JPH0328479B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for refining crude vegetable oils. Among other things, the present invention relates to a method for refining impure crude oils and fats in order to yield essentially additive-free products with good oxidation stability, flavor stability and low temperature test stability. In the past, edible oils and fats obtained from animals were refined using physical refining methods. However, vegetable oils and fats could not be sufficiently purified by such methods. The wide variety of impurities contained in vegetable fats and oils can lead to undesirable properties in the final product, such as darkening of the color or altered flavor. Currently, the most common method for refining vegetable oils and fats is to treat the crude oils and fats with alkali. This alkaline purification removes free fatty acids and other acidic substances, some phospholipids, proteinaceous substances, pigments, and trace metals. Until recently, most oils and fats could only be satisfactorily deodorized by alkali purification. However, although alkaline refining is suitable as a preparatory treatment for further processing of various oils, such as bleaching and deodorization, it also has some serious drawbacks. Alkaline refining generally results in a large loss of neutral oil components of the crude oil, thereby reducing the yield of refined oil products. In addition, removal of free fatty acids by alkaline refining results in the production of soap raw materials,
This must be further processed to recover the fatty acids as a by-product. Furthermore,
Alkaline refining generally produces large amounts of wastewater, which often causes serious wastewater problems. Other,
Alkaline refined oils are treated with various stabilizers, typically antioxidants and citric acid, to ensure that the refined oil maintains acceptable flavor characteristics and prevents harmful oxidation during storage. I need. Alkaline refining also includes a dewaxing step, which increases the price of the refined oil. This additional step is a process for removing not only compounds classified as waxes in a strict chemical sense, but also so-called "waxes" which are insoluble at low temperatures. If a processing step is not employed to cool the fat and remove the solids formed, the final product fat will not exhibit acceptable low temperature test stability, i.e. such fat will not be exposed to 0°C for 24 hours. does not maintain good clarity during storage. Various methods for physically refining vegetable oils and fats have been proposed in recent decades. Some of these methods have already been successful with certain crude fats and oils containing limited amounts of various types of impurities. For example, U.S. Pat. No. 1,744,843 to Taylor et al. relates to a method of bleaching animal and vegetable fats or oils, which method consists of adding bleaching clay and sulfuric acid. In this method, the bleaching clay is added at least simultaneously with or before the added sulfuric acid, so that the fats and oils to be treated are exposed to the acid only in the presence of the bleaching clay, That will happen. The mixture is stirred and the supernatant oil layer is drawn off and passed through a layer of diatomaceous earth. Freiberg, U.S. Pat. No. 1,964,875, relates to an alkaline refining process, and this publication discloses one method for removing impurities from fats and oils, in which the fats and oils are treated with a small amount of concentrated phosphoric acid. mixed. The mixture is then slowly heated to about 70°C, stirred and a small amount of cellulose is added. Once the action of the added phosphoric acid and cellulose is complete, the fats and oils are separated and filtered. No. 1,973,790, issued to Mr. Appleton, relates to a method of refining non-edible vegetable oils to increase their thermal stability for use in paints. In this method, fats and oils are purified by mixing them thoroughly with phosphoric acid in sufficient quantities to react with impurities in the fats and oils. This causes such impurities to precipitate out and precipitate out of the oil in the form of a sludge. This refined fat is then separated from the sludge. Although U.S. Pat. No. 2,441,923, issued to Mr. Sullivan, is not per se directed to a physical refining process, it uses an acid-activated method, such as activated clay, to remove residual color from alkali-treated fats and oils. It is disclosed that adsorbent materials can be used. U.S. Patent No. 2510379 awarded to Mr. Christenson
The invention of this issue relates to a method for removing lecithin, other phospholipids, and coloring substances. After treating the fat with alkali, the fat is further treated with an equivalent amount of strong acid to remove the salt formed by the alkali and the added acid. Phosphoric acid and other strong acids are used to neutralize fats and oils (see column 2, lines 35-42).
This document also discloses the use of acid-activated bleaching clays (see column 4, lines 10-15). The invention of U.S. Pat. No. 2,587,254 to Mr. Babayan relates to a method for reclaiming contaminated waste palm oil used in steel manufacturing. According to this method, waste palm oil contains 1 to 5% by weight of phosphoric acid or
The oil is treated with either sulfuric acid or hydrochloric acid in water in an amount of at least 50% of the weight of the oil at a temperature of 0°C to 100°C. This mixture is separated into layers,
The oil layer is then separated from the aqueous layer and bleached. The invention of US Pat. No. 2,903,434 to Glose et al. does not relate to the purification of oils and fats, but rather to a method of refining activated bleaching clays. Montmorillonite clay is treated with an aqueous solution of a fluorine compound and with hydrochloric, phosphoric, or sulfuric acid. U.S. Patent No. Mickelson et al.
No. 2981697 discloses a method for preparing acid activated deodorizing clay. The acid activated subbentonite clay is treated with hydrogen chloride in an aqueous solution and then washed with water until substantially free of chloride ions. The aqueous clay is then treated with sulfuric or phosphoric acid at temperatures below about 50°C to remove residual chloride ions. Excess acid was removed from this clay and this clay was
Flash dry at temperatures below °C. U.S. Patent No. granted to Mr. Van Akkeren
No. 3,284,213 discloses a method for treating culinary triglyceride fats to inhibit decomposition and prevent foaming during heating. Approximately 0.05 for fats and oils
-3.5% concentrated phosphoric acid is added and the fat is slowly heated to a temperature of about 100°C and stirred gently to prevent the formation of free acid in the fat. Bleaching clay is added to the oil once the temperature of the oil reaches about 100°C, and the mixture is then heated to about 120°C for about 15-30 minutes. The oil is first cooled, filtered to remove clay and phosphoric acids, and then heated to about 220-225°C under reduced pressure. This document teaches that it is important to remove all phosphoric acid using bleaching clay prior to final heat treatment. Phosphoric acid: 1:10 of clay
The ratio up to can be calculated from the example. No. 3,354,188 to Rock et al., a refining agent that is substantially insoluble in the oil to be refined is first combined with an emulsifier, which is then mixed with the oil to be refined to form an emulsion. Discloses a method for refining oil. Particulate solids, such as acid clay, activated clay, or activated carbon, are then added to adsorb the refining agent and separate the fat from the solids. Phosphoric acid is listed among the refining agents. US Pat. No. 3,590,059 to Velan discloses a method for refining vegetable and animal fats and oils containing fatty acids or other impurities. First, the crude fat or gummy fat is washed with about 1 to 5% by weight of water, and the aqueous phase is separated from the resulting mixture. This washed oil is then treated with, for example, formic acid, acetic acid, oxalic acid, lactic acid, citric acid, tartaric acid or succinic acid or anhydrides of these acids.
Additionally also organic acids such as mixtures of these acids.
Process with amounts less than 0.3% by weight. The moisture level of the oil is adjusted and the oil is bleached with bleaching clay. This is followed by steam distillation of the bleached oil under vacuum to remove fatty acids. It has also been suggested to use mineral acids in place of organic acids. U.S. Patent No. granted to Watanabe et al.
No. 4113752 and British Patent No. 1359186 disclose a method for refining palm oil type oils. 0.01 to 2.0% by weight of the crude palm oil type, which is substantially free of phospholipids and in which all carotenoid compounds remain substantially heat-sensitive.
of phosphoric acid. After mixing, add activated clay,
The temperature is then raised to about 100° C. and maintained for about 5 to 30 minutes. The clay is then separated from the oil, and the oil is purified and deodorized by steam distillation using superheated steam at a temperature of 200°-270°C. The calculated ratio of phosphoric acid to bleaching clay is approximately 1:
It ranges from 0.1 to 1:60. U.S. Patent No. 3,890,5042 to Taylor relates to a method for refining crude vegetable oils and other fatty materials. The crude fatty material is heated to a temperature of about 325° to 500° under vacuum or in the presence of phosphoric acid and activated clay in an inert atmosphere. The product obtained is then filtered. OBJECTS OF THE INVENTION One of the objectives of the invention is to provide a method for refining crude vegetable oils. Another object of the present invention is to provide a method for purifying crude vegetable oils containing various impurities such as phospholipids, fungi, and trace metals. Yet another object of the present invention is to provide a process for the purification of crude vegetable oils such that economically valuable by-products can be more easily recovered. Another object of the present invention is to provide refined oil and fat products with increased stability of flavor properties. Yet another object of the present invention is to provide refined oil and fat products with increased stability against oxidation. Yet another object of the present invention is to provide a refined oil and fat product that has satisfactory low temperature test stability without the need for a separate cooling treatment step. These objects, features, and various advantages of the invention will become apparent in the detailed description of its preferred embodiments provided below. According to the present invention, in refining crude vegetable oil to provide a product with good oxidation stability, flavor stability and low temperature test stability, the following process steps are carried out, namely (a) crude oil and fat; The removal of gum by (I) combining such crude fats and oils with a small amount of water to form a mixture, () stirring this mixture, and () separating the fats and oils from the water and precipitating impurities. (b) Gummy/metal removal of the gummy fat obtained in the above process steps (a)-(); (I) Adding a small amount of suitable known gum removal to the above fat and oil. () combining the mixture with a small amount of water; () stirring the resulting mixture; and (V) freeing the fat from any remaining impurities. (c) The bleaching of the oils and fats obtained in the process steps (b) to (V) above, which have been subjected to the gum removal/metal removal treatment, is applied to (I) the above oils and fats, At least 2/1% by weight
