Thanks for the tip! I wish it were easier to find red jalapenos - I love them.

I grow jalapenos and have noticed that even after I've picked them while they are still green, if I don't use them up right away, they will turn red in the kitchen counter bowl where I've placed them. Sort of the way that a green tomato might continue to ripen after it's picked. Doesn't happen all the time, sometimes they just wither instead of continuing to ripen. ~Elise

Ah-ha! Thanks for the insight.

Thank you for the tip, it will help a lot.

This is how my Husband's cousin taught me how to tell the difference of Hotness in the Jalepeno's. Very good visual example too.

I grow jalapenos on my balcony garden - should I leave them on the plant longer to make them hotter? Or is it only a post-picking transformation as you mentioned in an earlier comment? First time gardener!

If you don't pick them, they will eventually turn red. ~Elise

Thank you! I actually remember thinking at the vegetable market, "why are they selling these jalepenos; they look old". Now I know why!

Good to know. Seems like common sense, but I'd never really thought about it before. Thanks for the tip!

This is great for me, because I finally acknowledged that I really and truly loathe bell peppers in all colors, but I love a bit of spice to some of my meals. This way I can use jalapeños without fear!

You should still fear jalapeños (wash hands carefully after cutting them, or wear gloves), and should always taste before using, so you know how much heat you are adding to a dish. ~Elise

Thanks Elise. I love having the validation that it takes stretch marks to make a red-hot mama!

HAH HAH HAH ~Elise

What a great tip! I was working with some jalapeños last night and they were so hot I got a chemical burn on my hands. I couldn't figure out why they were so much hotter than usual!

Good info on the jalapenos. Our local New Mexico chile is grown only for its individual hotness. It does not change its heat as it changes color from green to red.

Thanks Elise! I grow jalapenos too and waited to pick so they would be bigger for stuffing and then couldn't eat them due to be so overly hot.(They did have lots of stretch marks) Do you know if soil or growing temperatures makes a difference too? I'm in the midwest and we're having a much cooler summer than normal.

No idea on the soil or temperature. I suspect it has more to do with the variety, but who knows? Sometimes my peppers are all pretty hot, sometimes less so. Right now I'm growing some Anaheims that are completely mild. No heat whatsoever, but they taste great. I'll buy what I think is the same variety starter from the same nursery and have different results based on the season. My tomatoes same thing. This year they aren't nearly as flavorful as in past years. We had an exceptionally cool start to the summer and the local paper reported that the tomato crop was trailing by 4-6 weeks because of it. Tomatoes and peppers are related, so if heat affects tomatoes, maybe it affects chiles too? ~Elise

First of all, I'm so glad to see someone spell "jalapeños" correctly!!

Secondly, thanks for the tutorial about chiles. Your photos are lovely.

Thanks for the tip, I didn't know about the white stripes, I just thought they were scratches! I was under the impression, based on green to red bell peppers, that the change to red makes them somewhat sweeter. Not necessarily less hot, but with more consentrated sugars in the maturing pepper it gets a lightly sweetened heat (not really sweet as we think of sweet). Like you advise, I always taste the peppers I chop to add to a dish, just to note how much heat is in the individual pepper. They do vary.

I just read recently (maybe Gourmet magazine?) that it's a myth that there's any heat in the seeds, it's all in the "ribs".

Yeah, just think about that myth the next time you eat a seed. Hah! ~Elise

Great post - I love to cook with fresh peppers, but when I first started out the results were unpredictable. One time I'd make a dish with 2 jalepenos and it would turn out great. Other times, it would be turn out so mild it would have no heat at all or almost be inedible!

I started guaging the heat of the peppers by smell. You can cut it in half and get a good idea of the heat of that pepper and adjust the amount you put in accordingly.

I had never heard your suggestion about the striations, but it makes sense!

Thank you for charing this information, I didn´t know how to choose Jalapeños.
Regards
Moira

Even with this tip, peppers are quite variable. Always taste before using. Last week, I bought two poblanos and one was very mild while the other was fairly hot. I know because I tasted them.

A bit more info from Jean Andrews' lovely book "Peppers" -- the ribs have about double the concentration of capsaicin as the outer wall and bleach or milk will remove capsaicin from your hands. It is also soluable in alcohol.

Personally, I always use serranos instead of jalepenos. They just taste better.

Thanks for the enjoyable tip and great photos. I've noticed that some of my local markets (not the Latin tiendas, but stores like Safeway) carry a different brand of chili that they call "red jalapeños" except that they don't appear to be jalapeños at all unless there is a variety that I'm unaware of. Do you happen to know if this is a misnomer or if it is a different variety with the same common name? The principle difference is at the stem, which isn't as round as on "green" jalapeños. They aren't just the usual sort of jalapeños that have turned red on the shelf.

