HU198529B - Process for regaining of fat or oil of animal or plant origin from watery dispersions containing protein - Google Patents

Abstract

The present invention relates to a method of animal or plant origin fat or oil to extract water, protein, fat or oil and optionally fine-grained solid mixtures containing material. Fat or oil from these systems is the emulsion breakdown and phases of gravity or spin by separation according to the invention in such a manner to recover to the mixture based on its weight 0.05% to 0.5%, preferably 0.1-0.25% acid, preferably organic acid and 0.05-0.25% sodium salt are added and the mixture is pressurized for at least 3 minutes at least Keep at 110 ° C in this manner the phases of the mixture containing the broken emulsion by settling or separated by centrifugation in a known manner, and separating the fat or oil phase it.

Description

The present invention relates to a process for recovering animal or vegetable fat or oil from mixtures comprising water, protein, fat or oil and optionally a fine particulate matter. The process of the present invention can recover fat or oil from aqueous systems in which it forms a stable emulsion with water and hydrophilic components.

As is known, in the processing of fat-containing or oil-containing materials of vegetable or animal origin, particularly in the food industry, aqueous dispersions containing significant amounts of fat or oil are formed as by-products or waste rock. These include cooking juices, greasy wastewater, grease residues and sludges, oil residues from the processing of vegetable oils (oil sludges) and waste oils from the vegetable oil industry. A common feature of such materials is that they form a stable emulsion with a substantial amount of water in the fat or oil in the presence of protein compounds. These dispersed systems often contain, in addition to the aforementioned components, finely divided, sometimes colloidal, solids, such as bone fragments, sunflower skins, sand or other inorganic materials. Fat or oil can not be extracted from such systems by saline fat recovery procedures.

According to one known and industrially used method, a liquid containing fatty substances (fat or oil) is heated to extract the fat or oil and separated by lighter fatty material from the heavier components of the element by means of a high-speed centrifuge. However, this procedure does not work if the water / fat / fat mixture has to be separated. The three substances are bound together in such a stable manner that the liquids treated in this way leave the centrifuge unchanged without any separation of their fat or oil content as separate phases.

For similar reasons, known emptying processes, in which the system of components to be separated is stored in settling tanks for an extended period of time, are ineffective. The problem was not solved by the use of additives that increase the specific gravity, such as salt or salt water.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for recovering animal or vegetable fat or oil from proteinaceous aqueous dispersions by solving said problem.

In our studies, it has been found that the breakdown of the water-protein-fat emulsion mixture can be exploited by starting the reaction between the acids and the hydrophilic groups of the protein in stable emulsions and significantly accelerating at temperatures above 100 ° C. As a result of this reaction, the proteins are separated from the fatty substances and, due to their higher specific weights, enter the aqueous phase. However, phase separation must be promoted by increasing the specific gravity to allow the process to proceed in an industrially acceptable manner.

On the basis of this discovery, the animal or vegetable fat or oil according to the present invention is obtained from mixtures of water, protein, fat or oil and optionally a fine particulate by breaking the emulsion and separating the phases by gravity or centrifugation 0.05-0.5%, preferably 0.1-0.25% of acid, preferably organic acid and 0.05-0.25% of common salt are added and the mixture is pressurized to at least 110 ° C for at least 3 minutes, the phases of the emulsion blend thus separated are separated by road construction or centrifugation in a known manner and the fat or oil phase is separated.

As the acid, any inorganic or organic acid used in industrial, especially food processing, technologies is suitable for carrying out the process of the invention. For example, sulfuric acid may be used, but preferably an organic acid such as acetic acid, formic acid, lactic acid or propionic acid is used.

Preferably, said amount of table salt is ground to a powder to increase the specific gravity. The fine-grained table salt also accelerates the deposition of colloidal or suspended solids.

After addition of the acid and the common salt, the mixture was heated to above 110 ° C. The upper limit for heating is determined by the requirements of practical expediency. In most cases, the reaction temperature is about 110-115 ° C, although the temperature of the mixture can be raised higher. The heating time is also determined by practical conditions. Preferably, the system is maintained at a temperature above 110 ° C for about 5 to 10 minutes.

