Effect of Inlet Air Temperature and Quinoa Starch/Gum Arabic Ratio on Nanoencapsulation of Bioactive Compounds from Andean Potato Cultivars by Spray-Drying

Abstract

Nanoencapsulation of native potato bioactive compounds by spray-drying improves their stability and bioavailability. The joint effect of the inlet temperature and the ratio of the encapsulant (quinoa starch/gum arabic) on the properties of the nanocapsules is unknown. The purpose of this study was to determine the best conditions for the nanoencapsulation of these compounds. The effects of two inlet temperatures (96 and 116 °C) and two ratios of the encapsulant (15 and 25% w/v) were evaluated using a factorial design during the spray-drying of native potato phenolic extracts. During the study, measurements of phenolic compounds, flavonoids, anthocyanins, antioxidant capacity, and various physical and structural properties were carried out. Higher inlet temperatures increased bioactive compounds and antioxidant capacity. However, a higher concentration of the encapsulant caused the dilution of polyphenols and anthocyanins. Instrumental analyses confirmed the effective encapsulation of the nuclei in the wall materials. Both factors, inlet temperature, and the encapsulant ratio, reduced the nanocapsules’ humidity and water activity. Finally, the ideal conditions for the nanoencapsulation of native potato bioactive compounds were determined to be an inlet temperature of 116 °C and an encapsulant ratio of 15% w/v. The nanocapsules obtained show potential for application in the food industry.

Preliminary Assessment of Tara Gum as a Wall Material: Physicochemical, Structural, Thermal, and Rheological Analyses of Different Drying Methods

“…A higher Tg can facilitate elevated temperatures during encapsulation processes, which is crucial for developing specific applications [ 22 , 30 , 47 ]. Similar glass transition temperatures have been reported for various polymeric wall materials used in spray-drying processes, as was the case for maltodextrin (155.34 °C) [ 72 ]; also, Kurozawa and Deschamps reported a Tg of 160 °C for maltodextrin [ 73 , 74 ], arabic gum (139.81 °C), native potato starch (138.26 °C) [ 22 ], quinoa starch (139.21 °C) [ 75 ], and spray-dried tara gum (157.7 °C) [ 22 ]. Glass transition temperatures below these values in the microcapsules and nanocapsules would indicate that encapsulation was successfully achieved [ 33 , 72 ].…”

“…In addition, an absence of change in heat capacity between the initial and final state was observed, which was a limitation for determining the glass transition temperature in the present study. Therefore, further analysis is required for a complete understanding of the thermal processes present in these gums, as it is known that the glass transition temperatures of natural gums are usually high [ 22 , 30 , 47 , 75 ].…”

Effect of Germination on the Physicochemical Properties, Functional Groups, Content of Bioactive Compounds, and Antioxidant Capacity of Different Varieties of Quinoa (Chenopodium quinoa Willd.) Grown in the High Andean Zone of Peru

“…The samples were read at 755 nm on a spectrophotometer (Genesys 150, Thermo Fisher Scientific, Waltham, MA, USA). Gallic acid (GA) was used as a reference standard, and the results were expressed as mg equivalent of gallic acid/100 g of sample [38,39].…”

“…The sample extracts were mixed with the diluted DPPH solution, and the samples were read at 515 nm in a spectrophotometer. Trolox was used as a reference standard, and the results were expressed as mg Trolox equivalents/g sample [30,39,41,42].…”