Haven't heard of it. ~Elise

Thanks for the great tip on jalapenos. I make a
Mango & Jalapeno Jelly, my one canning claim to fame.

I love our recipe for jalapeno jelly which uses cranberries for color and pectin. I love the mango jalapeno combination and think it would be terrific in a jam/jelly. ~Elise

What great information! I really do like the red ones the best; somehow the sweetness of them does not make them seem as hot to me as the green.

I've had the same problem with jalepenos, that's why I just steer clear of them altogether and user Serrano chiles which tend to be more predictably spicy. We have these chilies at Indian groceries here in NY that tip the scale at 1M scoville units (about 200x more capsaicin than Jalepenos)

This is not completely accurate. The striations do imply a hotter pepper, but if you allow the pepper to ripen to the point where it's red it will lose some heat and get sweeter (though it will likely still be hotter than before the striations).

If you're growing peppers the striations are a good indication of when to harvest, though not all pepper varieties have them.

I heard somewhere that you can tell the hotness of a chili by how curved the stem is. The more curve, the more heat. It's been pretty true for me - but it could also be because the more mature peppers have more curved stems.

I buy serranos because they seem consistently hotter than jalapenos. And they're the same price at grocery stores. Also jalapenos taste "green" to me, like how green bell peppers taste in comparison to red or orange ones. Serranos don't have that "green" taste.

Many years ago we found out that there is a great way to control the heat of your peppers if you are growing your own.

For mild peppers: water regularly, neve let them get too dry. Happy peppers seem to grow up much to be much milder in heat.

For HOT peppers: abuse your pepper plants. Wait until they are wilted to water them, don't let them die (no way to bring them bck from the grave), but abuse the plants. It just seems to make the peppers mean.

Also, for all varieties of peppers (including bell peppers) they are really ripe when they are red. Peppers picked green are immature.

Enjoy.

The soil in which the chile is grown is pre-eminent. If you want really hot chiles then grow them hydroponically. That in itself will increase the capsacin by about 10 fold in what ever chile you decide to grow.

This is great- I can't wait to try this out!! I've secretly wondered for a while what the secret to this was!

From a paper on Padrón Chili peppers: Capsaicinoids were detected 14 days after flowering in the first stage. Their levels remained low for 21 days, but 28 days after flowering capsaicinoids increased moderately, and finally, at the end of development, the cv. Padrón pepper exhibited a dramatic increase in capsaicinoid levels with the highest values found in the fifth stage, 42 days after flowering. The level of capsacinoids in the cultivar Padrón was lower than that in other fruit varieties (Iwai et al., 1979; Salgado-Garciglia & Ochoa-Alejo, 1990). -Estrada et al. 2000, J. Agric Food Chem.

It's not Jalapeño, but the fact that 4 other cultivars had similar capsaicinoid production patterns suggests that they do get hotter towards maturation.

The striations that you photographed are actually cracks in the skin of the fruit that develop when there is excess root pressure to where the skin cannot push back. Usually fruit (of any kind) are more susceptible to this sort of cracking when they are more mature (Tomatoes, melons, etc...). As the fruit expands and matures, the skin is stretched thinner and thinner and the fruit wall begins to soften and together cannot push back against the pressure from the roots. Tiny fractures occur in the skin to relieve the pressure which then become suberized and more visible.

If anything, the fractures indicate maturity, which does appear to correlate with increased capsaicinoid content.

Also, as many people mentioned, there is strong evidence in the literature that increased stress on the plant will induced increased production of capsaicinoids. Letting them wilt, flooding the roots, handling the plants, increased soil temperatures, and increased air temperatures will all stress out the plant more and cause increased production.

Your method may not be perfect Elise, but there is scientific precedence to back of some of your ideas.

Elise, this is a wonderful tip. And, based on Brandon's research, it looks like this would apply to poblano peppers as well. Thanks Brandon for doing that research!

Thanks for this, I used to wonder about the striations. This summer we have our own peppers, chili and jalapeno plants in the garden and I have a (I guess stupid) question. On one plant we have red and green ones, some are just green, will they all turn red after green? We never tried it before because we thought that you can't grow them in Germany because our summers aren't long and hot. It does work though and we're really proud.

Yes, they will all turn red if you leave them on the plant long enough. ~Elise

Thanks for the tips, very handy! It's frustrating when chosen peppers are not as hot as you'd imagine it to be.

Like Alexis, I too wondered why my grocer always sells wrinkled old looking chiles (I use serranos rather than jalapenos, which are hotter to begin with). Very interesting... I usually get some pretty hot serranos, and I always pick the prettiest smoothest ones... I guess I still won't be going for the wrinkled ones! Cool tip though;o)