EVALUATION OF THE NANOENCAPSULATION EFFECT ON SOLUBILITY, ANTIOXIDANT AND ANTIMICROBIAN POTENCIAL OF PIGMENTED WITH ASTAXANTHIN FROM SHRIMP WASTE FLOUR (Litopeneaus vannamei)
Antioxidants, nanoparticles, óleo vegetal
The white shrimp (Litopenaeus vannamei) is one of the most economically important marine species and its processing produces inappropriately discarded waste. Therefore, its reuse has the potential to contribute to the formulation of products for the food industry and reduce environmental impact. Astaxanthin is the main carotenoid found in shrimp and has high antioxidant power. The viability of the carotenoid is lost during thermal processing, oxidation or storage, thus causing it to lose its biological capacity. Encapsulation is an effective technique for protecting bioactive compounds such as astaxanthin. The aim of this study was to encapsulate astaxanthin-pigmented oil with porcine gelatine and soy protein isolate, or a combination of these, to improve the bioactive properties of the pigmented oil. The encapsulation technique used was oil/water (O/W) emulsification, using porcine gelatine and soy protein as encapsulating agents and Tween 20 as a surfactant. The formulations developed: oil pigmented with astaxanthin encapsulated in porcine gelatine (EAG), oil pigmented with astaxanthin encapsulated in soy protein (EAS), oil pigmented with astaxanthin encapsulated in porcine gelatine and soy protein in the ratio 2:2 w/w (EAGS 2:2) and in the ratio 3:1 w/w (EAGS 3:1). The particles were characterized using Scanning Electron Microscopy (SEM), Dynamic Light Scattering (DLS), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR), Incorporation efficiency (IE) and dispersion in water were also evaluated. The EAS formulation leaked oil and did not follow the characterization steps. The formulations were spherical in shape, with a smooth surface and no cracks or depressions based on the micrographs. The average sizes by DLS were 159.68 (14.42) nm for EAG, 1004.97 (151.10) nm for EAGS 2:2 and 95.41 (17.83) nm for EAGS 3:1. The encapsulates showed attenuation of the amorphous structure based on the XRD. FTIR showed accentuated O-H and C-H stretching bands (3314 cm-1, 3291cm-1, 3318cm-1) in EAG, EAGS 2:2 and EAGS 3:1, respectively, revealing intramolecular bonds between astaxanthin-pigmented oil and the materials used. Dispersibility in water showed values of 56.25%±3.04 (EAG), 52.21%±4.78 (EAGS 2:2) and 58.07%±3.53 (EAGS 3:1) and EI reached 91.99% (EAG), 91.12% (EAGS 2:2) and 92.02% (EAGS 3:1). From the results obtained, the wall materials porcine gelatine and/or combination with soy protein were effective for encapsulating the oil pigmented with astaxanthin, since they increased solubility, high IE and thermal stability, characteristics that make incorporation into food matrix viable.