METHOD FOR DETERMINATION OF APPLE PUREE WEIGHT FRACTION IN MARMALADE AND SWEET JELLY BODY

FIELD: food industry.SUBSTANCE: method envisages weighing of a 1.5-2.5 g sample of marmalade or sweet jelly body. One places he sample in a 1000 ml measuring flask, adds 100-200 cm of 10 mmol/l solution of benzoic acid with temperature equal to 50-70°C. Then the mass is thoroughly stirred during 10-20 min until complete dissolution of the sample. The solution is diluted to volume with benzoic acid solution having concentration equal to 10 mmol/l and centrifuged during 10-15 min at a rate of 2500-3000 rpm. Then the transparent solution is removed into the vessel for study of organic acids composition by way of capillary electrophoresis with indirect detection using a buffer solution consisting of 8-12 mmol/l of benzoic acid, 8-10 mmol/l of diethylamine, 0.45-0.55 mmol/l of cetyltrimethylammonium bromide, 0.05-0.10 mmol/l of ethylenediaminotetraacetic acid, pH equal to 5.0-5.7; the capillary length is equal to 50-97 cm, the capillary effective length - to 43-90 cm, the capillary internal diameter - to 50-75 mcm; then one proceeds with the sample introduction with the values of the product of pressure and introduction time within the range of 200-1000 mbar*sec; detection is performed in a diode matrix detector, the thermostate temperature equal to 21-28°C and voltage - to 15-30 kV; calculation of the malic and tartaric acids peaks height is performed at wave length amounting to 230 nm. Then the apple puree weight fraction is determined from the formula:(1), where M - weight portion of apple puree in the product, %, m - weight of the product sample batch, g; h- sum total of the malic and tartaric acids peaks heights in the electrophoregramme of the organic acids standard solution with the weight fraction of each acid equal to 5 mg/l, transmission units; h- sum total of the malic and tartaric acids peaks heights in the electrophoregramme of the sample solution, transmission units; if the product sample contains other fruit components, the malic acid peak height is calculated as the tartaric acid peak height multiplied by a coefficient equal to 7.0 (according to reference data); 1.25 being the coefficient accounting for concentration of acids in the standard solution, the sample dilution and sum total of malic and tartaric acids in apple puree equal to 0.8% (according to reference data), g.EFFECT: determination of the apple puree weight fraction by the weight fraction of the organic acids complex and reduction of the amount of time spent on the operation perform