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution such that a mixture containing 100% (i.e., not less than 0.02%) of phosphoric acid is formed; () Remaining up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in (c)-(I) above to the mixture treated in the process steps of (c)-() above; () The temperature of the mixture obtained in process steps (c)-() above is raised under vacuum to achieve the bleaching agent selected above. (V) Cool the mixture in process steps (c) to () above to a temperature that allows the vacuum to be released. and () filtering the bleached oil and fat, and then (d) steam purifying and deodorizing the bleached oil and fat obtained in the process steps (c) to () above. A method for refining the above oil and fat is provided, including each process step. According to another embodiment of the present invention, in refining crude vegetable oil to provide a product with good oxidation stability, flavor stability, and low temperature test stability, the following steps are carried out: The steps are: (a) removing the gum from the crude oil; (I) combining such crude oil with a small amount of water to form a mixture; () stirring the mixture; and () separating the oil from the water. (b) bleaching of the fat obtained in the above process steps (a)-(); (I) adding 1% by weight of at least 2/2
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution, and () the mixture is heated with vigorous stirring at a temperature suitable to permit the reaction. () Remaining up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in (b)-(I) above to the mixture treated in the process steps of (b)-() above; () The temperature of the mixture obtained in process steps (b)-() above is raised under vacuum to obtain the bleaching agent selected above. Bring the mixture to a temperature suitable for its operation, and maintain this temperature while stirring the mixture; (V) Cool the mixture of process steps (b) to () above to a temperature such that the vacuum can be broken. and () filtering the bleached oil and fat, and then (c) steam purification and deodorization of the bleached oil and fat obtained in the process steps (b) to () above. There is provided a method for refining the above fats and oils, comprising the steps. According to yet another embodiment of the present invention, in refining crude vegetable oil to provide a product with good oxidation stability, flavor stability, and low temperature test stability, the following: The process steps, namely (a) removal of gummy matter/metal content from the crude fat and oil, are carried out by () combining the above fat and oil with a small amount of a suitable known degumming agent to form a mixture; () stirring this mixture; () Combine this mixture with a small amount of water, () Stir the resulting mixture, and (V) Separate fats and oils from water to precipitate impurities, (b) Perform the steps in (a) above. - (I) Add 1% by weight of the bleaching agent for the fats and oils obtained in process step (V) to the above fats and oils in an amount of at least 2/
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution such that a mixture containing 100% (i.e., not less than 0.02%) of phosphoric acid is formed; () Remaining up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in (b)-(I) above to the mixture treated in the process steps of (b)-() above; () The temperature of the mixture obtained in process steps (b)-() above is raised under vacuum to obtain the bleaching agent selected above. Bring the mixture to a temperature suitable for its operation, and maintain this temperature while stirring the mixture; (V) Cool the mixture of process steps (b) to () above to a temperature such that the vacuum can be broken. and () filtering the bleached oil and fat, and then (c) steam purification and deodorization of the bleached oil and fat obtained in the process steps (b) to () above. There is provided a method for refining the above fats and oils, comprising the steps. According to yet another embodiment of the present invention, in refining crude vegetable oil to provide a product with good oxidation stability, flavor stability, and low temperature test stability, the following steps are carried out: Steps (a) bleaching of the crude oil and fat; (I) adding 1% by weight of at least 2/2 to the said oil;
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution, and () the mixture is heated with vigorous stirring at a temperature suitable to permit the reaction. () Remaining up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in (a) to (I) above to the mixture treated in the process steps of (a) to () above; () The temperature of the mixture obtained in process steps (a) to () above is raised under vacuum to achieve the bleaching agent selected above. (V) Cool the mixture in process steps (a) to () above to a temperature that allows the vacuum to be released; and () filtration of the bleached oil and fat, and then (b) steam purification and deodorization of the bleached oil and fat obtained in the process steps (a) to () above. There is provided a method for refining the above fats and oils, comprising the steps. Description of the invention According to the present invention, it has been revealed that an edible oil having good flavor stability, oxidation resistance stability and low temperature test stability can be obtained by a physical refining method. The invention provides, as a final product, an oil having a residual phosphorus content level of 3 ppm or less derived from the phosphoric acid used in the process according to the invention. Of course, the applicant does not wish to be bound to any one particular mechanism, but at the present stage phosphoric acid, which is added as an auxiliary in the refining process, may contain trace components in the oil, such as chlorophyll.
It reacts with phospholipids and prooxidant metals etc. during the processing process, and some difficult to explain effects that the bleaching clay would have on fats and oils if phosphoric acid were not present. It is believed to prevent After this bleaching step, the phosphorus content has no further advantageous effect, and its removal after the action of the bleaching clay does not alter the beneficial properties of the fats and oils according to the invention. I believe that there is no such thing. However, 3 ppm of phosphorus obtained in this way
The residual level up to is substantially lower than the permissible level;
Also, since it is often used as an additive in alkaline refined fats and oils, it is believed that complete removal of this refining aid is unnecessary. Residual levels of phosphorus up to 3 ppm in finished product fats and oils cannot be detected as phosphoric acid by conventional acidity measurements, and using the proven test method of AOCS Official Method No. Ca12-55. The phosphorus content is below the detection level. The phosphorus present in the form of phospholipids during bleaching does not result in fats and oils having the superior properties according to the invention. It is believed that such phosphorus compounds do not have the ability to bind heavy metals such as iron or copper that promote oxidation. In order to obtain a product oil with such excellent properties, the processing process must be such that essentially all the phosphoric acid is removed satisfactorily without allowing only the oil to be exposed to the action of bleaching agents. must be carefully controlled. Various parameters for such controlled removal of phosphoric acid have been established experimentally. Treating the fat with excess bleach will remove all of the phosphoric acid. This is believed to have the same effect as treating the oil with bleach alone, which will improve the oxidative stability of the oil. At residual phosphorus levels higher than 3 ppm, acidity becomes somewhat detectable;