The heating is carried out in a pressure vessel and, after this time, the overpressure is removed. The phases of the mixture can then be separated by any known means and means. A centrifuge, such as a fat separator, is preferably used to separate the fat or oil, but can also be easily separated by settling, whereupon the fibrous or oily phases are usually sufficiently separated from the aqueous phase within 1 hour and up to a couple of tin.

The process according to the invention is advantageous for the treatment of various aqueous and / or fat dispersions, in particular emulsions from the food industry, from which the fat or oil must be removed or its fat or oil content must be reduced for further utilization. The recovered fat or oil is of significant value and can be used for industrial or animal feed purposes.

The most important advantage of the invention is that it is very simple to implement and therefore easy to implement in industrial applications where the handling and processing of proteinaceous aqueous and fatty oil dispersions have not been sufficiently solved.

The invention is illustrated by the following examples.

Example 1

1000 kg of 15% fat meat meat waste water was added to a pressure cooker and 2 liters of acetic acid and 2 kg of ground peanut salt were added.

The appliance will be closed and the heating will be added. The material warms to 110 ° C in about 10 minutes. After holding at this temperature for 5 minutes, the overpressure is removed and the liquid is pumped continuously into a grease separator (centrifuge). The separator separates the fat, which is easily separated from the water / protein slurry mixture. The latter can be neutralized by conventional wastewater treatment technology, chemical or microbiological.

The amount of fat recovered is 130 kg.

The cooking apparatus described in Example 1 was charged with 1000 kg of vegetable oil oil slurry containing 70% by weight of oil. To the emulsion is added 2.5 liters of propionic acid and 2.5 kg of powdered common salt. After carrying out the operations mentioned in Example 1, 650 kg of oil are obtained.

Example 3

1000 liters of bone juice from the slaughterhouse waste bones cooking, containing 5% by weight of 20 fat, should be degreased. Bone juice was processed as in Example 1, except that 2 liters of formic acid and 2 kg of common salt were added this time to break up the emulsion. We extract 40 kg of fat from it.

Example 4 25

1000 kg of 3% fat dairy wastewater was charged to a cooking apparatus according to Example 1 and 2 liters of lactic acid and 2 kg of powdered common salt were added. Heat and hold for 5 minutes at 112 ° C and transfer to a settling tank. After 1 hour, the fat phase is separated by a sharp margin. The fat is removed by pump and 25 kg of fat are recovered.

Example 5

By using known technology from slaughterhouse waste we produce fodder pulp. It has a fat content of 15% by weight. The fat content of the finished meat pulp should be reduced to 10% for feeding reasons. To 1 000 kg of meat pulp, 2 liters of sulfuric acid and 2 kg of common salt were added, followed by heating in an autoclave to 115 ° C for 5 minutes. After relieving the excess pressure, the meat pulp is transferred to a settling tank where it is allowed to stand for 1 hour. Drain 1/3 of the floated fat and re-homogenize with the rest of the meat pulp. A meat pulp with a fat content of 10% by weight is obtained and used for feeding.

Claims (3)

PATENT CLAIMS A process for recovering animal or vegetable fat or oil from mixtures containing water, protein, fat or oil and optionally a fine particulate matter by decomposing the emulsion and separating the phases by gravity or centrifugation, characterized in that 0.05% by weight is added to the mixture. -0.5%, preferably 0.1-0.25% acid, preferably organic acid, and 0.05-0.25% common salt are added and the mixture is pressurized to at least 110 ° C for at least 3 minutes. The phases of the emulsion system thus disintegrated are separated by settling or centrifugation in a known manner and the fat or oil phase is separated. 2. The process of claim 1, wherein the organic acid is acetic acid, formic acid, lactic acid or propionic acid. A process according to claim 1 or 2, characterized in that powdered common salt is added to the mixture.