JPH0542261B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to a method for treating fats and oils with at least two types of enzymes.

[Conventional technology]

The existence of enzymes that specifically act on partial glycerides and their purification methods are known [for example, S. Okumura et al., J. Biochemistly, 87 , 205
(1980)], the use of this specific enzyme has attracted attention in the past because it can be used in combination with other enzymes that do not have this specificity (rather, enzymes that hydrolyze triglycerides well) to quickly convert glyceride oils and fats. It is completely hydrolyzed, and other effective uses have not yet been found.

On the other hand, a method of transesterifying fats and oils using lipase is known and is useful for selectively transesterifying the 1- and 3-positions of glycerides, but it has the disadvantage of easily producing partial glycerides.
In particular, if a diglyceride component is included, it will form a eutectic mixture with triglycerides, resulting in a decrease in solid fat index, a drop in melting point, a decrease in fractionation accuracy, and a delay in crystal transition (α-type → β′-type → β-type). So, if you are trying to get hard butter, there is a quality problem.

[Problem that the invention seeks to solve]

When using any of the above lipolytic enzymes to obtain triglyceride as a final product, attention should be paid to improving the yield. In the case of enzymatic transesterification, a method has already been proposed in which the yield of triglyceride is increased and the production or persistence of diglyceride is suppressed by removing as much water as possible from the system. In the system in which this reaction is applied, the production of free fatty acids is unavoidable, and there is a limit to the removal of water in the system. In addition,
When alkaline deacidification, which is the most common deacidification method, is employed to remove the generated fatty acids, the yield of triglycerides is usually further reduced.

However, the present inventor discovered that if triglycerides are first treated with a partial glyceride-specific enzyme while suppressing their decomposition, the resulting fatty acids can be effectively used in the next transesterification reaction without the need to remove them. I came up with the idea and completed this invention.

[Means and actions for solving problems]

This invention involves applying a partial glyceride-specific enzyme to glyceride fats and oils in the presence of a small amount of water, and then
The enzyme and aqueous fraction are removed from the reaction product, and then fatty acids, fatty acid esters, or other glyceride fats are added if necessary, and the glyceride fats are fractionated after the action of 1- and 3-position specific enzymes. This is a method for enzymatically treating fats and oils.

That is, by allowing the partial glyceride specific enzyme to act before the action of the 1-, 3-position specific enzyme, fatty acids are removed (deoxidized) from the reaction product produced by the action of the partial glyceride specific enzyme. instead, fatty acids can be used as a source of fatty acid introduction into glycerides in transesterification reactions,
In addition, since the diglyceride content of the transesterification raw material fat is reduced, the diglyceride content of the resulting transesterification oil can also be reduced.

The raw material glyceride fat on which the partial glyceride-specific enzyme acts is usually an oil containing 2% or more diglyceride in the glyceride, but fats and oils with a low diglyceride content originally have little adverse effect on triglycerides, so this partial glyceride-specificity It has little effect on enzymatic action. The origin of the raw material oil is not limited, but if the target oil is hard butter, olive oil, oleracea flower oil, camellia oil, palm oil, rapeseed oil (Zero
Erucic type), shea butter, monkey fat, mango fat,
Corcum, Borneo tallow, Malabar fat, etc.
Alternatively, oils and fats obtained by processing these by fractionation etc. are exemplified, and oils and fats in which the fatty acid bonded to the 2-position is rich in oleic acid are generally 70% or more. In particular, when the glyceride fat on which a partial glyceride-specific enzyme is applied contains a liquid fraction of transesterified fat obtained by the action of a 1-, 3-position-specific enzyme, diglyceride produced during the transesterification reaction It is particularly useful because the components are concentrated in this fraction.

The existence and purification method of partial glyceride-specific enzymes are known as described above, but
It can be used regardless of its microbial origin. However, according to the knowledge of the present inventors, selectivity is better when the amount of enzyme used is such that its titer is not too high. That is, the enzyme titer is 1 μM per minute.
The amount of enzyme that liberates p-nitrophenol is preferably 5 units or less per 1 g of substrate, particularly preferably 0.01 to 0.1 units/g.
It is a substrate. A time of 10 minutes to 24 hours is usually sufficient, but if the amount of enzyme is large and the enzyme is allowed to act for a long time, triglyceride decomposition may occur more easily, so it is usually best to keep it within 4 hours.
The action temperature is usually in the range of 20 to 85°C, and may be determined as appropriate depending on the enzyme used.

