JP5224033B2 - Method for producing polyfunctional alcohol fatty acid ester - Google Patents

Description

  The present invention relates to a method for producing a polyfunctional alcohol fatty acid ester in which an increase in bitterness over time is suppressed, a hue is good, and an acid value is reduced.

  Sugar alcohol is a kind of sugar produced by reducing the carbonyl group of aldose or ketose, and is also called alditol. Many sweeteners are used as low-calorie sweeteners because they are poorly absorbed from the small intestine into the body and do not easily become calories. Some have been praised for efficacy. For example, sorbitol, which is one of alditols, and sorbitan fatty acid ester, which is a fatty acid ester of sorbitan, which is an intramolecular condensate thereof, is a highly safe surfactant for the human body. Are widely used as emulsifiers.

Patent Document 1 describes that an organic solvent is used as a compatibilizer and a sugar alcohol and a fatty acid ester are transesterified to produce a polyfunctional fatty acid ester. Patent Document 2 describes that a polyfunctional fatty acid ester is produced by reacting a sugar alcohol and a fatty acid ester in the presence of a basic catalyst without using a solvent.
Japanese Patent Publication No. 36-19468 JP 49-35318 A

  Since the polyfunctional alcohol fatty acid ester has a low HLB and a high oiliness, it does not feel “bitterness” even if it is subjected to a sensory test alone. Therefore, until now, “bitterness” has not been regarded as important as a problem of sorbitan fatty acid esters.

  On the other hand, polysorbates (polyoxyethylene sorbitan fatty acid esters) scheduled to be approved as food additives are widely recognized as bitter substances. The polyoxyethylene sorbitan fatty acid ester is obtained by subjecting sorbitan fatty acid ester to an addition polymerization reaction with ethylene oxide.

However, since bitterness is disadvantageous for use as a food additive, the present inventor disclosed in Patent Document 3 a method for producing a polyoxyethylene sorbitan fatty acid ester. Here, sorbitan fatty acid ester as a raw material is purified with a composite metal oxide and then polymerized with ethylene oxide to succeed in reducing the bitterness of polysorbate.
JP 2006-96705 A

  Sorbitan fatty acid esters are already used as food additives. Sorbitan fatty acid ester alone does not show bitterness, but in actual use, it is blended with components having high HLB, etc., and if this blending imparts water solubility to the entire system, it may cause “bitterness”. It has become clear. For example, blends of polysorbates and sorbitan fatty acid esters have a strong bitterness. This bitterness has usually been thought to be due to polysorbates.

  However, even when the bitterness of the blend of polysorbates and sorbitan fatty acid esters is reduced by the purification process by the method described in Patent Document 3, it has been found that strong bitterness appears after storage for a certain period. This bitterness is attributed to sorbitan fatty acid esters and is thought to increase with time.

  For this reason, the addition amount of the polyfunctional alcohol fatty acid ester into the blending system must be kept to a very small amount so as not to develop bitterness over time, and there is a difficulty that the performance as an emulsifier cannot be fully exhibited. is there. For this reason, it has become a very disadvantageous element for use as a food additive and for expanding its use to pharmaceuticals, oral cosmetics, lip cosmetics, and the like. Of course, it is also essential to suppress the hue and acid value to low values.

  An object of the present invention is to provide a method for producing a polyfunctional alcohol fatty acid ester having a suppressed hue increase over time, a good hue, and a low acid value.

The present invention provides an ester (component A) of a fatty acid having 10 to 22 carbon atoms and a monohydric alcohol having 1 to 3 carbon atoms, and an alditol having 4 to 6 carbon atoms or an intramolecular condensate thereof (component B). ) To produce a polyfunctional alcohol fatty acid ester,
(1) A charging step in which component B having an aldehyde content of 50 ppm or less is mixed with component A as a 50 to 90% by weight aqueous solution;
(2) A dehydration step of dehydrating water in the system charged with component A and component B to 1.0% or less;
(3) A monovalent alcohol having 1 to 30% by weight of a monovalent alcohol having 1 to 30% by weight of a basic catalyst with respect to the total weight of Component A and Component B at 50 to 90 ° C. And (4) a step of completing the reaction at 1 to 20 kPa under a nitrogen stream at a temperature of 140 to 190 ° C.

