Method and apparatus for life-prolonging and regenerating oil / fat

Abstract

[Problem] To provide a method and an apparatus for life-prolonging and regenerating an oil / fat. [Solution] In the apparatus and the method, an oil / fat is heated by an appropriate method to vaporize a free fatty acid, a polar compound such as a polymer and / or water contained in the oil / fat.

Description

Method and device for extending the life of oils and fats

[0001] The present invention relates to a method and an apparatus for extending and restoring the life of oils and fats, and in particular to a method for regenerating oils and fats by vaporizing and removing polar compounds and moisture contained in the oils and fats using bubbling with superheated steam or other methods.

[0002] When eating fried food purchased from a supermarket or convenience store, or when ordering fried food at a restaurant, you may notice an oily smell or feel an upset stomach after eating. This is the result of eating food cooked with deteriorated oils and fats.

[0003] Oils oxidize due to external factors such as light, air, and heat, and when oils and fats oxidize, they produce unpleasant odors, darken in color, and increase in viscosity.

[0004] Depending on the degree of oxidation, this can not only impair the flavor but can also sometimes cause food poisoning.

[0005] In this regard, the Food Sanitation Act also sets out strict standards based on acid value and peroxide value, such as requiring instant noodles (noodles treated with fats and oils) to have an "acid value (AV) not exceeding 3, or a peroxide value (POV) not exceeding 30," and for oily confectioneries (10% or more fat content) to have an "acid value (AV) not exceeding 3 and a peroxide value (POV) not exceeding 30" and "acid value (AV) not exceeding 5, or a peroxide value (POV) not exceeding 50."

[0006] The phenomenon of oil deterioration primarily refers to the state in which fatty acids, the main components of oil, combine with oxygen and oxidize when cooking with oil. When unsaturated fatty acids are oxidized, they become peroxides, and when peroxides decompose, they become free fatty acids, polymers, carbonyl compounds, and epoxides, and some of the decomposition products can be highly toxic.

[0007] The decomposition of peroxides has the property of proceeding rapidly at temperatures of 100°C or higher.

[0008] Possible indicators of the physical properties of fats and oils include acid value, peroxide value, polar compound content (PC), viscosity, color value, and odor.

[0009] In this regard, the acid value and peroxide value are widely known as indicators of the degree of oxidation of fats and oils.

[0010] When fats and oils are oxidized, they change from fats and oils to peroxides, and from the peroxides to decomposition products. The peroxide value indicates the amount of peroxides, and the acid value indicates the amount of fatty acids produced by further decomposition.

[0011] In both cases, the higher the value, the more the deterioration in the quality of the oil or fat has progressed.

[0012] Furthermore, in high-temperature oils and fats, water causes hydrolysis of unsaturated fatty acids, leading to the separation of fatty acids and other deterioration of the oil and fat, so the amount of water remaining in the oil and fat is also a value that requires attention.

[0013] At room temperature, oxidation of fats and oils occurs as a result of mild autoxidation caused by light, air, moisture, contact with metals, etc., resulting in an increase in peroxide value. Since the decomposition rate of peroxides is slow thereafter, both the peroxide value and acid value increase slowly. However, when heating to 100°C or higher is involved, such as in baking or frying, the generated peroxides are quickly decomposed, so the increase in peroxide value is not as significant, and the acid value tends to increase.

[0014] Ordinary oils are made up of a substance called triglyceride, which is one molecule of glycerol bound to three molecules of fatty acid, and the fatty acids in the triglyceride are oxidized by heat.

[0015] In particular, unsaturated fatty acids, a type of fatty acid commonly found in plant-based foods and fish, are easily oxidized, and since vegetable oils are generally used for frying, oxidation begins to occur around the oil during cooking.

[0016] Light blocking, refrigeration, and vacuum packaging are effective ways to prevent fats and oils from oxidizing, but fats and oils will continue to oxidize if they are stored indoors under fluorescent lights, or if they are stored in a refrigerator where there is a large surface area of ​​contact with air.

[0017] Therefore, when frying meat or other food ingredients (moisture) in a lighted room (light, air), using a fryer (high temperature, metal contact), the oxidation of fats and oils will progress significantly faster.

[0018] Regarding the deterioration of frying oil, although the mechanisms of oxidation at room temperature differ from those at high temperatures such as during frying, the main factors that can be considered are deterioration due to an oxidation reaction caused by contact of the hot oil surface with air (thermal oxidation), deterioration due to the reaction of water and oil and decomposition into glycerin and fatty acids (hydrolysis), and deterioration due to polymerization and decomposition at high temperatures in the absence of air (thermal polymerization and thermal decomposition).

