Spray‐Drying, Oil Blending, and the Addition of Antioxidants Enhance the Storage Stability at Room Temperature of Omega‐3‐Rich Microcapsules Based on Chia Oil

Abstract

Chia oil (CO) has gained popularity given its 𝜶-linolenic acid content (around 60%). Nonetheless, the susceptibility of polyunsaturated fatty acids toward oxidation represents a challenge for incorporating CO in different products, which justifies the need for exploring stabilization methods. To the best of the authors' knowledge, no reports about powders based on chia oil blends are published. Therefore, the objective of this research is to evaluate the stability at room temperature of microencapsulated CO blends [with virgin sesame (VSO) and wheat germ (WGO) oils] and microencapsulated CO with the addition of tert-butylhydroquinone (TBHQ). Spray-drying yielded powders with a better encapsulation efficiency, flowability, and stability, compared with freeze-drying. After a storage test performed during 3 months, the highest hydroperoxide content (>100 meq.O 2 kg −1 oil) is observed for the microencapsulated CO/WGO 80/20 blend, despite its 𝜶 and 𝜷-tocopherol contents and its antioxidant activity (>90% inhibition of DPPH radical). Notwithstanding, bulk and microencapsulated CO-TBHQ, CO/VSO 80/20, and 20/80 showed hydroperoxide contents <8 meq.O 2 kg −1 oil. By the end of the test, the highest induction period is observed for the microencapsulated CO/VSO 20/80 blend (19.85 ± 0.18 h). Finally, the drying method and the core formulation greatly affect the stability of microcapsules. Practical Applications: Addition of antioxidants, oil blending and microencapsulation are technological solutions for the preservation of omega-3-rich oils, which are popular among healthy food consumers. This research studies and compares the microencapsulation processes by spray or freeze-drying in order to preserve chia oil blends (with virgin sesame and wheat germ oils) and chia oil with the addition of antioxidants, thereby taking the advantages of the three technological solutions mentioned above. Stable omega-3-rich powders, with a higher oxidative stability than pure chia oil, can be obtained as ingredients for the food industry. This ultimately allows the incorporation of the oil into different food products developed to satisfy specific market tendencies.

Chia Oil Microencapsulation by Spray Drying Using Modified Soy Protein as Wall Material

“…The color of the powders darkened with increasing the amount of crosslinker initially added. The microcapsule moisture content and water activity were around 2.96 and 5.86% and 0.17, respectively, which is similar to reported in the literature (Bordon et al [8]). With regard to the oil distribution in the microcapsules, the encapsulation efficiency was between 54 and 78%.…”

“…With regard to the oil distribution in the microcapsules, the encapsulation efficiency was between 54 and 78%. Similar results were also obtained by González et al [2] for SPI and maltodextrin microcapsules with values between 52 and 65%; Bordon et al [8] for SPI and gum Arabic microcapsules with values between 68 and 87%. The relative abundance of the unsaturated fatty acids after oil microencapsulation was composed of 64.1%, 19.4% and 6.5% of linolenic, linoleic, and oleic acid, respectively.…”

Utilization of gallic acid‐crosslinked soy proteins as wall material for chia oil microencapsulation

“…Due to the dominant impact of the drying process on the obtained results and the notable deviations inherent to this method, no outstanding pattern regarding the influence of the wall material composition on EE was observed. Similar results have been reported for SPI and gum arabic microcapsules 28 and SPI and maltodextrin microcapsules. 3 The color and morphology of the microcapsules are especially important properties since they affect the appearance of food products.…”

“…1 The MC and aw results were similar to those previously reported. 3,28,29 EE was between 59% and 71% (Table 1) which were characteristic values for microcapsules obtained by spray-drying. Due to the dominant impact of the drying process on the obtained results and the notable deviations inherent to this method, no outstanding pattern regarding the influence of the wall material composition on EE was observed.…”

Complex coacervation and freeze drying using whey protein concentrate, soy protein isolate and arabic gum to improve the oxidative stability of chia oil

“…Moreover, a yellow color has been usually associated with the oxidation of triglycerides and free fatty acids 30 . Recently, Bordón et al 62 . studied the microencapsulation of CO in freeze‐dried SPI/AG complex coacervates, and reported similar WI values (37.34–38.82) to those shown in Table 3.…”