Patent Application
20070277814
This invention is directed to a lecithinated sugar composition, to a process for increasing the yield of raw sugar from a clarified sugar juice, and to a process for increasing the yield of refined sugar from raw sugar. Addition of a water dispersible lecithin increases the yield of raw or refined sugar and further, during the evaporation stage in both the raw sugar and the refined sugar processes, the viscosity of the syrups is decreased.
Lecithin is regarded as a well-tolerated and non-toxic surfactant. Commercial lecithin is a mixture of phospholipids as defined in Formula (I). Lecithin is obtained by degumming crude vegetable oil. A major source of lecithin is soybean oil. The term lecithin itself has different meanings when used in chemistry and biochemistry than when used commercially. Commercially, it refers to a natural mixture of neutral and polar lipids. Phosphatidylcholine, which is a polar lipid, typically is present in commercial lecithin in concentrations of about 5 to about 90%.
Lecithins are produced from vegetable, animal and microbial sources, but mainly from vegetable sources. Soybean, sunflower and rapeseed are the major plant sources of commercial lecithin. Soybean is the most common source. The main phospholipids in lecithin are phosphatidylcholine, phosphatidylethanolamine, phosphatidic acid, and phosphatidylinositol, as shown as Formula (I).
wherein R1 and R2 are fatty acid residues and G is selected from the group consisting of
Lecithins having utility within the present invention are water-dispersible lecithins and are selected from the group consisting of acylated lecithins, oil-free lecithins, enzyme-modified lecithins, fractionated lecithins, and hydroxylated lecithins. Preferred is a hydroxylated lecithin.
Lecithins employed in the present invention have a hydrophilic-lipophilic balance (HLB) of from about 4 up to about 13, preferably from about 5 up to about 12 and most preferably from about 7 up to about 12. Examples of lecithins suitable for the present invention are SOLEC™ CA® lecithin, SOLEC F lecithin, SOLEC K-EML lecithin, SOLEC HR lecithin, SOLEC S lecithin, SOLEC A lecithin, SOLEC CPS lecithin, and SOLEC E lecithin, all of which are available from Solae, LLC, St. Louis, Mo.
The present invention is directed to a sugar composition containing not more than 200 parts per million lecithin in the sugar composition and to processes for increasing the yield of raw or refined sugar from sugar-containing plants as exemplified by sugar cane, sugar beets, sweet sorghum and maple. Regardless of the plant, ultimately a clear sugar stream is the starting material for the two process embodiments of the present invention. Preferably the sugar composition, as prepared by the above processes, contains not more than about 100 parts per million lecithin in the sugar composition.
As shown schematically in
The macerated material leaving the macerating apparatus comprises pulp (i.e., fibrous material from the cane) and aqueous liquid that contains sucrose as well as other substances. This material is passed through a separator 5 for separation of the liquid (sucrose containing juice stream 8) from the fibrous pulp (bagasse). The separator can suitably be a centrifuge, filter, or screen (e.g., a rotating or vibrating screen, or a Dorr-Oliver DSM screen), or a combination of two or more of these.
The resulting bagasse may be dried and packaged for use as a fiber in papermaking or may be used as fuel for conventionally firing the steam boilers of the sugar mill.
After separation of the fibrous pulp from the liquid, the process can optionally include an additional step or steps to remove residual cane and silt from the separated liquid (juice). This can be done by screening and/or filtration. Preferably the screening or filtration removes at least about 90% by weight of all fibers and silt having a largest dimension of about 150 μm or greater, more preferably at least about 90% by weight of all fibers and silt having a largest dimension of about 50μ or greater.
The juice stream 8 is about 12-18° Brix, depending upon geographical location, age of cane, variety, climate, cultivation, condition of juice extraction system, and other factors. As dissolved material, it contains in addition to sucrose, some invert sugar, salts, silicates, amino acids, proteins, enzymes, and organic acids. The juice stream carries in suspension cane fiber, field soil, silica, bacteria, yeasts, molds, spores, insect parts, chlorophyll, starch, gums, waxes, and fats. Its color is brown and muddy with a trace of green from the chlorophyll.
The juice stream 8 exits the separator and is pumped to a heating tank 11. The sucrose is inverting under the influence of native invertase enzyme. This inversion is halted at 16 by raising the pH of the juice stream to between about 6-8 by the addition of lime (calcium hydroxide) and heating to at least about 100° C. to inactivate the enzyme and stop microbiological action. This stream is subjected to sulfitation 20 to remove impurities and for decolorization. The sulfitation can take place at one or more points in the process, for example, at the time of macerating the cane, in the juice after it is separated from the pulp, and/or in the feed to the evaporator. Most preferably, the sulfitation is done prior to clarification. Sulfitation is carried forth with an agent selected from the group consisting of sulfur dioxide, sulfite salts, bisulfite salts, metabisulfite salts, dithionites, and mixtures thereof, in an amount sufficient to provide an equivalent concentration of sulfur dioxide in the stream of at least about 100 ppm.
