Problem: Low Acid Foods – The trick to canning shelf-stable foods is the acidity. If you have the right amount of acidity, it creates an unpleasant environment for dangerous botulism bacteria to grow. When canning low acid foods such as green chiles, you need to either can them under pressure (using a pressure-canner), or if you use a simple water-bath canning process, add enough acidity to prevent bacteria from growing.
The problem with simply heating up the sealed jars is that during normal processing, the goal is to drive all air out of the headspace (the space between the food and the lid). That’s why you only put the lids on finger tight instead of cranking them on as tight as you can. While boiling, the air is forced out, and then the vacuum formed by lack of air sucks down the lid, making a tight seal. No air trapped in the top of the jar = no opportunity for microorganisms that need air to grow to spoil your salsa. If the pH is low enough, botulism (which releases spores in an anaerobic (no oxygen) environment) will also be out of commission. (For more on botulism in canning, read here – https://commonsensehome.com/botulism/.)
I fell in love with Mexican food during a 2003 trip to California. Head over heels in love. I’m not talking your Chipotle Mexican Grill nonsense or your Taco Bell Tex Mex disgrace, I’m talking the sight and sounds of your host family’s Latin American sister-in-law chopping up wine-ripened tomatoes and fresh Jalapeños for Pico de Gallo on Thanksgiving. I’m talking pounding Coronas with Rudy all day and talking cultural differences, dreams and life in general. I’m talking the sound of Mariachi bands playing tableside in a side alley eatery near LA’s historic Olvera Street. The banging of pots from the stuffed taqueria kitchen. The smell of the spices hitting the heat of the stove… I love Mexican food. The authentic kind of Mexican food that few of us get to experience and shockingly many of us never knew existed… THIS, the authentic and the real, I love it!