CaCO3 loaded lipid microspheres prepared by the solid-in-oil-in-water emulsions technique with propylene glycol alginate and xanthan gum

Abstract

Calcium carbonate (CaCO3) is difficult to deliver in food matrices due to its poor solubility. In this work, CaCO3 powders were encapsulated into Solid-in-Oil-in-Water (S/O/W) emulsions to fabricate delivery systems. The impact of the concentrations of propylene glycol alginate and Xanthan gum (PGA-XG) complexes on the physical stability and structural characteristics of S/O/W calcium-lipid emulsions microspheres were studied. The S/O/W calcium-lipid emulsions were characterized by the particle size, zeta potential, physical stability, and apparent viscosity. The S/O/W calcium-lipid emulsion has higher physical stability (including 6-week storage at 4°C), smaller mean particle size (7.60 ± 1.10 μm), and higher negative zeta-potential (45.91 ± 0.97 mV) when the concentration of PGA-XG complexes was 0.8 wt%. Moreover, Confocal laser scanning microscopy (CLSM) images confirmed that the CaCO3 powders were encapsulated in the O phase. Transmission electron microscopy (TEM) showed that S/O/W calcium-lipid emulsion was spherical. The X-ray diffraction (XRD) analysis further confirmed that CaCO3 was loaded in the S/O/W calcium-lipid emulsion as an amorphous state. The formation mechanism of S/O/W calcium-lipid microspheres was studied by Fourier transform infrared spectroscopy (FTIR) and Raman spectrum analysis. This study provided new ideas that accelerate the creation of a novel type of calcium preparation with higher quality utilization.

Structural changes and calcium bioaccessibility of calcium fortified milk containing CaCO3 loaded solid‐in‐oil‐in‐water emulsion during simulated in vitro digestion

“…When the XG concentration was 4 g L −1 , the change in light transmittance of the CaCO 3 loaded S/O/W emulsion decreased significantly, and the CaCO 3 loaded S/O/W emulsion maintained good physical stability. This is similar to our previous experimental results 11 …”

“…To ensure adequate dissolution, the above W phase solution was stirred magnetically at 50 °C for 2 h and then stored at 4 °C overnight. CaCO 3 loaded S/O/W emulsions were prepared according to the method described by Li et al 11 . with a slight modification.…”

“…To ensure adequate dissolution, the above W phase solution was stirred magnetically at 50 °C for 2 h and then stored at 4 °C overnight. CaCO 3 loaded S/O/W emulsions were prepared according to the method described by Li et al 11 with a slight modification. Briefly, the S/O phase was prepared by dispersing CaCO 3 in MCT oil (100 g kg −1 ) using a mixer (ULTRA TURRAX T25 digital; IKA, Staufen, Germany) at 10 000 rpm for 1 min and then magnetic stirring for 1 h at 25 °C.…”

“…For instance, oil‐in‐water (O/W) emulsions were used to deliver lutein to improve its retention ratio and bioaccessibility after simulated digestion 8 . The solid‐in‐oil‐in‐water (S/O/W) emulsion is a new method for encapsulating solid‐phase nutrients into liquid foods, which can effectively improve the dispersion stability of solid‐phase nutrients and thus ensure good properties of liquid foods 9‐12 . It is therefore necessary to carefully design the delivery vehicle to achieve better digestion and absorption based on the physicochemical properties of functional factors and the real application scenarios in the actual system 13,14 …”

“…8 The solid-in-oil-in-water (S/O/W) emulsion is a new method for encapsulating solid-phase nutrients into liquid foods, which can effectively improve the dispersion stability of solid-phase nutrients and thus ensure good properties of liquid foods. [9][10][11][12] It is therefore necessary to carefully design the delivery vehicle to achieve better digestion and absorption based on the physicochemical properties of functional factors and the real application scenarios in the actual system. 13,14 In this study, we first developed a CaCO 3 loaded S/O/W emulsion based on S/O/W techniques using dairy-derived protein [whey protein isolate (WPI)], anionic polysaccharide (XG), high-quality oil [medium chain triglyceride (MCT)], and CaCO 3 .…”