Zerban as chairman of the committee was accepted with regret, and the author was appointed to that office with Mr. It is hoped that the present edition will prove to be one of the first, and that its publication will serve to promote the good, selection. In some of these countries, sub-committees were set up to advise committee members.
Since the members of the committee are spread all over the world, it was necessary to carry out the work largely by means of questionnaires and correspondence. These reports were discussed at the conferences by the committee members or proxies present, and any agreed changes were introduced into the reports. In this book, the committee's reports have been reorganized and systematized so that they can be consulted more easily.
In some cases the original text has been somewhat compressed, in others amplified, always bearing in mind the intention of the Commission's work.
General Definitions
The brix of a solution of pure sucrose in water is a direct measure of the percentage of sucrose or solid by weight in the solution. Brix is then numerically the same as the percentage of solids in a pure sucrose solution of the same density. As in the case of sucrose (definition 6), the concept of dry matter is clear, and limitations in our ability to measure dry matter do not affect the significance of the term.
Matieres en suspension dans le jus melange', Sp.: Solidos en suspension en el jugo mezclado. All the dissolved solids in the cane plus the total water of the cane; cane minus fiber. The juice poured out of the mud or sediments during the clarification process.
Egout (pauvre) (first to penultimate molasses), Molasse (final molasses); Sp.: Miel; the final molasses is called Molasses or Miel final.
Principles of the Milling Control
The weight of imbibition or maceration water is then calculated according to the basic formula. The weight of absorbed water is calculated assuming that the percentage of absorbed water. This leaves either a direct determination of the weight of the absorbent water (method 1) or a direct determination of the fiber percentage.
This system completely eliminates the milling factor, which has been a problem in the sugarcane industry for many years. The requirements for accuracy and simplicity require that the composition of the bagasse be determined if possible. It is influenced by the character of the cane, especially the fiber and sucrose in the cane.
This makes it necessary to determine the Brix of the primary juice in addition to that of the mixed juice.
Determinations and Calculations for the Milling Control
Weight of absolute liquid extracted = 100 times the weight of Brix in mixed liquid (19), divided by percent Brix. Weight of absolute liquid in the bag = 100 times the weight of Brix in the bag (21), divided by percent Brix.
Control of the Boiling House
Cleanliness of filter cake.—This should be reported; pol separates with the dry substance. Only the weights of the various products should be reported on a cane mill basis (see p. 28). To avoid further confusion, the Committee recommends the term ``Basic Boiler House Recovery,'' as defined below, in place of the former term ``available.''
The committee defines the basic boilhouse recovery as the percentage of sucrose in the blended juice that would be obtained according to the s-j-m formula, with values of 100 and 28.57 for s and m, respectively, and for j, the gravity purity of the blended juice. Because Deerr has developed a better comparison figure than the 'Boiling House Performance', namely the 'Reduced Boiling House Recovery, E.G.S.', the committee has decided to make reporting on the Boiling House Performance optional. First, the "virtual" gravity purity of the molasses, mv, is calculated using the s-j-m formula from the observed gravity purity of the blended juice, j, and the actual recovery from the boil house, E.S.G., Y using the formula.
Similar conditions appear to apply to the methods of expressing the efficiency standard of the cooking house. This question was undoubtedly the reason for K.I.S.S.C.T.'s contribution on this subject. 8th Congress, 1953), which emphasized the effects of the composition and the amount of non-sucrose in blended juice. At the committee meeting this feature seemed to prevail in the minds of the delegates and the unanimous decision to retain the Deerr formula may have been influenced by this.
A disadvantage of the figure is that it is affected by errors in the weight of the molasses, but this can be detected from other data and taken into account. The components of the observed loss are (1) the result of clarification, that is non-sucrose (non-pol) in total molasses percent. In this way, the role played by each of the above components in the total cooking house loss can be established.
If someone wants to make the necessary calculations, he can easily do so on the basis of the analytical data that must be reported. This forms the first component of the old comparison figure of the J a v a Experiment Station, namely sucrose in molasses per cent.
The weight of trash must not under any circumstances be deducted from the weight of the cane entering the factory. If the juice is measured in the liming tanks, the amount of the milk of added lime must be deducted. Corrections when juice is weighed.-In J a v a the weight of the juice is corrected for suspended matter.
Corrections when measuring juice.-In this case a correction must be applied for the volume of the gases enclosed in the juice. If weighing the entire production is not practically possible, it is necessary to resort to sampling methods. Measurement of final molasses.--The Committee considers this method of arriving at the weight of the molasses to be inadmissible for control purposes.
The water evaporated in the effects is calculated from the weight of the original liquid, and the Brix of the syrup and original liquid in the usual way. Last expressed liquor.—The last expressed liquor, i.e., the liquor whose purity is used in the calculation of the Brix in the bagasse, should be sampled from the bagasse roll of the last mill. Sampling must be done manually and synchronized with the sampling of the relevant bagasse.
If we want to keep the original composition of the product unchanged, precautions must be taken to prevent the water content from changing. To control the centrifugal section, samples can be collected at regular intervals from the channel leading from the centrifuge to the molasses tanks. Fiber in pure cane.—The direct determination of fiber has been approved by the Committee as one of two methods of indirectly determining the weight of pastry.
Dry Matter in Bagasse.-The sample must be analyzed as soon as possible after taking to prevent loss of moisture. But on high-grade sugars the dry matter must be determined because the possible error in the Brix determination may exceed the total moisture content of the sugar. Until a simpler method is devised, the Brix of the bagasse should be calculated as shown in Chapter I I I.
The Hawaiian method probably does not give an accurate measure of suspended matter in undiluted molasses.
Of the alternative systems, the Americans and the British, which are identical in most respects, have the greatest significance for the sugar industry. Perhaps most common in sugar industry parlance are units of Hispanic origin. If this is attempted, it is necessary to recognize that there are minor disagreements about some of the basic figures, and that many of the relationships normally regarded as constant actually vary somewhat over different temperature ranges or other influential factors.
It behooves anyone seeking a high degree of accuracy to resort to more specialized publications that precisely state the conditions applicable to some relationships. The arroba is often cited as a measure of weight, although the actual weight of the arroba varies from country to country. Although minor differences may be observed between the corresponding tables published in different works, for the most part these differences arise from minor variations in the basic data used in the compilation of the tables, or from genuine disagreements about the facts.
In the last class we may mention such data as those relating to the densities of sugar solutions of different strengths at different temperatures. These arguments make it not only unnecessary but unwise to publish a set of standard tables in this book for the use of the world's sugar producers. Practical tables with a lower degree of accuracy, based on weight in air, are available in Circular C440 (1942) of the USA.
Probably the most generally accepted table of temperature corrections for Brix hydrometers is that printed in U.S. Circular 19 (1914). To the best of the writer's knowledge, it clarified that the correction table refers to spindles that have been previously calibrated to read concentrations. expressed in terms of weights in air. The actual data regarding the thermal expansion coefficients of sugar solutions used in this work were primarily Plato's.
For purposes of calculating the table based on Brix observed with a spindle standardized at temperature t, the denominator of the above expression may be equated to - mass in air 100 ml. Some of the Schmitz tables in use appear to have survived from an earlier time when the proper method of derivation was not clearly defined.
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