Durian is an important cash crop and a champion product in Thailand. It is planted in every region of the country, mostly in the east and the south. Some 70 percent of durian production, in each season, is consumed domestically as fresh fruit; 20 percent exported; and 10 percent as durian processed products, such as deep-fried durian, durian jam, etc.
During the durian season, durian rinds accumulate in high piles as vendors usually remove the rinds for buyers’ convenience. In addition to ripe durian rind, raw durian rinds are also left unattended after the flesh has been removed for processing as deep-fried durian. Rinds are considered as good for organic fertilizer, or firewood, but they are not easily disposed off.
The Post-Harvest and Products Processing Research and Development Office of the Department of Agriculture, Thailand, has developed a simple technology for the processing of durian rinds into paper.
Processing Durian Rinds into Paper
- Wash durian rinds in clean water and then soak them in 1 g, or one teaspoon, of potassium permanganate in 20 liters of water for about 30 minutes.
- Slice the soaked durian rinds into small pieces (Fig. 1).
- Tear paper, or newsprint, into small pieces and soak them for 24 hours.
- Weigh durian rinds and paper at a ratio of 7:1 or 1.75 kg durian rinds to 0.25 kg paper.
- Boil durian rinds (Fig. 2 and Fig. 3) in 4 liters of water for about one hour and leave to cool.
- Stir durian rinds, boiled water and paper together, put everything in a tank with 40 liters of water. Blend them together.
- Make a sieve using No. 16 nylon on a wood frame.
- Sieve the blended durian rinds and paper, grade filament consistently and all over the sieve. Thickness and neatness depends on graders’ skills.
- Dry the sieve in the sunshine for about 5 hours. Filament will be dried and paper can be removed from the sieve (Fig. 4).
- Keep the dried paper in a dry place for later use.
Paper made will be naturally brown. Dye can be added into the tank before sieving for a more colorful paper (20 g of dye/4 kg of raw materials).
Designs can be made by adding rose petals or leaves soon after sieving, but before drying it in the sunshine. Beautiful designs depend on the maker’s skills. Paper made from durian rinds is natural and has no caustic soda, thus safe to users.
Paper made from durian rinds offers tender filament and better quality than mulberry-pulp paper. Durian rinds may be blended with fruit or vegetable fibers to produce different kinds of paper. For instance, if blended with rambutan rinds, it will have a natural reddish color; with mangosteen rinds, a natural violet paper; with dragon fruit skin, a violet and tender paper.
The proportion of fruit, or vegetable fibers with durian rinds, depends on the type of fruit, or vegetable, but it should not exceed 50 percent of the total materials as it will affect the paper quality.
Durian rind papers can be made into photo frames, pencil cases, ornament cases, gift wrapping paper, etc. (Fig. 5).