Sulfur dioxide, as well as the other named sulfitation agents, acts as an antimicrobial agent, and assists in the coagulation of such substances as albumin present in the juice. Further, the sulfur dioxide makes it possible to use more lime in the clarifying operation 23. Lime functions in several ways: adjusting the pH of the juice, forming insoluble compounds with several of the impurities present, neutralizing organic acids present, and when added in sufficient quantity, also reacting with any glucose present, converting it to organic acids. Most of the calcium compounds formed are quite insoluble and thus can be removed by settling or filtration. When phosphoric acid is added, the insoluble tricalcium phosphate is formed. The control of pH is critical if all lime is to be removed from the juice.
Within the cane sugar process, multiple stages of filtration 27 after clarification may be implemented, such as filtration using filter aid, ultrafiltration, nanofiltration, diafiltration, ion exchange, and/or electrodialysis. For example, the first filtration could take place in two or more stages of filtration, rather than taking place as a single filtration. Those skilled in the art will recognize that many other variations on the described process are also possible. It should also be recognized that the process can be operated at a variety of temperatures and other process conditions. The purpose of sulfitation, clarification, and filtration is to obtain a clarified sugar juice stream. The clarified sugar juice stream 31 has a concentration of from about 13° to about 18° Brix.
As shown schematically in
Upon leaving the diffuser, the raw juice moves through various stages of purification and filtration to remove non-sugars. It is first heated to 85° C. at 118 and sent to a prelimer 123, where most of the non-sugars are precipitated by gradual pH elevation. From preliming, the juice flows through a main limer 127 where the remainder of the lime is added on its way to the first carbonation station 130. Here carbon dioxide gas is bubbled through the limed juice where it reacts with the lime to form calcium carbonate and adsorbs some of the non-sugars.
The carbonated juice flows to a clarifier 133 where the precipitated calcium carbonate formed in the first carbonation is settle out. The resulting carbonated juice is sent to heaters 135 and on to the second carbonation step 137. In the second carbonation system, carbon dioxide gas is again bubbled through the juice, reacting with residual lime to form calcium carbonate precipitate within the carbonated juice. The amount of gas is controlled by pH to obtain the proper alkalinity and the carbonated juice is sent to the second carbonation filters 141 where the calcium carbonate precipitate is removed. The carbonated juice moves on to sulfitation 148 where sulfur dioxide is added to the juice to remove any color forming materials that would carry through to the finished sugar, and to adjust the pH to allow for easier boiling in the evaporation and vacuum pans, to give the clarified sugar juice stream.
As shown schematically in
A water dispersible lecithin 208 having an HLB of from about 4 up to about 13, is added to the concentrated clarified sugar stream 210. The lecithin is added at from about 0.1 kilograms up to about 2.0 kilograms and preferably at from 0.5 kilograms up to about 1 kilogram per 10,000 liters of a massecuite. The term “massecuite” as defined above, is a mixture of sugar liquor and sugar crystals that is formed in the vacuum pans. The lecithinated concentrated sugar juice stream is then pumped to vacuum units or pans. A quantity of fine sugar crystals used as a footing or seed 214 is then added to the lecithinated concentrated sugar juice stream. This stream is then crystallized in vacuum pan A 218 to produce a strike A massecuite, which when centrifuged at 222 produces sugar crystals A and molasses A. The sugar crystals A are conveyed from the centrifuge to a sugar storage bin 225 as raw sugar. The molasses A is fed to a second vacuum pan 228 together with some footing or seed crystals where it undergoes further evaporation to obtain a strike B massecuite. Massecuite B, containing sugar crystals B and molasses B, is centrifuged at 231 to separate the sugar crystals B from the molasses B, with the sugar crystals B sent to the sugar storage bin 225 to be combined with the sugar crystals A in order to obtain the raw sugar. The molasses B is fed to a third vacuum pan 235 together with some footing or seed crystals where it undergoes further evaporation to obtain a further strike C massecuite. The massecuite C, containing sugar crystals C and molasses C, is centrifuged at 239 to separate the further sugar crystals C from the molasses C, now called blackstrap molasses 243, with the sugar crystals C to be used as footing or seed crystals 214.
The water dispersible lecithin, having an HLB of from about 4 up to about 13, can be added to the clarified sugar juice stream, to any of the vacuum pans prior to crystallization, or to both the clarified sugar juice stream and to the vacuum pans prior to crystallization. Further, when added to the vacuum pan, the lecithin may be added to vacuum pan A, vacuum pan B, vacuum pan C or any combination of vacuum pans A, B and C, to increase sugar yield. Lecithin is added in an amount of from about 0.1 kilograms up to about 2 kilograms and preferably at from about 0.5 kilograms up to about 1 kilogram per 10,000 liters of massecuite.
Shown schematically in
The melter liquor is optionally strained through a screen to remove any debris that is present. In step (g), the melter liquor or screened melter liquor, if so screened, is then clarified at 335, generally by the successive steps of clarification, filtration and decolorization to produce clarified melter liquor 339. The clarification step usually involves forming an inorganic precipitate in the liquor, and removing the precipitate and along with it insoluble and colloidal impurities which were present in the melter liquor. In one of the clarification processes commonly used for melter liquor, termed “phosphatation,” the inorganic precipitate is calcium phosphate, normally formed by the addition of lime and phosphoric acid to the liquor. The calcium phosphate precipitate is usually removed from the liquor by flotation, in association with air bubbles. Other clarification processes, termed carbonation (or carbonatation) processes, involve adding lime and carbon dioxide to the liquor to produce calcium carbonate precipitate.
