Yes, provided that acetic acid or vinegar is the active preserving agent. The presence of salt or other minor ingredients does not disqualify a product from heading 2001 as long as the vinegar or acetic acid is what preserves the goods. If the product is preserved primarily by salt or fermentation without acetic acid, it would fall under a different heading.

Capers preserved in vinegar or acetic acid fall under 200190, the NESOI subheading, because they are neither cucumbers nor gherkins. The 200110 subheading is limited to cucumbers and gherkins specifically.