Fresno vs Jalapeño

The Fresno is the newcomer, and it has the paperwork. NMSU's Chile Pepper Institute dates it to 1952, when Clarence Brown Hamlin first grew it, and it is named for Fresno County, California. Ryan Bradley's 2018 history for Eater fills in the rest: Hamlin was a grower and seed merchant in Clovis, just outside the city of Fresno, his nephew still sold the seed decades later, and most people who think they have never eaten one have bought it mislabeled as a jalapeño. The Jalapeño is the old one. The INIFAP volume Cultivo del chile en México traces its name to Jalapa, Veracruz, where it was once grown and shipped to the rest of Mexico. Texas made it the state pepper in 1995.

Side by side they look like the same pepper and are not. The Chile Pepper Institute notes the Fresno's thinner walls and a more complex, fruity, smoky flavor when it ripens red, which is the stage it is usually sold at. It is more conical and the pods point up. The Jalapeño is thick walled, sold green, and its big ripe fruit can carry pale striations that INIFAP compares to the scales of a huachinango, the red snapper. A California grower told Eater the practical reason buyers pay for Fresnos in autumn: a red Fresno's skin does not crack the way a red jalapeño's often does.

On heat the WikiPepper ranges overlap, 2,500 to 10,000 for the Fresno and 2,500 to 8,000 for the Jalapeño, and the ripe red Fresno tends to the top of its band. Which one is hotter on a given day depends on the seed more than the name. Texas A&M's TAM Mild Jalapeño II measured 1,080 to 1,620 SHU in Texas trials against 19,980 for the hot standard 'Grande', so a jalapeño can sit well below a Fresno or well above it. Nobody has bred a mild Fresno, which is one reason its reputation is steadier.

Use is where the thin wall matters. The Fresno is at its best red and raw, sliced into salsas, pickled, or blended into sauces where its fruit shows. It is a poor stuffing pepper. The Jalapeño's thick flesh is why it is stuffed, grilled and pickled whole, and why its ripe pods can be smoke-dried into chipotle without collapsing. If a recipe calls for one and you have the other, the swap works in a salsa and fails in a popper.

Sources

• Chile Pepper Institute (New Mexico State University): Fresno
• Ryan Bradley, The Little Pepper That Could, Eater (11 July 2018)
• Zegbe Domínguez et al., Cultivo del chile en México (INIFAP / Universidad Autónoma de Zacatecas, 2012)
• PLANTanswers (Texas A&M horticulture): TAM Mild Jalapeno II release notes
• Texas State Library and Archives Commission: Texas State Symbols