ANNEXSupplementary provisions
SPECIFICATIONS OF TREHALOSE Synonyms α,α-trehalose Definition A non-reducing disaccharide that consists of two glucose moieties linkes by an α-1,1-glucosidic bond. It is obtained from liquefied starch by a multistep enzymatic process. The commercial product is the dihydrate. Chemical name α-D-glucopyranosyl-α-D-glucopyranoside, dihydrate CAS No 6138-23-4 (dihydrate) Chemical formula >REFERENCE TO A GRAPHIC> (dihydrate) Structural formula Trehalose >PIC FILE= "L_2001269EN.001802.TIF"> Formula weight 378,33 (dihydrate) Assay Not less than 98 % on the dry basis. Description Virutally odourless, white or almost white crystals with a sweet taste Characteristics Identification Solubility Freely soluble in water, very slightly soluble in ethanol Specific rotation [α]D20 + 199° (5 % aqueous solution) Melting point 97 °C (dihydrate) Purity Loss on drying Not more than 1,5 % (60 °, 5h) Total ash Not more than 0,05 % Lead Not more than 1 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the principles of the method described in FNP 5(1), "Instrumental methods" Method of assay Principle: trehalose is identified by liquid chromatography and quantified by comparison to a reference standard containing standard trehalose Preparation of sample solution: weigh accurately about 3 g of dry sample into a 100-ml volumetric flask and add about 80 ml of purified, deionised water. Bring sample to complete dissolution and dilute to mark with purified deionised water. Filter through a 0,45 micron filter Preparation of standard solution: dissolve accurately weighed quantities of dry standard reference trehalose in water to obtain a solution having known concentration of about 30 mg of trehalose per ml Apparatus: liquid chromatograph equipped with a refractive index detector and integrating recorder Conditions: Column: Shodex Ionpack KS-801 (Showa Denko Co.) or equivalent - length: 300 mm - diameter: 10 mm - temperature: 50 °C Mobile phase: water flow rate: 0,4 ml/min Injection volume: 8 μl Procedure: inject separately equal volumes of the sample solution and the standard solution into the chromatograph. Record the chromatograms and measure the size of response of the trehalose peak Calculate the quantity, in mg, of trehalose in 1 ml of the sample solution by the following formula: >REFERENCE TO A GRAPHIC> where RS= peak area of trehalose in the standard preparation RU= peak area of trehalose in the sample preparation WS= weight in mg of trehalose in the standard preparation WU= weight of dry sample in mg (1) Food and nutrition paper 5 Rev.2 - Guide to specifications for general notices, general analytical techniques, identification tests, test solutions and other reference materials (JECFA) 1991, 322p. English - ISBN 02991.