[0019] As mentioned above, the increase in free fatty acids due to moisture in frying oil causes oxidation of the oil.

[0020] Furthermore, an increase in polymers causes stickiness, and an increase in aromatic compounds due to heat causes odor, both of which cause deterioration of the oils and fats.

[0021] These substances produced by the deterioration of fats and oils are collectively known as "polar compounds." In particular, in the case of frying oil, low-molecular-weight decomposition products, polymers, and free fatty acids act as polar compounds, causing deterioration of the frying oil in the oil tank.

[0022] The global standard for polar compounds is to capture their total amount and measure it in a number called TPM. For example, in Germany, TPM is 24%, in France, TPM 24%, in Italy, TPM 25%, and even in China and Austria, which have the most lenient standards, TPM 27% is used as the standard for assessing whether a degraded oil or fat should be disposed of.

[0023] Regarding used oil, a method has been known in the past to filter out impurities such as tempura flakes using filter paper, filtering media, metal mesh, etc.

[0024] However, since this method simply removes impurities from the oils and fats, it goes without saying that it cannot reduce the acid value or peroxide value of the oil or remove the water present in the oils and fats.

[0025] The flavor, odor, and color were not significantly improved by filtering out impurities.

[0026] In addition to filtering out impurities, there have been other methods, such as placing ceramics in the oil tank to extend the shelf life of the oil, but none of these have been shown to have any clear effect.

[0027] In this regard, Patent Document 1 below discloses an edible oil recycling device and method that regenerates rancid edible oil by pumping and releasing air that has been subjected to a predetermined physical treatment using magnetism or far infrared rays into the edible oil, but the use of air in the first place means that oxygen is present, which has the insurmountable disadvantage of unavoidable oxidation, and there is no disclosure or suggestion regarding the peroxide value of used oil. Furthermore, Non-Patent Document 1 below mentions a technology in which ultrafine nitrogen bubbles are blown into oil to expel oxygen from the oil and also suppress oxidation after opening, but the use of nitrogen causes oxygen deficiency, posing a risk to life and limb, making long-term use such as continuous operation difficult, and therefore serious issues remain regarding the extension and recycling of oil.

[0028] The oxidation of oil is caused by the generation of active substances called radicals. Once radicals are generated, they convert the unsaturated fatty acids present into radicals one after another, and the radicals then bond together to form polymers, which is thought to be the cause of the increased viscosity of used frying oil. Radicals are also thought to damage cells and DNA, leading to lifestyle-related diseases such as cancer and arteriosclerosis.

[0029] These deteriorated oils and fats are difficult to break down with human digestive enzymes, which causes the symptom known as "heavy stomach." In addition, the oxidized fatty acids are broken down into smaller molecules, which causes an "oily smell."

[0030] For these reasons, it is desirable to replace frying oil after only one use whenever possible. Also, since radicals once generated will generate a chain reaction of radicals, the current situation is that unless these radicals can be removed, the problem of deteriorated oils and fats cannot be fundamentally solved even by adding new oil.

[0031] Patent No. 4455653

[0032] https: / / www.nisshin-oilllio.com / company / news / down2.php?attach_id=1640&uid=8851

[0033] Therefore, an object of the present invention is to provide a method and an apparatus for extending and restoring the life of oils and fats, including oils and fats that have deteriorated due to use as frying oil, etc.

[0034] In order to solve the above problems, the inventor of the present invention conducted repeated research and experiments and came up with a method for vaporizing and removing free fatty acids, polar compounds, moisture, and other substances that cause deterioration of oils and fats, which are generated by hydrolysis, thermal decomposition, etc., using the following method and device.

[0035] The method and device for extending the life of fats and oils of the present invention have the following configurations. [1] A method for extending the life of fats and oils, comprising heating fats and oils by an appropriate method to vaporize at least any or all of free fatty acids, polar compounds such as polymers, and water contained in the fats and oils. [2] The method for extending the life of fats and oils described in [1], in which the fats and oils are heated by contact with superheated steam that has reached a predetermined temperature. [3] The method for extending the life of fats and oils described in [2], in which the contact between the superheated steam and the fats and oils is carried out by bubbling with the superheated steam. [4] The method for extending the life of fats and oils described in [3], in which the bubbling is carried out by the superheated steam heated to 140°C or higher. [5] The method for extending the life of fats and oils described in [3], in which the bubbling is carried out by the superheated steam heated to 180°C to 400°C. [6] The method for extending and restoring the life of fats and oils according to [3], wherein the bubbling is carried out using the superheated steam heated to 200°C to 380°C. [7] The method for extending and restoring the life of fats and oils according to any one of [3] to [6], wherein the superheated steam is formed into tiny bubbles and sprayed from a nozzle to bubble when contacted with the fats and oils. [8] The method for extending and restoring the life of fats and oils according to any one of [3] to [7], wherein the superheated steam is bubbled while the fats and oils to be treated are stirred by an appropriate method. [9] The method for extending and restoring the life of fats and oils according to [8], wherein the stirring is carried out by centrifugation.