The presence of a small amount of water is necessary in the system in which the partial glyceride-specific enzyme acts, and the water content is usually 0.2% or more, preferably 1% or more, and optimally about 5 to 1% of the substrate glyceride fat. Make it so. If the water content is low, the partial glyceride-specific enzyme will hardly work, and adding too much water will have little effect.

The enzyme and aqueous fraction are removed from the reaction, which removes glycerol, which forms part of the reaction, but substantially no free fatty acids.
If necessary, glycerol can be removed more completely by further washing with water and dehydration. If glycerol remains in the system, like water, it becomes a factor that increases partial glyceride in the subsequent transesterification reaction.

Next, if necessary, add a fatty acid introduction source such as a fatty acid, fatty acid ester, or other glyceride fat, and add 1
A transesterification reaction is carried out by the action of a -, 3-position specific enzyme, but if a large amount of fatty acid is added, it usually requires the use of a solvent, so alcohol esters of fatty acids or glyceride fats and oils are preferable to fatty acids. is desirable. However, this invention does not exclude the use of a solvent in the transesterification reaction. When the target product is hard butter, the type of fatty acid to be introduced is preferably mainly palmitic acid or stearic acid. When the introduced fatty acid is an alcohol ester of a fatty acid, the alcohol is preferably a lower monohydric alcohol having 1 to 4 carbon atoms.

Moisture in the transesterification reaction system is removed from the beginning or during the reaction by drying the water in the system (enzyme,
0.18% of the substrate (including water derived from the solvent)
The following is preferable for suppressing the production of partial glycerides, and in combination with treatment with a partial glyceride-specific enzyme, a reaction oil with a lower diglyceride content can be obtained. An enzyme agent that exhibits excellent transesterification activity in a low-moisture system or a dry system as described above is one obtained by dispersing, adsorbing, or bonding the enzyme to a carrier under hydrogen, and then slowly drying the resultant. In addition, there are some substances that can be used even if they have not been particularly processed, although they have weak activity, such as enzymes bound to bacterial cells. Of course,
In the above system, the type of enzyme and the preparation method are not limited as long as it has transesterification activity and exhibits the desired selectivity.

The selectivity of transesterification is 1-,
It has the property of transesterifying the 3-position but hardly transesterifying the 2-position, and enzymes exhibiting such selectivity can be used regardless of whether they are of animal or plant origin or microbial origin. The transesterification reaction is generally carried out at a temperature in the range of 20 to 75°C.

Glyceride fats and oils are separated from the transesterification product. Distillation, adsorption, and alkaline deacidification methods can be used to separate fatty acids or fatty acids and lower alcohol esters of fatty acids from glyceride fats and oils.

The fractionated glyceride fat is used as it is or by fractionation to remove the high melting point portion or the low melting point portion to obtain the desired fat or oil. When the low melting point portion is removed, as described above, this portion contains a relatively large amount of diglyceride, so it can be treated again with a partial glyceride specific enzyme and recycled as part or all of the transesterification raw material.

Free fatty acids or lower alcohol esters thereof separated from glyceride fats and oils can be hydrogenated or subjected to esterification treatment, and these can also be recycled as part of the raw materials for the transesterification reaction.

〔effect〕

The main effects of this invention are as mentioned above.
Free fatty acids produced by treatment with specific enzymes can be used as raw materials for transesterification reactions,
Therefore, it is possible to reduce the deoxidation loss that would normally occur, and secondly, it is possible to reduce the diglyceride content in the target fat or oil, or to reduce the amount of deoxidation loss that would normally occur. This can contribute to the acceleration of the reaction, such as by reducing the amount of diglyceride produced.

〔Example〕 This invention will be explained below with reference to Examples.

Example 1 As a partial glyceride-specific enzyme, an enzyme manufactured by Amano Pharmaceutical Co., Ltd. (trade name "Lipase G") obtained from a bacterium of the genus Penicillium (the above titer per mg of enzyme) was used.
Using 4.2 U), 1 part of commercially available Rhizopus deremer lipase and 2 parts of diatomaceous earth were mixed as a 1-, 3-position specific enzyme, and the mixture was made into granules by sprinkling and stirring with an appropriate amount of cold water. The following enzyme treatment was carried out using diatomaceous earth enzyme with a moisture content of 1.5% that had been slowly dried under reduced pressure at ℃.

