Influence of encapsulation techniques on the structure, physical properties, and thermal stability of fish oil microcapsules by spray drying

Abstract

The physical properties and thermal stability of gelatin/gum‐Arabic microcapsules loaded fish oil, developed by various encapsulation techniques such as directly spray‐dried microcapsule, complex coacervation microcapsule, and double‐encapsulated microcapsule (DEM) were investigated. All the particles dried by spray drying and evaluated by scanning electron microscopy (SEM), thermal analysis, cumulative release analysis, and rheological measurements. The external and internal core–shell structure of microcapsules observed by SEM, were beneficial to improving the thermal stability of particles. The DEM possessed stable two‐shell structure, and retained 25.39% weight after thermogravimetric analysis, 93.71% encapsulation efficiency only released 11.8% core material in 100 °C water bath over 30 min, which could perform more stable during processing, transportation, and consumption. Above all, these results could be the basis of selecting suitable encapsulation technique, processing temperature, and time control in practical production when functional microcapsules needed. Practical applications This article is aimed at characterize structures, relative physical properties and thermal stability of three types of microcapsules: directly spray‐dried microcapsules, complex coacervation microcapsules, and double‐encapsulated microcapsules, for encapsulating fish oil during processing and storage. Therefore, all the results such as encapsulation efficiency, loading capacity, surface oil, particle size, thermal stability, and fish oil cumulative release percentage of microcapsules at certain temperature could be used as guidance on practical functional foods production like selecting a suitable encapsulation approach, processing temperature, or time control.

Curcumin and fisetin internalization into Saccharomyces cerevisiae cells via osmoporation: impact of multiple osmotic treatments on the process efficiency

“…Microencapsulation of plant‐derived bioactive compounds has attracted industrial and scientific community interest as valuable alternatives to protect phytochemicals against deleterious processing and environmental conditions, facilitating their technological incorporation into food and pharmaceutical preparations (Yu et al . ; Belščak‐Cvitanović et al . ).…”

New Trends in the Microencapsulation of Functional Fatty Acid‐Rich Oils Using Transglutaminase Catalyzed Crosslinking

“…A schematic image from the internal structure diagram of edible oil‐loaded microcapsules prepared with (A) emulsion‐based spray drying, (B) complex coacervation and (C) DE‐EG methods (Adapted from Yu and others ).…”

“…In addition, the emulsion instability because of the creation of intermittent oil deposits during freeze drying can considerably reduce the EE (Anwar and Kunz ). Yu and others () have currently investigated the impact of various encapsulation techniques on the EE of fish oil microcapsules. They concluded that microcapsules produced by DE‐EG method had higher EE level (93.71%) as a result of the second embedding, than those prepared by complex coacervation (89.78%) and emulsion‐based spray drying (86.9%) techniques.…”

“…Presence of TGase crosslinking in the coating wall could significantly enhance the thermal stability of coacervate capsules containing functional lipophilic ingredients such as capsanthin (Huang and others ), jasmine oil (Lv and others ), styralyl acetate (Xiao and others ), chia seed oil (Timilsena and others ), and fish oil (Yu and others ). Developing the enzymatic crosslinks with the increase of denaturation temperature can promote high thermal resistance of microcapsules containing thermally sensitive ingredients due to the hindrance of moisture evaporation from the surface (Soper and Thomas ; Huang and others ).…”

“…Developing the enzymatic crosslinks with the increase of denaturation temperature can promote high thermal resistance of microcapsules containing thermally sensitive ingredients due to the hindrance of moisture evaporation from the surface (Soper and Thomas ; Huang and others ). Yu and others () showed that the fish oil‐loaded multicore microcapsules in DE‐EG method due to the delay in evaporation of structural water had better thermal stability in the temperature range of 80 to 150 °C when compared to those that were prepared with emulsion‐based spray drying and complex coacervation techniques. However, the wall compactness/integrity of TGase‐crosslinked microcapsules developed by complex coacervation against higher temperatures (250 to 350 °C) was much higher than that of microcapsules prepared by the two other techniques due to toughened film layer and single‐core structure.…”