Capsaicinoids and Peroxidases - Summary of Critique 2

Capsaicinoids are compounds responsible for hot flavors in chile peppers. There are currently seven known capsaicinoids but two of them, capsaicin and dihydrocapsaicin, are responsible for nearly all the hot flavor in chile peppers. Numerous studies have been performed on chile peppers and their respective capsaicinoid content. Such studies have revealed a directly proportional relationship between capsaicinoid mass and perceived hot flavor. Simply put, different chile peppers differ in pungency based on capsaicinoid levels. Recent studies have been aimed not at changes in capsaicinoid content between peppers but changes in capsaicinoid content with time. One such study is Changes in Capsaicinoids during Development, Maturation, and Senescence of Chile Peppers and Relation with Peroxidase Activity.

The objective of the research paper is to investigate the changes of capsaicinoid content of three chile peppers (Habañero, De árbol, and Piquin) with time. Changes in capsaicinoid levels are caused by compounds called peroxidases. Peroxidases are compounds located in the outermost epidermal cell layer in chile peppers and are responsible for oxidizing and degrading capsaicinoids. The purpose of the article is to investigate the relationship between peroxidase activity and capsaicin, dihydrocapsaicin, and total capsaicinoid levels in the Habañero, De árbol, and Piquin.

The experiment reported that capsaicinoid (including capsaicin and dihydrocapsaicin) levels were inversely proportional to peroxidase activity. In both the field-grown and greenhouse-grown Habañero, capsaicinoids levels continued to rise until 45-50 days after flower maturation and then dropped as peroxidase activity increased. De árbol followed the same trend as the Habañero, except capsaicinoid levels peaked at 40 days following flower maturation. Piquin did not follow the trend of the previous two. Peroxidase activity in the Piquin began to increase before any decrease in capsaicinoid levels. The highest level of capsaicinoids were found in greenhouse-grown Habañero followed by field-grown Habañero, De árbol, and then Piquin. The highest peroxidase activity was witnessed in De árbol, followed by Piquin, field-grown Habañero, and greenhouse-grown Habañero.

The inverse relationship between capsaicinoid content and peroxidase activity suggests that peroxidases are responsible for capsaicinoid degradation. Because both peroxidases and capsaicinoids are both located in the cell walls of chili peppers, there is most likely a competition between the two. During the early stages of development, capsaicinoids are continually produced and overcome the activity of peroxidase. As time goes on, peroxidases build up and eventually overcome and degrade the capsaicinoids. As a result, the ideal harvest time on the basis of maximum pungency (greatest capsaicinoid content) is between 40 – 50 days following flower maturation for all three chile peppers.