[10] The method for extending and restoring the life of fats and oils according to any one of [1] to [9], wherein impurities contained in the fats and oils to be treated are removed by centrifugation.

[11] The method for extending and restoring the life of fats and oils according to any one of [3] to

[10] , wherein the fats and oils to be treated are mixed with superheated steam and charged into a bubbling oil tank.

[12] The method for regenerating fats and oils according to any one of [1] to

[11] , wherein the fats and oils to be treated are heated within a range of 250°C or less.

[13] The method for regenerating fats and oils according to any one of [3] to

[12] , wherein the bubbling space is maintained under positive pressure by the delivery of the superheated steam.

[14] A device for regenerating fats and oils comprising a main body having an fat inlet for introducing at least the fats and oils to be treated, and an appropriate heating means for heating the fats and oils.

[15] The life-extension and recycling device for grease and oils according to

[14] , wherein the main body is hollow and has a superheated steam inlet and an exhaust port, and the heating means is an aeration means using superheated steam taken in through the inlet arranged inside the main body.

[16] The life-extension and recycling device for grease and oils according to

[15] , wherein the aeration means includes an oil tank for storing the grease to be treated introduced through the grease inlet, and a nozzle capable of sending superheated steam introduced through the inlet as fine bubbles to the grease in the oil layer.

[17] The life-extension and recycling device for grease and oils according to

[15] , wherein the aeration means is aeration by contact between the grease to be treated introduced through the grease inlet and superheated steam bubbles taken in through a perforated plate arranged at the bottom of the oil tank for storing the grease.

[18] The life-extension and recycling device for grease and oils according to

[16] or

[17] , wherein the oil tanks are arranged in multiple stages.

[19] The life extension and recycling device for grease and oils according to any one of

[14] to

[18] , wherein the main body is equipped with a spray mechanism capable of spraying the grease and oil to be treated into the inside of the main body.

[20] The life extension and recycling device for grease and oils according to any one of

[14] to

[19] , wherein the main body is equipped with a centrifugal separation mechanism.

[21] The life extension and recycling device for grease and oils according to any one of

[15] to

[20] , wherein the main body is equipped with an integrated superheated steam generator.

[22] The life extension and recycling device for grease and oils according to any one of

[16] to

[21] , wherein the oil tank is equipped with a stirring blade or other appropriate stirring mechanism capable of stirring the grease and oil in the oil tank.

[23] The grease and oil obtained by subjecting used grease and oil to the life extension and recycling method according to any one of [1] to

[13] .

[0036] In the method for extending and restoring the life of fats and oils of the present invention, the fats and oils can be heated by bubbling with superheated steam that has reached a predetermined temperature. In this case, the bubbling can be performed with the superheated steam heated to 140°C or higher, more preferably 180°C to 400°C, and even more preferably 200°C to 380°C.

[0037] In the method for extending and restoring the life of fats and oils of the present invention, the superheated steam may be formed into tiny bubbles and injected from a nozzle to bubblingly mix with the fats and oils. Alternatively, the superheated steam may be bubbled while stirring the fats and oils to be treated by an appropriate method.

[0038] Furthermore, the method for extending and restoring the life of fats and oils of the present invention can also be configured to involve mixing the fats and oils to be treated with superheated steam and throwing them into an oil tank for bubbling.

[0039] In addition, in the method for extending and restoring the life of fats and oils of the present invention, it is desirable to heat the fats and oils to be treated at a temperature of 250°C or less.

[0040] According to the method for extending and restoring the life of fats and oils of the present invention, by bubbling superheated steam heated to a predetermined temperature into the fat and oil to be treated, polar compounds that cause deterioration and are contained in fats and oils that have been oxidized through use, can be targeted and vaporized and removed by taking advantage of the difference in boiling points between the polar compounds and other substances, thereby restoring the acid value and peroxide value of oxidized fats and oils, which was not possible with conventional methods such as filtration, and further removing the water from the deteriorated fat and oil, thereby extending and restoring the life of the fat and oil, and making it possible to significantly reduce the frequency of changing frying oil.

