This standard specifies the reference method for fat determination. This standard is applicable to the determination of fat in infant formula and milk powder. GB/T 5413.3-1997 Determination of fat in infant formula and milk powder GB/T5413.3-1997 Standard download decompression password: www.bzxz.net

GB/T 5413. 3-1997
This standard is equivalent to the International Dairy Federation standard IDF9C: 1987 "Milk powder, whey powder, buttermilk powder and whey powder - Determination of fat content - Rozs-Gottlieb gravimetric analysis (reference method)". This method has high accuracy and is the reference method for determining the fat content in milk, milk powder and infant formula.
This series of standards will replace GB5413-85 from the date of implementation. This standard is proposed by the China Light Industry Federation.
This standard is under the jurisdiction of the National Dairy Standardization Center. The responsible drafting unit of this standard: National Dairy Product Quality Supervision and Inspection Center. Participating drafting units of this standard: Food Hygiene Supervision and Inspection Institute of the Ministry of Health, Zhejiang Light Industry Research Institute, Harbin Morinaga Dairy Co., Ltd., Nestle (China) Investment Service Co., Ltd. The main drafters of this standard: Wang Yun, Huang Min, Zhang Tianshu. 228
National Standard of the People's Republic of China
Infant formula and milk powder
Determination of fat
Milk powder and formula foods for infant and young children-Determination of fat
1 Scope
This standard specifies the reference method for the determination of fat. This standard applies to the determination of fat in infant formula and milk powder. 2 Summary of method
GB/T5413.3—1997
Replaces GB 5413-85
Extract the ethanol ammonia solution of the sample with ether and petroleum ether, remove the solvent by distillation or evaporation, and determine the mass of the extract dissolved in ether.
3 Reagents
All reagents, if the specifications are not specified, are analytically pure. All experimental water, if no other requirements are specified, refers to grade tertiary water. Carry out a blank test according to the steps specified in 5.3 to check the purity of the reagents. Prepare an empty fat collection bottle according to the operation of 5.4 to correct for environmental effects. The content of reagent residues shall not exceed 0.5 mg (see 8.1). If the total reagent blank residue is greater than 0.5 mg, distill 100 mL of ether and petroleum ether respectively and determine the content of solvent residues. The amount measured with the empty control bottle and the content of each solvent residue should not exceed 0.5 mg. Replace the unqualified reagents or purify the reagents. 3.1 Amylase.
3.2 Ammonia solution: mass fraction of about 25%, P20 of about 910g/L. Note: If this concentration of ammonia solution is not available, a known, higher concentration of ammonia solution can be used (see 5.5.2). 3.3 Ethanol or ethanol denatured by methanol: volume fraction of at least 94% (see 8.5). 3.4 Congo red solution 1g Congo red is dissolved in water and diluted to 100mL. Note: It can be used selectively. Congo red solution can make the interface between solvent and water phase clear (see 5.5.4). Other solutions that can dye the water phase without affecting the test results can also be used.
3.5 Ether: does not contain peroxide (see 8.3), does not contain antioxidants, or the antioxidant content is not more than 2 mg/kg, and meets the requirements of blank test (see Chapter 3, 8.1 and 8.4).
3.6 Petroleum ether: boiling range 30～60℃.
3.7 Mixed solvent: mix ether (3.5) and petroleum ether (3.6) in equal volumes and prepare before use. 4 Instruments
Since volatile flammable solvents are used in the determination, the use of all electrical appliances should be carried out in accordance with the relevant regulations on the use of these solvents. Common laboratory instruments and:
Approved by the State Administration of Technical Supervision on May 28, 1997 and implemented on September 1, 1998
4.1 Analytical balance.
GB/T5413.3--1997
4.2 Centrifuge: can hold liposuction bottle or tube (4.6), with a rotation speed of 500-600r/min, and can generate a gravity field of 80-90g at the outer end of the liposuction bottle.
Note: optional.
