Effect of modified starches and gum arabic on the stability of carotenoids in paprika oleoresin microparticles

Abstract

The influence of gum arabic, modified starches (EMCAP® and SNOW-FLAKE® [SN]) and their combination (1:1) as wall materials in microencapsulation of paprika oleoresin (PO) by emulsification followed by spray drying and the stability of color and total carotenoids during particle storage were examined. Emulsions containing 20.5% (w/w) total solids were characterized by droplet size, droplet size distribution, and turbiscan stability index (TSI). Microparticles were evaluated with respect to physicochemical and morphology properties, and their carotenoids stability for 45 days at 25 and 35 °C. Small droplet size and TSI< 3% after 2 h of preparation for all emulsions were observed. Microparticles presented irregular surfaces with cavity formation and bimodal distribution with volume diameters ranging from 9.2 to 31.3 μm. Powders had low values of a_w and moisture, high solubility, and good encapsulation efficiency (> 90%). Color and carotenoids stability data showed the greatest protection was offered by SN as a wall material at 25 and 35 °C in relation to other wall materials and values found for free oleoresin. These results suggest the use of these microparticles as coloring agents in the foodstuff applications.

Keywords:

• Stability
• spray drying
• modified starch
• emulsion
• coloring agent

Acknowledgments

We also thank to CNPq for the doctoral scholarship (Process n° 141111/2018-6) granted to Fernanda R. Procopio, research grant for Miriam D Hubinger (CNPq (306461/2017-0)) and Scientific Initation scholarship (PIBIC) (Process 03/2018), SAE-UNICAMP for the Social Assistance and Scientific Initiation Scholarship (BAS-IC) provided to Eveling Oliveira Bezerra.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

The authors are grateful to São Paulo Research Foundation (FAPESP) for the financial support (EMU 2009/54137-1, 2007/58017-5, 2015/11984-7, and 2018/20466-8), and scholarship conceded to Ana Gabriela da S. Anthero (Process number: 2018/02132-5), and to Talita A. Comunian (Process 2018/01710-5).