  When the polyfunctional alcohol fatty acid ester obtained by the present invention is blended with a substance having a high HLB, the increase in bitterness with time is suppressed, the hue is good, and the acid value is kept low. Therefore, since it can be suitably used for pharmaceuticals, quasi drugs, cosmetics, and foods, it is extremely useful industrially.

Hereinafter, the present invention will be described in detail.
Component A is an ester of a fatty acid having 10 to 22 carbon atoms, preferably 12 to 18 carbon atoms, and a monohydric alcohol having 1 to 3 carbon atoms. This ester may be one kind or a mixture of two or more kinds.

  The fatty acid having 10 to 22 carbon atoms includes both saturated fatty acids and unsaturated fatty acids. The fatty acid having 10 to 22 carbon atoms may be natural or synthetic, and may be linear or branched. Specific examples include capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, behenic acid and the like.

  On the other hand, as C1-C3 monohydric alcohol, methanol, ethanol, 1-propanol, n-propanol etc. are mentioned, Preferably it is methanol and ethanol, More preferably, it is methanol.

  Specific examples of component A include methyl caprate, methyl laurate, methyl myristate, methyl palmitate, methyl stearate, methyl oleate, methyl linoleate, methyl linolenate, methyl arachidate, methyl behenate, etc. These are selected singly or in combination. Particularly preferred are methyl laurate, methyl myristate, methyl palmitate, methyl stearate, methyl oleate, and combinations thereof.

  Component B is an alditol having 4 to 6 carbon atoms or an intramolecular condensate of alditol having 4 to 6 carbon atoms. Specific examples include erythritol, arabitol, xylitol, ribitol, sorbitol, mannitol, galactitol, and intramolecular condensates thereof. Xylitol, sorbitol and their intramolecular condensates are preferred.

(1) Since preparation process component B is solid at normal temperature, when it is used for the reaction as it is, local heating occurs due to insufficient stirring, and the hue of the polyfunctional alcohol fatty acid ester finally obtained deteriorates. The bitterness becomes stronger. Therefore, it discovered that the component B in this invention can suppress these by using for reaction with aqueous solution.

  The concentration of the aqueous solution of component B is 50 to 90% by weight. These may use a commercially available thing, and may prepare aqueous solution before using for reaction.

The aldehyde content of Component B is 50 ppm or less, preferably 30 ppm or less, more preferably 10 ppm or less. When the aldehyde content exceeds 50 ppm, the hue of the resulting reaction product is deteriorated, and the bitterness with time is increased.
The aldehyde content of component B can be reduced by treatment with a fired activated composite metal oxide.

The measuring method of the aldehyde content of component B can be performed as follows.
(A) Collect 1 g of sample in a test tube with a stopper, add a fuchsin sulfite solution (Note 1), and seal tightly.
(B) This is mixed and left at room temperature for 30 minutes.
(C) About this solution, the light absorbency of wavelength 562nm and cell width 10mm is measured with an ultraviolet-visible spectrophotometer (JASCO Corporation V-530).
(D) A blank test is performed in the same manner using 1 g of water instead of the sample solution, and the absorbance at this time is set to 0 (reference).
(E) The same operation is performed using a formaldehyde standard solution (Note 2) to prepare a calibration curve, and the aldehyde content contained in the sample is determined from this calibration curve.

(Note 1 Preparation of fuchsin sulfite solution)
200 mg of basic fuchsin is weighed into a 200 mL volumetric flask, dissolved in 120 mL of warm water and allowed to cool. A solution obtained by dissolving 2 g of anhydrous sodium sulfite in 20 mL of water and 2 mL of hydrochloric acid are added thereto, and diluted to the mark with water. Leave for at least 1 hour before use and check for pink disappearance.

(Note 2 Preparation of formaldehyde standard solution)
Using formaldehyde with a known concentration, prepare a four-point solution of 1,10,50,100 ppm to create a calibration curve.

