Freezing is the only way to preserve eggplant. There are no canning instructions.
Use frozen raw eggplant in dishes where it does not need to stay firm such as soups, stews, sauces, and dips.
Cooked eggplant, such as roasting, may be frozen to use in dips or sauces.
Consider the age, size, and variety of eggplant you are using. Small thin varieties may have tender skin and not require peeling. Older larger varieties with more seeds may have a bitter taste; those slices may be salted to draw out bitter juices.
Source: Penn State University Extension Food Preservation