were around 99% with sample SP-MD1:2.

Keywords

• <i>Arthrospira platensis</i>
• microencapsulation
• enzymatic treatment
• digestibility
• protein solubility
• differential scanning calorimetry