  In the present invention, the fatty acid compound of component A is used in an amount of 0.5 to 4.0 mol, preferably 0.5 to 3.5 mol, relative to 1 mol of the sugar alcohol of component B. If it is lower than 0.5 mol, the performance of the polyfunctional alcohol fatty acid ester obtained cannot be obtained, and if it is 4.0 mol or more, the reaction with the sugar alcohol of component B is not completed due to steric hindrance. This is because the remaining amount increases.

  The polyfunctional alcohol fatty acid ester of the present invention can be obtained by transesterification after adding a basic catalyst to Component A and Component B.

(2) Dehydration Step After mixing component A and component B, the system temperature is raised to 90 to 110 ° C. under a nitrogen stream while stirring, and under a nitrogen stream until water no longer evaporates under normal pressure. After stirring at 0 ° C., dehydration is performed at 90 to 110 ° C. at 4.00 kPa or less for 1 to 2 hours under a nitrogen stream, so that the water content at the start of the reaction is 1.0 wt% or less, preferably 0.5 % By weight or less, more preferably 0.2% by weight or less.

  When the water content exceeds 1.0% by weight, the acid value of the finally obtained polyfunctional alcohol fatty acid ester may exceed 5.

(3) Catalyst addition process After confirming that the water content at the start of the reaction is 1.0% by weight or less, the reaction system is cooled to 50-60 ° C, a basic catalyst is added, and the temperature is kept at the same temperature. Stir and disperse in the reaction system. The stirring time for dispersing is about 30 minutes to 1 hour.

  The basic catalyst is 0.1 to 1.0% by weight based on the total weight of Component A and Component B. Preferably 0.1 to 0.5% by weight, more preferably 0.1 to 0.3% by weight is added.

  Specific examples of the basic catalyst include lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium methoxide, sodium ethoxide, potassium t-butoxide, sodium carbonate, and the like. Preferably, sodium methoxide is used. is there.

  The basic catalyst is used by dissolving in a monohydric alcohol having 1 to 3 carbon atoms. When a basic catalyst is added in the form of a solid without being made into a monohydric alcohol solution, the reaction proceeds locally in the reaction system to cause coloration, and the polyfunctional alcohol fatty acid ester finally obtained over time Bitterness increases.

  The monohydric alcohol for dissolving the basic catalyst is specifically methanol, ethanol, 1-propanol, or isopropanol, and preferably methanol. As the monovalent alcohol-dissolved product of the basic catalyst, a commercially available product may be used, or an alcohol solution may be prepared before being subjected to the reaction. The monobasic alcohol-dissolved product of the basic catalyst is 1 to 30% by weight, preferably 10 to 30% by weight. When the amount is less than 1% by weight, the amount of monohydric alcohol added to the reaction system increases, which is not preferable because it requires time for the subsequent steps. If it exceeds 30% by weight, the basic catalyst is difficult to dissolve in monohydric alcohol at a concentration higher than that, which is not preferable. In this case, the water content of the monohydric alcohol is preferably low, and it is preferable to use a commercially available dehydrated product or a product dehydrated with an appropriate dehydrating agent.

  When adding the monohydric alcohol solution of the basic catalyst, the system temperature is cooled to 50 to 90 ° C, preferably 50 to 70 ° C, more preferably 50 to 60 ° C. If the temperature is lower than 50 ° C, the viscosity of the lower layer alditol becomes too high and stirring becomes difficult. If the temperature exceeds 90 ° C, the boiling point is close to or exceeds the boiling point of the monohydric alcohol in which the basic catalyst is dissolved. There is a danger of.

  At the same time as the basic catalyst, in order to expect the action of suppressing coloration in the system, even if one or more of phosphorous acid, hypophosphorous acid or their alkali salts is added in an amount that does not inhibit the action of the basic catalyst Good. Preferred is phosphorous acid or sodium hypophosphite.

