Rice paper
Rice paper usually refers to paper made from parts of the rice plant, like rice straw or rice flour. However, the term is also loosely used for paper made from or containing other plants, like hemp, bamboo or mulberry.
Rice paper plant
In Europe, around the 1900s a paperlike substance was originally known as rice paper, due to the mistaken notion that it is made from rice. In fact, it consists of the pith of a small tree, Tetrapanax papyrifer, the rice paper plant.
The plant grows in the swampy forests of Taiwan, and is also cultivated as ornamental plant. In order to produce the paper, the boughs are boiled and freed from bark. The cylindrical core of pith is rolled on a hard flat surface against a knife, by which it is cut into thin sheets of a fine ivory-like texture.
Dyed in various colors, this rice paper is extensively used for the preparation of artificial flowers, while the white sheets are employed for watercolor drawings. Due to its texture this paper is not suited for writing.
Mulberry Paper
See also Washi
The sort of paper that many people think of when hearing the term “rice paper” (smooth, thin, crackly, strong) is not actually made from rice at all. The paper is made from fibers from the bark of the mulberry tree. It got the name “rice paper” because it was used to make packets for rice. This sort of paper is used for origami, calligraphy, paper screens and clothing, etc. It is much stronger than commercially made wood-pulp paper. Although paper can be made from rice straw, this is not the “rice paper” that people usually think of.
The correct name for this type of paper is, depending on the type of mulberry used, kozo (Broussonetia papyrifera, the paper mulberry), gampi (Wikstroemia diplomorpha), or mitsumata (Edgeworthia chrysantha). The fiber comes from the bark of the mulberry, not the inner wood or pith, and traditionally the paper is made entirely by hand.
The branches of the mulberry shrubs are harvested in the fall, so the fiber can be processed and the paper formed during the cold winter months, because the fiber spoils easily in the heat. The branches are cut into sections two-three feet long and steamed in a large kettle, which makes the bark shrink back from the inner wood, allowing it to be pulled off like a banana peel. The bark can then be dried and stored, or used immediately. There are three layers to the bark at this stage: black bark, the outermost layer; green bark, the middle layer; and white bark, the innermost layer. All three layers can be made into paper, but the finest paper is made of white bark only.
If the bark strips have been dried, they’re soaked in water overnight before being processed further. To clean the black and green bark from the white bark, the bark strip is spread on a board and scraped with a flat knife. Any knots or tough spots in the fiber are cut out and discarded at this stage.
The scraped bark strips are then cooked for two or three hours in a mixture of water and soda ash. The fiber is cooked enough when it can easily be pulled apart lengthwise. The strips are then rinsed several times in clean water to rinse off the soda ash. Rinsing also makes the fiber brighter and whiter—fine kozo paper is not bleached, it’s naturally pure white.
Each bark strip is then individually inspected, by hand, against a white background or lit from behind by a lightbox. Any tiny pieces of black bark and other debris are removed with tweezers, and any knots or tough patches of fiber missed during scraping are cut out of the strips. The ultimate goal is to have completely pure white bark.
The scraped, cooked, and cleaned strips are then laid out on a table and beaten by hand. The beating tool is a wooden bat that looks like a thicker version of a cricket bat. The fibers are beaten for about half an hour, or until all the fibers have been separated and no longer resemble strips of bark.
The prepared fiber can now be made into sheets of paper. A viscous substance called formation aid is added to the vat with the fiber and water. Formation aid is polyethylene oxide, and it helps slow the flow of water, which gives the papermaker more time to form sheets. Sheets are formed with multiple thin layers of fiber, one on top of another.
Edible paper
Some sorts of rice paper are edible, e.g. paper from rice flour, and are used for wrapping up food.
This paper is also used for cooking, e.g. summer rolls. Here the paper is put into lukewarm water, and the water dripped off before proceeding. In many places edible rice paper is available packaged in Asian food stores.
The main raw material used for producing this rice paper is white rice. White rice powder is refined and added with suitable tapioca proportion powder to make rice paper glutinous and smooth. The quality rice with traditional method in manufacturing made transparent rice paper delicious.
To make rice paper, rice is first soaked for 3 hours. Then, the soften rice is grind to powder and strained to remove unwanted particles. It is then soaked and squeezed to remove acidic substances. The remaining paste is then spread thin evenly on a surface, heated with steam, and left to dry to form rich paper[1].
Rice Straw Paper
Rice straw can be processed into simple paper, which is used as cigarette paper, for lamp shades or partition walls. Finer paper also can be made from it, especially together with other sorts of cellulose, like hemp.
References
- ^ Rice paper production process at CHANH KHANG