And while refined fats and oils with phosphorus levels this high may have satisfactory initial properties, such fats and oils do not maintain these superior properties upon storage. In the present invention, unrefined vegetable oil is first pretreated to remove various impurities, and then purified using steam, resulting in good oxidation resistance, flavor stability, and cold test stability. It has been shown that product fats and oils can be obtained. Vegetable oils and fats are known to contain many different types of impurities, which must be removed prior to steam purification. Crude fats and oils contain some or all of the impurities listed below. These include free fatty acids, hydratable phospholipids, non-hydratable phospholipids, low-temperature insolubles (commonly referred to as "waxes"), trace metals, pigments, proteinaceous substances, and mucilage. substances, mycotoxins, pesticides, and oxidized precursors. With the exception of cottonseed oil, which contains a dark red pigment commonly referred to as "gotsushibol", which is believed to be able to be removed only by treatment with alkali, the process according to the invention can be applied to all commercially available oils. It can be applied to oils such as corn oil, soybean oil, peanut oil, sunflower oil, safflower oil, rapeseed oil, rice sugar oil, coconut oil, palm oil, palm kernel oil, and Babatus oil. These commercially known various oils and fats contain at least some of the various impurities listed above. Some, such as soybean oil and rapeseed oil, generally contain relatively high concentrations of hydratable and non-hydratable phospholipids, whereas other impurities, such as low-temperature insoluble phospholipids, The concentration of wax, etc. is at a level that does not present a removal problem. While other fats and oils, such as corn oil and sunflower oil, contain relatively high levels of "waxes" and trace metals, phospholipids usually do not contain enough to present a removal problem. Additionally, other fats and oils, such as palm oil, palm kernel oil, or coconut oil, do not exhibit concentrations of impurities that would require removal prior to bleaching and steam refining. Various physical refining methods have previously been applied to such oils with some success. However, the present invention provides a process for refining such oils to obtain a variety of advantageous properties that have hitherto not been reliably achievable. Most of the various impurities listed above cannot become useful by-products, and no attempt is generally made to recover them. However, free fatty acids and phospholipids are useful, and it is not unusual to attempt to recover them. In alkaline refining processes, only the removed free fatty acids can be recovered from the formed soap stock, and they are generally of low quality. In the present invention, the phospholipids removed are of good quality and can be used as animal feed etc. or can be further processed to recover commercial quality lentin. It is. Higher quality free fatty acids can be obtained directly in a much purer form from their steam distillation than acidic oils obtained from soap raw materials. It should be pointed out that the method described herein is effective for removing mycotoxins, such as aflatoxins, from crude oils and fats.
However, if such toxins are present, by-products may contain these impurities. Assuming that a certain crude oil contains a high concentration of low-temperature insoluble matter (wax), trace metals, and hydratable and non-hydratable phospholipids, this is the first treatment step. Crude fats and oils are subjected to gum removal treatment with water. A small amount of water, typically 1 to 5% by weight, is added and stirred with the oil. The amount of water must be sufficient to remove a significant amount of hydratable compounds.
The fats and oils are then separated by some practical method;
In this case, centrifugation or sedimentation is customary. This step can be carried out at any suitable temperature, and room temperature is often suitable. However, lower temperatures are useful for highly effective removal of compounds commonly referred to as "waxes" that do not dissolve in the oil at low temperatures. It is therefore advantageous to terminate the process at slightly lower temperatures when such "waxes" are present, and between about 5°C and about 20°C.
Temperatures up to 100% are also suitable. Water-insoluble phospholipids and trace metals, such as iron,
Another additional pretreatment step is required to remove copper, calcium, magnesium, etc. A small amount, typically less than 1% by weight, of a suitable degumming agent and water are added to the fat and oil and stirred. The degumming agent can be selected from a large number of agents known in the art, such as organic or inorganic acids or their anhydrides. Various emulsifiers and surfactants are also known to be important for this purpose. Agents currently known to be preferred are maleic acid, fumaric acid, citric acid, and phosphoric acid.
The oil and fat that has been subjected to the gum removal/metal removal treatment is then separated from the heavy phase containing residual phospholipids and residual particulate metals. The oil, which has been pretreated for bleaching by each of the process steps described above or by any other method known in the art, is then combined with a small amount of phosphoric acid in an aqueous solution. . It is preferred to use concentrated solutions to reduce the need for subsequent water removal. The amount of phosphoric acid should be sufficient to form a mixture containing at least 1% by weight of 2/100 (or more than 0.02%) phosphoric acid in the oil. Although it is possible to use higher amounts, phosphoric acid concentrations greater than about 0.2% by weight create problems with its removal, and thus the above concentration levels represent an upper limit as a practical matter. The preferred range is 1
Approximately 5/100% by weight (i.e. 0.05% by weight) to 0.1
% by weight of phosphoric acid. This mixture of fat and phosphoric acid is then stirred, advantageously with a slight increase in temperature. about 35
Temperatures between 40°C and 40°C are generally used advantageously, with the exception that at higher temperatures, usually above 40°C, it is necessary to apply a vacuum to prevent harmful oxidative effects on oil deterioration. It is thought that. At this stage, a suitable amount of bleach, such as activated bleaching clay or acid clay, is added to remove most, if not all, of the previously added phosphoric acid. The amount of bleach must be calculated to yield a final product oil with a level of up to 3 ppm residual phosphorus derived from the phosphoric acids mentioned above. The preferred bleaching agent is Filtrol
Activated bleaching clay commercially available under the trade name Filtrol 105™, sold by Co., Ltd., Inc., which was later used advantageously in several embodiments. There is. If a vacuum has not previously been applied, the system should be evacuated prior to heating and stirring the mixture to a temperature suitable for the action of the bleach used. Following the action of the bleaching agent, this bleached fat must be allowed to pass. To prevent oxidation of the oil, the vacuum should not be released until the oil has cooled sufficiently. Alternatively, the oil could be blanketed with an inert gas, such as nitrogen or carbon dioxide. The thus bleached fats and oils can then be subjected to a steam refining/deodorizing process by methods well known in the art to complete the refining process. The invention will now be described in more detail in illustrative examples. Example 1 In the UK, application number no.
Filed as No. 8212909 and October 28, 1981
High quality corn oil was extracted from corn germ by the method described in the publication published as British Patent Application No. 2074183 on the United Kingdom. This same technical disclosure was recently issued as US Pat. No. 4,341,713 claiming priority from this British patent application. The corn oil thus obtained was uncharacteristically free of phospholipids and "waxes" and was purified by the method according to the invention and, for comparison, by a conventional alkaline processing method, respectively. Some physical and chemical properties of this crude fat are listed in Table 1. 6 kg of this crude corn oil kept under a vacuum of 2 mm of mercury (2 mm Hg) absolute at 40°C.
was treated with 4/100 of 1% by weight (ie 0.04% by weight) of phosphoric acid in an 85% strength aqueous solution and stirred vigorously for 15 minutes. Next is Filtrol
Filtrol under the trade name 105®
Johns-Manville bleaching clay commercially available from Corporation Johns-Manville in an amount of 1% by weight of oil and under the trade name Filtercell®.
An amount of 2/10 of 1% of the weight of oil and fat of a supercharging material available from Co., Ltd. was added to the above-mentioned system kept under vacuum. The system was heated to 120°C and vigorous stirring was continued for an additional 20 minutes after which time the mixture was cooled to 80°C and the vacuum was broken using nitrogen gas. The bleached oil was passed through a Buchner funnel and two portions of 2.3 kg each were weighed out. One of these two parts was named sample A and was subjected to steam purification/deodorization treatment using 2% blown steam at 240°C under a vacuum of 0.2 mmHg absolute pressure for 90 minutes. Ta. The other part was designated sample B and contained 100 ppm citric acid with the addition of a small amount of citric acid in the form of a 20% strength aqueous solution, which is known to be a useful additive in alkaline refined fats and oils. A raw material for deodorizing treatment was obtained. This sample was then subjected to steam purification/deodorization treatment under the same conditions as Sample A above. These samples A
Some physical and chemical properties of and B are shown together in Table 1. A comparative sample was prepared using a conventional alkali purification method as follows. 6.1 Kg of the same crude corn oil kept at 40°C was treated with a 2.8% 16° Be' aqueous sodium hydroxide solution and stirred vigorously for 15 minutes. The oil was then heated to 65°C and stirred for an additional 15 minutes. This was followed by adding 90% of this oil per hour.
The precipitated soaps were separated by centrifugation at a centrifugal force of 1433 times the acceleration constant of gravity (9.81 m/sec. ² ) at a rate of Kg (9 Kg/Hr). In this example and the following examples, all centrifugation was performed under these conditions unless otherwise specified.
The oils and fats were then washed twice by adding 10% by weight of hot distilled water, stirring, and centrifuging each time. Next, add 100% of this oil
It was dried for 20 minutes under vacuum at 2 mmHg absolute pressure at a temperature of 20°C. This oil was mixed with 1% bleaching clay, commercially available from Filtrol Corporation under the trade name Filtrol 105®, and 1% bleaching clay, based on the weight of the oil, and Jhons® under the trade name Filtercel®. −
A surfactant commercially available from Manville Corporation was added at 0.2% by weight of the oil, and the mixture was heated at 120° C. under vacuum at 2 mm Hg absolute.
Bleached by heating to and stirring for 20 minutes. After cooling to 80° C., the oil was passed through a Buchner suction funnel and weighed and divided into two portions of 2.3 Kg each. Sample C was prepared using 1.5% blown water vapor under vacuum at an absolute pressure of 0.2 mmHg.
Deodorization was performed at 240°C for 90 minutes. A small amount of citric acid in the form of a 20% aqueous solution was added to sample D to obtain a raw material containing 100 ppm of citric acid for deodorization. This sample was then deodorized under the same conditions as Sample C. The physical and chemical properties of samples C and D are also listed in Table 1.

