Section 7.1: Working Safely with Yams #

Proper preparation makes yams safe to eat and visually appealing. Correct handling addresses cleaning, skin protection, oxidation control, and toxin removal.

Key Information: Peeling and cleaning is the first step in preparing most yam dishes.

Protecting Your Skin #

Certain yam varieties contain calcium oxalate crystals. These microscopic, needle-shaped structures can cause significant skin irritation.

Key Information: Gloves should be worn when peeling some varieties of yams because they may cause skin irritation due to calcium oxalate crystals.

Preventing Oxidation #

Once peeled, yam flesh reacts quickly with the air. This enzymatic browning or oxidation can discolor the tuber within minutes.

Key Information: After peeling but before cooking, yams should be stored in cool water with lemon juice or vinegar to prevent browning.

Adding a small amount of acid, like lemon juice, slows the enzyme activity while you finish preparation.

Handling Bitter Varieties #

Some species, such as Dioscorea dumetorum, contain toxic compounds that must be neutralized.

Key Information:

• Bitter varieties of yam require special processing to remove toxic compounds and make them safe for consumption.
• A common precaution when preparing bitter varieties is extended boiling with multiple water changes to leach out the toxins.

Changing the boiling water several times gradually removes these water-soluble toxins.

Cleaning the Skins #

When cooking yams with the skin intact—common for roasting—thorough cleaning is essential.

Key Information: When preparing yams with their skins, the skins should be thoroughly cleaned to remove soil contaminants.