Nanoencapsulation of phycocyanin extracted from the alga Spirulina (Spirulina platensis) and use of nanoparticles in ice cream formulation

Due to the concerns about the use of artificial colors in various foods, it is necessary to pay attention to sources with natural colors. One of these sources is the algae Spirulina, which contains the blue pigment phycocyanin. The aim of the present study in the first stage was to extract this pigment from the algae by enzymatic method and its nanoencapsulation. In the second stage, the physicochemical properties of nanoparticles were investigated. Finally, phycocyanin in both free and nano forms was added to the ice cream formulation and the qualitative and sensory properties of the product were evaluated in comparison with the control. The results showed that the produced nanoparticles have an average size of 397.1 nm. The encapsulation efficiency of the process was recorded 73.41%. According to the images recorded using scanning electron microscopy, the nanoparticle with different dimensions are scattered in the microscopic spread so that the particles are visible in different sizes. The release results of nanoparticles in vitro showed that at pH=1.2, the release percentage of phycocyanin is low (the first 2 hours). So that it fluctuates in the range of 7 to 13%. But after this stage (pH=7.4), the release rate increased significantly and from 35 to 71% at 3 and 4 hours, respectively. The use of pure phycocyanin in ice cream formulation improved the hardness, melting percentage, texture, hardness, crystalline intensity and coldness. But these indices were reported at a more favorable level in the treatment formulated with nanoencapsulated phycocyanin. The color index in ice cream formulated with pure phycocyanin was more desirable and more acceptable compared to the treatment with nanoencapsulated phycocyanin. Due to the properties of phycocyanin, especially the nanoencapsulated form, it can be used as a biological dye and improver the quality and sensory properties in various ice creams.