Monosodium glutamate solution

To 100 ml of a solution containing 0.1M monosodium glutamate is added 17 ml of 1M HC1. What is the final pH, and which molecular forms are present ... 

Solution Monosodium glutamate has the following ionic structure and undergoes the following conversion to more protonated states ... 

Aqueous solutions of monosodium glutamate may be sterilized by autoclaving. Monosodium glutamate should be stored in a tight container in a cool, dry place. 

In the authors laboratory, an in vitro test was devised to evaluate the cryoprotective effect of any compound on fish protein. The test system consisted of carp actomyosin either in solution (in 0.6M KC1) or in suspension (in 0.05M KC1). By means of this system about 150 compounds were screened, out of which about 30 compounds were found to be markedly effective and another 20 compounds were found to be moderately effective. Among the former group, monosodium glutamate (MSG) was particularly outstanding. Additives were used at a concentration of 0.1-0.2M in the final mixture and the pH was adjusted to 7 before freezing (51,52,116,117,119,124,125,126). Similar studies have been done by other workers (60,127). 

Monosodium glutamate is formed by reacting purified glutamic acid with an appropriate amount of sodium hydroxide in an aqueous solution. Residual color is removed by a final treatment with activated carbon. 

Determination of the recognition thresholds of aqueous solutions of the umami tasting monosodium glutamate (MSG) and the salty tasting sodium chloride (NaCl), respectively, in the absence or presence of equimolar amounts of the alapyridaine enantiomers revealed that the detection thresholds of MSG (1.5 mmol/L) and NaCl (10 mmol/L) were 8 and 5 times lower when (+)-(5 )-alapyridaine was present 13). On the basis of these data it might be concluded that alapyridaine is a multivalent taste enhancer increasing the human sensitivity for sweetness, saltiness, and umami taste. 

Monosodium glutamate is an important metabolyte and flavoring agent. What pH should it produce in 0.010 M solution See K values in Example 2. 

Monosodium glutamate, or MSG, is the sodium salt of the amino acid glutamic acid. Its formula (with ions shown) is Na C5H3N04 . Calculate the concentration of the zwitterionic glutamic acid in a 0.010-m solution of MSG. Assume the molalities are equal to the activities. Hint See equation 5.21 andTable 5.1. 

FIGURE 28.3 Flow system for the simultaneous determination of MSG, GMP, and IMP. MSG, monosodium glutamate GMP, guanosine monophosphate, IMP, inosine monophosphate AC, acetate column BS, buffer solution D, detector PP, peristaltic pump qi, buffer solution flow rate (2.06 mL min 0 qi5 standard and sample solution flow rate (1.08 mL min 1) RC, reactor coil S, sample SS, standard solution SV, selection valve W, waste. (Reprinted from Talanta, 82, Acebal, C. C. et al.. Successive projections algorithm applied to spectral data for the simultaneous determination of flavor enhancers, 222-226, Copyright 2010, with permission from Elsevier.)... 

Monosodium L-glutamate [142-47-2] C HgNO Na H20 (mol wt 187.13) crystallizes from aqueous solution at room temperature as rhombic prisms. Its stmcture, as deterrnined by x-ray crystallography (6), indicates that the sodium ions are coordinated octahedraHy by four (3a and ly) carboxyl oxygen atoms and two water molecules as follows ... 

Monosodium L-Glutamate occurs as white, free-flowing crystals or crystalline powder. It is freely soluble in water, and is sparingly soluble in alcohol. The pH of a 1 20 aqueous solution is between 6.7 and 7.2. 

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