Kvasny Prum. 1959; 5(6): 139-144 | DOI: 10.18832/kp1959016

Comparison and evaluation of various methods for determination of sugar contents in wine wort.Peer-reviewed article

Z. KUTTELVAŠER, J. JAROŠ

By checking the precision of various methods applied for determination of sugar contents in wine wort it has been found by means of statistical analysis, that the readings taken from a wort tester of Klosterneuburg type do not exceed the limits of standard measuring errors and are not far from the real sugar contents. There is a good conformity between the values thus obtained and refractometer readings multiplied according to formula ⁰Rf x 0,85 as well as with the direct calculation of sugar contents from tables introduced by MEOPTA works. If Špreňar`s tables are used for calculation, the results deviate substantially from the average real value and cannot be therefore relied on. The Voskobojnikov`s tables show maximum deviation of values obtained by testing from ideal average value towards higher contents. By comparing figures arrived at by calculation, readings from testers and results of analysis applied to a given batch of wort, it has been found that the values calculated from the formula (⁰Oe : 4) - 2 are more realistic than the figures obtained from another formula viz. (⁰Oe : 4) - 3,  though the latter formula is widely used. The first formula provides results which do not differ substancially from the Klosterneuburg tester readings. If the sugar contents of wort is measured by a tester adjusted at 15 °C, no correction for temperature is necessary since it should not exceed the limits of measuring errors. Should the tester be adjusted at 20°C,it is advisable to consult correction tables for temperature as the difference might be sometimes significant, being always in favour of party selling the wort. Since the values calculated by refractometric method from the dry matter contents are comparatively correct, the author recommends to verify the method by introducing it in practice and  to determine the final figures either by using the suggested formula (⁰Rf x 0,85), or from the MEOPTA tables.
(In Czech, English summary only)

Keywords: sugart contents, must, determination

Published: June 1, 1959