[0041] In addition, by using superheated steam heated to, for example, 200°C to 260°C in the method for extending the life of fats and oils of the present invention, it is possible to avoid the situation where bubbling from high-temperature superheated steam further causes hydrolysis due to the water in the fats and oils, creating an environment that is unfavorable for the regeneration of oxidized fats and oils.

[0042] Similarly, by appropriately adjusting the temperature of the superheated steam and the bubbling time so that the temperature of the oils and fats to be recycled remains within a range of 250°C or less, it becomes possible to continue to extend the life and regenerate the oxidized oils and fats in a good environment, and it also helps prevent smoke and fire in the fryer tank.

[0043] Furthermore, by forming the superheated steam into extremely small bubbles such as microbubbles or nanobubbles and bubbling them, the contact area between the superheated steam and the oil or fat to be treated can be significantly increased, thereby improving the regeneration efficiency and avoiding disadvantages such as reduced fuel consumption due to long-term aeration.

[0044] It is also possible to add a process of removing impurities contained in the used oil using a centrifuge or the like before or after the bubbling process with superheated steam, or in parallel with the bubbling process.This allows the oil to be separated into water, oil, and solids, and by extracting only the oil from this and subjecting it to a regeneration process, impurities such as burnt parts that cause blackening can be removed in advance, making it possible to regenerate highly transparent oil.

[0045] A front view showing the configuration of an oil and fat life extension regeneration device used in carrying out the present invention. A diagram showing the internal configuration of the main body of an oil and fat life extension regeneration device used in carrying out the present invention. A conceptual diagram illustrating an embodiment of the oil and fat life extension regeneration method of the present invention. A plan view of a perforated plate used in an example of the present invention. A conceptual diagram showing an embodiment of the oil and fat life extension regeneration method of the present invention equipped with a centrifugal separation mechanism. A graph showing the change in acid value in an example of the present invention.

[0046] One embodiment of the method for extending and restoring the life of fats and oils of the present invention will be described below with reference to the drawings.

[0047] FIG. 1 shows an oil life extension and regeneration device A for carrying out the method for regenerating oil life of the present invention.

[0048] The oil and fat life extension and regeneration device A comprises an approximately cylindrical main body S, a base B, and legs L, and the main body S comprises a first space for filling and discharging superheated steam for bubbling, and a second space having an oil tank T therein for storing the oil and fat to be treated and bubbling it.

[0049] Here, water vapor is normally at around 100°C, but it is possible to raise the temperature to several hundred degrees Celsius even under normal pressure, and as the volume rapidly expands above about 140°C, the oxygen concentration can be significantly reduced compared to that of a normal liquid state. In the present invention, this type of water vapor is called "superheated water vapor."

[0050] This makes it possible to dry and bake things even though it is water, and this is already widely known in a variety of fields, including drying and carbonizing waste, sterilizing food and baking ingredients, roasting coffee, and applications in home ovens and ranges.

[0051] In this embodiment, even though the superheated steam is used at a high temperature, there is no risk of the oil burning and the resulting odors being attached to the oil, whereas heating with a burner or the like can cause odors to be attached to the oil.

[0052] Furthermore, the main body S is provided with a superheated steam inlet I connected to a superheated steam generator W provided integrally or separately therewith for taking in superheated steam into the first space, and a waste oil outlet D for discharging to the outside waste oil containing polar compounds, etc. that have been vaporized and removed by the bubbling of the superheated steam.

[0053] The main body S also has an oil and fat input hopper H for inputting the oil and fat to be used for the life extension regeneration process into the oil tank T, and an exhaust port E at the upper end of the main body S for discharging the superheated steam after bubbling to the outside.

[0054] In this embodiment, the oil tank T has a three-layer structure in which, for example, the bottom surface is formed as a perforated plate P having a large number of holes with a diameter of about 0.5 to 10 mm, and the perforated plate P is stacked three times (see FIG. 2).

[0055] The fats and oils to be treated that are fed from the fat and oil feeding hopper H are poured into the top (first layer) oil tank T1, and when, for example, 15 liters have accumulated, they are poured through the overflow pipe O1 into the second layer (oil tank T2) below.When 15 liters have accumulated in the oil tank T2, they are then poured through the overflow pipe O2 into the third layer (oil tank T3).

[0056] After the final bubbling in the oil tank T3, the treated oil flows further downward through an overflow pipe O3 provided in the oil tank T3 and is sent to a primary storage tank (not shown).

[0057] The treated oil that has completed the three-stage life extension and regeneration process is returned to the original fryer through a treated oil transport pipe (not shown) by an appropriate delivery means such as a pump.

