In a large pot, stir together the corn oil, cider vinegar, sugar, and ketchup until sugar has dissolved completely. Bring to a boil, then add the jalapeno peppers. Reduce heat to low, and simmer for 10 minutes. Season with oregano and garlic.
Ladle into sterile pint jars, leaving 1/4 inch of space at the top. Wipe rims with a clean dry towel. Seal with lids and rings. Process in a hot water bath for 10 minutes to seal. Refrigerate any unsealed jars.