[Table] To evaluate the stability of each sample obtained, the oil was subjected to a color conversion test and a flavor stability test. The color conversion test consisted of storing the oil in dark conditions for 8 weeks in an unrestricted air space at ambient temperature. The chromaticity was measured according to AOCS official method Cd13b-45. Color conversion data for each sample is listed in Table 2. It is believed that the color change is the result of oxidative changes within the oil, so the peroxide value is also
Measurements were taken at the time of each chromaticity measurement according to AOCS official method Cd8-53. This data is also listed in Table 2.

[Table] The flavor stability test was conducted as follows. Samples were stored in the dark at 35°C with 10% air space above, and flavor measurements were taken by trained panel testers at 2 months, 5 months, and 12 months, respectively. It was held at Each sample is scored according to a scale of scent intensity from 1 to 9, where scale 1 indicates complete absence of scent and scale 9 indicates very strong scent. The results of these tests are listed in Table 3.

[Table] The strength of the fragrance was considerably excessive.
Example 2 A crude corn oil containing significant amounts of impurities such as free fatty acids, phospholipids, waxes, trace metals and proteinaceous materials was prepared by conventional manufacturing methods. In this method, crude oil is typically processed with a fat content of 43% to 45% and a fat content of 1.5% to 1.5% by weight.
Oil was extracted from dried corn germ with a moisture content of up to 2.0% by subjecting it to mechanical pressure in a screw press. The physical and chemical properties of this crude oil are listed in Table 4. 13.1Kg of this crude corn oil is 3.0% by weight
of distilled water and heated to 60°C. The fat was maintained at this temperature and stirred vigorously for 15 minutes. The precipitated gum was separated by centrifugation. The gummy oil obtained in this way is
It was treated with 0.2% by weight phosphoric acid in the form of an 85% strength aqueous solution. This oil was stirred vigorously for 15 minutes at 40°C. Next, add 3% by weight of distilled water and raise the temperature to 60%.
℃ and stirred for 15 minutes. This oil was then centrifuged to remove remaining gums and metal complexes. The first part of each 5.2 kg portion of the oil that has undergone this gum removal and metal removal treatment is 85
% strength aqueous solution using 0.1% by weight phosphoric acid. Next, this oil was heated to 40°C under an absolute pressure of 2
Stirred under mmHg vacuum for 15 minutes. Next, the same bleaching clay and supercharging agent as described in Example 1 above were added in amounts of 3.0% (bleaching clay) and 0.6% (supercharging material), respectively, based on the weight of the oil. The mixture was heated to 120°C and stirred for 20 minutes. The oil was cooled to 90°C, the vacuum was broken with nitrogen gas, and the oil was passed through a Buchner funnel. From the bleached oil thus obtained
Sample E and sample F in an amount of 2.3 kg were weighed. Citric acid was added to Sample F in the form of a 20% strength aqueous solution as in Example 1, thereby resulting in 100 ppm of citric acid in the raw material for deodorization.
Both samples were then subjected to a steam purification/deodorization treatment using 2.0% blown steam for 90 minutes at 240° C. under vacuum at 0.2 mm Hg absolute. The physical and chemical properties for these samples are listed in Table 4. A second portion consisting of 6.2 kg of this degummed and trace metal removed oil was reacted with a 5.4% 16° Be' caustic soda solution and stirred vigorously for 15 minutes at 40°C. The oil was then heated to 65°C and heated for 15 minutes. The soap stock formed was separated from this oil by centrifugation. The oil was then washed by adding 10% by weight of hot distilled water, stirring twice, and centrifuging each time. Next, apply this oil to an absolute pressure of 2
Dry for 30 minutes at a temperature of 100°C under a vacuum of mmHg. This oil was bleached by the addition of 2% by weight of the bleaching clay used in Example 1 above and 0.4% of superimposition agent, respectively. The mixture was heated to 120° C. under vacuum of 2 mm Hg absolute and stirred for 20 minutes. The mixture was then cooled to 90°C, the vacuum was broken with nitrogen gas, and the oil was filtered using a Buchner suction funnel. Samples G and H, each weighing 2.3 kg, were weighed from the oil thus obtained. Citric acid was added to sample H in the form of a 20% strength aqueous solution as in Example 1, thereby adding
A citric acid concentration of 100 ppm was achieved. Both samples were then deodorized for 90 minutes at 240° C. using 2% blown steam under vacuum at 0.2 mm Hg absolute. Table 4 summarizes the physical and chemical properties of these samples.