(Transesterification reaction)
After adding the monohydric alcohol solution of the basic catalyst, the temperature in the system is increased under a nitrogen stream at normal pressure or 50 kPa to normal pressure until the system temperature reaches 140 to 190 ° C. When the temperature is raised under a pressure of 50 kPa or less, there are many monohydric alcohols in which the basic catalyst is dissolved at the beginning of the reaction at the time of raising the temperature, and lower alcohol is generated as the reaction proceeds. Therefore, there is a risk of bumping, which is not preferable.

  After the temperature increase, the reaction is carried out at a system temperature of 140 to 190 ° C., preferably 160 to 180 ° C. under a nitrogen stream at 1 kPa to normal pressure, preferably 10 kPa to normal pressure. When the system temperature is less than 140 ° C., the reaction rate becomes very slow, so a long reaction time is required, the heat history increases, and the bitterness of the polyfunctional alcohol fatty acid ester finally obtained increases. It is not preferable. When it exceeds 190 ° C., the hue of the final product is deteriorated, and the bitterness of the finally obtained polyfunctional alcohol fatty acid ester is also unfavorable.

(4) Reaction completion under reduced pressure The transesterification reaction of the present invention is initially a phase II system in which component A and component B are separated, but as the reaction proceeds, the polyfunctional alcohol produced Since fatty acid ester acts like a phase solvent, it changes from phase II to phase I.

  After determining that the reaction system has changed from phase II to phase I, the reaction is carried out at a system temperature of 140 to 190 ° C., preferably 160 to 180 ° C. in a nitrogen stream and 1 to 20 kPa, preferably 2 to 15 kPa. Continue and complete. When the reaction system changes from phase II to phase I, the reaction is progressing about 80 to 90% of the total, but in order to complete the remaining reaction, the reaction rate in the system is increased. Therefore, it is necessary to increase the degree of decompression. When the pressure in the system exceeds 20 kPa, the reaction rate is not expected to increase, and it takes time to complete the reaction, so the heat history increases, and the bitterness of the finally obtained polyfunctional alcohol fatty acid ester increases.

  In order to deactivate the basic catalyst after the transesterification reaction, mineral acids such as phosphoric acid, hydrochloric acid and sulfuric acid, short-chain aliphatic monocarboxylic acids such as formic acid, acetic acid, caproic acid and lactic acid, oxalic acid and succinic acid Neutralize with polyvalent carboxylic acids such as acid, malic acid, adipic acid and citric acid, aliphatic monocarboxylic acids such as benzoic acid and salicylic acid, and aromatic polycarboxylic acids such as phthalic acid, terephthalic acid and isophthalic acid. Or salting out and washing, or treatment with a synthetic adsorbent or ion exchange resin. In these processes, each operation may be repeated or different operations may be repeated. Further, if necessary, purification can be performed by decolorization treatment, dehydration and desolvation, steam deodorization, and activated carbon, and if there is unnecessary matter, it can be removed by centrifugation or filtration.

  In the present invention, after neutralization and purification of the polyfunctional alcohol fatty acid ester, in order to prevent deterioration over time, sorbic acid, dibutylhydroxytoluene, dibutylhydroxyanisole, propyl gallate, isopropyl citrate, guaiac acid, ethylenediamine One or more antioxidants such as disodium acetate and dl-α-tocopherol can be added.

  The polyfunctional alcohol fatty acid ester of the present invention is suitably used for pharmaceuticals, quasi-drugs, cosmetics, food applications, etc. because the increase in bitterness over time, hue, and acid value are suppressed compared to conventional products. Can do.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. For each compound, physical property values and sensory evaluation of bitterness were performed.

Example 1: Synthesis of xylitol monostearate
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 507 g of a 60% by weight aqueous solution of xylitol having an aldehyde value of 4.2 ppm and 715 g of methyl stearate under a nitrogen stream. Dehydration was carried out at 100 ° C. under normal pressure for 2 hours and further at 4.00 kPa or less for 1 hour, and the water content in the system became 0.15%. Thereto was added 10.2 g of a methanol solution of sodium methoxide prepared to 10% by weight and 0.10 g of sodium hypophosphite, and the temperature was raised to 180 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 180 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 6 hours. Thereafter, the reaction was further carried out at around 4.00 kPa at 180 ° C. under a nitrogen stream for 2 hours. After confirming that the methyl stearate spot disappeared by thin layer chromatography (TLC), the reaction was completed. After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed for 1 hour at 26.7 kPa or less, and then filtered to obtain xylitol monostearate.

