Pickling and Fermenting are next in complexity.
Pickles need either salt or vinegar to make. Salt, as we've seen above, is often used to dry foods. When added with a liquid, fermentation occurs, preserving and changing the food to something different. We typically think of Sauerkraut when we think of fermented food, but olives, Kimchee, and other foods are also produced.
By fermenting foods added, usually healthy, microbials are developed in foods. We call these probiotics and they promote health in the body and often actively fight disease.
Pickling with vinegar produces what we typically think of as "Pickles" whether soft or crunchy.
The ratio of salt, vinegar, salt and spices produces the different foods we associate with pickles.