[Table] According to the method used in Example 1 above, each sample obtained as described above was subjected to a color conversion test and a flavor stability test. The obtained data are summarized in Tables 5 and 6.

【table】

[Table] was considerably excessive.
Example 3 2260 kg of compressed crude corn oil produced by conventional manufacturing methods was placed in a stainless steel plate container equipped with two propeller agitators. 113 Kg of water, equivalent to 5% by weight, is added to this oil and the mixture is kept at ambient temperature (approximately 27°C) for 30 minutes.
Stirring was performed at a rotation speed of 250 rpm. Gum that precipitates
Separation was carried out in a Westfaria® centrifuge operating at a rotation speed of 7800 rpm at an oil flow rate of 4.4 Kg/min. The resulting degummed oil was degassed and dried under vacuum at 80 mm Hg absolute at 40° C. with vigorous stirring for 70 minutes. To this oil was added 2.06 Kg of food grade phosphoric acid corresponding to 0.1% by weight in the form of an 85% strength aqueous solution, and the mixture was stirred for a further 30 minutes under vacuum. A 250 mm portion of this oil was pumped into a slurry tank where it was mixed with 62 Kg of bleaching clay (Filtrol 105 as mentioned in Example 1 above) corresponding to 3% of the total weight of the oil. and 12.5 Kg of super-adjuvant (commercially available from Jhons Manville Corporation under the trade name Hyflo Superzel®) corresponding to 0.6% based on the total weight of the oil. The mixture in the slurry tank was stirred vigorously for 5 minutes and then returned to the original container still under vacuum. Add this mixture to 120
heated to 30 °C and at a rotation speed of 100 rpm.
Stir for a minute. This mixture was then cooled to 60°C and
Then, it was maintained under reduced pressure of 100 mmHg absolute until the filtration was completed. The filter press was then blown with nitrogen gas to recover excess oil. To prepare samples with and without citric acid, citric acid in the form of a 20% aqueous solution was added to a certain amount of this oil, and this was added to sample J.
Name it. Citric acid was added at a rate of 1 ml/min in the final stage at a ratio of 50 ppm to the amount of oil. The remaining oil was not treated with citric acid and was designated Sample K. Both samples were processed in a continuous deodorizer pilot plant at a flow rate of 274 Kg/hr and an absolute pressure of 1-2 mm.
Using 3% blown water vapor under Hg vacuum
It was subjected to steam purification/deodorization treatment at a temperature of 227°C. The physical and chemical properties of these citric acid treated and non-citric acid treated oil samples are listed in Table 7. The color conversion test and peroxide value values for oils obtained in the same manner as described in Example 1 above are given in Table 8, and the flavor stability test data are given in Table 9.
Listed in the table.

【table】

【table】

EXAMPLE 4 A typical sample of crude soybean oil was purified by the method according to the invention and for comparison by a conventional alkaline refining process. Some physical and chemical properties of this oil were measured at each stage of both these refining processes and are listed in Table 10. 14Kg of this crude soybean oil was placed in a glass container at 40℃.
Then 3.0 weight percent distilled water was added and the oil was vigorously stirred for 20 minutes. The temperature was increased to 60°C and gentler stirring was continued for an additional 20 minutes. The oil was then centrifuged to separate the hydrated phospholipids. The oil thus obtained is treated with 0.2% by weight phosphoric acid in the form of an 85% strength aqueous solution,
The mixture was then vigorously stirred for 15 minutes at 40°C under a nitrogen gas atmosphere. Distilled water in an amount of 3 weight percent was then added to this oil. temperature 60
℃ and continued stirring at a slower rate for an additional 20 minutes. The oil was then centrifuged under the same conditions as above to separate the remaining phospholipids and gums from the oil. A 5.3 Kg portion of this double degummed oil was treated with 0.03% phosphoric acid in an 85% strength aqueous solution and heated at 40°C under vacuum at an absolute pressure of 2 mmHg.
The mixture was stirred for 15 minutes. Next, with the product name Filtrol 105 (registered trademark)
Bleaching clay commercially available from Filtrol Corporation, Johns-Manville under the trade name FILTERCEL® at 1% oil flow rate.
A filter aid commercially available from Co., Ltd. was added in an amount of 0.2% with respect to the oil flow rate, and the mixture was heated to 120° C. and vigorously stirred, still under vacuum. 20 such continuous processing
After a period of one minute, the mixture was cooled to 80°C, the vacuum was broken with nitrogen gas, and the oil was filtered through a Buchner suction funnel. A small amount of citric acid in the form of a 15% strength aqueous solution is added so that there is 100 ppm of citric acid in the bleached oil, and the oil is then brought to a pressure of 0.2 mm absolute.
Using 1.7% blown water vapor under Hg vacuum
It was subjected to steam purification/deodorization treatment at 240°C for 90 minutes. The oil thus obtained was named Sample L. A sample for comparison was prepared using a conventional alkali purification method as follows. 6.4 Kg of the same twice degummed oil maintained at 40°C was treated with 4.56% of 16° Be' caustic soda solution and stirred vigorously for 15 minutes under nitrogen gas atmosphere. The temperature was increased to 65°C and gentler agitation was continued for an additional 15 minutes. This oil was then centrifuged to separate the precipitated soaps. Following this, the oil was washed twice by adding 10% by weight of hot distilled water, stirring, and centrifuging each time.
This oil was then vacuumed at an absolute pressure of 2 mmHg.
It was dried for 30 minutes at a temperature of 105°C. Bleach by adding to this oil 1.0 weight percent of the same bleaching clay and 0.2 weight percent of the filter aid used previously and heating the mixture to 120° C. and stirring for 20 minutes under 2 mm Hg absolute pressure. did. After cooling to 80°C, the oil was filtered in a Buchner suction funnel. A small amount of citric acid in the form of a 15% aqueous solution was added so that the concentration of citric acid in the bleached oil was 100 ppm.
Next, this oil was heated to 1.5 mm under a vacuum with an absolute pressure of 0.2 mmHg.
Deodorization treatment was carried out at 250° C. for 90 minutes using blown steam of 50%. The oil obtained in this way was used as sample M.
It was named.

