Using a stone pestle and mortar can indeed pose a risk of getting tiny rock particles in your food. However, this risk can be minimized with proper care and maintenance of the pestle and mortar.
To reduce the chance of getting ground-up rock in your food:
Choose the Right Material: When purchasing a stone pestle and mortar, opt for ones made from non-porous materials like granite, marble, or volcanic rock. These materials are less likely to break down and release particles into your food.
Season the Mortar: Before using the stone mortar for grinding food, it's a good idea to season it by grinding a handful of rice grains or salt into the mortar until the resulting powder appears clean. This process helps remove any loose particles and debris from the mortar's surface.
Avoid Grinding Hard or Abrasive Materials: Limit the use of the mortar to grinding soft foods, herbs, and spices. Avoid grinding particularly hard or abrasive materials that could cause the mortar to break down more quickly.
Regular Cleaning and Maintenance: After each use, wash the mortar with warm water and mild soap to remove any food residues. Be sure to thoroughly dry it to prevent moisture from seeping into the stone and causing it to degrade. Additionally, store the mortar in a dry and well-ventilated place.
Replace When Necessary: Over time, even with proper care, stone pestle and mortars can wear down. If you notice significant wear or signs of degradation, consider replacing the mortar to ensure food safety.
If you are concerned about potential rock particles or simply want to avoid any risks associated with stone pestle and mortars, you can opt for alternative materials like ceramic, porcelain, or metal mortars, which are less likely to break down and contaminate your food. Always make sure to choose kitchen utensils that are safe, durable, and appropriate for your culinary needs.