GB 5991-2026Oriental tobacco - Grading technical requirements (English PDF)

6.1 Basic Requirements

6.1.1 The appearance quality factors of the aromatic smoke, such as its identity, structure, luster, oil content, color, and length, all meet the corresponding quality grade and are complete. Only when factors such as colorfastness, discoloration, defects, and blue content meet the relevant regulations can a grade be assigned. The quality level and unit of measurement for the grading factors should... It complies with the requirements in Table 2.

6.1.2 Withered yellow tobacco leaves, dead green tobacco leaves, moldy tobacco leaves, and forked tobacco leaves are not graded.

6.1.3 Spice grading is conducted using loose leaves or bunches, and the total amount of high-grade or low-grade tobacco leaves blended in each grade should not exceed 15% (based on quality). (Measurement).

6.1.4 The moisture content of the aromatic tobacco purchased should be controlled between 14.0% and 16.0%.

6.1.5 The natural sand content of tobacco leaves of all grades should not exceed 1.5%, and for other grades it should not exceed 1.0%.

7.1 Grade Inspection

7.1.1 The inspection of aromatic tobacco grades shall follow the principles of classification, grouping, and grading, and shall be carried out item by item using sensory inspection methods in accordance with the technical requirements in Chapter 6. Perform the inspection.

7.1.2 The testing method for the grade of aromatic smoke shall be carried out in accordance with the requirements of YC/T 635.

7.2.1 Instruments and Equipment

7.2.1.1 Analytical balance. resolution 0.001g.

7.2.1.2 Oven. Equipped with a temperature regulating device, a temperature control range of ±1°C, and a temperature detection and display device.

7.2.1.3 Glass desiccant. contains desiccant.

7.2.1.4 Aluminum sample box. 60mm in diameter and 25mm in height.

7.2.2 Operating Procedures Evenly extract the leaves to be tested from the submitted sample and quickly cut them into small pieces or shreds no wider than 5 mm. Mix thoroughly and then dry with a known dryer. Weigh approximately 5g to 10g of the sample into the sample box and record the mass. After removing the lid, place the sample in an oven at 100°C±1°C. From the moment the temperature rises back to 100°C, bake for 2 hours, cover, remove, place in a desiccator, cool to room temperature, and then weigh.

7.3.1 Instruments and Equipment

7.3.1.1 Analytical balance. resolution 0.001g.

7.3.1.2 Brush. approximately 100mm wide and 70mm long.

7.3.1.3 Separating sieve. 0.25mm aperture (equivalent to 60 mesh), with sieve cover and sieve bottom.

7.3.2 Operating Procedures Two parallel samples were taken evenly from the submitted samples, each weighing 400g to 600g. The mass of each sample was recorded, and the smoke was placed on glossy paper. Spread the leaves out, and use a brush to lightly brush each leaf on both sides at least three times. Collect the brushed-off sand and soil, and pass it through a separating sieve until no more sand can be sieved. Weigh the sieved sand and record its quality.

8 standard samples

8.1 Standard samples are prepared based on written standards and serve as one of the bases for grading and testing. The development, management, and use of standard samples are governed by the "National Standards for Standard Samples". The "Standard Sample Management Measures", "National Reference Sample Approval Measures for Tobacco Leaves (Trial)" and GB/T 15000 (all parts).

8.2 Standard samples consisted mainly of medium-quality leaves from each grade, including roughly equal numbers of better and worse leaves. Each grade... 250g~500g, pressed into sizes of (300mm×160mm×30mm)~(300mm×160mm×50mm), using non-toxic transparent... Plastic packaging.

8.3 Standard samples shall indicate the place of origin, variety, grade, and year, and shall be stamped with the seal of the approving authority.

8.4 When performing standard sample testing, the overall quality level should be used as a reference.