How much must one eat to recite a brocha acharona? How much bread must one eat to fulfill one’s obligation of seudas Shabbos?
Although Chazal chose to describe measurements in terms of commonly used items or foods such as a k’zayis (olive) and a k’beitzah (egg), the size of a standard size egg 1800 years ago may have been larger than today’s egg. Similarly, there are many varieties of olives, and we are uncertain as to which one is used for the k’zayis measure. Therefore, shiurim must be defined in contemporary terms.1 The following is based on the psak of Rabbi Moshe Heinemann shlit”a.
I. K’zayis Measurement2 – 1.27 fl. oz. (38 ml) – If one eats a k’zayis3 of bread, he must recite birchas hamazon.4 Similarly, if one eats a k’zayis of any other food a brocha acharona must be recited.5
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Olive oil – the liquid gold of the ancients – was touted for its nutritional, medicinal, and cosmetic value. As a fuel, olive oil illuminated the home; as a food ingredient, it was a feast to the palate. Olive oil production is one of the world’s oldest industries which has not changed much over the millennia.
Numerous olive oil brochures of the Mediterranean coastal region proudly claim that the olive oil industry dates back to over 5,000 years. This is demonstrated by the discovery of a 5,000 year old olive oil earthenware vessel in Turkey. Shemen zayis, as mentioned in the Torah, is one of the seven special species of Eretz Yisroel. The Torah requires the purest of pure olive oil, shemen zayis zach, to light the Menorah. Olive oil was an integral part of the service in the Bais Hamikdash. The olive branch is considered a symbol of peace […]