4.3 Distiller or evaporator: can be used to distill away the solvent and ethanol in the fat collection bottle, or evaporate the solvent and ethanol in the beaker or flat blood without exceeding 100℃ (see 5.5.10, 5.5.14). 4.4 Oven: electric heating, with the vent fully open, the working area temperature can be controlled at 102℃±2C. Equipped with an appropriate thermometer. 4.5 Water bath: the temperature can be controlled at 65℃±5℃. 4.6 Mao's liposuction bottle: The liposuction bottle (or tube, see note) should be equipped with a suitable high-quality cork or other bottle stopper that does not affect the use of solvents (such as silicone or polytetrafluoroethylene). The cork should be first soaked in ether (3.5), then placed in water at 60°C or above for at least 15 minutes, and then cooled in water. The cork is saturated when used. It should be soaked in water when not in use, and the soaking water should be changed once a day. Note: Liposuction tubes (or flasks) with siphons or wash bottles can also be used, but the operating procedures are different, as specified in Appendix A. The lower end of the internal long branch of the joint can be spoon-shaped.
4.7 Stand: Place the liposuction bottle (or tube). 4.8 Wash bottle: Suitable for holding mixed solvents (3.7). Plastic wash bottles cannot be used. 4.9 Fat collection bottle: For example: a heatable flask (flat-bottom flask) with a capacity of 125 to 250 mL, a 250 mL conical flask or a metal blood. If metal III is used, it is best to use stainless steel, flat bottom, overflow port, diameter 80-100mm, height about 50mm. 4.10 Zeolite: fat-free, non-porous porcelain or silicon carbide or glass beads (in case of metal III). 4.11 Measuring cylinder: 5mL and 25mL.
4.12 Pipette: graduated, 10mL. 4.13
Metal clamp: used to clamp flasks, beakers or dishes. 4.14 Mao's liposuction bottle shaker: can clamp Mao's liposuction bottle, swing frequency is 100±10 times/min. 5 Operation steps
5.1 Sample preparation
Repeatedly rotate the sample container to mix the sample thoroughly (if necessary, transfer all the experimental samples into a large closed container before performing this operation).
5.2 Sample Portion
Gently stir or swirl the sample container to mix the test sample (5.1). Immediately remove a sample and place it directly in a liposuction bottle (4.6) or other container, accurate to 1 mg, and the sample volume is as follows:
a) High fat milk powder, whole milk powder, whole fat sweetened milk powder and formula milk powder: about 1 g. b) Partially skimmed milk powder: about 1.5 g.
c) Skimmed milk powder: about 1.5 g.
d) Whey powder: about 1.5 g.
e) Buttermilk powder: about 1.5 g.
f) Milk-containing infant cereal (formula): about 1.5 g. 5.3 Blank Test
The blank test is carried out at the same time as the sample test, using the same procedures and the same reagents, but using 10 mL of water (see 8.2) instead of the diluted sample (5.5.1).
5.4 Preparation of fat collection bottle
Add a few grains of zeolite (4.10) to the dry collection bottle (4.9) and place in an oven (4.4) to dry for 1 hour. Allow the collection bottle to cool (dust-proof) to the temperature of the balance room (at least 1 hour for glass collection bottles and at least 0.5 hours for metal III). 230
GB/T 5413. 3-1997
1 During the solvent removal process, especially when using glass collection bottles, zeolite can make the boiling uniform. When using metal blood, zeolite can also be used as an option. 2 The collection bottle should not be placed in a desiccator to avoid insufficient cooling or excessive cooling time. Use clamps (4.13) (to avoid temperature changes) to place the collection bottle on the balance and weigh it to the nearest 0.1 mg. 5.5 Determination
5.5.1 Sample treatment
5.5.1.1 Starch-free sample
Add 10mL of 65℃±5℃ water, wash the sample into the small ball of the liposuction bottle, mix thoroughly until the sample is completely dispersed, and cool it in running water.
