[PDF] GB/T 14698-2017 - Auto immediate delivery.
Drafting Organization: National Feed Quality Supervision and Inspection Center (Wuhan), New Hope VI and Co., Ltd., Guangzhou Kang Ruide Biotechnology Co., Ltd., Hunan Zhenghong Technology Development Co., Ltd.
Technical changes are as follows.
--- Increased petroleum ether degreasing treatment (see 7.2.3).
Technology Co., Ltd., Hunan Zhenghong Technology Development Co., Ltd.
The main drafters of this standard. Yang Haipeng, Guo Jiyuan, Liu Xianrong, Yang Lin, Rong Jia, Zhu Zhengpeng, Hu Zhenjun, Wang Hu, Qian Ying, Jiang Xiaoxia.
--- GB/T 14698-1993, GB/T 14698-2002.
This standard specifies the method of microscopic examination of feed ingredients.
This standard applies to feed qualitative qualitative examination of the microscope.
2017, to identify and evaluate its type and quality.
4.1 body microscope can zoom 7 times to 40 times.
4.2 biological microscope. Magnification can be 40 to 500 times.
4.4 Standard sieve Aperture 0.42mm, 0.25mm, 0.177mm sieve and chassis.
4.6 drip board black and white.
4.7 Petri dishes, slides, coverslips.
4.8 pointed tweezers, pointed probes and so on.
4.9 electric oven, electric furnace, alcohol lamp and laboratory equipment commonly used.
Unless otherwise indicated, the reagents used in this standard are of analytical grade, water for the three water GB/T 6682 regulations.
5.2 Petroleum ether. Boiling point 30 ℃ ~ 60 ℃.
5.3 Acetone solution (3 1) .3 volumes of acetone are mixed with 1 volume of water.
5.4 Hydrochloric acid solution (1 1). One volume of hydrochloric acid is mixed with 1 volume of water.
5.5 Sulfuric acid solution (1 1) .1 Volume sulfuric acid is mixed with 1 volume of water.
5.6 Nitric acid solution (1 2.5) .1 Volume Nitric acid is mixed with 2.5 volumes of water.
5.7 iodine solution Weigh 0.75g potassium iodide and 0.1g iodine dissolved in 30mL water, stored in a brown bottle.
5.8 ninhydrin solution 5g/L. Weigh 0.5g ninhydrin dissolved in 100mL of water, stored in a brown bottle, is now available.
5.9 Ammonium nitrate solution .10g Ferric nitrate was dissolved in 100mL of water.
(5.6), slightly soluble, cooled and mixed with 100 mL of ammonium nitrate solution (5.9).
5.11 Suspension I. Weigh 10g chloral hydrate dissolved in 10mL water, add 10mL glycerin, mix, stored in a brown bottle.
5.12 Suspension II Weigh 160g chloral hydrate dissolved in 100mL of water, and 10mL hydrochloric acid solution (5.4).
5.13 silver nitrate solution Weigh 10g silver nitrate in 100mL water.
5.14 phloroglucinol solution 20g/L. Weigh 2g phloroglucinol dissolved in 100mL95% ethanol, placed in a brown bottle.
Follow the characterization in Feed Ingredients Catalog to collect and prepare reference samples.
Collecting rice hull flour, sawdust, peanut hull flour, leather powder, etc. may be used to serve as a dopant or adulterant sample.
Collect weed seeds often mixed with cereals.
Store at room temperature in a glass stopper or sealed sample bag.
Diameter 0.42mm sieve. Based on the characteristics of the ground feed sample, it is processed in accordance with 7.2.3, 7.2.4 and 7.2.5.
The sample is placed in a Petri dish (4.7) to be tested.
WARNING --- This procedure must be operated in a ventilated environment or fume hood, beware of explosion and fire.
Ketone solution (5.3) was repeatedly washed, sedimented and decanted twice. Slightly set back to 60 ℃ oven 20min, taken out at room temperature and cooled.
WARNING This procedure is to be carried out in a ventilated environment or in a fume hood and care should be taken to prevent organic solvents from poisoning.
10min ~ 20min, remove the sample after cooling to room temperature Petri dish (4.7) to be seized. If necessary, floating debris, sediment screening.
Twist samples feel the hardness of the size and whether it contains debris.
If necessary, compare with the same sample under the same conditions. Suspicious objects can be magnified with a magnifying glass (4.3).
(To pay attention to the comparison with the same sample under the same light source), with the lamp into the light and the sample plane to 45 ° angle as well.
Black liner. Check a sample can be used to look at the white liner again, and then look at the black liner.
Check the coarse particles look at the first look at fine particles. Use a lower magnification first, then a higher magnification.
Observe with sharp tweezers toggle, flip, and use the probe to probe the sample particles. Systematic examination of each component in the Petri dish.
Cheng in the same sample under the same conditions, compared with the test sample was observed, or with reference to GB/T 34269 comparative observation.
Do not pay attention to harmful substances.
(4.2) under the observation, the first search in the lower magnification microscope observation, and then further increase the magnification of each target observation. Compare with the reference sample.
Add about 5mL suspension Ⅱ (5.12), boil 1min, cooled, take 1 to 2 drops of the bottom sediment slide (4.7), cover glass microscopy.
The shell is generally easy to identify. The salt is usually cubic; the calcite in limestone is rhombohedral.
Identification test can be observed with the naked eye or body type microscope.
Take 2 to 5 particles of unknown suspicious material and place on drip board (4.6). Add 2 drops of silver nitrate solution (5.13) to observe the phenomenon.
--- If the particles slowly darken, indicating that unknown particles are bone.
Placed in 50mL beaker 5mL hydrochloric acid solution (5.4), observe the phenomenon.
--- The sample should also be molybdate test (9.2.4) and sulfuric acid test (9.2.5) if it is blistering or not blistering.
There is this reaction, but dihydrogen phosphate and hydrogen phosphate di-salt can be identified with silver nitrate).