[0058] In other words, in this way, the method for extending and regenerating the life of fats and oils of the present invention can extend and regenerate the life of fats and oils without interrupting the frying process while continuing the frying operation in the fryer, making it possible to use the fryer continuously while always maintaining high quality.As a result, if the method for extending and regenerating the life of fats and oils of the present invention is started from the time new oil is added, the increase in acid value and peroxide value can be constantly suppressed from the start of frying operation, achieving the effect of avoiding the deterioration of fats and oils themselves.

[0059] Furthermore, by connecting the oil spilled from the overflow pipe O3 to the oil input hopper H of another regeneration tower, it is possible to configure the life-extension regeneration process to be performed in six stages (or even nine stages, 12 stages, etc.), thereby increasing the processing capacity and improving the processing efficiency. Alternatively, it is also possible to configure the oil tank T as only one tank, thereby miniaturizing the life-extension regeneration device.

[0060] In the method for extending and regenerating oil and fat life of the present invention, the superheated steam that has been heated to a high temperature passes through the air supply pipe and is taken into the first space in the main body S of the oil and fat life extension and regeneration device A from the superheated steam intake port I in preparation for the start of bubbling.At this time, the filled superheated steam also serves to warm up the entire oil and fat life extension and regeneration device A.

[0061] However, it is optional to first charge the fats and oils from the fat and oil charging hopper H before filling with the superheated steam, and in this case, the fats and oils to be treated can be mixed with the superheated steam and charged into the oil tank T for bubbling, thereby improving the treatment efficiency.

[0062] Furthermore, after the oil and fat are charged, a step of removing impurities contained in the used oil and fat can be added before or after the bubbling step with superheated steam in the oil tank, or in parallel with the bubbling step. Impurities can be removed by any appropriate method, such as adsorption with bleaching earth, filtration with a filter, or centrifugation using centrifugal force caused by rotation.

[0063] Specifically, for example, oils and fats being used as frying oil in a fryer (not shown) are sucked up from an oil suction pipe (not shown) by an appropriate means such as a pump and transported to an oil and fat input hopper H provided in the main body S of the oil and fat life extension and recycling device A.

[0064] Therefore, the oil to be treated that is fed from the oil / fat feeding hopper H is subjected to a centrifuge C for so-called sludge removal before being sent to the oil tank T1. A three-phase separator (liquid-liquid-solid separator) can be used as the centrifuge C, which can separate the oil to be treated containing impurities into water, oil, and solids. By extracting only the oil from this and subjecting it to a regeneration process, impurities such as burnt residue that cause darkening can be removed in advance, allowing it to be regenerated as a more transparent oil. At this time, by configuring the oil to be treated stored in the oil tank to be centrifuged while bubbling superheated steam, it is possible to simultaneously remove impurities and perform a life-extending regeneration process for the oil.

[0065] The oils and fats to be treated, from which impurities have been removed, are transported through a pre-treatment oil transport pipe to a spray M, where they are mixed with compressed superheated steam and sprayed into the second space from an oil and fat input hopper H. The atomized oils and fats to be treated are stored in an oil tank T1 disposed in the second space while exposed to superheated steam, and are then sequentially filled into oil tanks T2 and T3 via overflow pipes O1 and O2. At this time, the main body S of the oil and fat life extension and regeneration device A is filled with high-temperature, expanded superheated steam, creating a positive pressure, and the air that was inside the tower is expelled outside the tower, so that the inside of the main body S is always maintained in a substantially oxygen-free state.

[0066] The superheated steam enters the oil tank T3 through the holes in the perforated plate P3 arranged at the bottom of the oil tank T3, rises while submerged in the oil, and reaches the perforated plate P2 at the bottom of the oil tank T2. The superheated steam then enters the oil tank T2, rises through the oil, and reaches the bottom of the oil tank T1. Finally, the steam rises while submerged in the oil in the oil tank T1 and is discharged to the outside of the main body S through the exhaust port E.

[0067] At this time, polar compounds such as free fatty acids, low-molecular-weight decomposition products, and polymers contained in the oils and fats in each oil layer T are vaporized by exposure to the high-temperature superheated steam, and are eventually carried to the exhaust port E along with the superheated steam containing these compounds.

[0068] In this example, bubbling with superheated steam was performed using bubbles formed by a perforated plate, but to further increase the processing efficiency, it is also possible to form the superheated steam into extremely small bubbles such as microbubbles or nanobubbles when mixing the oil and the superheated steam, and then spray these from a nozzle into the oil tank T for the bubbling process. Alternatively, it is also possible to improve the heating efficiency by using an appropriate means such as a stirring blade or a homogenizer to stir the oil during the bubbling process.