[Measurement conditions for thin-phase chromatography]
TLC plate; Merck silica gel 60
Developing solvent; chloroform / n-butanol = 97/3 (v / v)
Dilution solvent; Chloroform Dilution concentration; Sample (sorbitan fatty acid ester) solution = 1 w / v%
Standard (fatty acid methyl) solution = 0.1 w / v%
Spot volume: 1 μL
Coloring solution; Phosphoric acid / copper sulfate aqueous solution (156 g of copper sulfate pentahydrate, 135 g of 85 wt% phosphoric acid aqueous solution are weighed in a 1 L volumetric flask and diluted to the marked line)
Coloring method: An aqueous solution of phosphoric acid / copper sulfate is applied, and after drying, heated in a thermostatic bath at 170 ° C. for 15 minutes.

(Example 2: Synthesis of sorbitol monopalmitate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet and vacuum line was charged with 455 g of an 80% by weight aqueous solution of sorbitol having an aldehyde value of 3.8 ppm and 648 g of methyl palmitate under a nitrogen stream. Dehydration was carried out at 90 ° C. under normal pressure for 2 hours and further at 6.67 kPa or less for 1 hour, and the water content in the system was 0.2%. Thereto was added 15.2 g of a methanol solution of sodium methoxide prepared to 20% by weight and 0.30 g of sodium hypophosphite, and the temperature was raised to 160 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 160 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 7 hours. Thereafter, the reaction was further carried out at around 4.00 kPa at 160 ° C. under a nitrogen stream for 2 hours, and the reaction was terminated after confirming that the spot of methyl palmitate had disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed for 1 hour at 26.7 kPa or less, and then filtered to obtain sorbitol monopalmitate.

(Example 3: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm and 710 g of methyl oleate under a nitrogen stream. Dehydration was performed at 110 ° C. under normal pressure for 2 hours and further at 4.00 kPa or less for 1 hour, and the water content in the system became 0.1%. 7.4 g of a methanol solution of sodium methoxide prepared to 28% by weight and 0.21 g of sodium hypophosphite were added thereto, and the temperature was raised to 170 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 170 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 6 hours. Thereafter, the reaction was further performed at 170 ° C. under nitrogen flow at around 2.67 kPa for 2 hours, and the reaction was completed after confirming that the spot of methyl oleate disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Example 4: Synthesis of sorbitan monostearate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.0 ppm and 715 g of methyl stearate under a nitrogen stream. Dehydration was carried out at 110 ° C. for 2 hours at normal pressure, and further at 2.67 kPa or less for 1 hour, and the water content in the system was 0.15%. Then, 5.6 g of a methanol solution of sodium methoxide prepared to 28% by weight and 0.16 g of sodium hypophosphite were added, and the temperature was raised to 170 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 170 ° C. and 66.7 kPa, and it was confirmed that the system became the I phase in 7 hours. Thereafter, the reaction was further carried out at around 4.00 kPa at 170 ° C. under a nitrogen stream for 2 hours. After confirming that the methyl stearate spot disappeared by thin layer chromatography (TLC), the reaction was completed. After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed for 1 hour at 13.3 kPa or less, and then filtered to obtain sorbitan monostearate.

