Grease-proof paper is an essential item in many industries, from food packaging to baking. It ensures that oil and grease do not seep through, maintaining the integrity and cleanliness of the product. One popular type of grease-proof paper is vegetable parchment, which is created through a unique process.

Vegetable parchment is made by treating a paper of pure cellulose with sulfuric acid. This treatment causes the fibers to swell, resulting in a homogeneous film. The end product is a sturdy and durable paper that is resistant to grease and oil. Vegetable parchment is available in various weights, ranging from 40 to a maximum of 200 grams per square meter.

While vegetable parchment is an excellent option for grease-proof paper, it can be quite expensive. However, there is a more affordable alternative called glassine. Glassine is created by refining the paper stock, reducing its porosity. This refined paper is then further improved in density through a process called supercalendering. The result is a sheet of paper with extremely low porosity and enhanced grease resistance.

To make glassine even more resistant to grease, the paper can be treated in the size press. This involves applying starches, alginates, or CMC (carboxymethyl cellulose) to the paper, filling the pores and making the fiber surface fat repellent. This additional treatment ensures that the paper remains grease-proof and maintains its integrity during use.

Glassine is typically produced in lower basis weights than vegetable parchment, usually ranging from 30 to 50 grams per square meter. This is due to the difficulties in dewatering the paper during the manufacturing process. Despite its lower weight, glassine still offers excellent grease resistance and is widely used in various industries.

Grease-proof, vegetable parchment and glassine papers play a crucial role in ensuring the quality and cleanliness of products. From food packaging to baking, these papers provide a barrier against grease and oil, preventing any contamination. Whether it’s wrapping a sandwich or lining a baking tray, grease-proof papers are a reliable and essential item in everyday life.