JPH04370195A - Method for deacidifying oil and fat - Google Patents

Abstract

PURPOSE:To obtain a deacidifying method of oil and fat capable of suppressing production of emulsion and deacidifying in good state when oil and fat are deacidified by Jenice method. CONSTITUTION:In a method for carrying out deacidification of oils and fats using an aqueous alkali solution by Jenice method, an aqueous alkali solution to which 1.0-10.0wt.% water soluble alcohol is added is used as the aqueous alkali solution.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for deoxidizing fats and oils.

0002

[Prior Art] The main purpose of deacidification of fats and oils is to remove free fatty acids from fats and oils, but it also removes trace components such as gums, pigments, and metals, which can be used in subsequent processes such as bleaching, curing, and deodorization. This improves efficiency. That is, the quality of deacidification and refining is one of the main factors in improving the quality of fats and oils, and deacidification is an important step in the refining process of fats and oils.

[0003] Methods for deoxidizing fats and oils can be broadly classified into distillation deoxidation methods and alkaline deoxidation methods, but the alkali deoxidation method is the mainstream, as it has a large additional effect in addition to removing free fatty acids. Traditionally, alkaline deoxidation methods have mainly involved deoxidation using continuous centrifugation, but recently the Zenith method, which is cheaper than this method and causes less loss of neutral oil, has come into use. .

The Zenith process consists of three semi-continuous steps: a phosphoric acid treatment step, a deacidification step and a bleaching step. Phosphoric acid treatment process: A process in which gums, etc. are removed by adding phosphoric acid to fats and oils under vacuum. Deacidification step: At the center of the Zenith method, fats and oils are introduced from the bottom of the neutralization column filled with an aqueous sodium hydroxide solution, and the introduced fats and oils are made into oil droplets of 0.5 to 3.0 mm and placed in an aqueous sodium hydroxide solution. The process of removing free fatty acids by increasing the

[0005] Bleaching process: Removes soap content remaining in fats and oils,
A process to improve the color tone of oils and fats using activated clay. Currently, the Zenith method is being put into practical use as a method for deoxidizing fats and oils such as fish oil, lard, beef tallow, coconut oil, rapeseed oil, and palm oil. However, vegetable oils such as palm oil tend to form emulsions during deacidification, making it difficult to put them into practical use. In particular, oils and fats with high acid values form emulsions immediately upon deacidification, and have not yet been put to practical use.

[0006] Furthermore, JP-A-50-103506 describes a method of deoxidizing fats and oils with an alkaline aqueous solution to which a water-soluble alcohol has been added. This method uses a machine to separate fats and soaps from fats and oils, and does not use a centrifuge to separate fats and soaps like the Zenith method.

[0007]

[Problems to be Solved by the Invention] When vegetable oils such as palm oil are deacidified using the Zenith method, an emulsion is formed during deoxidation, making it impossible to separate the alkaline aqueous solution and the oil. Problems such as a decrease in yield and an increase in the soap content of the deoxidized oil occur, which causes a decrease in the efficiency of the next steps of bleaching, curing, and deodorization. Therefore, when deacidifying fats and oils using the Zenith method, it has been desired to develop a method that suppresses the formation of emulsions during deacidification.

[0008] Accordingly, an object of the present invention is to provide a method for deacidifying fats and oils by suppressing the formation of emulsions when deacidifying fats and oils using the Zenith method and capable of achieving good deoxidation.

[0009]

[Means for Solving the Problems] As a result of intensive research, the present inventors have found that the above objective can be achieved by adding a specific amount of water-soluble alcohol to an alkaline aqueous solution when deoxidizing fats and oils using the Zenith method. I learned that it can be achieved. The present invention
This was done based on the above knowledge, and in the Zenith method of deoxidizing fats and oils using an alkaline aqueous solution, one water-soluble alcohol is added as an alkaline aqueous solution.
．． The present invention provides a method for deoxidizing fats and oils, which is characterized by using an aqueous alkali solution containing 0 to 10.0% by weight.

[0010] The method for deoxidizing fats and oils of the present invention will be described in detail below. Examples of the water-soluble alcohol used in the present invention include ethanol, propanol, isopropanol, and the like. The amount of the water-soluble alcohol added is 1.0 to 10.0% by weight, preferably 3.0 to 10.0% by weight in the alkaline aqueous solution.
It is 10.0% by weight.

