AMERICAN poet William Carlos Williams wrote: “Old age is a flight of small cheeping birds skimming bare trees above a snow glaze.”
Many Filipinos may not know how a snow glaze looks like; but one common glaze that Filipinos are familiar with can be seen in furniture. And we call that glaze “shellac.”
What most Filipinos, even those who have actually seen a snow glaze, may not know is this: the glaze of shellac has been fairly used in pharmaceutical products. The flakes come from the resin that the female Laccifer bug (Kerria lacca or just lac) secrete on trees in the forests of India, Thailand and Burma (now Mynmar). It takes about 100,000 lac bugs to make 500 grams of shellac flakes.
Shellac is a natural bioadhesive, chemically similar to the synthetic polymers we call “plastic.” In a sense, shellac is a natural form of plastic. And it is used as a glazing agent on tablets and capsules. It contains denatured alcohol, which dissolves the 20-51 percent shellac component.
It has acidic properties that make it resistant to stomach acids, and is a useful coating for controlled-release tablets. It protects the tablet from moisture, extends its shelf life, among others.
The United States Food and Drug Administration classified shellac as "generally recognized as safe" (Gras). However, a study conducted by the Food and Drug Research Laboratories in 1984 noted enlargement of... [READ MORE]
This article appears in SunStar Cebu newspaper on 13 March 2013.
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