5.5.1.2 Starch-containing sample
Put the sample in a Mao's liposuction bottle, add about 0.1g of amylase and a small magnetic stirring bar, mix well, and then add 8-10mL of 45℃ distilled water. Be careful not to let the liquid level be too high. Cover the bottle with a stopper and place it in a 65℃ water bath for 2h while stirring. Shake it every 10min. Check whether the starch is completely hydrolyzed: add two drops of about 0.1mol/L iodine solution. If no blue color appears, the hydrolysis is complete. Otherwise, put the liposuction bottle back in the water bath until no blue color is produced. Cool the Mao's liposuction bottle.
5.5.2 Add 2 mL of ammonia solution (3.2) or the same volume of concentrated ammonia solution (see note 3.2) and mix thoroughly with the dissolved sample in the pellet. After adding ammonia solution, proceed to the next step immediately. 5.5.3 Place the liposuction bottle in a water bath at 65°C ± 5°C (4.5), heat for 15-20 minutes, shake occasionally, remove, and cool to room temperature. Starch-containing samples do not need a water bath, and the following steps can be performed after standing for 30 seconds. 5.5.4 Add 10 mL of ethanol (3.3), gently allow the contents to flow back and forth between the small ball and the column, mix gently but thoroughly, and avoid the liquid getting too close to the bottleneck. If necessary, add 2 drops of Congo red solution (3.4). 5.5.5 Add 25 mL of ether (3.5), plug with a water-saturated cork (see 4.6), or other bottle stoppers wet with water, keep the liposuction bottle in a horizontal position, clamp the extension of the small ball to the shaker with the ball facing up, and shake the flask at about 100 times/min for 1 minute. Do not over-shake (to avoid the formation of a persistent emulsion). During this period, allow the liquid to flow from the large ball into the small ball. If necessary, cool the liposuction bottle in running water, then carefully open the stopper and rinse the stopper and bottleneck with a small amount of mixed solvent (3.7) [use a washing bottle (4.8) for rinsing], and let the rinsing liquid flow into the liposuction bottle or the prepared fat collection bottle (see 5.4). 5.5.6 Add 25mL of petroleum ether (3.6), plug the re-moistened stopper (immerse in water), and continue as described in 5.5.5, gently shake for 30 seconds. 5.5.7 Place the stoppered liposuction bottle in a centrifuge (4.2) and centrifuge at 500~～600r/min for 1～5 minutes. If there is no centrifuge, place the liposuction bottle on a stand (4.7) and let it stand for at least 30 minutes until the upper liquid is clear and clearly separated from the water phase. If necessary, cool the liposuction bottle in running water.
5.5.8 Carefully open the soft stopper or bottle stopper, and rinse the stopper and the inner wall of the bottleneck with a small amount of mixed solvent, so that the rinse liquid flows into the liposuction bottle or fat collection bottle.
If the interface between the two phases is lower than the junction of the ball and the bottle body, slowly add water along the edge of the bottle wall to make the liquid level higher than the junction of the ball and the bottle body (see Figure 1) for easy pouring.
5.5.9 Hold the ball part of the liposuction bottle and carefully pour as much of the upper layer of liquid as possible into the prepared fat collection bottle containing zeolite (metal square meter can also be used), avoiding pouring out the water layer (see Figure 2). 231
After the second and third extractions
After the first extraction
Figure 1 Before pouring out the ether layer
(5.5.8,5.5.12,5.5.13)
GB/T5413.3—1997
After the second and third extractions
After the first extraction
Figure 2 After pouring out the ether layer
(5.5.9,5.5.12,5.5.13)
5.5.10 Rinse the outside of the bottleneck with a small amount of mixed solvent and collect the rinse in the fat collection bottle. Be careful to prevent the solvent from splashing onto the outside of the liposuction bottle.
