Abstract

Background: There are a great interest for studying the health benefits of vegetables that are rich sources of bioactive compounds. Dried chili is a spice product and the one most widely used as condiments in the world. The quality of dried chili is assessed by a number of different parameters such as color, ascorbic acid content and volatile flavor compounds.

Methods: Two varieties of red chili pepper “Serrano and Fresno” was used in this study to investigate the effect of two different drying methods “solar drying at 45 °C and conventional drying at 60 °C” on the physical properties "color, rehydration ratio and firmness" and bioactive content “total phenolic compound, vitamin C and Total carotenoids” of chili pepper.

Results: The solar drying method recorded lowest decreasing in color parameters “L, a, and b”. Moreover, rehydration ratio of solar dried chili pepper is higher than conventional drying method, and firmness of conventional dried chili pepper received the lowest texture intensity score. The conventional drying method had the highest content of all bioactive compounds such as phenolic compounds (321.12-207.14 mg/100 g), vitamin C (37.34-29.00 mg/100 g) and Total carotenoids (92.34- 90.75 mg/100 g) for Serrano and Fresno varieties respectively.

Conclusion: The solar drying method showed high values for physical properties “color and rehydration ratio” than the conventional drying method for both varieties, and there was a significant reduction in the bioactive content of all the dried chili varieties. But the reduction was significantly lower in the conventional dryer than the solar dryer.

Keywords: Red chili pepper, phenolic compounds, drying, vitamin C, physical properties.

Graphical Abstract