As mentioned above cheesecloth fabric is made from undyed cotton. The threads are loosely woven so that the fabric appears porous. Its porosity is very useful in straining of foods. There are several grades and types of cheesecloth. The grade of the cheesecloth is mainly based upon the number of threads per inch. There are about five grades of cheesecloth, namely, #10, #40, #50, #60 and #90.
Cheesecloth is mostly used for culinary purposes. Hence, it can be easily found in supermarkets or grocery stores. Look for cooking gadgets and kitchen supplies in the cooking section. Cheesecloth is mostly stocked around this stuff. You can also buy cheesecloth at fabric stores or stores that stock sewing stuff. Some bed linen stores may also stock cheesecloth of certain grades. You may not find the cheesecloth of required grade at a supermarket or grocery store. The cheesecloth that supermarkets sell is mostly soft and loosely woven. Thus, you might have to fold it in layers for achieving the desired thickness or size of holes. The maximum variety of cheesecloth can be found on the Internet, as you can order the cheesecloth of any grade as per your requirements. Go through the catalogs on various shopping websites and order the cheesecloth as per your requirements. One can also find cheesecloth at upmarket cuisine boutiques, albeit at a very high price.
Many a time your recipe demands use of cheesecloth, to which you may not have an easy access, in such cases cheesecloth substitutes can come in handy. There are many materials that work just as fine as cheesecloth for a myriad recipes. Muslin cloth is an ideal substitute for cheesecloth, due to their similar texture. You may use medical gauze for the same purpose. However, you may have to fold it in several layers for achieving a desired effect, as medical gauze is very loosely woven with large hole sizes. An old sock and a worn out linen also work great as cheesecloth alternatives, however make sure both are sufficiently clean to be used for cooking purpose. Similarly, a coffee filter (paper) can also be used as cheesecloth substitute as it offers same porosity. Any of these materials can be used depending upon the thickness of cloth demanded by your recipe.