It is best to remove part of the solvent in the fat collection bottle by distillation or evaporation as described in 5.5.14. 5.5.11 Add 5 mL of ethanol (3.3) to the liposuction bottle, rinse the inner wall of the bottleneck with ethanol, and mix as described in 5.5.4. 5.5.12 Repeat the steps 5.5.5 to 5.5.10 for the second extraction, but use only 15 mL of ether (3.5) and 15 mL of petroleum ether (3.6), and rinse the inner wall of the bottleneck with the mixed solvent (3.7). 5.5.13 Repeat the steps 5.5.5 to 5.5.9 for the third extraction, but use only 15 mL of ether (3.5) and 15 mL of petroleum ether (3.6), and rinse the inner wall of the bottleneck with the mixed solvent (3.7). Note: If the mass fraction of fat in the product is less than 5%, the third extraction can be omitted. 5.5.14 Remove the solvent (including ethanol) from the collection bottle by distillation. For beakers or blood, use evaporation (4.3) to remove the solvent. Rinse the inside of the bottleneck with a small amount of mixed solvent (3.7) before distillation. 5.5.15 Place the fat collection bottle in an oven (4.4) at 102℃ ± 2℃ for 1 hour, remove the collection bottle, and cool it to the temperature of the balance room (do not place it in a desiccator, but keep it dust-proof. Cool the glass container for at least 1 hour and the metal container for at least 0.5 hour). Weigh it to the nearest 0.1 mg. Do not wipe the collection bottle before weighing. Place the collection bottle on the balance with a clamp (to avoid temperature changes). 5.5.16 Repeat the operation in 5.5.15 until the fat collection bottle weighs no more than 0.5 mg twice in a row. Record the lowest mass of the collection bottle and the extract.
5.5.17 To verify whether the extract is completely dissolved, add 25 mL of petroleum ether to the fat collection bottle, heat it slightly, and shake it until the fat is completely dissolved.
If the extract is completely dissolved in the petroleum ether, the difference between the final mass of the collection bottle containing the extract (see 5.5.16) and the initial mass (see 5.4) is the fat content.
5.5.18 If the extract is not completely dissolved in petroleum ether, or if it is doubtful whether the extract is entirely fat, use hot petroleum ether to elute. Allow a trace of insoluble matter to precipitate. Carefully pour out the petroleum ether without pouring out any insoluble matter. Repeat this operation for more than 3 times, and then rinse the inside of the mouth of the collection bottle with petroleum ether.
Finally, rinse the outside of the mouth of the collection bottle with the mixed solvent to avoid splashing the solution onto the outer wall of the bottle. Place the fat collection bottle in an oven (4.4) at 102°C ± 2°C for 1 hour, remove the petroleum ether as described in 5.5.15 and 5.5.16, cool, and weigh. Take the difference between the mass measured in 5.5.16 and the mass measured in 5.5.18 as the mass of fat. Note: When selecting a liposuction tube with a siphon or bottle washing attachment (see note 4.6), the steps are as described in Appendix A (Standard Appendix). 6 Expression of analysis results
Fat content in sample (g/100g) (ml = m) = (msm2 × 100mo
(1)
Where: mo
Mass of sample (5.2), g;
GB/T 5413.3—1997
The mass of the fat collection bottle and the extract measured in 5.5.16, g, the mass of the fat collection bottle (5.4), or in the presence of insoluble matter, the mass of the fat collection bottle and the insoluble matter measured in 5.5.18, g,
In the blank test (5.3), the mass of the fat collection bottle and the extract measured in 5.5.16, g The mass of the fat collection bottle (see 5.4) in the blank test (5.3), or in the presence of insoluble matter, the mass of the fat collection bottle and the insoluble matter measured in 5.5.18, g.
