Sugar Factory Definitions Official Methods for the Determination and Distribution of Sucrose in Cane Bagasse The residue obtained after crushing cane in a mill is known as bagasse. Depending on the number of the mill it is referred to as first mill bagasse, second mill bagasse, etc. After a diffuser the residue is called diffuser bagasse. The final residue from a milling train or from the dewatering mills of a diffusion plant is called final bagasse or simply, bagasse. Bagasse Extract The liquid fraction decanted from the bagasse after blending with water in the colddigester. Brix Refractometer brix The term used when a refractometer equipped with a scale,based on the relationship between refractive indices at 20\u00b0C and the percentage by mass of total soluble solids of a pure aqueous sucrose solution, is used instead of a hydrometer to test the solids concentration of a sucrose containing solution. The South African sugar industry is now standardised on refractometer brix. The changefrom hydrometer brix was completed in the 1972/1973 season. Brix-Free Water The water associated with the fibre in cane and bagasse. In some respects this sorpfionwater behaves in a manner similar to water of hydration and it is not available for dissolving sucrose. It is driven off at elevated temperatures. The amount of brix-free water is assumed to be 25% on dry fibre. DAC Extract The liquid fraction decanted from the cane after blending with water in the cold digester. DAC Factors Brix Factor: The percentage ratio of the total brix in mixed juice, final bagasseand where applicable, diffuser press water mud, to total brix in cane as determined by direct analysis. Pol Factor The percentage ratio of the total pol in mixed juice, final bagasseand where applicable, diffuser press water mud, to total pol in cane as determined by direct analysis. Fibre The water insoluble matter of cane and bagasse from which the brix-free water has beenremoved by drying. Where associated with brix-free water, fibre is often called natural fibre. DAC fibre Fibre % cane derived from direct cane analysis and applying the formula
Fibre % cane = (100-M-3b)/(1-0.0125b)
in which M= moisture % cane b= brix % extract Insoluble Solids Insoluble material in mixed juice or press water mud, determined gravimetrically byfiltration according to a prescribed method.
Intermixed Cane That portion of cane on a cane carrier originating from the overlapping of differentconsignments. Its composition is unlikely to be representative of anyone consignment and it is therefore excluded from consignment sampling. Juice Mixed juice The mixture of juices from the extraction plant delivered into the juice scales. Press water The juice expressed in dewatering diffuser bagasse. Mud The material removed from the bottom part of the subsiders. The mud contains the settled insoluble solids. Normal Mass The mass of sample equal to the normal mass of sucrose. That mass of pure dry sucrose which, when dissolved in water to a total volume of 100cm3 at 20\u00b0C and read at the same temperature in a tube 200 mm long, gives a reading of 100 degrees on a saccharimeter scale. According to the International Sugar Scale the normal mass of sucrose is 26,000 g. Pol The apparent sucrose content of any substance expressed as a percentage by mass and determined by the single or direct polarization method. The term is used as if it were a real substance. Purity The percentage ratio of sucrose (or pol) to the total soluble solids (or brix) in a sugar product. The following terms are in general use: Refractive apparent purity: The percentage ratio of pol to refractometer brix. G.C. sucrose refractometer brix purity: The percentage ratio of GC sucrose to refractometer brix. Sucrose The pure disaccharide \u03b1-D-glucopyranosyl-\u03b2-D-fructofuranoside, known commonly sugar. In the South African Sugar Industry sucrose is determined by GC. Sugar Cane Botanically a tall grass of the genus Saccharum and agriculturally the crop produced from hybrids which are the progeny of a number of Saccharum species commonly referred to as cane. Specifically for the determination and distribution of sucrose in cane it is the raw material accepted at the mill for processing. Definitions as applied to the Methods for Factory Control Ash Carbonated ash: The residue remaining after incineration at 650\u00b0C. Conductivity ash: The conductivity ash of a product is the figure arrived at bycorrelating the specific conductance of the solution of that product with its sulphated ash. Sulphated ash: The residue remaining after incineration at 650\u00b0C of a samplewhich was pre-treated with sulphuric acid. Attenuation Index
