Why does garlic turn green during storage?

The green color of garlic that occurs during storage in my kitchen indicates quality degradation. The color change is a result of chlorophyll production due to light exposure. Green garlic is bitter and shows signs of marking too early in the process. Knowing how to deal with this reaction will help you maintain the quality and flavor of your rescue garlic.

Similar to potatoes' greening, light activates enzymes in the garlic cloves. Even a brief exposure once it starts to sprout will initiate this process. The green indicates that sprouting has begun, causing the flavor compounds to move around. I've since started storing garlic in opaque containers after having issues like this, losing several bulbs, as the shelf life of garlic in a container is indefinite when stored in the refrigerator. Complete darkness will completely prevent chlorophyll activation.

Don't let greening happen right from harvest. Cure the bulbs in complete darkness for 3 to 8 weeks. Avoid placing garlic near windows during this step. I use blackout curtains in my curing room. After curing, transfer right away into opaque containers like ceramic crocks or wooden boxes.

Temperature affects greening, too; store garlic at 60-65°F to delay sprouting. Do not refrigerate - the cold shock increases chlorophyll production. My pantry shelf maintains optimal conditions throughout the year. To monitor humidity, use a hygrometer. Keep it at about 60%.

Fully green cloves should be discarded immediately, as they will turn bitter. Partially green cloves can be used in long-cooked applications, such as stews, where the bitterness mellows. Make a note of where greening happened to adjust your storage method next season. A little careful handling will ensure you enjoy fresh and tasty garlic for a while.

Read the full article: When to Harvest Garlic and How to Do It Right