Complex coacervation of acid-extracted fiber from butternut squash (Cucurbita moschata) and protein

Investigating the effect of wall material and pressure homogenisation on encapsulation parameters and thermal stability in chia seed oil microcapsules

AIM

To evaluate the effect of different wall material (WM) matrices followed by homogenisation to encapsulate chia seed oil (CSO) using freeze drying technology.

METHODS

CSO was encapsulated using three ratios (100/0, 50/50, and 100/0) of two WM matrices: MTS/WPC (modified tapioca starch-whey protein concentrate) and MD/WPC (maltodextrin-whey protein concentrate). The evaluation included encapsulation efficiency (EE), oxidative stability, and α-linolenic acid (ALA) retention. Homogenised microcapsules (-H) were then assessed for storage and thermal stability, along with cumulative oil release.

RESULTS

The MD-WPC-H 50/50 microcapsules had superior EE (97.32%), higher ALA retention (60.2%), storage stability (up to 30 days), higher thermal stability (up to 700 °C), and desirable oil release in simulated condition.

CONCLUSION

Selecting suitable WM and homogenisation is key for improving EE, storage, thermal stability, and targeted release. The CSO microcapsule can serve as a functional ingredient to improve the quality of diverse food products.

Novel complex coacervates based on Zedo gum, cress seed gum and gelatin for loading of natural anthocyanins

This study aimed to characterize novel complex coacervates based on Zedo gum and cress seed gum as natural polysaccharides with gelatin (type-A and type-B) as potential wall materials for encapsulation of anthocyanins. The coacervates were prepared under optimum conditions (pH and gum to gelatin ratio), freeze-dried, and the resulted powders were analyzed in terms of thermal stability, morphology, and molecular interactions. The thermogravimetric analysis revealed that molecular interaction between polysaccharides and gelatins led to enhance the thermal stability of gums. The morphology of coacervates showed that while ZG-gelatin and CSG-gelatin coacervates resulted in cubic and irregular particles, freeze-drying severely changed the morphology of coacervates. Moreover, SEM images at lower magnification showed big voids for lyophilized coacervates, while SEM images confirmed a compact and dense microstructure of coacervates at higher magnification and BET method. Also, the molecular interaction of polysaccharides and gelatin in aqueous media was assessed using Raman spectroscopy. Furthermore, findings showed that the type-A of gelatin is a more suitable protein to form coacervates with polysaccharides. In the next step, natural anthocyanins from barberry were encapsulated by proposed coacervates as wall material. The encapsulated extract had elevated thermal stability and showed a lower degradation rate.