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1、International Standard INTERNATIONAL ORGANIZATION FOR STANDARDlZATlON.ME)I(YHAPOJ.lHAR OPrAHM3AlWlR fl0 CTAHAAPTM3ALWlORGANlSATlON INTERNATIONALE DE NORMALISATION Decorticated stone pine nuts - Specification Pignons dbcortiquhs - Sp b) name and address of the manufacturer or packer; c) batch or code
2、 number; d) net mass (or gross mass, at the request of the importing country) ; e) producing country; f) any other marking required by the purchaser. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for
3、 Resale, 04/26/2007 22:13:58 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 67564984 (El Annex A Determination of contents of spoiled, shrivelled, broken kernels, pieces of kernels and kernels of different type or origin, and extraneous matter content A.1 Procedure Wei
4、gh, to the nearest 0,Ol g, a test portion of about 100 g. Ex- amine the test portion visually and carefully separate the spoil- ed, shrivelled, broken kernels and the kernels of different type and origin, and extraneous matter, by hand or using tweezers. Weigh each of the categories separately, to t
5、he nearest 0,Ol g. A.2 Expression of results The respective content of each category, percentage by mass, is equal to ml - x 100 m0 where m0 ml expressed as a is the mass, in grams, of the test portion; is the mass, in grams, of the category concerned. Copyright International Organization for Standa
6、rdization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/26/2007 22:13:58 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 6756-1984 (El Annex B Determination of moisture content (Entrainment method) B.1 Principle
7、 Entrainment of the water present in a test portion, by azeotropic distillation with the aid of an organic liquid not miscible with water, and measurement of the volume of water collected. B.2 Reagents / All reagents shall be of recognized analytical grade. The water used shall be distilled water or
8、 water of at least equivalent purity. B.2.1 Toluene or xylene, saturated by shaking with a small quantity of water, and distilled. Use the distillate for the determination. B.2.2 Cleaning solution : potassium dichromate-sulfuric acid solution. Dissolve 50 g of potassium dichromate in 50 ml of water
9、and add, slowly and while stirring, 400 ml of sulfuric acid, 20 = 1,84 g/ml. B.3 Apparatus Usual laboratory equipment, and in particular B.3.1 Distillation apparatus, comprising the following components fitted together by means of ground glass joints. B.3.1.1 Flask, short-necked, of capacity at leas
10、t 300 ml. 8.3.1.2 Reflux condenser, at least 50 cm long. 8.3.1.3 Receiver, with a tube of capacity 4 to 5 ml, graduated in 0,l ml divisions, interposed between the flask and the condenser. B.3.2 Mortar and pestle, permitting the kernels to be crushed without generating heat. B.3.3 Analytical balance
11、. B.4 Procedure B-4.1 Preparation of apparatus Clean the entire apparatus with the cleaning solution (8.2.2) to minimize the adherence of water droplets to the sides of the 4 condenser and receiver completely before use. . Rinse thoroughly with water and dry B.4.2 Preparation of the test sample Weig
12、h approximately 60 to 70 g from the laboratory sample, and crush the kernels in the mortar (B.3.2) within 1 min, so that the greatest dimension of the particles does not exceed 3 mm, avoiding the formation of a paste. B.4.3 Test portion Weigh, to the nearest 0,Ol g, about 50 g of the test sample (B.
13、4.21, such that the quantity of water collected will not exceed 4,5 ml. B.4.4 Determination Transfer the test portion quantitatively to the distillation flask (B.3.1.11, add ff su icient toluene or xylene (B.2.1) (about 75 ml) to cover the test portion completely and swirl to mix. Assemble the appar
14、atus and fill the receiver (B.3.1.3) with the solvent (B.2.1), pouring it through the condenser (B.3.1.2) until it begins to overflow into the distillation flask. Start the flow of cold water. Heat the flask so that the distillation rate is about 4 drops per second. Continue heating until all the wa
15、ter has collected in the graduated part of the receiver. Purge the reflux condenser occasionally during the distillation, using 5 ml of the solvent to wash down any moisture adhering to the walls of the con- denser or receiver. The water in the receiver may be made to separate from the solvent by oc
16、casionally moving a spiral copper wire up and down in the condenser and receiver. Continue the distillation until the water level in the receiver remains unchanged for 15 min and then stop heating. Immerse the receiver in water at room temperature for at least 15 min or until the solvent layer becom
17、es clear, and then read the volume of water to the nearest 0,l ml. 8.5 Expression of results The moisture content, expressed as a percentage by mass, is equal to 100 v where m is the mass, in grams, of the test portion; V is the volume, in millilitres, of water collected. NOTE - It is assumed that t
18、he density of water is exactly 1 g/ml. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/26/2007 22:13:58 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 6756
19、4984 (El B.6 Test report tional, as well as any incidents that may have influenced the result. The test report shall show the method used and the result ob- tained. It shall also mention any operating conditions not specified in this International Standard, or regarded as op- The test report shall i
20、nclude all the information necessary for the complete identification of the sample. Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/26/2007 22:13:58 MDTNo reproduction or networking perm
21、itted without license from IHS -,-,- This page intentionally left blank Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/26/2007 22:13:58 MDTNo reproduction or networking permitted without license from IHS -,-,-