Table: Each sample obtained as described above was then tested for flavor stability. For each sample, 10% on top
The samples, each exposed to illumination conditions, were sealed in clear 8 oz. glass bottles with an air space of Stored for 3 weeks. Samples stored in dark storage conditions were kept for 6 months at a constant temperature of 35°C in a cabinet sealed against light. Flavor ratings were performed by a trained panel of examiners on a rating scale of 1 to 9 according to the method described in Example 1 above. Results are reported in Table 11.

【table】

[Table] was considerably excessive.
Example 5 Commercial Canadian rapeseed oil is made from several types of rapeseed oil, typically with low erucic acid and glucosinolate contents. This oil is commercially available as a water degummed crude product and contains a maximum of 200 ppm residual phosphorus and not more than 5.0% erucic acid. One sample of this oil was purified in the laboratory using the method according to the invention as described below. Another sample was prepared using a conventional alkaline purification process for comparison. Some physical and chemical properties of this commercially available oil are listed in Table 12. Sample 10 of this Canadian commercial grade crude rapeseed oil
Kg was placed in a metal container. An amount of maleic acid corresponding to 0.02% of the weight of the oil was added in the form of an aqueous solution, keeping the temperature constant at 25°C, and the mixture was
Stir for 10 minutes. Steam was added in an amount of 3% based on the weight of the oil, and the mixture was stirred for a further 20 minutes. The mixture was then centrifuged to remove the hydrated phospholipids from the oil. 3.3 Kg of rapeseed oil thus degummed was bleached in accordance with the further teachings of the present invention. The oil is maintained at 40°C under a vacuum of 2 mmHg absolute and this is in the form of 85% concentration, relative to the weight of the oil.
Treated with 0.1% phosphoric acid and stirred vigorously for 10 minutes. Next, 3% by weight of oil bleaching clay (commercially available from Filtrol Corporation under the trade name Filtrol 105®) and 0.6% by weight of oil filter aid (Filtercell®) Trademark) product name Johns−
(commercially available from Manville Corporation) was added to the vacuumed system. The system was heated to 120°C with vigorous stirring. After 20 minutes at this temperature, the mixture was cooled to 80°C, stirring was stopped, and the vacuum was broken with nitrogen gas. The bleached oil was filtered through a Buchner suction funnel. 2.4Kg of bleached oil thus obtained
was then subjected to steam purification/deodorization treatment. The bleached oil was first treated with 50 ppm citric acid added in the form of a 20% strength aqueous solution. This oil was then steam purified/deodorized in 5 flasks for 90 minutes at 240 DEG C. using 2% blown steam under a vacuum of 0.2 mm Hg absolute. The rapeseed oil thus physically refined was named Sample N. Table 12 shows some of the physical and chemical properties of this oil measured at various stages of the process. A sample for comparison was treated as follows using a conventional alkali purification treatment method. of rapeseed oil degummed using maleic acid as described above.
7.5 Kg were treated with 1.3% of 14° Be′ caustic soda solution and stirred vigorously for 15 minutes at 25°C. The temperature was then increased to 65°C and the oil was gently stirred further. The precipitated soaps were then separated from the oil by centrifugation. The oil was then washed twice by adding 10% by weight of hot water and mixing, and each time separating the water by centrifugation. Following this, the oil was dried under vacuum at 2 mm Hg absolute for 15 minutes at 60°C. The oil treated with alkali in this way
3.6 kg of bleaching clay (under the trade name Filtrol 105®) in an amount of 2% by weight of oil.
Commercially available from Filtrol Corporation]
and a filter aid [under the trade name Filtercell®] in an amount of 0.4% by weight of the oil.
Johns-Manville Corporation). This mixture was then heated under vacuum at an absolute pressure of 2 mmHg at 120 °C.
℃ for 20 minutes. The mixture was then cooled to 80°C, the vacuum was broken with nitrogen gas, and the oil was filtered in a Buchner suction funnel. Weigh out a 2.4 kg sample of this oil and put 20 kg in it.
50 ppm citric acid was added in the form of a % strength aqueous solution. 1.5% of this oil under a vacuum of absolute pressure 0.2mmHg.
Deodorization treatment was carried out for 90 minutes at 240° C. using blown steam of 10%. The alkali-treated oil thus produced was named Sample O. Some physical and chemical properties of this oil at various stages of the processing process are shown in Table 12, along with those of the oil itself.

【table】

[Table] In order to evaluate the stability of the rapeseed oil thus produced, these samples N and O were tested in a flavor stability test. The oils were sealed in clear 8 oz. glass bottles with 10% air space above and stored and aged under light and dark conditions, respectively. The illuminated samples were stored for three weeks at a constant temperature of 35 DEG C. in a lighting cabinet with a continuous light exposure device equivalent to 65 feet of candlelight. Samples stored in the dark were kept for 8 weeks at a constant temperature of 30°C in a cabinet sealed against light. Flavor evaluation was performed by a trained panel of examiners. Each sample is scored for its flavor intensity on a scale of 1 to 9, where a score of 1 means completely no flavor;
An evaluation value of 9 represents the strongest flavor. The results obtained are shown in Table 13.

