More than 500 years ago, the English chronicler Robert Fabyan described the science and art of vitreous (porcelain) enameling on metals, a practice that was already 15 centuries old. Today, vitreous enamel art is as vibrant as then. The industry of enameling metal panels, which blossomed in the 1800s and 1900s, had receded but is enjoying a resurgence thanks to new technological developments.
The Science of Vitreous Enamel: Boric Oxide Is Required
Vitreous enameling—the fusing of a thin layer of glass to a metal base—is virtually impossible to achieve on large areas unless the glass has a high (up to 25%) boric oxide content. From the day of its invention, enamel has been used to beautify metal objects, and once the technology had developed to allow its application to large pieces, its durability and protective power could be exploited.
Traditionally, an enamel surface is two coats, base and cover, each of which had to be applied and fired separately. But in the 1970s, the so-called 2C/1F process—two coats, one firing—was perfected. This technique decreases energy usage and process times dramatically. With advances in frit technology, the need for steel pre-treatment by pickling and nickel plating became unnecessary. As a result, effluent disposal costs and potential environmental risks are mitigated.
Enamel Glaze: Versatile and Beautiful
As a surface coating, especially iron and steel, vitreous enamel is unassailable. Highly durable with a long service life, it resists scratching and chemical marring. It is easy to clean, and therefore, very hygienic.
Microwave ovens are usually lined with plastic, stainless steel, or a painted surface. Okay for the basic process, but since integrated functions such as a grill, air circulation, and steam heating have been added, temperatures in the chamber can rise to 572°F (300°C) or more. Higher temperatures can result in staining, yellowing, and distortion. If an enamel lining is used, these faults are avoided altogether.
An added bonus is that because enameled steel has half the thermal conductivity of stainless steel, it actually improves food quality. This lower conductivity means less energy usage for the same cooking effect, shorter cooking times, and more vitamins retained in the cooked food.
This article comes from borax edit released