(Comparative Example 1: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 328 g of sorbitan having an aldehyde value of 4.2 ppm and 710 g of methyl oleate at 110 ° C. under a nitrogen stream. Dehydration was performed for 2 hours at a pressure and further for 1 hour at 4.00 kPa or less, and the water content in the system was 0.1%. 7.4 g of a methanol solution of sodium methoxide prepared to 28% by weight and 0.21 g of sodium hypophosphite were added thereto, and the temperature was raised to 170 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 170 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 6 hours. Thereafter, the reaction was further performed at 170 ° C. under nitrogen flow at around 2.67 kPa for 2 hours, and the reaction was completed after confirming that the spot of methyl oleate disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 2: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet and vacuum line was charged with 469 g of a 70% by weight aqueous solution of sorbitan having an aldehyde value of 75.0 ppm and 710 g of methyl oleate under a nitrogen stream. Dehydration was performed at 110 ° C. under normal pressure for 2 hours and further at 4.00 kPa or less for 1 hour, and the water content in the system became 0.1%. 7.4 g of a methanol solution of sodium methoxide prepared to 28% by weight and 0.21 g of sodium hypophosphite were added thereto, and the temperature was raised to 170 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 170 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 6 hours. Thereafter, the reaction was further performed at 170 ° C. under nitrogen flow at around 2.67 kPa for 2 hours, and the reaction was completed after confirming that the spot of methyl oleate disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 3: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm and 710 g of methyl oleate under a nitrogen stream. Dehydration was carried out at 110 ° C. under normal pressure for 2 hours and further at 66.7 kPa or less for 1 hour, and the water content in the system was 2.5%. 7.4 g of a methanol solution of sodium methoxide prepared to 28% by weight of methanol and 0.21 g of sodium hypophosphite were added thereto, and the temperature was raised to 170 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out under a nitrogen stream at 170 ° C. and normal pressure, and it was confirmed that the system became phase I in 14 hours. Thereafter, the reaction was further performed at 170 ° C. under nitrogen flow at around 2.67 kPa for 4 hours, and the reaction was terminated after confirming that the spot of methyl oleate disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 4: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm and 710 g of methyl oleate under a nitrogen stream. Dehydration was performed at 110 ° C. under normal pressure for 2 hours and further at 4.00 kPa or less for 1 hour, and the water content in the system became 0.1%. Thereto, 2.1 g of sodium methoxide and 0.21 g of sodium hypophosphite were added, and the temperature was raised to 170 ° C. under normal pressure over 2 hours at 170 ° C. under nitrogen flow. It was confirmed that the system became phase I in 6 hours. Thereafter, the reaction was further performed at 170 ° C. under a nitrogen stream at around 2.67 kPa for 2 hours, and it was judged that the reaction was completed by confirming that the spot of methyl oleate had disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 5: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm and 710 g of methyl oleate under a nitrogen stream. Dehydration was performed at 110 ° C. under normal pressure for 2 hours and further at 4.00 kPa or less for 1 hour, and the water content in the system became 0.1%. 7.4 g of a methanol solution of sodium methoxide prepared to 28% by weight and 0.21 g of sodium hypophosphite were added thereto, and the temperature was raised to 170 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 170 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 6 hours. Thereafter, the reaction was further carried out at 170 ° C. under a nitrogen stream at around 2.67 kPa for 8 hours, and the reaction was terminated after confirming that the spot of methyl oleate had disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 6: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm and 710 g of methyl oleate under a nitrogen stream. Dehydration was performed at 110 ° C. under normal pressure for 2 hours and further at 4.00 kPa or less for 1 hour, and the water content in the system became 0.1%. 7.4 g of a methanol solution of sodium methoxide prepared to 28% by weight and 0.21 g of sodium hypophosphite were added thereto, and the temperature was raised to 120 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 120 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 20 hours. Thereafter, the reaction was further carried out at 120 ° C. under nitrogen flow at around 2.67 kPa for 6 hours, and the reaction was terminated after confirming that the spot of methyl oleate had disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 7: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm and 710 g of methyl oleate under a nitrogen stream. Dehydration was performed at 110 ° C. under normal pressure for 2 hours and further at 4.00 kPa or less for 1 hour, and the water content in the system became 0.1%. 7.4 g of a methanol solution of sodium methoxide prepared to 28% by weight and 0.21 g of sodium hypophosphite were added thereto, and the temperature was raised to 220 ° C. at normal pressure over 2 hours under a nitrogen stream. The reaction was carried out at 220 ° C. and atmospheric pressure, and it was confirmed that the system became phase I in 4 hours. Thereafter, the reaction was further carried out at around 2.67 kPa at 220 ° C. under a nitrogen stream for 1 hour, and the reaction was terminated after confirming that the spot of methyl oleate had disappeared by thin layer chromatography (TLC). After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 8: Synthesis of sorbitan monooleate)
In a 2000 mL four-necked flask equipped with a stirring blade, a temperature sensor, a nitrogen gas inlet, and a vacuum line, 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm, 677 g of oleic acid, 2.4 g of sodium carbonate, and Phosphorous acid 1.2g was charged, and the inside of the system was replaced with nitrogen for 30 minutes. The temperature was raised to 145 ° C. under a nitrogen stream, dehydrated at 145 ° C. under atmospheric pressure for 3 hours, then further heated to 235 ° C., reacted at 235 ° C. under a nitrogen stream, and in 6 hours. It was confirmed that the system was in phase I. Then, the reaction was further carried out for 2 hours at 235 ° C. under a nitrogen stream, and it was confirmed that the acid value was 6.0, and further that the acid value was not lowered even if reacted for 1 hour. The reaction was completed. After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

