# A Preliminary Study of Swell-Drying as an Innovative Process for Improving the Nutritional Quality of Dried Lucuma (Pouteria lucuma) and Dried Goldenberry (Physalis peruviana L.)

## TL;DR

This study explores a new drying method called swell-drying to improve the nutritional and antioxidant qualities of dried lucuma and goldenberry fruits.

## Contribution

The study introduces a novel swell-drying process combining different drying techniques to enhance the nutritional and antioxidant properties of two fruits.

## Key findings

- Swell-drying preserved and enhanced the nutritional quality of both lucuma and goldenberry.
- Optimal DIC treatments increased antioxidant activity in both fruits significantly compared to controls.
- Lucuma and goldenberry showed distinct optimal conditions for maximizing antioxidant properties.

## Abstract

Lucuma and goldenberry are rich in bioactive compounds, and swell-drying (SD) can help preserve these properties. This study examined how SD impacts the nutritional quality of lucuma and goldenberry. The SD process involved the following: (1) initial pre-drying, with Interval Highly Active Drying (IHAD) for lucuma and Continuous Convective Airflow Drying (CCAD) for goldenberry, (2) a DIC treatment under an experimental design with 13 treatments, and (3) a final CCAD step. The parameters studied for DIC were steam pressure (0.1 to 0.5 MPa) and treatment time (5 to 55 s). Bromatological analysis and antioxidant activity were the response variables. Under accurate SD conditions, both fruits maintained their nutritional quality and increased their antioxidant activity compared to controls. Carbohydrates, proteins, lipids, fiber, and ash average contents of lucuma were 88.73%, 7.28%, 1.18%, 1.88%, and 0.92%, respectively. The DIC treatment of 0.27 MPa for 22 s increased the percentage of ABTS and the DPPH inhibition of lucuma by 1.2 and 1.5 times, respectively. For goldenberry, carbohydrates, proteins, lipids, fiber, and ash average contents were 71.87%, 7.18% 7.01%, 6.60%, and 6.77%, respectively. DIC treatment of goldenberry at 0.5 MPa for 30 s increased ABTS % inhibition by 1.5 times, and DIC at 0.10 MPa for 30 s increased DPPH inhibition by 4.9%.