[0011] If the amount of the water-soluble alcohol added is less than 1.0% by weight, the concentration is too low and the formation of an emulsion cannot be suppressed. Furthermore, even if the amount of the water-soluble alcohol added exceeds 10.0% by weight, little improvement in the effect of suppressing emulsion formation is observed. Furthermore, examples of the alkaline aqueous solution used in the present invention include a sodium hydroxide aqueous solution and a potassium hydroxide aqueous solution. Further, the alkaline aqueous solution has an alkaline concentration of 0.05 to
2 standard is preferred.

[0012] The method for deoxidizing fats and oils of the present invention is to deoxidize fats and oils using the aqueous alkaline solution to which 1.0 to 10.0% by weight of the water-soluble alcohol is added as the alkaline aqueous solution used in the deoxidizing step in the Zenith method. The process is the same as the normal Zenith method except for deoxidation. The method for deoxidizing fats and oils of the present invention includes animal fats and oils such as fish oil, lard, and beef tallow, rapeseed oil,
Can be used with vegetable oils such as palm oil, coconut oil, monkey fat, shea butter, etc.

[0013]

[Examples] The present invention will be further explained with reference to Examples below, but the present invention is not limited thereto. still,
The following percentages are by weight unless otherwise specified. Examples 1 to 3 0.3% phosphoric acid was added to 3 kg of sal fat crude oil (AV; 5.69) at 65° C., and the mixture was stirred for 15 minutes to remove oil-insoluble substances.

[0014] Next, ethanol was added at 1.0% and 3.0%.
A phosphoric acid-treated fat and oil was introduced from the bottom of a column (Zenith deoxidation tower) containing 8 liters of a 0.5 N aqueous sodium hydroxide solution (75°C) containing 5.0% of phosphoric acid (30 ml).
/min), and the introduced oil and fat are spread on a perforated plate with a diameter of 1 to 2 m.
Deoxidation was carried out by forming oil droplets of m in size and raising the droplets in an aqueous sodium hydroxide solution.

Results (emulsion generation rate during deoxidation,
The acid value, soap content, and yield of the obtained deacidified oil are shown in Table 1 below. Examples 4 to 7 The amount of ethanol added was fixed at 3.0%, and the concentration of the sodium hydroxide aqueous solution was changed to 0.05, 0.15, 0.35, 0.
The same process as in Example 1 was performed except that the standard was 70.

The results are shown in Table 2 below. Comparative Examples 1 to 4 Same as Example 1 except that phosphoric acid treated monkey fat was introduced into 0.15, 0.35, 0.50, 0.70 N aqueous sodium hydroxide solution (no alcohol added). Deacidification was performed.

The results are shown in Table 2 below. In addition, Example 2
The results of Comparative Example 1 are listed in both Table 1 and Table 2 below for convenience. In addition, * in Table 1 and Table 2 below
1, *2 and *3 indicate the following notes. *1 Emulsion occurrence rate (%) was measured as shown in Figure 1. That is, the oil phase amount L and emulsion phase amount L in the column (Zenith deoxidation tower) immediately after deoxidizing fats and oils are determined, and calculated using the following formula.

Emulsion incidence (%) = [l/(L+l)
]×100*2 Soap is calculated as sodium oleate. *3 The yield (%) of deoxidized oil is calculated using the formula below. [(Weight of deoxidized oil)/(Weight of crude oil)] x 100

00
19]

[Table 1] [Relationship between amount of alcohol added and emulsion generation rate]

[0020]

[Table 2] [Relationship between concentration of sodium hydroxide aqueous solution and emulsion generation rate]

[0021]

[Effects of the Invention] According to the method for deacidifying fats and oils of the present invention, when deacidifying fats and oils using the Zenith method, the emulsion that conventionally occurs during deoxidation is not generated, and the deoxidation can be performed well. can.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing means for calculating the emulsion incidence rate.

Claims (1)

[Claims] Claim 1: In a Zenith method of deoxidizing fats and oils using an aqueous alkaline solution, an aqueous alkaline solution to which 1.0 to 10.0% by weight of a water-soluble alcohol is added is used as the aqueous alkaline solution. A method for deoxidizing fats and oils.