[0069] The exhaust port E is connected to a cooling chamber (not shown) by a duct, and substances containing polar compounds, etc., which are once cooled and liquefied here, flow out of the main body S through the waste oil discharge port D and are collected as waste oil.

[0070] In this way, the remaining water in addition to the polar compounds in the oils and fats, such as free fatty acids, low-molecular-weight decomposition products, and polymers, evaporates, effectively removing the substances in the oils and fats that cause deterioration, and the oils and fats are reduced to components almost equivalent to those at the time of initial use.

[0071] Thereafter, the treated oil is fed into the oil tank of the fryer via a treated oil transport pipe (not shown) and can be reused as frying oil.

[0072] There are no particular restrictions on the oils and fats that can be treated in the method for extending and restoring the life of oils and fats of the present invention, and they may be, for example, oils and fats that have deteriorated due to oxidation after being stored for a long period of time or exposed to light or oxygen after opening, or used oils and fats such as those that have been used as frying oil.

[0073] Example 1 In this example, superheated steam heated to 230°C was bubbled through used palm oil at 160°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. As the treatment time passed, the acid value decreased as shown below.

[0074] Example 2 In this example, superheated steam heated to 200°C was bubbled through used oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. The acid value decreased as the treatment time passed, as shown below. Regarding the odor, five out of five people responded that the burnt odor weakened as the treatment time passed.

[0075] Example 3 In this example, superheated steam heated to 230°C was bubbled through used oil at 160°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. The acid value decreased as the treatment time passed, as shown below. Regarding odor, five out of five people answered that the unpleasant odor disappeared as the treatment time passed.

[0076] Example 4 In this example, superheated steam heated to 200°C was bubbled through used oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. The acid value decreased as the treatment time passed, as shown below. Regarding the odor, five out of five people answered that the odor disappeared as the treatment time passed.

[0077] Example 5 In this example, superheated steam heated to 210°C was bubbled through used oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. As a result, the acid value decreased as the treatment time passed, as shown below.

[0078] Example 6 In this example, superheated steam heated to 210°C was bubbled through used canola oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. As the treatment time progressed, the acid value decreased as shown below.

[0079] Example 7 In this example, superheated steam heated to 210°C was bubbled through used oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. As a result, the acid value decreased with the passage of treatment time as shown below.

[0080] Example 8 In this example, superheated steam heated to 210°C was bubbled through used oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. The acid value decreased as the treatment time passed, as shown below. Furthermore, there was no increase in TPM, and the value decreased after 40 minutes of treatment.

[0081] Example 9 In this example, superheated steam heated to 210°C was bubbled through used oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined intervals. The acid value decreased as the treatment time increased, as shown below. Regarding odor, measurements were performed using oil used to fry burdock before treatment. Five out of five participants reported that the burnt smell from the burdock disappeared over time. Furthermore, while deep-frying in oil with a high acid value results in a burnt color, a side dish (eggplant) fried in the oil before treatment had a burnt color and was generally sticky. However, when the oil used was oil treated with the life-extension and restoration method of the present invention for 40 minutes, the color of the fried food approached that of fresh oil, resulting in a crispy, pleasant texture.

[0082] Example 10 In this example, superheated steam heated to 210°C was bubbled through used rapeseed oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined time intervals. As a result, the acid value decreased with the passage of treatment time as shown below.

[0083] Example 11 In this example, superheated steam heated to 200°C was bubbled through used oil at 180°C, and the acid value of the oil in the oil tank T was measured at predetermined intervals. The acid value decreased as the treatment time increased, as shown below. Five out of five participants reported that the burnt smell weakened as the treatment time increased. Furthermore, when fried chicken or croquettes were fried in untreated oil, the color was burnt and the coating was sticky. However, when the oil and fat treated with the life-extension and restoration method of the present invention for 30 minutes were used, the color of the fried food approached that of the food fried in new oil, and the coating had a crispy, pleasant texture.

[0084] Example 12 In this example, superheated steam heated to 240°C was bubbled through used oil heated to 180°C, and the acid value of the oil in the oil tank T was measured at predetermined intervals. The acid value decreased with the passage of treatment time, as shown below. Five out of five participants reported that the burnt smell weakened with the passage of treatment time. Furthermore, when fried chicken in the oil before treatment, the color of the fried chicken was burnt and the batter was sticky. However, when the oil treated with the life-extension and restoration method of the present invention for 30 minutes was used, the color of the fried chicken approached that of the fried chicken in new oil, and the batter had a crispy, pleasant texture.

