The jalapeño is a medium-sized chili pepper pod type cultivar of the species Capsicum annuum. A mature jalapeño fruit (Yes, it's a fruit) is 5–10 cm (2–4 in) long and hangs down with a round, firm, smooth flesh. It is of mild to medium pungency, 2,500 and 10,000 Scoville* units in general. It is commonly picked and consumed while still green, but occasionally it is allowed to fully ripen and turn crimson red. It is milder than the Serrano pepper. Jalapeños are a good source of vitamin A and vitamin C. Jalapeños are considered to be high in antioxidants and are lower in capsaicin and in flavonoids than other peppers. Jalapeños are higher in vitamin E, vitamin K, and vitamin B6 than other peppers.
Compared to other chillies, the jalapeño heat level varies from mild to hot depending on cultivation and preparation and can have between 2,500 and 10,000 Scoville units*. The number of scars on the pepper, which appear as small brown lines, called 'corking', has a positive correlation with heat level, as growing conditions which increase heat level also cause the pepper to form scars. For US consumer markets, 'corking' is considered unattractive; however, in other markets, it is a looked for trait, particularly in pickled or oil preserved jalapeños
The Jalapeño is the state pepper of Texas adopted in 1995.
Jalapeños have flown in space, first reported as flying on the Space Shuttle Columbia during STS-5 in 1982, they were taken on board by William B. Lenoir given to him by fellow Astronaut Sherwood C. Spring "Woody", who had grown them, and the mission logs record: "...'tell Woody the jalapeños are outstanding.'
The Guinness World Records for most jalapeños eaten in a minute is 16 by Alfredo Hernandes on 17 September 2006 at La Costeña Feel the Heat Challenge in Chicago, IL, USA. Patrick Bertoletti holds the Major League Eating jalapeño records at 275 pickled jalapeños in 8 minutes on May 1, 2011, and 191 pickled jalapeños in 6.5 minutes on Sept. 16 2007 in the 'Short-Form'.
*Scoville units = the heat index for chili pepper - click below
See Scoville Chart