(Comparative Example 9: Synthesis of sorbitan monooleate)
In a 2000 mL four-necked flask equipped with a stirring blade, a temperature sensor, a nitrogen gas inlet, and a vacuum line, 469 g of a 70 wt% aqueous solution of sorbitan having an aldehyde value of 4.5 ppm, 677 g of oleic acid, 2.4 g of sodium carbonate, and Phosphorous acid 1.2g was charged, and the inside of the system was replaced with nitrogen for 30 minutes. The temperature was raised to 145 ° C. under a nitrogen stream, dehydrated at 145 ° C. under atmospheric pressure for 3 hours, then further heated to 235 ° C., reacted at 235 ° C. under a nitrogen stream, and in 6 hours. It was confirmed that the system was in phase I. Then, the reaction was further carried out for 2 hours at 235 ° C. under a nitrogen stream, and it was confirmed that the acid value was 6.0, and further that the acid value was not lowered even if reacted for 1 hour. The reaction was completed. After cooling, 25 g of water and KYOWARD 2000 (manufactured by Kyowa Chemical Industry Co., Ltd., magnesium oxide 60% by weight, aluminum oxide 30% by weight, composite metal oxide content 90% by weight, loss on drying is 0.8% by weight) Was added at 80 ° C. under a nitrogen stream at normal pressure for 1 hour, and then water was removed at 100 ° C. under a nitrogen stream at 6.67 kPa or less, followed by filtration to obtain sorbitan monooleate.

(Comparative Example 10: Synthesis of sorbitan monooleate)
A 3000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line is charged with 1200 g of N, N-dimethylformamide, and 328 g of sorbitan having an aldehyde value of 4.2 ppm is added and completely dissolved. Then, 710 g of methyl oleate and 2.1 g of potassium carbonate were added, the temperature was raised to 90 ° C. under atmospheric pressure with stirring at atmospheric pressure over 2 hours, and the reaction was continued at 90 ° C. and 20.0 kPa under nitrogen flow. It was confirmed that the system became phase I in 18 hours. Thereafter, the reaction was further carried out at 90 ° C. under nitrogen flow at around 15.0 kPa for 10 hours, and the reaction was terminated after confirming that the spot of methyl oleate had disappeared by thin layer chromatography (TLC). After most of N, N-dimethylformamide was distilled off under reduced pressure, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, filtered and sorbitan Monooleate was obtained.

(Comparative Example 11: Synthesis of sorbitan monooleate)
A 2000 mL four-necked flask equipped with a stirring blade, temperature sensor, nitrogen gas inlet, and vacuum line was charged with 328 g of sorbitan having an aldehyde value of 4.2 ppm and 710 g of methyl oleate at 110 ° C. under a nitrogen stream. Dehydration was performed for 2 hours at a pressure and further for 1 hour at 4.00 kPa or less, and the water content in the system was 0.1%. 2.1 g of potassium carbonate was added thereto, and the temperature was raised to 180 ° C. at atmospheric pressure over 2 hours under a nitrogen stream. The reaction was continued at 180 ° C. and 20.0 kPa under a nitrogen stream, and in 10 hours, the system was replaced with I. Confirmed to be in phase. Thereafter, the reaction was further carried out for 6 hours at 180 ° C. under a nitrogen stream at about 15.0 kPa. After confirming that the spot of methyl oleate disappeared by thin layer chromatography (TLC), the reaction was terminated. After cooling, 1.0% by weight of Kyoward # 700 was added at 80 ° C., adsorbed at 13.3 kPa or less for 1 hour, and then filtered to obtain sorbitan monooleate.