Report the mass fraction result to the nearest 0.01%. 7 Allowable difference
7. 1 Repeatability
The difference between the results of two separate tests on the same sample made by the same analyst within a short time interval should not exceed the following values: High-fat milk powder, whole milk powder, whole fat sweetened milk powder and formula milk powder Partially skimmed milk powder, buttermilk powder
-skimmed milk powder
Whey powder
Milk-containing infant cereal (formula) food
7.2 Reproducibility
0.2g fat/100g sample
0.15g fat/10 0g sample
0.1g fat/100g sample
0.1g fat/100g sample
0.2g fat/100g sample
The difference between two independent test results of the same sample made by two analysts from different laboratories should not exceed the following values: - high-fat milk powder, whole milk powder, whole fat sweetened milk powder and formula milk powder 0.3g fat/100g sample
partial skim milk powder, buttermilk powder
- skim milk powder
Whey powder
Infant cereal (formula) food containing milk
8 Precautions during the experiment
8.1 Blank test reagents
0.25g fat/100g sample
0.2g fat/100g sample
0.2g fat/100g sample
0.45g fat/100g sample
When performing the blank test, use a quality control bottle to eliminate the influence of environmental and temperature. The influence of temperature on the test results. In extremely rare cases, there may be volatile substances that are easily soluble in fat in the solvent. In this case, a blank test should be performed on all reagents. When performing a blank test, place 1g of fresh anhydrous butter in the fat collection bottle. If necessary, add 1g of anhydrous butter to every 100ml of solvent and redistill it. It must be used as soon as possible after redistillation. 8.2 The blank test is carried out simultaneously with the sample determination. For reagents containing non-volatile substances, the blank test value carried out simultaneously with the sample determination can be used for correction. The temperature difference between the liposuction bottle and the balance room can affect the quality of the extract ((5.5.16 and 5.4 or 5.5.18). Under ideal conditions (low reagent blank value, the same balance room temperature, and the fat collection bottle is fully cooled), this value is usually less than 0.5mg. In routine determination, it can be ignored. If this value is slightly higher (±2.5mg), can generally be ignored, and the result is still accurate after correction. However, when the correction value is greater than 2.5mg, this should be stated in the test report.
If the blank test value often exceeds 0.5mg and the reagent has not been tested recently, the reagent should be tested immediately and any impure reagents should be replaced or purified (Chapter 3 and 8.1). 8.3 Test for peroxides in ether
Take a small measuring cylinder with a glass stopper, rinse it with ether, then add 10mL of ether, then add 1mL of freshly prepared 100g/L potassium iodide solvent, shake, let it stand for 1min, and there should be no yellow in both phases. Other appropriate methods can also be used to test peroxides. 233
GB/T5413.3-1997
In order to ensure that there is no peroxide in the ether for a long time without adding antioxidants, the following method should be used for the first three days of use: cut the zinc foil into strips, the length of which is at least half of the ether bottle, and use 80cm2 of zinc foil for each liter of ether. Before use, completely immerse the zinc sheet in a solution containing 10g of copper sulfate pentahydrate and 2mL of 98% concentrated sulfuric acid per liter for 1min, rinse the zinc sheet gently and thoroughly with water, and put the wet copper-plated zinc sheet into the ether bottle. Other methods can also be used, but they must not affect the test results.
8.4 The situation of antioxidants in ether
If there is about 1mg of antioxidants in every 1kg of ether, it will not affect the use. If the ether contains a high content of antioxidants, for example, 7 mg antioxidants per kilogram, this ether is only used for routine determination, and the blank test and sample determination should be carried out simultaneously to correct the systematic error caused by the antioxidant residue. If used for reference method determination, it should be redistilled before use. 8.5 Ethanol
Non-methanol denatured ethanol can also be used as long as it does not affect the determination results. 234
GB/T 5413.3-1997
Appendix A
(Standard Appendix)
Procedure for using a liposuction tube with a siphon or a wash bottle If a liposuction tube with a siphon or a wash bottle is used (see Note 4.6), the steps are as follows. A1 Steps
A1.1 Sample preparation: See 5.1.
