JPH0550498B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel glutamate salt having stable physical properties and useful as a seasoning. Sodium salt of glutamic acid (MSG) is widely used as a versatile umami seasoning because it has good taste. On the other hand, in addition to sodium salts, glutamate salts include potassium salts, calcium salts, ammonia salts, etc. In particular, potassium salts have a taste that is relatively similar to monosodium glutamate, and there has been a recent trend toward lower sodium glutamate salts. Its use is attracting attention because it corresponds to the current situation. However, when using potassium salt of glutamic acid as a seasoning, there are major problems in its practical application. That is, since potassium salts are more deliquescent than sodium salts, physical properties deteriorate due to deliquescence whether potassium salts are used alone or in combination with other taste/flavor substances. Furthermore, when used in combination with other taste/flavor substances, the taste and flavor are likely to deteriorate due to deliquescence of the potassium salt. Therefore, in the case of seasonings containing potassium salts, there is a strong demand for improvement in storage stability by preventing the potassium salt from deliquescing. Against the background of the above-mentioned current situation, the present inventors have conducted intensive research to develop a method for producing seasonings that contain potassium glutamate and have improved deliquescent properties.
He discovered calcium salts and completed the present invention. That is, the present invention has the formula Glu ₃ KCa·nH ₂ O (n=0~
The novel glutamate represented by 1), its production method, and seasonings containing it. Figure 1 shows the powder X-ray diffraction pattern of the monohydrate of the novel glutamate of the present invention, and it shows that both potassium glutamate (monohydrate) (Figure 2) and calcium glutamate (tetrahydrate) , the diffraction angle peaks are different, and it is clear that the novel glutamate of the present invention is not just a mixture of potassium glutamate and calcium glutamate.
Physically, the potassium/calcium glutamate salt of the present invention has a lower deliquescent property than a potassium salt alone or a mixture of a potassium salt and a calcium salt. Further, the existence of the potassium/calcium glutamate salt referred to in the present invention is supported by the mutual solubility curve of potassium glutamate-calcium glutamate-aqueous system. The mutual solubility curves at 30°C are shown in Figure 4, in which A to B are monohydrate of potassium glutamate as the stable liquid base, and B to B are the stable liquid bases.
C is a stable liquid base monohydrate of the potassium/calcium glutamate salt of the present invention, and C to D are:
Calcium glutamate tetrahydrate is a stable liquid substrate. That is, when the potassium and calcium concentrations in the coexisting aqueous solution take values between B and C, the monohydrate of the potassium-calcium glutamate salt of the present invention is stably crystallized from the aqueous solution. As for the elemental analysis values of the monohydrate of the potassium/calcium glutamate salt of the present invention, as shown in Table 1, the calculated values and the analytical values show good agreement.

