JPS5846238B2 - Edible oil manufacturing method - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for producing edible oil with good flavor.

In general, vegetable oils produce an unpleasant odor (hereinafter referred to as "light") when stored under the irradiation of light such as sunlight or the light of various electric lamps (in the presence of light).

) occurs. Since these odors significantly impair the flavor of vegetable oils, a number of improvement methods have been devised in the past, but no fundamental solution is known.

For example, as shown in Japanese Patent Publication No. 49-2162, the method of adding β-carotene is a useful method for suppressing photopic effects due to the ability of β-carotene to absorb light energy; The problem was that the product value decreased due to red coloring.

In view of these points, the present inventors have conducted extensive research, and as a result, they have incorporated β-carotene into refined vegetable oil and have 1.
It was discovered that edible oil obtained by heating at a temperature of 50'C to 220°C for 20 minutes to 5 hours can suppress deterioration due to light. It has been revealed that the above effects can be achieved by containing 2pI)fi1 or more, and the present invention has been completed.

In the present invention, refined vegetable oils include vegetable oils such as soybean oil, rapeseed oil, cottonseed oil, sunflower oil, corn oil, safflower oil, rice bran oil, peanut oil, sesame oil, and olive oil.
Refers to products purified using normal methods.

Typical purification methods include steps such as degumming, deacidification, decolorization, dewaxing, and deodorization.

In any case, if complete deodorization is performed, the β-carotene normally present in the raw material oil will be completely thermally decomposed and removed.

That is, this deodorizing process is performed under reduced pressure (2 mmHg to 10 mmHg).
FimH, 9) refers to the process of heating the oil to 2200C to 250C while blowing steam to remove odor components contained in the oil, and is usually maintained in this temperature range for 30 minutes to 2 hours.

Beta-carotene is added to the purified vegetable oil produced through the usual refining process.

β-Carotene is allowed as a food additive, and is a substance present in green leaves, flowers, fruits, roots, etc. of plants, and blood, organs, fat, egg yolk, milk, etc. of animals.
o, indicated by H56.

This β-carotene is contained in an amount of 2 ppIn or more, usually 30% or less, based on the refined vegetable oil.

Then, the purified vegetable oil containing β-carotene is heated at 150°C to 220°C, preferably 170°C, under reduced pressure.
Heat in the range of 210° C. to 210° C. for 20 minutes to 5 hours.

This heating step differs from the commonly performed deodorizing step in two respects as described below.

First, the heating temperature is 150°C to 220°C, which is lower than the deodorizing process.

Second, the mixture containing β-carotene is heated under reduced pressure.

Therefore, due to this heating step, β-carotene is partially thermally decomposed but not completely decomposed and removed, and remains as σ in the refined vegetable oil.

This β-carotene thermal decomposition product, like β-carotene, has the effect of suppressing the generation of photopic odor, but unlike β-carotene, it is not a deep red color, but a pale color, and it is resistant to visible light. Judging from absorption etc., it is inferred that it is a mixture of compounds containing conjugated octaene, conjugated heptaene, and conjugated hexaene.

The refined vegetable oil containing the above β-carotene pyrolysis product is
It is used by adding an appropriate amount to purified vegetable oil that does not contain β-carotene.

In this case, the effect of the present invention can be exerted on the era name as long as the amount added is an amount necessary to make the content of β-carotene in terms of β-carotene before thermal decomposition equal to or more than 2,000 ppm, and usually less than i,000 ppm.

It goes without saying that within this range, the amount added can be changed as appropriate depending on the quality of the oil required.

For example, if the refined soybean oil contains 1% β-carotene and is thermally decomposed, the refined soybean oil will contain 0.02% β-carotene.
It may be added by 10% to 10%.

Also, from the beginning, 2pp of β-carotene is added to refined soybean oil.
Oil containing 1 to 1,000 ppm of pyrolysis may be used as is.

In summary, the present invention has discovered the following.

(1) By adding β-carotene to refined vegetable oil and heating it under reduced pressure, β-carotene thermal decomposition* could be produced.

(2) The β-carotene thermal decomposition product thus obtained had the effect of suppressing the deterioration of vegetable oils due to light in the presence of oxygen.

(3) The β-carotene thermal decomposition product was a relatively light-colored oil even when added to edible oil.

The present invention solves the problem of deterioration of edible oils caused by light, which has been a concern for some time, and makes a significant contribution to the edible oil industry.

The present invention will be described in detail below from the implementation side.

Example 1 Refined soybean oil i, ooog and β-carotene (Merck ff.
) was added and heat treated in a Claisen flask under reduced pressure (approximately 2 mmH&) at the temperature and time shown in Table 1 without blowing in steam.

The heated oil was returned to room temperature and the color tones of yellow Y and red R were measured using the Lovibond colorimetric method.

The oils were stored for 1 to 4 weeks under indoor lighting (approximately 1,000 lux), and after storage, each oil was evaluated for photopic odor generation by a well-trained panel of 10 people.

The results are shown in Table 1.

In the table, the judgment is - No bright spot odor ±: Does it smell in bright light? +: Bright odor ++: Strong photopic odor ＋←There is a very strong light odor. It was displayed using a 5-level symbol.

Add 500 pIll of β-carotene and heat at 130°C for 50 minutes.
The oil heated at 220° C. for 20 minutes exhibited suppressed photopic odor and was a light-colored oil.

Various amounts of soybean oil containing pyrolyzed β-carotene (Sample C of Example 1) were added to purified vegetable oil, and color tone and light storage tests after blending were conducted.

The results are shown in Table 2.

As a comparative example, undecomposed β-carotene was added to soybean paste oil so that the color tone after addition was the same as Samples J and L, and a light storage test was conducted.

The results are shown in Table 2-b.

Example 3 After adding soybean oil containing a β-carotene pyrolysis product (sample C of Example 1) to rapeseed oil, cottonseed oil, and corn oil, a light storage test was conducted.

Although the type of flavor and odor differs depending on the oil, Table 3 shows the evaluation results for only the bright oils.

Example 4 Raw palm oil obtained by extracting oil from Malaysian palm pulp was subjected to conventional deacidification, decolorization, and fractionation steps to obtain fractionated palm oil (a).

This palm fractionated oil contained 70811F of β-carotene.

This palm fractionated oil was heated at 200° C. for 1 hour under reduced pressure (b), and heated at 180° C. for 3 hours (c).

On the other hand, a deodorizing process (heating at 260° C. for 1 hour while blowing steam under reduced pressure) using the conventional method of palm fractionation oil was carried out to obtain refined palm oil (d).

After blending (a), (b), (c) and (d) with refined soybean oil (e), color tone and light storage tests were conducted.

The results are shown in Table 4.

Claims (1)

[Claims] 1. Refined vegetable oil containing β-carotene was heated under reduced pressure for 15 minutes.
It is characterized in that a heat-treated product of β-carotene obtained by heat treatment at 0°C to 2206C for 20 minutes to 5 hours is added to a vegetable oil of 2PpI11 or more in terms of the amount of β-carotene before heat treatment. Method for producing edible oil.