A1.2 Sample part
Handling process as described in 5.2, but use a liposuction tube (4.6). The sample should be transferred to the bottom of the liposuction tube as quickly as possible. A1.3 Blank test: see 5.3 and 8.2.
A7.4 Preparation of fat collection bottle: see 5.4. A1.5 Determination
A1.5.1 Sample treatment
A7.5.1.1 Add 10mL of 65℃±5℃ water to the sample, wash the sample into the bottom of the liposuction tube, and mix thoroughly. Continue with step A1.5.2.
A1.5.1.2 See 5.5.1.2.
A1.5.2 Add 2mL of ammonia solution (3.2) or an equal volume of ammonia solution (3.2 Note), and mix thoroughly with the diluted sample at the bottom of the tube. After adding ammonia water, proceed to the next step immediately.
A1.5.3 Place the liposuction tube in a 65℃±5℃ water bath (4.5), heat for 15 to 20 minutes, shake the sample tube occasionally, and then cool to room temperature.
A1.5.4 Add 10 mL of ethanol (3.3) and mix gently and thoroughly at the bottom of the tube. If necessary, add 2 drops of Congo red solution (3.4). A7.5.5 Add 25 mL of ether (3.5), add a cork (saturated with water), or other bottle stopper soaked in water, and invert for 1 min. Do not overdo it (to avoid the formation of a persistent emulsion). If necessary, place the tube in running water to cool, then carefully open the cork and rinse the stopper and tube neck with a small amount of mixed solvent (3.7) (using a wash bottle) (4.8), allowing the rinse solution to flow into the tube. A1.5.6 Add 25 mL of petroleum ether (3.6), stopper (re-wet the stopper with water), and gently shake for 30 s as described in A1.5.4. A1.5.7 Place the stoppered tube in a centrifuge and centrifuge at 500~~600 r/min (3.2) for 1~5 min. If a centrifuge is not available, place the tube on a stand (4.7) and let it sit for at least 30 minutes until the upper liquid is clear and clearly separated from the aqueous phase. If necessary, cool the tube in running water.
A1.5.8 Carefully open the cork and wash the cork and tube neck with a small amount of mixed solvent, allowing the flushing liquid to flow into the tube. A1.5.9 Insert a siphon or bottle wash connector into the tube and press the long branch down until it is 4 mm above the two-phase interface. The internal long branch should be parallel to the tube axis.
Carefully transfer the upper liquid into a collection bottle containing zeolite (4.10). Metal III can also be used. Avoid transferring any aqueous phase. Rinse the outlet of the long branch with a small amount of mixed solvent and collect the flushing liquid in the collection bottle. A1.5.10 Loosen the connector at the neck of the tube, rinse the connector and the lower part of the internal long branch with a small amount of mixed solvent, re-insert the connector, and transfer the flushing liquid into the collection bottle.
Rinse the outlet with a small amount of mixed solvent and collect the rinse liquid in a bottle. If necessary, remove part of the solvent by distillation or evaporation as described in 5.5.14.
A1.5.11 Loosen the joint at the neck of the tube again, raise the joint slightly, add 5mL of ethanol, and rinse the long branch with ethanol. Mix as described in A1.5.4.
A1.5.12 Repeat steps A1.5.5 to A1.5.10 for the second extraction, but only use 15mL (3.5) ethanol and 15mL petroleum ether. After extraction, rinse the internal long branch with ether while removing the tube joint. A1.5.13 Repeat steps A1.5.5 to A1.5.10 without adding ethanol, and perform the third extraction, using only 15 mL (3.5) ethanol and 15 mL petroleum ether.