The absorbance of a solution obtained at a specified wavelength expressed per unit celllength and unit concentration, e.g. a*c420 = OD/b\u00b7c\u00b710 where a*c420= attenuation index at 420 nm wavelength of light OD = absorbance b= cell length (mm) c= concentration (g/cm3) Bagacillo Very small particles of bagasse separated either from pre-clarification juices or from thefinal bagasse for filtration or other purposes. Boiling House That part of the factory in which the processes of manufacture from mixed juice to sugarare carried out. Boiling House Recovery The percentage ratio of pol actually recovered in sugar to sucrose in mixed juice. Ifbased on pol in mixed juice it is referred to as Boiling House Pol Recovery. Brix (Degrees) Unit divisions of the scale of a hydrometer, which, when placed in a pure aqueous sucrosesolution at 20\u00b0C, indicates the percentage by mass of dissolved solids in the solution. The reading obtained in an impure sucrose solution is usually accepted as an approximation of its percentage by mass of total soluble solids. The term brix is used in calculations as a measure of substance, e.g. tons brix. Bulk Density The mass of material per unit of total volume occupied. See density tables for some useful values Cane to Sugar Ratio Tons cane required to produce one ton of tel quel sugar. Crystal Content The percentage by mass of crystalline sugar present in a massecuite, magma or similarmaterial. Cush-Cush The material removed from mill juice by straining. Dextran A polysaccharide consisting of glucose units linked predominantly in \u03b1-(1\u21926)mode. sometimes present in appreciable concentrations in sugar cane and mill products due to microbial activity. Dry Substance The material remaining after drying a product to constant mass, or for a specified period. The mass of dry substance can also be found by deducting from the mass of the product, the mass of moisture, as determined in a specified manner. Escribed Volume The volume escribed by a pair of mill rolls in a given time. It is equal to the rollerlength (in m) multiplied by the work opening (in m) multiplied by the surface speed of the rolls measured at the mean circumference (in m/sec) and is expressed in m3/sec. Extraction
The percentage ratio of sucrose in mixed juice to sucrose in cane. If based on pol it isreferred to as Pol Extraction. Corrected reduced extraction (CRE): Sometimes used to correct for the influenceof sucrose and fibre on extraction and is calculated by the following formula: CRE = 100 - (0.03936×(100 - E)×(100-Fc)×Pc0.6)/Fbc
Where E= Extraction Pc= Sucrose % cane Fc= Fibre % cane (including insoluble solids in mixed juice) Fbc= Fibre in bagasse % cane (excluding insoluble solids in mixed juice) If based on pol it is referred to as Corrected Reduced Pol Extraction Estimated Recoverable Crystal (ERC) The formula for ERC is ERC=aS-bN-cF
where S=sucrose%cane N=non-sucrose%cane F=fibre%cane a = (polbagasse + polsugar + sucrosemolasses) / sucrosecane b = sucrosemolasses / non-sucrosecane c = polbagasse / fibrecane
Factors a, b, and c may vary slightly from year to year. Hence values are calculated atthe end of every season using weighted averages and assuming that ERC is equal to the total crystal production of the industry. Filter Cake The residue removed from process by filtration including any added filter aid. Gums The precipitate, corrected for ash, consisting mainly of polysaccharides, which isobtained by treating sugar liquors with acidified ethyl alcohol. Imbibition The process in which water or juice is put on bagasse to mix with and dilute the juicepresent in the latter. The water so used is termed imbibition water. General terms in use are: single imbibition, double imbibition, compound imbibition, depending on the manner in which the water and / or juice is added. Invert Sugar A mixture of fifty percent glucose and fifty percent fructose obtained by the hydrolysisof sucrose. Java Ratio The percentage ratio of pol % cane to pol % first expressed juice. Note: In calculating an average pol % first expressed juice the weighting given to theindividual analyses is on the basis of the tons cane from which the respective first expressed juice samples were taken.
