sour milk
Perhaps you mean to ask for foods made using bacteria?
Actually canning foods is a way to kill off bacteria so that they will last a long time. But some foods are made by using bacteria and then those foods are sterilized while being canned. Sauerkraut and pickled foods are prepared this way. But the bacteria don't sterilize the food,the high heat does.
yogurt
Yes some bacteria can be good. Like the type that are in foods.
You can find bacteria in anything that has not been properly stored.
Some examples of foods made with bacteria include yogurt, cheese, sauerkraut, kimchi, and sourdough bread. These foods undergo fermentation processes where beneficial bacteria are used to transform the ingredients into the final product.
cellulose
chocolate cake
Lactic acid bacteria, such as Lactobacillus and Leuconostoc species, are commonly used to decompose waste and produce fermented foods. These bacteria convert sugars into lactic acid through fermentation, which helps preserve food and gives it a characteristic flavor. Examples of fermented foods produced by these bacteria include yogurt, sauerkraut, and kimchi.
Foods like yogurt, kefir, sauerkraut, kimchi, and miso contain beneficial bacteria that can improve gut health.
Foods that can effectively kill bacteria in the stomach include garlic, honey, and ginger. These foods have natural antibacterial properties that can help fight off harmful bacteria in the digestive system.
I had to do a project about foods without bacteria. To be honest, there is absolutely no food without bacteria. Bacteria is everywhere, inside you around you. THERE IS NO ESCAPE! I myself searched for hours on this subject, and still didn't have any luck with the topic. I am sorry that I couldn't have help you more. :'/