[0085] Example 13 In this example, superheated steam heated to 240°C was bubbled through used oil heated to 180°C, and the acid value of the oil in the oil tank T was measured at predetermined intervals. The acid value decreased with the passage of treatment time, as shown below. Ten out of ten participants responded that the taste improved as treatment time progressed, as the umami of the ingredients themselves, which had initially been masked by the bitterness, became apparent. Furthermore, when spring rolls were fried in oil before treatment, the fried product had a burnt color and the batter was sticky. However, when the oil treated with the life-extension and restoration method of the present invention for 30 minutes was used, the fried product color approached that of the product fried in new oil, and the batter had a crispy, pleasant texture.

[0086] Example 14 In this example, superheated steam heated to 240°C was bubbled through used rapeseed oil heated to 180°C, and the acid value of the oil in the oil tank T was measured at predetermined intervals. The acid value decreased as the treatment time passed, as shown below. Seven out of seven people responded that the taste improved as the treatment time passed. Furthermore, when Isobe-age was fried in oil before treatment, the color of the fried food was burnt and the batter was sticky, whereas when the oil treated with the life-extension and restoration method of the present invention for 30 minutes was used, the color of the fried food approached that of when it was fried in new oil, and the batter had a crispy, desirable texture.

[0087] The waste oil collected from the waste oil outlet D had an acid value of 4.0 or more and a TPM of 39%, indicating that the polar compounds removed by vaporization were discharged to the drain.

[0088] Furthermore, when the method for extending and restoring the life of fats and oils of the present invention, which includes a centrifugal separation process, was used, seven out of seven people responded that the fats and oils that were dark before treatment became transparent after treatment, and that improvements were observed in taste, odor, viscosity, and color value.

[0089] <Oil Life Extension Regeneration Device Operation Procedure> ■Start of work 1 Boiler switch ON 2 Control panel, control power ON 3 Electric superheated steam generator, check steam pressure Primary pressure: 5K (0.5MPa) 4 Check fryer oil temperature setting 180°C 5 Electric superheated steam generator switch ON Heater outlet temperature setting: 260°C Superheated steam is passed to the exhaust duct via a three-way valve. 6 Oil Life Extension Regeneration Towers A and B (Heating before regeneration) Regeneration tower heating piping solenoid valves open Pumps No. 1 and No. 2 send fryer oil from the first stage of the regeneration tower, and pumps No. 3 and No. 4 circulate the oil back to the fryer to heat the regeneration tower. 1st, 2nd and 3rd stage internal temperatures of the fat life extension regeneration tower are 150°C or higher. 7. Close the solenoid valve for the regeneration tower heating pipe (oil will only be supplied through the two-fluid nozzle). *Automatically opens and closes using the oil temperature sensor inside the regeneration tower. 8. Send superheated steam to fat life extension regeneration towers A and B. Heater outlet temperature setting: 260°C. 9. At the bottom of the fat life extension regeneration tower, the float switch automatically operates the No. 2 and No. 4 pumps, returning them to the fryer. ■ Work completed. 10. Stop the No. 1 and No. 3 pumps. 11. Close the superheated steam generator and primary steam valve. Heater switch OFF. 12. Stop the pumps if the No. 2 and No. 4 oil level sensors detect empty oil. 13. Turn off the control panel and control power supply.

[0090] As described above, the present invention involves bubbling superheated steam heated to a predetermined temperature through the oils and fats to be treated. Due to the difference in vaporization temperatures between polar compounds, which are substances that cause deterioration in oils and fats that have oxidized through use, and other substances, it is possible to target and vaporize and remove polar compounds. This makes it possible to restore the acid value (AV) and peroxide value (POV) of oxidized oils and fats, suppress an increase in TPM, and even remove moisture from the oils and fats, something that could not be achieved by conventional methods such as filtration. This also makes it possible to significantly reduce the frequency of oil and fat replacement. Furthermore, since the superheated steam used is heated to a moderate temperature of 200°C to 380°C, a positive pressure is created inside the regeneration tower by the expanded superheated steam, creating a substantially oxygen-free state and preventing the oxidation of the oil and fats. Furthermore, bubbling with high-temperature superheated steam causes hydrolysis by the moisture in the oil and fats, creating an environment that is unfavorable for extending the life and regeneration of oxidized oil and fats. Similarly, by appropriately adjusting the temperature of the oil to be regenerated and the bubbling time, for example, so that the temperature of the oil to be regenerated remains below 250°C, it is possible to continue regenerating oxidized oils and fats in a good environment. Therefore, if use is started from the time new oil is added, increases in the acid value, peroxide value, and TPM can be constantly suppressed from the start of frying, as if deterioration of the oil itself could be avoided. Furthermore, by forming the superheated steam into tiny bubbles and bubbling it, the contact area between the superheated steam and the oil to be treated can be greatly increased, improving regeneration efficiency and avoiding disadvantages such as reduced fuel efficiency due to long-term bubbling. In addition, since this is an environmentally friendly treatment method that does not discharge waste such as used filter media, it is extremely suitable for use as a method for extending the life of oils and fats, including deteriorated oils and fats such as used frying oil.

