Blanching jalapeno peppers is necessary prior to freezing, canning or preserving. It is also economical, as freezing jalapenos allows you to purchase the peppers in-season when prices are at their lowest and use them during the winter months, when the quality of peppers dips and the price of imported vegetables and fruits increases. Blanching jalapenos prior to cooking removes a large portion of capsicum — the chemical that makes food spicy-hot — and softens their harshness, unmasking the true flavor of the pepper.
Things You'll Need
Rinse the jalapeno peppers in cold water, cut away the stem portion and slice them in half. Cut away the white pith and de-seed the peppers with a spoon. Wear food-handler gloves to avoid contact burns.
Fill a stockpot half-full with water and bring to boil. Fill a large food-storage container half with ice and half with water.
Place 10 jalapeno pepper halves in the water, allow it to return to a boil and blanch for three minutes. Transfer the jalapenos to the ice bath using a slotted spoon, allow them to chill for three minutes and place them to dry on a wire rack atop a sheet pan.
Blanch the remaining amount of peppers in batches, allowing the water to return to a boil before adding more. If freezing, place the peppers in freezer bags, mark them with the date and contents and store for up to nine months.
References and Resources"The Professional Chef 8th Edition"; The Culinary Institute of America; 2006
I Food: How to Blanch Peppers -- Pepping Up Your Recipes
Pick Your Own: How to Freeze Peppers: Sweet, Bell, Banana, Hot, Chili, Jalapeno and Other Types!