especially those bulging from the pressure of gases produced by bacterial growth, should be discarded The low pH (high acidity) of tomatoes and many common fruits inhibits the growth of botulism bacteria, so these foods require the least severe canning treatment, usually about 30 minutes in a bath of boiling water to heat the contents to 185–195ºF/85–90ºC Most vegetables, however, are only slightly acid, with a pH of 5 or 6, and are much more vulnerable to bacteria and molds They’re typically heated in a pressure cooker at 240ºF/116ºC for 30 to 90 minutes Chapter 6 A Survey of Common Vegetables Roots and Tubers Potatoes Sweet Potatoes Tropical Roots and Tubers The Carrot Family: Carrots, Parsnips, and Others The Lettuce Family: Sunchoke, Salsify, Scorzonera, Burdock Other Common Roots and Tubers Lower Stems and Bulbs: Beet, Turnip, Radish, Onion, and Others Beets Celery Root The Cabbage Family: Turnip, Radish The Onion Family: Onions, Garlic, Leeks Stems and Stalks: Asparagus, Celery, and ... Scorzonera, Burdock Other Common Roots and Tubers Lower Stems and Bulbs: Beet, Turnip, Radish, Onion, and Others Beets Celery Root The Cabbage Family: Turnip, Radish The Onion Family: Onions, Garlic, Leeks... A Survey of Common Vegetables Roots and Tubers Potatoes Sweet Potatoes Tropical Roots and Tubers The Carrot Family: Carrots, Parsnips, and Others The Lettuce Family: Sunchoke, Salsify, Scorzonera, Burdock... The Cabbage Family: Turnip, Radish The Onion Family: Onions, Garlic, Leeks Stems and Stalks: Asparagus, Celery, and