Vinegar

A two-fermentation product

Vinegar production has two stages:

1. Alcohol fermentation — yeasts convert sugar to ethanol (making wine, beer, cider, etc.).
2. Acetic fermentation — Acetobacter bacteria convert ethanol to acetic acid, producing vinegar.

The starting alcoholic beverage determines the vinegar’s character — wine vinegar tastes of grapes, cider vinegar of apples, rice wine vinegar of rice fermentation.

Major regional vinegars

• Balsamic vinegar of Modena — Italian. Traditional version is aged 12+ years in successively smaller wood barrels; modern commercial balsamico often uses cooked grape must with caramel and added wine vinegar.
• Apple cider vinegar — American, made from fermented apple cider. Folk-medicine reputation.
• White vinegar — distilled grain alcohol vinegar; most-used cleaning vinegar, pickling staple.
• Red wine vinegar — French, Spanish; used in vinaigrettes, marinades.
• Sherry vinegar — Spanish; aged like the wine, complex and nutty.
• Rice vinegar — Asian; milder than wine vinegars, used in sushi rice and dressings.
• Black vinegar (Chinkiang) — Chinese; aged, dark, malty-sweet, used in dumpling dipping sauces.
• Malt vinegar — British; from beer-base; the chip-shop classic.
• Coconut vinegar — Filipino, Caribbean; from coconut water or sap.

What it does in cooking

Vinegar performs several culinary roles:

• Brightens rich or fatty dishes (a splash transforms a heavy stew).
• Tenderizes meat through acid denaturation.
• Preserves in pickles by lowering pH.
• Curdles milk to make ricotta or buttermilk.
• Deglazes pans with concentrated browned bits.
• Stabilizes egg-based emulsions like hollandaise.

A note on “raw”

Most commercial vinegar is pasteurized and filtered. Unpasteurized (“raw,” with the visible “mother” of bacteria) is sometimes marketed as more healthful — the science is mixed, but the unfiltered version does contain beneficial bacteria. The flavor difference is subtle.