[0091] A Grease life extension and recycling device S Main body B Base L Leg I Superheated steam intake D Waste oil discharge port T Oil tank H Grease input hopper E Exhaust port P Perforated plate O Overflow pipe V1 Pressure valve V2 Pressure valve C Centrifuge M Spray N Nozzle W Superheated steam generator

Claims

1. A method for extending and restoring the life of fats and oils, characterized by heating fats and oils by an appropriate method and vaporizing at least any or all of the free fatty acids, polar compounds such as polymers, and water contained in the fats and oils.

2. A method for extending and restoring the life of fats and oils as described in claim 1, wherein the fats and oils are heated by contacting them with superheated steam that has reached a predetermined temperature.

3. A method for extending and restoring the life of fats and oils as described in claim 2, wherein the contact between the superheated steam and the fats and oils is carried out by bubbling the superheated steam.

4. A method for extending and restoring the life of fats and oils as described in claim 3, wherein the bubbling is performed using superheated steam heated to 140°C or higher.

5. A method for extending and restoring the life of fats and oils as described in claim 3, wherein the bubbling is performed using superheated steam heated to 180°C to 400°C.

6. A method for extending and restoring the life of fats and oils as described in claim 3, wherein the bubbling is performed using superheated steam heated to 200°C to 380°C.

7. A method for extending and restoring the life of fats and oils according to any one of claims 3 to 6, wherein the superheated steam is formed into tiny bubbles and then sprayed from a nozzle to bubblingly contact the fats and oils.

8. A method for extending and restoring the life of fats and oils according to any one of claims 3 to 7, wherein the method comprises bubbling the superheated steam while stirring the fats and oils to be treated by an appropriate method.

9. A method for extending and restoring the life of fats and oils as described in claim 8, wherein the stirring is performed by centrifugation.

10. A method for extending and restoring the life of fats and oils according to any one of claims 1 to 9, in which impurities contained in the fats and oils to be treated are removed by centrifugation.

11. A method for extending and restoring the life of fats and oils according to any one of claims 3 to 10, in which the fats and oils to be treated are mixed with superheated steam and then poured into an oil tank for bubbling.

12. A method for extending and restoring the life of fats and oils according to any one of claims 1 to 11, wherein the fats and oils to be treated are heated to a temperature of 250°C or less.

13. A method for extending and restoring the life of fats and oils according to any one of claims 3 to 12, wherein the space in which bubbling is carried out is made positively pressured by sending out the superheated steam.

14. A device for extending and recycling the life of grease, comprising a main body having at least an grease inlet for feeding the grease to be treated, and an appropriate heating means for heating the grease.

15. The oil and fat life extension and recycling device described in claim 14, wherein the main body is hollow and has an inlet and an outlet for superheated steam, and the heating means is an aeration means using superheated steam taken in from the inlet arranged inside the main body.

16. The oil life extension and regeneration device described in Claim 15, wherein the aeration means comprises an oil tank for storing the oil to be treated that is fed through the oil inlet, and a nozzle capable of sending superheated steam taken in through the intake as fine bubbles to the oil in the oil layer.

17. The oil and fat life extension and regeneration device described in Claim 15, wherein the aeration means is a device that brings the oil and fat to be treated, which is fed through the oil and fat feeding port, into contact with bubbles of superheated steam taken in through a perforated plate arranged at the bottom of an oil tank that stores the oil and fat.

18. The oil and fat life extension and recycling device according to claim 16 or 17, wherein the oil tanks are arranged in multiple stages.

19. An oil and fat life extension and recycling device as described in any one of claims 14 to 18, wherein the main body is equipped with a spray mechanism capable of spraying the oil and fat to be treated into the inside of the main body.

20. An oil and fat life extension and recycling device as described in any one of claims 14 to 19, wherein the main body is equipped with a centrifugal separation mechanism.

21. A device for extending and recycling the life of fats and oils according to any one of claims 15 to 20, wherein the main body is integrally provided with a superheated steam generator.

22. A device for extending and recycling the life of grease and oils as set forth in any one of claims 16 to 21, wherein the oil tank is provided with an appropriate stirring mechanism such as a stirring blade capable of stirring the grease and oils in the oil tank.

23. A used oil or fat obtained by subjecting the oil or fat life extension and revitalization method described in any one of claims 1 to 13.

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