This standard specifies the instruments, reagents, analytical procedures and result calculations used in the determination of insoluble dietary fiber in cereals. This standard applies to the determination of insoluble dietary fiber in cereals. GB/T 9822-1988 Determination of insoluble dietary fiber in cereals GB/T9822-1988 Standard download decompression password: www.bzxz.net
This standard specifies the instruments, reagents, analytical procedures and result calculations used in the determination of insoluble dietary fiber in cereals. This standard applies to the determination of insoluble dietary fiber in cereals.
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National Standard of the People's Republic of China Method for determination of insoluble dietary fiber in cereals 1 Subject content and scope of application This standard specifies the instruments, reagents, analytical steps and result calculation used for the determination of insoluble dietary fiber in cereals. This standard is applicable to the determination of insoluble dietary fiber in cereals. 2 Principle of the method UDC 633.1 GB 9822-88 The cereal sample is soaked in a neutral detergent solution, and the residue is fully washed with hot water. Then, an amylase solution is added to decompose the residual bound starch. Then, it is washed with water and acetone and dried to obtain the insoluble dietary fiber. 3 Instruments and equipment 3.1 Extraction device: It consists of a 300mL conical flask with a condenser at the bottle mouth and an adjustable electric heating plate that can heat 100mL of water from room temperature to boiling within 5~~10min. 3.2Fs-2 glass filter crucible (filter disc No. 2, 30mL volume). 3.3Electrothermal oven. 3.4Electrothermal incubator: temperature maintained at 37±2℃. 3.5Dryer: equipped with effective desiccant. 3.6Filter device: composed of glass filter and suction filter bottle, filtered by water pump or vacuum pump. 3.7 Pulverizer. 4Reagents The reagents used in this standard are analytically pure unless otherwise specified, and the water is distilled water. 4.1Sodium dodecyl sulfate: chemically pure. Disodium ethylenediaminetetraacetate (EDTA) (GB 1401). 4.3Sodium tetraborate (GB632). Disodium hydrogen phosphate (GB1263). Ethylene glycol monoethyl ether: chemically pure. Decalin: chemically pure. Anhydrous sodium sulfite. Petroleum ether: boiling range 30~60℃. Sodium dihydrogen phosphate (GB 1267). Acetone (GB686). Www.bzxZ.net 4.11α-amylase\(enzyme activity not less than 800A per mg). Approved by the Ministry of Commerce of the People's Republic of China on July 6, 1988346 Implementation on March 1, 1989 GB9822-88 : 1) Alpha-amylase crystalline freeze-dried powder or similar products produced by the reagent factory of Shanghai Institute of Biochemistry can be used. The enzyme activity determination method is shown in Appendix A (Supplement) of GB9826 "Determination of damaged starch in wheat flour α-amylase method" Determination of α-amylase activity. 4.12 Toluene (GB684): chemically pure. 4.13 Preparation of neutral detergent solution: Disodium ethylenediaminetetraacetate 18.61 and sodium tetraborate 6.81 were heated and dissolved in 150 mL of water. 30 g of sodium dodecyl sulfate and 10 mL of ethylene glycol monoethyl ether were dissolved in 700 mL of hot water and then added to the first solution. Dissolve 4.56 g of disodium hydrogen phosphate in 150 mL of hot water and add to the first solution. If necessary, adjust the pH to 6.7 to 7.1 with phosphoric acid. If a precipitate is formed during use, heat to 60°C to dissolve the precipitate. 4.14 Preparation of α-amylase solution: Mix 500 mL of 0.1 mol/L disodium hydrogen phosphate and 0.1 mol/L sodium dihydrogen phosphate solution to make 0.1 mol/L phosphate buffer. Weigh 12.5 mg of α-amylase, dissolve it in 0.1 mol/L phosphate buffer and dilute to 250 mL. 5 Analysis steps 5.1 Sample preparation: The grain sample is ground once by a suitable grinder and all of it passes through a 1mm sieve (the sample fineness is about 20-60 mesh). 5.2 Accurately weigh 0.500-1.000g of the prepared sample and put it into a 300mL conical flask. 5.3 Add in sequence: (a) 100mL neutral detergent solution; (b) 2mL decahydrogen; (c) 0.50g anhydrous sodium sulfite. 5.4 Heat the contents of the 300mL conical flask to boiling within 5-10min, starting from boiling, and boiling slightly for 1h. 5.5 Dry the clean glass filter crucible in an oven at 110℃ for 4h, put it in a desiccator, and weigh it after cooling until constant weight. Add the fiber residue treated with neutral detergent solution, filter it, and wash it with not less than 300mL of 100℃ water. 5.6 Add 5mL of α-amylase solution, filter to replace the washing water, then plug the bottom of the glass filter crucible with a suitable rubber stopper, add 20mL of enzyme solution and a few drops of toluene. 5.7 Place in an incubator at 37±2℃ and keep warm for 18h. 5.8 Remove the stopper, filter, wash the fiber residue with no less than 500mL of water, and then wash with about 75mL of acetone. Dry in an oven at 100℃ for 4h, then place in a desiccator, weigh after cooling until constant weight. 6 Result calculation 6.1 Calculation formula: Insoluble dietary fiber (%) = m2m×100m Where: ml-—glass filter drying mass, 8m2——glass filter and residue drying mass, g; m—sample mass, 8. 7 Allowable difference The maximum allowable difference between the measured values of two parallel samples is 1.0%. The arithmetic mean value is taken as the determination result, and one decimal place is retained. Additional remarks: This standard is under the jurisdiction of the Grain Storage and Transportation Bureau of the Ministry of Commerce. This standard was drafted by the Institute of Cereal Oil Chemistry of the Ministry of Commerce. The main drafter of this standard is Pan Duo. 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.