Note: If the mass fraction of fat in the product is less than 5%, the third extraction can be omitted. A1.5.14 The following shall be carried out in accordance with 5.5.14 to 5.5.18. Unit: mm
Outer diameter 4±0.4
Outer diameter 4±0.4
Capacity 105mL±5ml
002
a) Liposuction tube with siphon
Wall thickness 1.5±0.5
Inner diameter $26±1
Inner diameter 6±1
Liposuction tube legend
002
b) Liposuction tube with wash bottle5 Determination
A1.5.1 Sample treatment
A7.5.1.1 Add 10 mL of 65℃±5℃ water to the sample, wash the sample into the bottom of the liposuction tube, and mix thoroughly. Continue with step A1.5.2.
A1.5.1.2 See 5.5.1.2.
A1.5.2 Add 2 mL of ammonia solution (3.2) or an equal volume of ammonia solution (3.2 Note), and mix thoroughly with the diluted sample at the bottom of the tube. After adding ammonia water, proceed to the next step immediately.
A1.5.3 Place the liposuction tube in a 65℃±5℃ water bath (4.5), heat for 15 to 20 minutes, shake the sample tube occasionally, and then cool to room temperature.
A1.5.4 Add 10 mL of ethanol (3.3), mix gently and thoroughly at the bottom of the tube, and add 2 drops of Congo red solution (3.4) if necessary. A7.5.5 Add 25 mL of ether (3.5), add a cork (saturated with water), or other bottle stopper soaked in water, and invert for 1 min. Do not overdo it (to avoid the formation of a persistent emulsion). If necessary, place the tube in running water to cool, then carefully open the cork and rinse the stopper and tube neck with a small amount of mixed solvent (3.7) (using a washing bottle) (4.8), allowing the rinse solution to flow into the tube. A1.5.6 Add 25 mL of petroleum ether (3.6), stopper (re-wet the stopper with water), and gently shake for 30 s as described in A1.5.4. A1.5.7 Place the stoppered tube in a centrifuge and centrifuge at 500~~600 r/min (3.2) for 1~5 min. If a centrifuge is not available, place the tube on a stand (4.7) and let it sit for at least 30 minutes until the upper liquid is clear and clearly separated from the aqueous phase. If necessary, cool the tube in running water.
A1.5.8 Carefully open the cork and wash the cork and tube neck with a small amount of mixed solvent, allowing the flushing liquid to flow into the tube. A1.5.9 Insert a siphon or bottle wash connector into the tube and press the long branch down until it is 4 mm above the two-phase interface. The internal long branch should be parallel to the tube axis.
Carefully transfer the upper liquid into a collection bottle containing zeolite (4.10). Metal III can also be used. Avoid transferring any aqueous phase. Rinse the outlet of the long branch with a small amount of mixed solvent and collect the flushing liquid in the collection bottle. A1.5.10 Loosen the connector at the neck of the tube, rinse the connector and the lower part of the internal long branch with a small amount of mixed solvent, re-insert the connector, and transfer the flushing liquid into the collection bottle.
Rinse the outlet with a small amount of mixed solvent and collect the rinse liquid in a bottle. If necessary, remove part of the solvent by distillation or evaporation as described in 5.5.14.
A1.5.11 Loosen the joint at the neck of the tube again, raise the joint slightly, add 5mL of ethanol, and rinse the long branch with ethanol. Mix as described in A1.5.4.
A1.5.12 Repeat steps A1.5.5 to A1.5.10 for the second extraction, but only use 15mL (3.5) ethanol and 15mL petroleum ether. After extraction, rinse the internal long branch with ether while removing the tube joint. A1.5.13 Repeat steps A1.5.5 to A1.5.10 without adding ethanol, and perform the third extraction, using only 15 mL (3.5) ethanol and 15 mL petroleum ether.
Note: If the mass fraction of fat in the product is less than 5%, the third extraction can be omitted. A1.5.14 The following shall be carried out in accordance with 5.5.14 to 5.5.18. Unit: mm
Outer diameter 4±0.4
Outer diameter 4±0.4
Capacity 105mL±5ml
002
a) Liposuction tube with siphon
Wall thickness 1.5±0.5
Inner diameter $26±1
Inner diameter 6±1
Liposuction tube legend
002
b) Liposuction tube with wash bottle5 Determination
A1.5.1 Sample treatment
A7.5.1.1 Add 10 mL of 65℃±5℃ water to the sample, wash the sample into the bottom of the liposuction tube, and mix thoroughly. Continue with step A1.5.2.
