Investigating the effects of spray drying conditions on the microencapsulation efficiency of pumpkin seed oil

Microencapsulation of Hibiscus sabdariffa L. extract using porous starch and gum Arabic: Optimized process, characterization, stability, and simulated gastrointestinal conditions

Hibiscus extract exhibits considerable antioxidant activity and a high anthocyanin content, which suggesting potential health benefits. However, these compounds are highly susceptible to environmental factors. The aim of this study was to establish the optimal conditions for the encapsulation of Hibiscus sabdariffa extract (HSE) using mixed porous maize starch-gum Arabic to enhance the stability of bioactive compounds under accelerated aging conditions. Response surface methodology (RSM) was used to optimize microencapsulation conditions through spray drying. The optimal conditions for microencapsulation of HSE by RSM were determined to be 126 °C at the inlet temperature (IT) and 8.5 % at the total solid content (TSC). Using these conditions, the amount of bioactive compounds in optimized microcapsules (OMs) was 2368 mg GAE/100 g, 694 mg QE/100 g, and 930 mg EC3G/100 g, of phenolic compounds, flavonoids, and anthocyanin, respectively. The release rate of anthocyanins during in vitro digestion was more effectively regulated in the OM sample, which retained up to 40 % of anthocyanins compared with 10 % in the HSE. The experimental values in this study exhibit high assertiveness, which renders the optimization model technologically and financially viable for the encapsulation of bioactive compounds with potential use in the food and pharmaceutical industries.

Microencapsulation of total saponins from stem and leaf of Panax notoginseng by freeze and spray drying: Process optimization, physicochemical properties, structure, antioxidant activity, and stability

Ginsenosides are the primary active substance in ginseng plants and have a variety of benefits. However, its light and heat stability are weak and easy to decompose. This study used gum arabic (GA) and maltodextrin (MD) as wall materials, and 1% Tween 80 was used as emulsifier. Response surface methodology was used to optimize the preparation process of total saponins in the stems-leaves of Panax notoginseng (SLPNs) (SSLP) microcapsules by spray drying and freeze drying techniques. Under optimal process conditions, the two microcapsules have better solubility and lower moisture content (MC). The color of spray-dried SSLP microcapsules was greener and bluer, and the color was brighter. In morphology, the spray-dried SSLP microcapsules were spherical with a slightly shrunk surface, whereas the freeze-dried ones were lamellar and porous. The two microcapsules have strong stability under different storage conditions and in vitro gastrointestinal digestion simulation. In addition, both microcapsules and free SSLP contained multiple ginsenosides. At the same time, both microcapsules had good free radical scavenging ability. These results indicate that the microencapsulation technology could improve the stability and bioavailability of SSLP, which is expected to provide a reference for the intensive processing of the SLPN. PRACTICAL APPLICATION: After microencapsulation, the stem and leaf extract of Panax notoginseng improved its stability and taste, which laid a foundation for making more nutritious and better tasting food of the stem and leaf of P. notoginseng.

Spray dried date fruit extract with a maltodextrin/gum arabic binary blend carrier agent system: Process optimization and product quality

Bioactive compounds can be protected from degradation through encapsulation, increasing their bioavailability and shelf life. Spray drying is an advanced encapsulation technique mainly used for the processing of food-based bioactives. In this study, Box-Behnken design (BBD)-based response surface methodology (RSM) was used to study the effects of combined polysaccharide carrier agents and other spray drying parameters on encapsulating date fruit sugars obtained from a supercritical assisted aqueous extraction. The spray drying parameters were set at various levels: Air inlet temperature (150-170 °C), feed flow rate (3-5 mL/min), and carrier agent concentration (30-50 %). Under the optimized conditions (inlet temperature of 170 °C, the feed flow rate of 3 mL/min, and carrier agent concentration of 44 %), a maximum sugar powder yield of 38.62 % with 3.5 % moisture, 18.2 % hygroscopicity and 91.3 % solubility was obtained. The tapped density and particle density of the dried date sugar were estimated as 0.575 g cm-3 and 1.81 g cm-3, respectively, showing its potential for easy storage. In addition, scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis revealed better microstructural stability of the fruit sugar product, which is essential for commercial applications. Thus, the hybrid carrier agent system (maltodextrin and gum arabic) can be considered a potential carrier agent for producing stable date sugar powder with longer shelf-life and desirable characteristics in the food industry.