Sometimes you may experience cream, brown or black colored deposits on the outside of the pot while cooking and here’s why this happens:
Pots made from 100% primary clay, because of its purity and negatively charged ions has been used to extract toxins for many centuries. When heated, this fired clay is negatively charged and, if there are any toxins in the food – either from additives in the water, animal fat (most animals store toxins in the fat), pesticides, fertilizers, heavy metals from vegetables, lentils, beans all of which are positive ions, Or if soap is used for cleaning, get squeezed out through the negatively charged clay platelets. Since the pot is unglazed these toxins get pushed out all the way to the outside walls of the pot.
Nothing sits within the walls and none of it goes back inside as pressure moves from high to low. The deposits have a sour, acidic, metallic taste. They come off easily when wiped with a piece of cloth and/or when the pot is washed after cooking.
In most cases this happens only when new. In a few uses the pot shrinks slightly and this will stop.
For Further Reading: Dioxins in animal’s fatty tissue: Dioxins and the effects on human health. According to the FDA, most human exposure to dioxins comes from food, with 95 percent of that coming from animal fats (FDA 2004a). (See more at: Antibiotics, toxins & hormones —Toxins and dioxins from food). It is some of these elements that the pot extracts.
In our testing and experience, changing water to filtered water has sometimes eliminated this issue. Also, changing from non-organic to organic ingredients has help reduce and eventually stop this. And not using any commerical soap for cleaning, has helped. Cleaning is a breeze and baking soda is enough.
Also, please note that if you have changed water upon noticing this, it may take 1-2 uses before the oozing stops. Well water or even water in some cities have a higher concentration of metals, chlorine, chloramine etc. and they are removed this way.
When some chemical ingredients like pectin or other additives etc. are used, this could happen also (like when making jellies).
If you see this happening a lot, and you have addressed the cause, it is a good idea to clean the pot in the following manner before continuing to cook in them.
Please wash the pot thoroughly and steam water in it without lid. Typically, the pot pushes out toxins, but when steaming water with lid open it will pull-in anything in the walls. After steaming, pour water out while still warm and wipe dry with cotton cloth. Set it aside to dry for about 10-15 minutes before using again.