Astaxanthin from Haematococcus pluvialis Microencapsulated by Spray Drying: Characterization and Antioxidant Activity

Abstract

Astaxanthin (AX) is an unstable functional food ingredient. A stable AX powder was developed and its characteristics (such as moisture content, bulk density, solubility, repose angle, and morphology) and antioxidant activity were evaluated. The microencapsulated AX powder was produced by spray drying using maltodextrin (MD)-gelatin and the parameters were optimized by response surface methodology. The results revealed that an optimal microencapsulation process has a ratio of MD to gelatin of 2.1:1, a ratio of wall to core materials of 5.9:1, and a ratio of glycerol monostearate to sucrose fatty-acid ester of 1.1:1. The AX encapsulation yield and encapsulation efficiency were 38.02% and 71.76%, respectively. AX microcapsules had a lower moisture content and bulk density, greater solubility, and good flowability. AX microcapsules showed antioxidant activities greater than Vitamin C, which indicated that the antioxidant activity of AX was not lost. AX microcapsule micrographs showed almost no cracks or fissures on the surface of microcapsules produced by spray drying under the optimal conditions.

Entrapment of natural compounds in spray-dried and heat-dried iota-carrageenan matrices as functional ingredients insurimigels

“…Besides acting as a carrier, microcapsules prepared by spray drying are known to improve the solubility of the bioactive compounds encapsulated. Similarly high water solubility was found by Zhao et al 26 for spray-dried gelatin-dextrose microcapsules encapsulating astaxanthin (96.2%) and by Venil et al 27 for spray-dried κ-carrageenan microcapsules containing a flexirubin-type pigment (91.6%). It should be noted that no extra-compound was added to the formulation to favour the crosslinking of iota-carrageenan, which could explain the high water solubility values of spray-dried microcapsules.…”

Recent Advances in Astaxanthin Micro/Nanoencapsulation to Improve Its Stability and Functionality as a Food Ingredient

“…The need for specific release conditions or specific release rates is another factor affecting the selection of the encapsulation method and the wall material. Drug release from a polymer matrix can be categorized in three main processes or systems [ 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 , 100 , 101 , 102 ]: (1) diffusion from the non-degraded polymer (diffusion-controlled system); (2) enhanced drug diffusion due to polymer swelling (swelling-controlled system); (3) release by polymer degradation and erosion (erosion-controlled system). Generally speaking, the release velocity will follow the order 3 > 2 > 1.…”

“…The main drawbacks of this ingredient are that pure astaxanthin needs to be used for proper inclusion complex formation and that the astaxanthin:β-cyclodextrin optimum ratio to form the complexes is very high (1:200), thus hindering its applications in the food sector. On the other side, it is spray-drying, which is a widespread cost-effective drying method in food industries that have been assayed for the encapsulation of astaxanthin extracts from both microalgae or shrimp by-products with good results at improving functionality [ 57 , 58 , 60 , 78 , 79 , 92 , 93 , 94 , 95 ]. This process also has the advantage, as compared with cyclodextrin inclusion complexation, of upgrading the whole ingredient, avoiding any additional separation steps.…”

Astaxanthin and other Nutrients from Haematococcus pluvialis—Multifunctional Applications

“…Studies on rats showed an increase in the content of antioxidant enzymes, such as catalase, superoxide dismutase and glutathione peroxidase after cyclic dosing of astaxanthin [ 116 , 124 ]. Astaxanthin has the status of pure antioxidant, which means that it does not have any pro-oxidative properties [ 129 ]. The main obstacle to the industrial use of astaxanthin is its low chemical stability during storage.…”

“…The microcapsules showed good spherical shapes with a smooth surface and good solubility. The use of cheap carriers makes the process economically profitable [ 129 ].…”