kostutuskiviä

Kostutuskiviä, literally meaning "moisturizing stones" in Finnish, are a traditional Finnish method for keeping baked goods, particularly bread, moist. They are typically small, unglazed ceramic or earthenware pieces, often disc-shaped or rectangular, designed to absorb and slowly release moisture. Historically, they were a common item in Finnish kitchens.

The principle behind kostutuskiviä is simple humidity control. A dry kostutuskivi would be briefly soaked in water and then placed inside a bread box or a container with freshly baked bread. As the bread naturally loses moisture, the ceramic stone, still slightly damp, would provide a humid microenvironment, preventing the bread from becoming stale and hard too quickly. This was especially useful in times before modern refrigeration and airtight packaging were commonplace.

While their popularity has waned with the advent of advanced food storage solutions, kostutuskiviä are still appreciated by some for their natural, eco-friendly approach to food preservation. They are sometimes seen as a charming, nostalgic kitchen tool, connecting users to traditional Finnish culinary practices. Modern versions are available, often with decorative designs, but their function remains the same: to maintain a gentle level of humidity around stored bread.