That is, a palm mid-melting point fraction with a diglyceride content of 5.7% and an acid value (AV 0.25) was used as a substrate, and 0.01% of a partial glyceride-specific enzyme and 10% of water were added to this substrate and the enzyme was incubated at room temperature for 1 hour. After the reaction, the enzyme and water were removed, and the yield was
99.5%, diglyceride content 1.2%, and acid value 10.5. (For reference, the yield was 92% when the fats and oils in which partial glycerides were selectively hydrolyzed in the same manner as above were separately deoxidized with alkali using a conventional method.)
Mix an equal amount of ethyl stearate to this and add water.
Using the dried 0.01% substrate as a substrate, transesterify by adding 10% 1-, 3-position specific enzyme, and when the reaction rate reaches 90%, separate the glyceride fat (diglyceride content 2.5%). Then, hard butter was obtained by removing the high melting point part by a conventional method (diglyceride content 1.3%, cooling curve by Jensen method).
Tmax is 29.5℃). Using this, we made a prototype of Chiyokolate, which was excellent in both workability and heat resistance.

For comparison, an example was also carried out in which hard butter was obtained by transesterification in the same manner, except that a mid-melting point fraction of palm without the action of a partial glyceride-specific enzyme was mixed with ethyl stearate. The diglyceride content of the obtained hard butter was 4.2%, and the Tmax was 27.5°C.

Example 2 At the time of initial onset, refined oleracea flower oil
30 parts of ethyl stearate and 70 parts of ethyl stearate were heated and dried under reduced pressure, passed through a column packed with the 1-, 3-position specific enzyme (water content in the system: 0.01%), and the passed through column was
Single distillation was carried out at 220°C 3 mmHg, followed by steam distillation at 230°C 3 mmHg, so that the ratio of the fractions distilled off at each stage was approximately 95:5, and the latter fraction was a small amount (the amount after the next curing was 70:5). The acid value was reduced to 3 by adding oleic acid and excess ethanol using a sulfuric acid catalyst. teeth
10) is recycled as a reaction raw material for transesterification, and the glyceride fats and oils left over from distillation are separated using a solvent to obtain the solid side as hard butter.
High oleic horsetail flower oil was added to the liquid fraction to make 30 parts, and this was also recycled as a raw material for glyceride fat in the transesterification reaction in a reaction system.
A treatment was performed to selectively hydrolyze partial glycerides. That is, a partial glyceride-specific enzyme was allowed to act on the liquid fraction of the glyceride oil and fat recovered from the transesterification product, and the enzyme and the aqueous fraction were separated, followed by addition of foliage flower oil.

In the above circulation, the acid value of the substrate for the partial glyceride-specific enzyme is 0.31, and the diglyceride content is 6.2%.
After the enzyme was applied, the acid value was 9.3 and the diglyceride content was 1.8%.

Example 3 Example 2 except that the water content in the system when passing through the column was 0.04%, and the ratio of the fractions distilled off in each step of simple distillation and steam distillation of the transesterification product was approximately 90:10. A continuous reaction similar to that was carried out. The reactivity of transesterification was 120% compared to Example 2, but
There was no inferiority in product quality compared to the case of Example 2 in which the partial glyceride-specific enzyme was not used.

Example 4 Shea butter low melting point fraction (diglyceride content 6.5%)
Example 1 was repeated except that methyl palmitate and methyl palmitate were used in place of palm mid-melting fraction and ethyl stearate. The diglyceride content in the obtained hard butter was 1.6%.

Claims (1)

[Claims] 1. After allowing a partial glyceride-specific enzyme to act on glyceride fats and oils in the presence of a small amount of water, the enzyme and aqueous fraction are separated from the reaction product, and then, if necessary, fatty acids, fatty acid esters, A method for enzymatic treatment of fats and oils, which comprises adding other glyceride fats and oils, allowing a 1-, 3-position specific enzyme to act thereon, and then separating the glyceride fats. 2. The treatment method according to claim 1, wherein the glyceride oil or fat on which a partial glyceride-specific enzyme is applied contains a liquid fraction of a transesterified oil or fat obtained through the action of a 1-, 3-position-specific enzyme. .