The color of the clarified melter liquor 339 going into step (h), the evaporation step at 345, ranges from water white to slightly yellow. In many cases, the brix has become too low and the clarified liquor goes to evaporators to bring the brix to at least about 60°. The evaporation sequence is similar to that disclosed above in the raw sugar process.
After evaporation, to form an evaporated liquor, the evaporated liquor at step (i) is then pumped to the first vacuum pan 351. Water dispersible lecithin 346 having an HLB of from about 4 up to about 13, is added to the evaporated liquor at 351 to form a lecithinated evaporated liquor. A quantity of fine sugar crystals 375, used as a footing or seed, is then added to 351. The lecithinated evaporated liquor is then crystallized to produce a strike A massecuite, containing sugar crystals that is centrifuged at 361 to separate the sugar crystals A from the molasses called molasses A. In step (j), the sugar crystals A are conveyed from the centrifuge to a sugar storage bin 380 as refined sugar while the molasses A in step (k) is fed to a second vacuum pan 353, together with some footing or feed crystals from 375, where it undergoes further evaporation to obtain a strike B massecuite. Massecuite B is centrifuged at 363 to separate the sugar crystals B from the molasses B, with sugar crystals B sent to the sugar storage bin to be combined with the sugar crystals A in order to obtain the refined sugar. The molasses B is fed to a third vacuum pan 355 together with some footing or feed crystals from 375 where it undergoes further evaporation to obtain a strike C massecuite. The massecuite C is centrifuged at 365 to separate the sugar crystals C from the molasses now called molasses C or blackstrap molasses 371, with the sugar crystals C to be used as footing or seed 375.
The water dispersible lecithin, having an HLB of from about 4 up to about 13, can also be added to a step selected from the group consisting of (e), (f), (g), and mixtures thereof, or to any of the vacuum pans prior to crystallization, or to the vacuum pan priors to crystallization and to any step selected from the group consisting of (e), (f), (g), and mixtures thereof. Within the vacuum pans, lecithin may be added to vacuum pan A, vacuum pan B, vacuum pan C or any combination of vacuum pans A, B and C, to increase sugar yield Lecithin is added in an amount of from about 0.1 kilograms up to about 2 kilograms and preferably at from about 0.5 kilograms up to about 1 kilogram per 10,000 liters of massecuite.
The equipment used in accomplishing the process of this invention is, in general, standard and readily available from usual suppliers. Evaporators, grainers, crystallizers and centrifuges, are all long used tools of the sugar refiners' art.
The efficacy of the present invention resides in an increase of theoretical yield of a sugar process. This increase in theoretical yield relates to the equation below.
r=[100(j−m)/j(100−m)]×100
wherein
r=% theoretical yield,
j=% juice purity, and
m=% honey purity
The following examples serve to illustrate the invention in more detail although the invention is not limited to the examples. Unless otherwise indicated, parts and % signify parts by weight and % by weight, respectively.
This example is directed to a sugar process that uses a two vacuum pan system to produce white sugar. In order to measure the yield increase of the process, both the massecuite B (as a j value) and molasses B purity (as an m value) are measured. Data is collected for four days prior to lecithin addition. The lecithin is added to vacuum pan B beginning at day 5 at from one kilogram of hydroxylated lecithin per 10,000 liters of massecuite B. Lecithin addition is continued for six days and then stopped. Data continues to be collected for two days after lecithin addition is complete. The results are shown in Table 1 below and in
Addition of the lecithin results in an increase in the sugar yield. During this Example 1, the addition of lecithin to massecuite B causes the yield of sugar to increase from an average of 52.6% before lecithin addition for days 1 through 4 to an average of 54.2% during the lecithin addition for days 5 through 10.
This example is directed to a sugar process that uses a two vacuum pan system to produce white sugar. In order to measure the yield increase of the process, both the massecuite B (as a j value) and molasses B purity (as an m value) are measured. Data is collected for seven days prior to lecithin addition. The lecithin is added to vacuum pan B beginning at day 8 at from one kilogram of hydroxylated lecithin per 10,000 liters of massecuite B. Lecithin addition is continued for seven days and then stopped. Data continues to be collected for seven days after lecithin addition is stopped. The results are shown in Table 2 below and in
Addition of the lecithin again results in an increase in the sugar yield. During this Example 2, the addition of lecithin to massecuite B causes the yield of sugar to increase from an average of 53.1% before lecithin addition for days 1 through 7 to an average of 58.9% during the lecithin addition for days 8 through 14.
While the invention has been explained in relation to its preferred embodiments, it is to be understood that various modifications thereof will become apparent to those skilled in the art upon reading the description. Therefore, it is to be understood that the invention disclosed herein is intended to cover such modifications as fall within the scope of the appended claims.
