Microencapsulation of blackberry pulp with arrowroot starch and gum arabic mixture by spray drying

Abstract

This research work aimed to obtain blackberry pulp powder by spray drying and, by an experimental design, evaluated the effect of inlet air temperature (100–150 °C) and blackberry pulp solids:arrowroot starch/gum arabic solids ratio of 1:0.5–1:2 on the physicochemical properties of the powders. Arrowroot starch and gum arabic present glass transition temperature (Tg) values above 100 °C; hence it was possible to employ them as carriers in blackberry pulp spray drying in order to increase Tg of the system. Powder yield and solubility increased with increasing blackberry pulp solids:arrowroot starch/gum arabic solids ratio of 1:0.5–1:2, whereas hygroscopicity decreased. Yield, solubility and hygroscopicity of the powders increased and water activity decreased, with increasing inlet air temperature. The powders presented low moisture content and water activity. Temperature of 143 °C and blackberry pulp solids:arrowroot starch/gum arabic solids ratio of 1:1.78 were the optimal conditions to obtain high yield and blackberry powders that are soluble in water and less hygroscopic.

KEYWORDS:

• Glass transition temperature
• process yield
• moisture content
• average size
• hygroscopicity
• solubility

Acknowledgements

The authors thank Espaço da Escrita – Pró-Reitoria de Pesquisa - UNICAMP - for the language services provided.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

The authors are grateful to the Coordination for the Improvement of Higher Education Personnel (CAPES, No 01-P-3712/2017) and to the School of Agricultural Engineering – University of Campinas for their financial support.