[Table] Example 6 A sample of commercially available crude groundnut oil was divided into two parts, one of which was purified by the method according to the invention and the other by a conventional alkaline refining method for comparison. . Some physical and chemical properties of the crude oils and fats and those of samples obtained at various stages of each refining treatment method are described in Section 14.
Listed in the table. A 10 Kg sample of crude groundnut oil was mixed with 2% distilled water based on the weight of the oil and stirred vigorously for 30 minutes at a concentration of 25°C. The oil was then centrifuged to separate the hydrated phospholipids. In this way, 2.8
Kg was treated with 0.02% phosphoric acid by weight of this oil in the form of an 85% strength aqueous solution and stirred vigorously for 15 minutes at a temperature of 40° C. under atmospheric pressure. Then the filtroll described in the previous examples
105 bleaching clay was added at 0.5% by weight of the oil and Filter Cell filter aid was also added at 0.1% by weight of the oil, and the temperature was increased to 110°C and the mixture was subjected to a pressure of 2 mmHg absolute. Stir under vacuum. After stirring vigorously for 20 minutes under these conditions, the mixture was cooled to 90°C,
The vacuum was broken with nitrogen gas and the oil was filtered in a Buchner suction funnel. A 2.4 Kg sample of this bleached oil was treated with 30 ppm citric acid added in the form of a 20% strength aqueous solution, and the oil was then blown with 2% citric acid under a vacuum of 2 mmHg absolute. It was subjected to a steam purification/deodorization treatment at 240° C. for 90 minutes using mixed steam. The oil thus obtained was named Sample P. A sample for comparison was prepared using a conventional alkali purification method as follows. 2.8Kg of oil from which gums have been removed using water in advance is 1.2Kg of oil.
% of 14° Be' caustic soda solution and stirred vigorously for 15 minutes at 25°C. The temperature was then increased to 65°C and the oil was gently stirred for an additional 15 minutes. This oil was centrifuged to separate the precipitated soaps. Following this, the oil was washed twice with an amount of 10% by weight of hot distilled water and separated each time by centrifugation. Finally, apply this oil to an absolute pressure of 2 mmHg.
It was dried for 15 minutes at a temperature of 60° C. under a vacuum of 50°C. To bleach this oil, use Filtrol 105 bleach.
This was carried out by adding 0.5% and 0.1% filter aid of filter cell and heating the mixture to 110° C. under vacuum of 2 mm Hg absolute and stirring for 20 minutes. After the mixture was cooled to 90° C., the vacuum was broken with nitrogen gas and the oil was filtered in a Buchner suction funnel. A 2.4 Kg sample of this bleached oil was treated with 30 ppm citric acid added as a 20% strength aqueous solution and 1.5 kg under vacuum at an absolute pressure of 0.2 mm Hg.
Deodorization treatment was carried out at 240° C. for 60 minutes using blown steam of 50%. The oil thus obtained was named Sample R.

[Table] Both samples were tested for color conversion and peroxide gain. The color conversion test consisted of storage for 6 weeks in the dark at 25° C. under unrestricted headspace conditions. These color conversion tests and peroxide measurement tests were conducted using AOCS official method Cd13b-45 and AOCS official method Cd8, respectively.
-53. The results obtained are shown in Table 15.

[Table] Example 7 Commercially available crude, unaltered soybean oil has typically already been treated to remove gum with water. The residual phospholipid content of such oils is sufficiently low that they can be purified by the process according to the invention without any additional pretreatment. Some physicochemical properties of this crude soybean oil and those of samples obtained at various stages of each processing method are listed in Table 16. A sample of such commercially available oil was divided into two parts, one of which was purified by the method according to the invention and the other by a conventional alkaline refining process for comparison. A 3 Kg sample of crude safflower oil was treated with 0.08% phosphoric acid added in the form of an 85% strength aqueous solution and 25
Stirred in air at ℃ for 10 minutes. 2% by weight of oil Filtrol 105 bleach and also 0.4% by weight of oil Filtercel filter aid (these have been previously described) are then added and the mixture is vacuumed to 2 mmHg absolute pressure. The mixture was heated to 110°C while stirring vigorously. After continuing such treatment for 20 minutes, the mixture was cooled to 80° C., the vacuum was broken with nitrogen gas, and the oil was filtered in a Buchner suction funnel. A 2.4 Kg sample of the oil so bleached was weighed out and added in the form of a 20% strength aqueous solution.
Treated with 30 ppm citric acid. Following this, the oil was reduced to 2.0% under vacuum at an absolute pressure of 0.2 mmHg.
Steam purification/deodorization treatment was performed at 240°C for 90 minutes using blown steam. The oil thus obtained was named Sample S. A comparative sample was prepared using a conventional alkaline purification method as follows. 4.7 of crude beanflower oil
Kg of 14° Be′ 4.0% caustic soda solution and stirred vigorously for 15 minutes at 25°C. The temperature was then increased to 65°C and milder stirring continued for an additional 15 minutes. The oil was then centrifuged to remove soaps. Following this
The oil was washed twice with 10 weight percent hot distilled water and centrifuged each time. After this second wash, the oil is heated to an absolute pressure of 2
Dry for 15 minutes at a temperature of 60°C under a vacuum of mmHg. The oil was bleached by adding 1.5% Filtrol 105 bleaching clay to the weight of the oil and 0.3% Filtercel filter aid to the weight of the oil;
The mixture was then heated to 110° C. for 20 minutes under vacuum. 80% of this mixture
After cooling to 0.degree. C., the vacuum was broken with nitrogen gas and the oil was filtered in a Buchner suction funnel. By adding a small amount of citric acid as a 20% aqueous solution, the citric acid concentration in the bleached oil is 30ppm.
I made it so that A 2.4 Kg sample of this oil was then deodorized for 60 minutes at 240° C. using 1.5% blown steam under a vacuum of 0.2 mm Hg absolute.
The oil thus obtained was named Sample T.

Table: Both samples were then tested for color conversion tests and peroxide measurements using the methods previously described. The results obtained are shown in Table 17.

[Table] Other features, advantages, and various embodiments of the present invention will be apparent to those skilled in the art after reading the foregoing description of the specification. . These specific embodiments are intended to be included within the claimed subject matter unless otherwise specified. Further, although specific embodiments of the present invention have been described in detail above, various modifications and modifications of these embodiments may depart from the technical scope of the description and claims of this specification. Needless to say, it is possible to achieve this without any problems.