A1.5.1.2 See 5.5.1.2.
A1.5.2 Add 2 mL of ammonia solution (3.2) or an equal volume of ammonia solution (3.2 Note), and mix thoroughly with the diluted sample at the bottom of the tube. After adding ammonia water, proceed to the next step immediately.
A1.5.3 Place the liposuction tube in a 65℃±5℃ water bath (4.5), heat for 15 to 20 minutes, shake the sample tube occasionally, and then cool to room temperature.
A1.5.4 Add 10 mL of ethanol (3.3), mix gently and thoroughly at the bottom of the tube, and add 2 drops of Congo red solution (3.4) if necessary. A7.5.5 Add 25 mL of ether (3.5), add a cork (saturated with water), or other bottle stopper soaked in water, and invert for 1 min. Do not overdo it (to avoid the formation of a persistent emulsion). If necessary, place the tube in running water to cool, then carefully open the cork and rinse the stopper and tube neck with a small amount of mixed solvent (3.7) (using a washing bottle) (4.8), allowing the rinse solution to flow into the tube. A1.5.6 Add 25 mL of petroleum ether (3.6), stopper (re-wet the stopper with water), and gently shake for 30 s as described in A1.5.4. A1.5.7 Place the stoppered tube in a centrifuge and centrifuge at 500~~600 r/min (3.2) for 1~5 min. If a centrifuge is not available, place the tube on a stand (4.7) and let it sit for at least 30 minutes until the upper liquid is clear and clearly separated from the aqueous phase. If necessary, cool the tube in running water.
A1.5.8 Carefully open the cork and wash the cork and tube neck with a small amount of mixed solvent, allowing the flushing liquid to flow into the tube. A1.5.9 Insert a siphon or bottle wash connector into the tube and press the long branch down until it is 4 mm above the two-phase interface. The internal long branch should be parallel to the tube axis.
Carefully transfer the upper liquid into a collection bottle containing zeolite (4.10). Metal III can also be used. Avoid transferring any aqueous phase. Rinse the outlet of the long branch with a small amount of mixed solvent and collect the flushing liquid in the collection bottle. A1.5.10 Loosen the connector at the neck of the tube, rinse the connector and the lower part of the internal long branch with a small amount of mixed solvent, re-insert the connector, and transfer the flushing liquid into the collection bottle. www.bzxz.net
Rinse the outlet with a small amount of mixed solvent and collect the rinse liquid in a bottle. If necessary, remove part of the solvent by distillation or evaporation as described in 5.5.14.
A1.5.11 Loosen the joint at the neck of the tube again, raise the joint slightly, add 5mL of ethanol, and rinse the long branch with ethanol. Mix as described in A1.5.4.
A1.5.12 Repeat steps A1.5.5 to A1.5.10 for the second extraction, but only use 15mL (3.5) ethanol and 15mL petroleum ether. After extraction, rinse the internal long branch with ether while removing the tube joint. A1.5.13 Repeat steps A1.5.5 to A1.5.10 without adding ethanol, and perform the third extraction, using only 15 mL (3.5) ethanol and 15 mL petroleum ether.
Note: If the mass fraction of fat in the product is less than 5%, the third extraction can be omitted. A1.5.14 The following shall be carried out in accordance with 5.5.14 to 5.5.18. Unit: mm
Outer diameter 4±0.4
Outer diameter 4±0.4
Capacity 105mL±5ml
002
a) Liposuction tube with siphon
Wall thickness 1.5±0.5
Inner diameter $26±1
Inner diameter 6±1
Liposuction tube legend
002
b) Liposuction tube with wash bottle
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.