Parchment paper

Parchment paper and bakery release paper are cellulose-based papers that are used in baking as a disposable non-stick surface. Both are also called bakery paper or baking paper. They should not be confused with waxed paper, also known as wax paper or rarely as butter paper.

Modern parchment paper is made by running sheets of paper pulp through a bath of sulfuric acid (a method similar to how tracing paper is made) or sometimes zinc chloride. This process partially dissolves or gelatinizes the paper. This treatment forms a sulfurized cross-linked material with high density, stability, and heat resistance, and low surface energy—thereby imparting good non-stick or release properties. The treated paper has an appearance similar to that of traditional parchment, and because of its stability is sometimes used for legal purposes where traditional parchment was used.

The stickless properties can be also achieved by employing a coated paper, for which a suitable release agent—a coating with a low surface energy and capability to withstand the temperatures involved in the baking or roasting process—is deposited onto the paper's surface; silicone (cured with a suitable catalyst) is frequently used.

A common use is to eliminate the need to grease sheet pans and the like, allowing very rapid turn-around of batches of baked goods. Parchment paper is also used to cook en papillote, a technique where food is steamed or cooked within closed pouches made from parchment paper.

Bakery paper can be used in most applications that call for wax paper as a non-stick surface. The reverse is not true, as using wax paper will cause smoke in the oven and affect taste.

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