Capsaicin content in red habanero chilli (Capsicum chinense Jacq.) and its preservation after drying process

The present work has determined and evaluated the influence of the drying process on the preservation of capsaicin, polyphenols and the antioxidant activity of whole red habanero chilli, as well as pericarp, placenta and seeds. For the drying process, drying kinetics have been carried out at different temperatures (40, 50, 60 and 70 °C) and drying speed (2 and 4 m/s), monitoring the relative humidity. The extracts were carried out with a mixture of solvents methanol-ethanol-water (6: 2: 2; v/v). The obtained extracts were analysed in terms of capsaicin and total polyphenol content, along with antioxidant capacity using ABTS and DPPH methods. A response surface model was used to obtain the temperature and drying speed conditions to maximize the preservation percentage of the bioactive compounds. It was determined that the highest percentage of capsaicin conservation occurred in the dried pericarp at 70 °C and 4 m/s. Likewise, it was observed that it is possible to preserve 100% of the total phenols in the pericarp when dried at 50, 60 and 70 °C and 2 m/s, as well as in the placenta dried at all handled temperatures and both speeds, while in the seeds dried at 60 °C and 2 m/s. The best results for the preservation (ca. 100%) of antioxidant activity were obtained by the ABTS method when the placenta was dried at 50 and 60 °C at 2 m/s, and seeds at 50 °C and 2 m/s. These results were confirmed through the response surface design; while the seeds showed that drying at 54 °C and 2 m/s allow maximizing the preservation of total phenols, and the greater antioxidant activity via ABTS can be achieved at 48 °C and 2 m/s.