Juice •
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Absolute juice: A hypothetical juice, the mass of which is equal to the mass of cane minus the mass of fibre. It comprises all the dissolved solids in the cane plus the total water in cane. Clarified juice: The juice obtained as a result of the clarification process. Diffuser juice, also called draught juice: The juice which is withdrawn from a cane or bagasse diffuser.
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First expressed juice: The juice expressed by the first two rollers of a tandem.
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First mill juice: The juice expressed by the first mill of a tandem.
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Last expressed juice: The juice expressed by the last two rollers of a tandem.
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Last mill juice: The juice expressed by the last mill of a tandem.
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Primary juice: All the juice expressed before dilution begins.
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Residual juice: The juice left in intermediate or final bagasse.
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Secondary juice: The diluted juice which, together with the primary juice, forms the mixed juice. Undiluted juice: All the juice existing as such in the cane. Its mass is equal to the mass of cane minus the combined mass of fibre and brix-free water.
Maceration In the South African sugar industry the term is synonymous with imbibition. The latter isthe preferred terminology. Magma A mixture of crystals and sugar liquor produced by mechanical means. Massecuite The mixture of crystals and mother liquor discharged from a vacuum pan. Massecuites areclassified in order of descending purity as first, second, etc., or A, B, etc . Mill Settings Mean circumference: mean diameter × π. Mill ratio: The ratio of feed to discharge work openings. Set opening: The distance between the circumferences escribed by the meandiameters of the top roller and feed or discharge roller with the mill running empty. This definition applies pari passu for the openings between underfeed and top roller and between pressure feeder rollers. The mean diameter of a grooved roller is equal to the diameter of the equivalent (samevolume and length) solid roller. In practice the arithmetic mean of the diameters over the tips of the teeth and at the roots of the grooves (neglecting any Messchaert grooves) affords a sufficiently close approximation.
Work opening: The work opening is equal to the set opening plus the increase indistance between the rollers resulting from the lift during milling operations. Milling Loss The percentage ratio of pol in bagasse to fibre in bagasse. Molasses The mother liquor separated from a massecuite by mechanical means. It is distinguished bythe same prefixes as the massecuites from which it is separated. Final molasses: The mother liquor separated from the final massecuite bymechanical means. Non-Pol Brix minus pol. Non-Pol Ratio The ratio between non-pol in sugar plus non-pol in final molasses and non-pol in mixedjuice. Non-Sucrose Dry substance minus sucrose. Nutsch Sample Any sample of molasses which is separated from a massecuite at any time prior to curingthe massecuite in the factory centrifugals. Overall Recovery* The percentage ratio of pol actually recovered in sugar to sucrose in cane. If based onpol in cane it is referred to as overall Pol Recovery. Polysaccharides Polymers of medium to high molecular mass in which the units are mainly pentoses and/orhexoses. Preparation Index The percentage ratio of brix in the ruptured cells to total brix in cane. Purity
The percentage of sucrose in total solids in a sugar product. The following purity termsare in general use: Purityapparent = pol / brix · 100 Puritygravity = sucrose / brix · 100 Puritytrue = sucrose / total solids · 100
In order to specify purity without ambiguity it is necessary to indicate the methods usedto determine both the numerator and denominator in obtaining the result. Target purity: A reference purity of final molasses taking into account theeffect of the non-sucrose present on its exhaustion. In South Africa the formula reads: Puritytarget = 33.9 - 13.9·log[(f + g)/a] Where f = fructose % molasses (determined by GC)
