To make dairy kefir at home, there are only a couple of supplies you will need to gather: a culturing container and a cover for the container. Beyond that everything else is optional.
Milk Kefir Container
There are many conainers to choose from, but some materials are clearly superior to others.
- Glass. Glass is hands-down the best option for brewing kefir. Glass won’t react to the acidity of the brew. Glass doesn’t scratch easily, nor does it contain chemicals such as BPA. Glass containers are relatively easy and inexpensive to obtain. Canning jars are a great option.
- Plastic. Although technically plastic can be used to brew kefir, we do not recommend it for several reasons. First, plastic can be damaged, and scratches in the plastic can harbor foreign bacteria. Second, plastic (even food-grade plastic) often contains undesirable chemicals that can be harmful to the kefir grains.
- Ceramic. Do not use ceramic, as most of the glazes used to coat ceramic contain lead.
- Porcelain. Food-grade porcelain is generally safe for brewing kefir. Avoid porcelain pieces such as vases or decorative pottery that are not-food grade.
- Crystal. Crystal contains lead. Do not use crystal to brew kefir.
- Metal. Metal is generally detrimental to kefir and should not be used as a culturing vessel or for any item that will have contact with the kefir grains. The only exception is stainless steel. While we do not recommend using it, some people do have success doing so.
Kefir can be made in a any size jar. When choosing the size of your culturing container, consider how much kefir you will consume, as each batch of kefir will culture in 24 hours or less. It is better for the health of the kefir grains to continually make small batches than to make large batches and take breaks.
Covering Milk Kefir During Fermentation
- The cover should allow the culture to breathe.
- Effective coverings include tight-weave dish towels or fabric, a paper towel, a paper coffee filter, etc.
- The cover should be secured with a tight rubber band, to keep out pests such as ants or fruit flies.
- Avoid loose-weave fabric and screens.
- While a tight-fitting lid should not be used during the fermentation process, it is handy to have a lid for storage after fermentation is complete. Plastic bpa-free lids are avialable for both wide-mouth and regular-mouth canning jars, which are commonly used for culturing milk kefir.
Using a Plastic Strainer
Once the kefir has finished culturing, there are several ways to remove the kefir grains so they can be placed in fresh milk. We recommend a Plastic Fine Mesh Strainer as the best option, especially when working with new grains.