Kashering

A Crystal-Clear Halachic Approach to Glass

By: Rabbi Tzvi Rosen

Published Spring 2016

Glass is one of nature’s most versatile products created from some of nature’s most prevalent raw materials: sand, soda and lime. In the food industry, glass applications are extremely diverse. Glass can be made into delicate drinking glasses, as well as tough heat resistant ceramic cooktops tops withstanding temperatures over 1000°F.
How is glass made? Basically, the raw ingredients are heated and melted in a large furnace. The molten glass is shaped, blown, or pressed into its desired shape. The finished product is then annealed in an annealing oven and tempered to give the newly formed glass strength and durability.
Although glass can be made to be stronger and less porous than steel, the halachic status of glass remains enigmatic. On the one hand, Chazal recognized the fact that glass is tough, resistant and non-porous. On the other hand, glass raw materials are the same as earthenware which is very […]

Preparing/Kashering the Pesach Kitchen

By: Rabbi Moshe Heinemann

See How to Clean/Kasher Kitchen Items for Pesach Checklist here.

As the Yom Tov of Pesach nears, and the diligent balabusta begins to tackle the challenge of preparing the kitchen for Pesach, undoubtedly the light at the end of the tunnel is beginning to shine. Although moving into a separate Pesach home sounds very inviting, such luxuries are often not affordable and definitely not in the Pesach spirit. Among the basic mitzvos of the chag is the mitzvah of tashbisu se’or mibateichem, ridding one’s home and possessions of chometz. However, if we are to use kitchen equipment, utensils, or articles that can be found in our kitchen year-round, it may be insufficient to just clean them thoroughly. One is forbidden to use these items unless they have been especially prepared for Pesach. This preparation process is known as kashering.

The Torah instructs us that the proper kashering method used to rid […]