  Regarding the composites obtained in the above Examples and Comparative Examples, the “acid value” and “hue (APHA)” described in the reference oil analysis test method were measured. As for “bitterness”, sensory evaluation was performed immediately after synthesis and after 6 months according to the following procedure.

  Each 5.0 g of the resultant composite was precisely weighed, and 5.0 g of food additive grade propylene glycol was added thereto, and stirred with a glass rod until uniform. About each obtained mixture, how to feel "bitterness" when 0.3g was put on the tongue directly and tasted for about 10 seconds was evaluated by the 10 panelists in the following 5 levels, and the average value was adopted. did. When the average value of 10 panelists performing a five-step evaluation on each mixture was 1 or more and less than 3.0, it was evaluated that the bitterness was less suitable for use in the mouth (in Tables 1 and 2). ○ ”). On the other hand, in the case of 3.0 or more, it was evaluated that it was bitter and not suitable for use in the mouth (shown as “x” in Tables 1 and 2).

  The food additive grade propylene glycol used in this test was used after confirming that it did not feel any “bitterness” when tasted directly on the tongue.

1: Little bitterness
2: Some bitterness remains
3: Some bitterness remains
4: Strong bitterness remains
5: Strong bitterness remains

  The composites obtained in Examples and Comparative Examples and their evaluation are shown in Tables 1 and 2. In the “judgment” section, the evaluation of “bitter” is “○” both immediately after synthesis and after 6 months, “hue” is Gardner and “3 or less”, and “acid value” is “5 or less”. When satisfying, “◯”, otherwise “×”.

* 1:
Transesterification: Method of reacting sugar alcohol with fatty acid methyl Direct acid method; Method of reacting sugar alcohol with fatty acid * 2 Catalyst; Comparative Examples 12 and 13 are sodium carbonate, otherwise sodium methoxide * 3 Catalyst amount; Lower alcohol Even in the case of a solution, the amount of basic catalyst added is described. * 4 Reaction temperature; temperature at which sugar alcohol is reacted with fatty acid methyl or fatty acid

In Examples 1 to 4, good results were obtained.
In Comparative Examples 1-7, 10, and 11, the production conditions of the present invention were not met, and the product was purified by Kyoward, but all suffered from bitterness after 6 months. In particular, in Comparative Examples 1 and 4, it was found that there was no bitterness in the initial stage, but bitterness occurred over time.

In Comparative Examples 8 and 9, sorbitan monooleate was synthesized by the direct acid method and purified by Kyoward. This is the same as the manufacturing method described in Patent Document 3. In this case, however, bitterness occurred after 6 months. In particular, in Comparative Example 9, there was no bitterness in the initial stage, but the bitterness increased with time.

Claims (1)

Reacting an ester (component A) of a fatty acid having 10 to 22 carbon atoms and a monohydric alcohol having 1 to 3 carbon atoms with an alditol having 4 to 6 carbon atoms or an intramolecular condensate thereof (component B). By which a polyfunctional alcohol fatty acid ester is produced,
(1) A charging step in which the component B having an aldehyde content of 50 ppm or less is mixed with the component A as a 50 to 90% by weight aqueous solution;
(2) a dehydration step of dehydrating the water in the system charged with the component A and the component B to 1.0% or less;
(3) 1 to 30% by weight of 1 to 30% by weight of basic catalyst with respect to the total weight of component A and component B at 50 to 90 ° C. And (4) a method for producing a polyfunctional alcohol fatty acid ester characterized by comprising a step of completing the reaction at 1 to 20 kPa under a nitrogen stream at a temperature of 140 to 190 ° C.