g = glucose % molasses (determined by GC) a = sulphated ash % molasses Target purity difference: The difference between the true purity as determinedfrom GC sucrose and Karl Fischer solids and the target purity as calculated above. Reducing Sugars Reducing sugars are sugars which reduce Fehlings solution. In the Lane & Eynon methodthe test sample (containing sucrose & invert sugar) is added volumetricly to a defined volume of a strongly alkaline cupric-complex salt solution, called Fehling's solution, which is then reacted by boiling. The remainder of the test solution is then added, until, at the end-point, the cupric ions are completely REDUCED to cuprous oxide and a blue color of the solution will disappear. The sharpness of the end-point is improved by the use of an indicator, methylene blue, which is decolorized in the presence of a minute excess of reducing sugars. Glucose and fuctose (also referred to as invert sugar or just invert) reduce the cupricions therefore they are refered to as reducing sugars. Sucrose does not reduce the cupric ions and hence is refered to as non-reducing. Reducing Sugar/Ash Ratio The ratio of reducing sugars to sulphated ash. Reducing Sugar/Pol Ratio The percentage ratio of reducing sugars to pol and often referred to as reducing sugarratio. Safety Factor A number designed to indicate the probable keeping quality of a fresh raw sugar having apol of less than 99,0°S. It is calculated by dividing the percentage moisture in the sugar by 100 minus the pol of the sugar. For satisfactory keeping quality the safety factor should have a value less than 0,23. Saturated Solution A saturated solution is one which would neither dissolve nor crystallise solute in thepresence of undissolved solute. Soil In Cane And Bagasse Inorganic material determined by ashing a sample and correcting for the ash % cleansample. Solubility The concentration of a solute in a solvent in a saturated solution. It is dependent ontemperature, the nature and concentration of impurities and in the case of gases, on pressure. Solubility Coefficient Of Sucrose The ratio of the solubility of sucrose in the sample to that in pure water at the sametemperature (both expressed as g sucrose/g water). Sugar The main product of a sugar factory consisting of crystals of sucrose as removed from amassecuite and containing more or less impurities, depending on the type of sugar.
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Refined sugar: A white sugar as specified in Table 15.
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Very high pol sugar (VHP): Raw sugar with a pol of not less than 99,3°S.
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High pol sugar (HP): Raw sugar with a pol between 98,0 and 99,3°S.
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Low pol sugar (LP): Raw sugar with a pol below 98,0°S.
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Brown sugar: A direct consumption raw sugar.
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Tel quel sugar: The bulk product without reference to its quality.
Sugar Cane Botanically a tall grass of the genus Saccharum and agriculturally the cropproduced from hybrids which are the progeny of a number of Saccharum species commonly referred to as cane. Specifically for the determination and distribution of sucrose in cane it is the raw material accepted at the mill for processing. •
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Clean cane stalk: Cane which has been cut above the highest subterranean roots ; has been topped below the level of the growing point; has no leaves or adhering foreign matter and has not died and dried out. Cane tops: The portion of the stalk above the natural breaking point, plus all green leaves and sheaths attached to that part of the stalk. Extraneous matter: Any solid material delivered with clean cane stalk, including dead and dried out stalks. Trash: Leaves and sheaths delivered with the clean cane stalk.
Supersaturation Coefficient Of Sucrose The ratio of the concentration of sucrose in the sample to the solubility of sucrose inthe sample at the same temperature (both expressed as g sucrose/ g water). Syrup Concentrated clear juice having a brix of between 60° and 70°. Total Solids The solids concentration of an aqueous solution determined either by drying or byanalysing for the water content using the Karl Fischer method. Wash
The diluted liquor thrown off by the centrifugals during washing and/or steaming ofmassecuites or the total liquor separated from a magma. Source: Southern African Sugar Technologists Association Laboratory Manual
Density of Sugar Factory Products The tables below give the approximate range of densities for selected cane factory products. This data is taken from multiple sources including Hugot and Tromp
Sugar Cane
lb/ft3 kg/m3
Whole stick cane, tangled and tamped down as in a cane 12.5 200.2 transport vehicle Whole stick cane, neatly bundled
25
400.5
Billetted cane
22
352.4
Whole stick tangled cane but loosely tipped into cane carrier 10 160.2 Knifed cane
18
288.3
Shredded cane
20
320.4
Bagasse
lb/ft3 kg/m3
Bagasse exiting the final mill
7.5
Bagasse stacked to 2 metre height (moisture = 44%) 11
120.1 176.2
Sugars
lb/ft3
kg/m3
Sucrose crystal
99.0
1586.2
Amorphous sucrose
94.1
1507.7
Bulk white sugar
54.9
880
Bagged white sugar
43.7
700
Raw sugar (96° Pol) in a pile
56.2
900
Bagged raw sugar
42.4
680
