If you regularly buy food from supermarkets, you’ve probably seen the OU symbol on various products and wondered what it means.

These mysterious markings are called hechsher symbols and understanding them is very important to a consumer.
A hechsher is a special product certification, qualifying foods that conform to kosher requirements. Kosher-certified companies have to meet the highest standards of product quality as well as maintaining the best manufacturing practices.

Hechsher certification brings strict requirements to the quality of finished products as well as their ingredients. That is why production lines and equipment used to manufacture kosher foods are thoroughly cleaned and purged. Even the smallest amount of a non-kosher substance is not allowed. Products may be rendered non-kosher if the utensils and equipment were not clean.

Kosher dietary laws identify three classifications of foods: meat, dairy, and “neutral“ foods, also called pareve. The hechsher itself isn’t a signifier of hypoallergenic foods. However, ”neutral" products are helpful to people who are allergic to dairy or meat because pareve indicates food is free of milk products and meat.

There are many kosher certification agencies out there granting a hechsher to packaged foods and beverages. The most common symbol of kosher-quality products is a capital U inside a circle or the OU sign that stands for the Union of Orthodox. This marking can be found on the packaging of Coca-Cola, Nestlé, Jim Beam, Heinz, and other world-known brands. The small letter next to the OU symbol indicates the type of product:

OU — the food contains neither meat nor dairy and is therefore a "neutral" product
OU-D — dairy product
OU-M (OU-Glatt) — the product is made with meat or meat ingredients
OU-F — the product is made with fish ingredients

People who are allergic to milk or meat. Pareve products contain no meat or dairy and so they may be consumed by vegetarians and people with lactose intolerance.
People who are dieting or exercising regularly. Kosher products are a great choice for them.
People who want to be sure that they buy healthy and high-quality food.