[Table] As a specific example of the method for producing potassium/calcium glutamate salt of the present invention, potassium and calcium were adjusted to values between B and C in Figure 4.
An aqueous solution containing glutamic acid, potassium ions, and calcium ions is prepared, and the aqueous solution is stirred and left to cool to crystallize and separate the potassium/calcium glutamate monohydrate of the present invention as a double salt.
The crystallization and fractionation methods and conditions may be according to conventional methods and are not particularly limited. If the obtained potassium/calcium glutamate salt is heated and dehydrated in a conventional manner, an anhydride of potassium/calcium glutamate can be obtained. The physical properties of the monohydrate crystals of potassium/calcium glutamate obtained in Example 1 are shown below. (1) X-ray diffraction The potassium/calcium glutamate salt (monohydrate) of the present invention measured by powder X-ray diffraction using CuKα radiation is shown in Figure 1 as potassium glutamate monohydrate and calcium glutamate tetrahydrate. The diffraction pattern of is shown in FIGS. 2 and 3. (2) Light intensity Potassium/calcium glutamate monohydrate
[α] ²⁰ _D = +26.3 to +26.4 Potassium glutamate monohydrate
[α] ²⁰ _D = +22.5 to +24.0 Calcium glutamate tetrahydrate [α] ²⁰ _D = +22.5 to 24.0 (2.5NHCl) (3) Critical humidity Potassium/calcium glutamate monohydrate
85.6% (measurement temperature 24.5℃) Potassium glutamate monohydrate
61.9% (〃 24.9℃) Calcium glutamate tetrahydrate
97.1% (〃 25.2℃) When used alone, the potassium/calcium glutamate of the present invention has bitterness and astringency in addition to so-called umami, but when used as a seasoning, it is evaluated as having a complex taste and a thick taste. In particular, it does not show deliquescence for a long time in an atmosphere at room temperature and normal pressure, and has a remarkable feature compared to potassium glutamate alone or a mixture of potassium glutamate and calcium glutamate, which deliquesce. Therefore, whether used alone or in combination with other ingredients, it can maintain stable physical properties for a long period of time and is highly useful as a low-sodium seasoning. The present invention will be further explained below with reference to Examples. Example 1 160 g of potassium glutamate monohydrate and 30 g of calcium glutamate tetrahydrate were dissolved in 100 c.c. of water and stirred at 30°C. Crystals began to precipitate after about 30 minutes and were separated after 18 hours. After washing the crystals twice with a methanol:water (8:2) mixture,
When dried under reduced pressure at °C, 30 g of crystals were obtained (Glu ₃ KCa·H ₂ O). The elemental analysis values of the obtained crystals are shown in Table 1 (described above).
The X-ray diffraction diagram is shown in FIG. When a 0.2% aqueous solution of these crystals was prepared and subjected to sensory evaluation by 20 well-trained taste panels, it was found that compared to monosodium glutamate, the quality of umami,
Although the strength was the same, it was evaluated as having a slightly bitter and astringent taste. In addition, when we measured the critical humidity of this crystal, we found that
It was 85.6% at 24.5°C, and when the crystals were left in a constant temperature and humidity chamber (temperature 24°C, relative humidity 73%) and their deliquescent properties were measured, they were compared with the control potassium glutamate, potassium glutamate, and calcium glutamate. An equimolar mixture of about 30 min for about 15 min each
In contrast, the crystals of the present invention did not deliquesce or solidify after 24 hours and remained in their original powder state. Example 2 Add 200ml of water and 153g of glutamic acid to make a slurry solution, and add 48.5g of potassium hydroxide and Ca.
After neutralizing and dissolving with 6.7 g of (OH) ₂ , it was concentrated twice. Then, while cooling, 4g of potassium/calcium glutamate salt was added as a seed crystal to 30°C.
After 1 hour, the crystals were separated. The crystals were washed with a methanol:water (8:2) mixture and dried under reduced pressure to obtain 42 g of crystals. This crystal was similar to the potassium/calcium glutamate salt obtained in Example 1. Example 3 When the potassium/calcium glutamate monohydrate obtained in Example 1 was dried at 120° C. under reduced pressure for 3 hours, anhydrous potassium/calcium glutamate was obtained. Using a composition in which 1 part of this anhydride and 1 part of sodium glutamate were mixed, the sample was prepared by adding and dissolving this composition in 0.6% saline solution to a concentration of 0.2%, and as a control, potassium glutamate and calcium glutamate were each mixed. Alone in 0.6% saline
Using the solution added to give a concentration of 0.2%,
A sensory evaluation was conducted by 20 well-trained taste panels. The results are shown in Table 2.

[Table] Next, the potassium glutamate/calcium anhydride of the present invention obtained above was heated to 24°C in the same manner as in Example 1.
When the powder was left in a constant temperature and humidity chamber at 73% relative humidity and 73% relative humidity, it did not deliquesce even after 24 hours and retained its original powder properties.

[Brief explanation of drawings]

Figure 1 shows Glu ₃ KCa・H ₂ O, Figure 2 shows GluK・
H ₂ O, Figure 3 shows the powder X-ray diffraction pattern of Glu ₂ Ca 4H ₂ O, Figure 4 shows GluK (anhydride), Glu ₂ Ca (anhydride)
shows the mutual solubility curve in an aqueous system.

Claims (1)

[Claims] 1. A novel glutamate represented by the formula Glu ₃ KCa·nH ₂ O (n=0 to 1). 2 Formula Glu ₃ characterized in that crystals are separated by crystallization from an aqueous solution containing glutamic acid, potassium and calcium, which is adjusted so that the potassium and calcium concentrations in the coexisting aqueous solution are between values B to C in FIG. A method for producing a novel glutamate represented by KCa·nH ₂ O (n=0 to 1). 3. A seasoning characterized by containing a novel glutamate represented by the formula Glu ₃ KCa·nH ₂ O (n=0 to 1).