Do Jalapenos Get Hotter When They Turn Red?

By Paul Smart •  Updated: 06/14/21 •  5 min read

Do Jalapenos Get Hotter When They Turn Red? If you are growing Jalapenos at home you may be wondering which color fruit is hottest, green or red? And how much of a difference is there in the level of heat between the two types of fruit?

Jalapenos do get hotter as they age and turn from green to red. Studies have shown that the Capsaicin levels, the chemical responsible for the heat, increases within the Jalapeno as the fruit develops and peaks when the color of the fruit changes. However, studies have also shown that if the Red Jalapenos are left on the plant for an extended period of time the level of Capsaicin will begin to fall again.

A 2019 article published in the Journal for the American Chemical Society tracked the development of Capsaicin levels in several hot chillies throughout the growing cycle. What the study found was that the initial concentration of the Capsaicin was relatively low in the first 3 weeks after the appearance of the fruit. However, this level rose rapidly between weeks 3 to 6, week 6 often coincided with the color change of the fruit.

After that initial peak at 6 weeks a decline was observed, however, at 10 weeks the level of Capsaicin still remained higher which indicates that red jalapenos are indeed hotter than green ones.

A similar study in 2020 looked at the changes in capsaicin level for hot peppers where the color change went from green to yellow, brown, and orange and found fairly similar results. The capsaicin levels in most cases peaked just at the point where the color change was occurring.

The images below show samples of the 4 different hot peppers ripening over a 10 week period starting 13 days after fruit first appeared.

The capsaicin level of each fruit at each stage is provided in the graph below. In three out of the four cases, the levels peaked at 27 or 34 days just as the color change was occurring.

Can You Pick Jalapenos When They Are Still Green?

Given, that heat varies depending upon the age of the Jalapenos and hot peppers, the obvious question is can you harvest the fruit when it is still green?

Jalapenos and hot peppers can be harvested at any stage for use in cooking which includes when they are still green. Commercially available pickled Jalapenos which are frequently used in Mexican cooking, are almost always green.

Pickling Jalapenos is one of the best ways to store your harvest for the long term. I had a big harvest 3 or 4 years ago that I am still eating now. To produce pickled Jalapenos that taste the same as the ones that you can buy is extremely quick and easy to do. Below is the recipe that I use to make them.

How To Make Pickled Jalapenos




How To Control The Heat Of Hot Peppers?

As mentioned earlier in the article the timing of the harvest significantly affects the degree of heat you can get from a chilli. However, the heat of hot peppers can be controlled by the way that the pepper is prepared prior to heating/cooking.

The capsaicin levels within the hot peppers are not evenly distributed throughout the fruit, it is concentrated in the placenta of the fruit. The placenta is the central part of the fruit in which the seeds reside, it is normally paler in color than the rest of the fruit.

The capsaicin levels within this section of the fruit are between 10 and 30 times higher than other sections of the fruit and there are some cases where capsaicin resides only in this section of the pepper. To read more about this click here.

To reduce the heat of the pepper a portion or all of the placenta can be removed, depending upon your personal taste. However, it is important to note that the degree of heat will vary substantially depending upon the particular variety of pepper grown. To learn more about the huge variety of peppers that exist click here.

Paul Smart