What is Jute Grading?
Jute is an important but coarser natural vegetable fiber under the category of bast fibers like flax, hemp, kenaf and ramie. Jute fiber mainly used for packaging and other diverse textile and non-textile applications including technical textiles. Since ancient times, it has been traditionally grown in the eastern part of the Indian subcontinent, which make up of the present day West Bengal of India and plains of Bangladesh.
Jute fiber extracted by the retting process from the bast of the parent plant comes in the form of long mesh of interconnecting fibers commonly known as jute reed. The jute reed is usually 6–15 feet long. Typical yield of jute fiber based on weight of stem from which it is derived is about 6%. The top of jute reed is thinner than the root. The reeds are then split-opened in carding machine into the component fibers called the spinner’s fiber.
Jute grading is crucial because it determines the quality and price of the fiber. Grading classifies jute based on specific characteristics. The main factors are color, strength, fineness, length, and cleanliness. These factors affect the fiber’s usability in different products. Generally grading of jute fiber is done after the barky ends are cut off. There are six grades both for White and Tossa jute. The characteristics specified for various grades are given below.
Grading System of Jute Fiber:
Jute fibers are graded according to three qualities of fibers. They are-
On a basis of fiber properties:
- Length
- Strength
- Fineness
- Color
- Luster
- Roots and cleanliness and uniformity in color.
On the basis of color:
There are two colors-
- White and golden
- Brown to red Corresponding to the main varieties capsularies and olitorius.
On the basis of export:
- A bottom
- B bottom
- C bottom
- X bottom
On the basis of quality of raw jute:
- Pucca grading
- Kutcha grading
A. Pucca Grading:
Raw jute from which roots have been cut.
White jute:
Bangla white special (BWS):
- White or creamy
- Finest texture
- Very good luster, clean, well hackled
- Completely free from any defects
- Entirely free from red ends
Bangla White-A (BW-A):
- White to light cream
- Fine texture
- Strong and very good luster, clean
- Completely free from red ends and any blemish
Bangla White-B (BW-B):
- Light cream to straw color
- Good texture
- Strong and good luster, well hackled
- Free from blemish and red ends excluded
Bangla White-C (BW-C):
- Light grey or light reddish to straw color
- Sound strength
- Average luster
- Clean but free from croppy or hard gummy
- Tops and roots and red soft ends are permissible.
Bangla White-D (BE-D):
- Any color
- Average strength
- Occasional bark and specks permissible
- Slightly croppy and gummy tops permissible
- Red ends also permissible
Bangla White-E (BW-E):
- Any color
- Any strength but free from perished fibers
- Unretted jute
Tossa Jute:
Bangla Tossa Special (BTS):
- Uniform golden or reddish color
- Finest texture
- Very strong
- Very good luster
- Clean cut and well hackled
- Completely free from any defects.
Bangla Tossa-A (BT-A):
1 .Uniform sliver grey to golden color
- Fine texture
- Strong and good luster
- Clean cut and well hackled
- Completely free from any blemish.
2.Uniform light golden to reddish color
- Fine texture
- Strong and good luster
- Clean cut and well hackled
- Completely free from any blemish.
Bangla Tossa-B (BT-B):
1. Light to medium grey color
- Sound clean
- Good texture
- Average luster
- Clean cut and well hackled
- Free from any defects
2.Light grey or reddish excluding dark gray color
- Sound clean
- Good texture
- Average luster
- Clean cut and well hackled
- Free from any defects
Bangla Tossa-C (BT-C):
- Mixed colors
- Average strength
- Occasional bark and soft specks allowable free from runners
- Slightly croppy and gummy tops permissible
- Well cut and hackled but free from black root ends.
Bangla Tossa-D (BT-D):
- Mixed colors
- Average strength
- Occasional bark and specks allowable
- Free from runners
- Croppy and gummy tops permissible
- Rough cut and hackled
- Free from black root ends
Bangla Tossa-E (BT-E):
- Any color
- Any strength but free from unretted jute
- Stick and perished fibers
- Rough cut and hackled bark and hard center permissible
Kutcha Grading:
Raw jute from which roots have not been cut.
Kutcha bales are graded as follows-
- Tops
- Middle
- Bottoms
- B-bottoms
- C-bottoms
- X-bottoms
- Habijabi
1. Tops:
- Very strong fiber
- Excellent color and luster
- Free from all defects
- Cutting not more than (White 15%, Tossa 10%)
2. Middle:
- Strong sound fibers
- Average color and luster
- Free from all specks runners and harsh crop end (White 25%, Tossa 15%)
3. Bottoms:
- Sound fibers
- Medium strength
- Free from all hard centered jute (White 30%, Tossa 20%)
4. B-bottoms:
- Sound fiber
- Medium strength
- Not suitable for higher grade(White 35%, Tossa 25%)
5. C-bottoms:
- Medium strength
- Any color
- Free from runners and choppiness.
6. X-bottoms:
- Weak, harsh jute
- Free from tangled jute and stick
7. Habijabi:
- Tangled jute
- Free from any dust and cuttings
Classification of jute according to the quality (Geographical distribution according to Bangladesh):
- Jat
- District
- Northern
A. Jat:
Jat is the finest quality jute with firm. It has good color and length. It has good luster. This type of jute fiber grows in the district of Mymensingh, Dhaka and Comilla.
B. District:
District jute is close to jat in quality. The fiber is not uniform in textures and strands. Its color varies from light ream to dull grey. Its length is shorter. There are two types of District jute. They are-
- Hard district
- Soft district
Hard district: The hard district jute is better than the soft district. It mainly grows in the district of Faridpur
Soft district: This type of jute grows in district of Noakhali, Pabna, Barisal, Jessor, Khulna, Sylhet, Lower Comilla, Chittagong and some part of Dhaka.
C. Northern:
Northern jute is of somewhat inferior quality. The fiber is dull-colored fluffy hairy and barky. Generally medium length and weak. This type of jute grows in District of Rangpur, Dinajpur, Bogra and Rajshahi.
You may also like: Defects of Jute Fiber: Causes and Remedies
Conclusion:
Jute fiber is graded based on several quality parameters, including color, strength, length, fineness, and defects. It is essential for determining its quality, market value, and suitability for various applications. Proper grading helps in maintaining quality consistency and enhances the commercial value of jute in global markets.
References:
- Ghosh, S. K. (2016). A Technical Handbook on Bituminized Jute Paving Fabric (BJPF): a partial substitute and reinforcement of bitumen mastic.
- Kozlowski, R. M., & Mackiewicz-Talarczyk, M. (2020). Handbook of Natural fibers: Volume 2: Processing and Applications. Woodhead Publishing.
- Advances in jute research. (2019).
- A Comprehensive Study on Jute Fiber Edited by Shamsuddin Muttaki. (n.d.).
Founder & Editor of Textile Learner. He is a Textile Consultant, Blogger & Entrepreneur. Mr. Kiron is working as a textile consultant in several local and international companies. He is also a contributor of Wikipedia.