Claims (1)

[Claims] 1. In refining crude vegetable oils and fats to provide products with good oxidation stability, flavor stability, and low temperature test stability, the following process steps:
That is, (a) removing the gummy substance from crude fats and oils, (I) making a mixture by combining such crude fats and oils with a small amount of water, () stirring this mixture, and () separating the fats and oils from water. (b) Gummy/metal removal of the gummy fat obtained in the above process steps (a) to () is carried out by precipitating impurities; (I) a small amount is added to the above fat combining suitable known degumming agents to form a mixture, () stirring this mixture, () combining a small amount of water with this mixture, () stirring the resulting mixture, and () stirring the mixture; ) The bleaching of the fats and oils obtained in the process steps (B) to (V) above, which have undergone the process of removing gum and metals, is carried out by separating the fats and oils from the remaining impurities. I) Add 1% by weight of at least 2/
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution such that a mixture containing 100% (i.e., not less than 0.02%) of phosphoric acid is formed; () this mixture is maintained at a suitable temperature to permit reaction while stirring vigorously; () The mixture treated in the process steps (c)-() above has a residual level of up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in (c)-(I) above. Combine the bleaching agents in acceptable proportions and () raise the temperature of the mixture obtained in process steps (c)-() above under vacuum to the effect of the bleaching agent selected above. (V) cooling the temperature of the mixture of process steps (c) to () above to a temperature such that the vacuum can be broken; and () filtering the bleached fat and oil, and then (d) steam purification and deodorization of the bleached fat and oil obtained in the process steps (c) to () above. A method for refining the above-mentioned fats and oils. 2. A method according to claim 1, wherein each of the process steps in (a) is carried out at a temperature of 5°C to 20°C. 3. A process according to claim 1, wherein the bleaching step is carried out at a temperature between 90°C and 120°C. 4. The amount of phosphoric acid added in the bleaching step is sufficient to form a mixture containing from 2/100 of 1% (i.e. 0.02%) to 2/10% by weight of phosphoric acid. Method according to Section 1. 5 The amount of phosphoric acid added in the bleaching process ranges from 3/100 of 1% by weight (i.e. 0.03%) to 1/10% by weight.
A process according to claim 1, which is sufficient to form a mixture containing up to (i.e. 0.1%) phosphoric acid. 6. In refining crude vegetable oils and fats to provide products with good oxidation stability, flavor stability, and low temperature test stability, the following process steps:
That is, (a) removing the gummy substance from crude fats and oils, (I) making a mixture by combining such crude fats and oils with a small amount of water, () stirring this mixture, and () separating the fats and oils from water. (b) Bleaching of the fats and oils obtained in the process steps (a) to () above is carried out by precipitating impurities; (I) adding 1% by weight of at least 2/2
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution such that a mixture containing 100% (i.e., not less than 0.02%) of phosphoric acid is formed; () this mixture is maintained at a suitable temperature to permit reaction while stirring vigorously; () The mixture treated in the process step (b)-() above shall have a residual level of up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in (b)-(I) above. () The temperature of the mixture obtained in process steps (b)-() above is raised under vacuum to effect the action of the bleach selected above. to the appropriate temperature,
and maintaining this temperature while stirring the mixture; (V) cooling the mixture of process steps (b) to () above to a temperature such that the vacuum can be broken; and () bleaching the mixture. The process steps of (d) steam refining and deodorizing the bleached fats and oils obtained in the process steps (b) to () above are carried out by filtering the oils and fats obtained. Purification method. 7. A method according to claim 6, wherein each of the process steps in (a) is carried out at a temperature of 5°C to 20°C. 8. Process according to claim 6, wherein the bleaching step is carried out at a temperature between 90°C and 120°C. 9. Claim No. 9, wherein the amount of phosphoric acid added in the bleaching step is sufficient to form a mixture containing from 2/100 of 1% (i.e. 0.02%) to 2/10% by weight of phosphoric acid. Method according to Section 6. 10 The amount of phosphoric acid added in the bleaching process is 1
3/100 (i.e. 0.03%) to 1/10% by weight
7. A process according to claim 6, which is sufficient to form a mixture containing up to (i.e. 0.1%) phosphoric acid. 11 In refining crude vegetable oils and fats in order to provide products with good oxidation resistance, flavor stability, and low temperature test stability, the following process steps are carried out: (a) Gum of this crude oil and fat. Degumming/metal removal is carried out by: (I) combining the above oil and fat with a small amount of a suitable known degumming agent to form a mixture; () stirring this mixture; and () incorporating a small amount of water into this mixture. () Stirring the resulting mixture; (V) Separating fats and oils from water to precipitate impurities; (I) To the above oil and fat, 1% by weight of at least 2/2
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution, and () the mixture is heated with vigorous stirring at a temperature suitable to permit the reaction. () Remaining up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in (b)-(I) above to the mixture treated in the process steps of (b)-() above; () The temperature of the mixture obtained in process steps (b)-() above is raised under vacuum to obtain the bleaching agent selected above. Bring the mixture to a temperature suitable for its operation, and maintain this temperature while stirring the mixture; (V) Cool the mixture of process steps (b) to () above to a temperature such that the vacuum can be broken. and () filtering the bleached oil and fat, and then (d) steam purification and deodorization of the bleached oil and fat obtained in the process steps (b) to () above. The method for refining fats and oils as described above, comprising the steps. 12 Each of the process steps in (a) above is carried out at a temperature of 5°C to 20°C.
Claim 1 carried out at temperatures up to
Method according to Section 1. 13. Process according to claim 11, wherein the bleaching step is carried out at a temperature between 90°C and 120°C. 14 The amount of phosphoric acid added in the bleaching process is 1
2/100 (i.e. 0.02%) to 2/10% by weight
12. A method according to claim 11, which is sufficient to form a mixture comprising up to phosphoric acid. 15 The amount of phosphoric acid added in the bleaching process is 1
3/100 (i.e. 0.03%) to 1/10% by weight
12. A process according to claim 11, which is sufficient to form a mixture containing up to (i.e. 0.1%) phosphoric acid. 16 In refining crude vegetable oils and fats to provide products with good oxidation stability, flavor stability, and low temperature test stability, the following process steps are carried out: (a) bleaching of the crude oils and fats; (I) 1% by weight of at least 2/
100% (i.e., not less than 0.02%) of phosphoric acid are combined in the form of an aqueous solution such that a mixture containing 100% (i.e., not less than 0.02%) of phosphoric acid is formed; () this mixture is maintained at a suitable temperature to permit reaction while stirring vigorously; () Permit residual levels of up to 3 ppm of phosphorus in the final product derived from the phosphoric acid added in steps (a) to (I) above to the mixture treated in the process steps of (a) to () above. () The temperature of the mixture obtained in process steps (a) to () above is raised under vacuum until it is suitable for the action of the bleach selected above. (V) cooling the temperature of the mixture of process steps (a) to () above to a temperature such that the vacuum can be broken; () carried out by filtering the bleached fat and oil, and (b) including steam purification and deodorization of the bleached fat and oil obtained in the process steps (a) to () above. A method for refining the above fats and oils. 17. Process according to claim 16, wherein the bleaching step is carried out at a temperature between 90°C and 120°C. 18 The amount of phosphoric acid added in the bleaching process is 1
2/100 (i.e. 0.02%) to 2/10% by weight
17. A process according to claim 16, which is sufficient to form a mixture comprising up to phosphoric acid. 19 The amount of phosphoric acid added in the bleaching process is 1
3/100 (i.e. 0.03%) to 1/10% by weight
17. A process according to claim 16, which is sufficient to form a mixture containing up to (i.e. 0.1%) phosphoric acid.