Approval/authorization  for use of 2-ethyl -5-methylpyrazine , isopentylamine  and 
magnesium  silicate  as food additive s  
 
 
Purpose  
 
This activity is to newly designate  2-ethyl -5-methylpyrazine , isopentylamine  and 
magnesium silicate  as authorized food additive s.  
 
Under Article 10 of the Food Sanitation Law, food additives may be used or 
marketed only when they are authorized  by the Minister of Health, Labour and 
Welfare. Where standards for use of additives and/ or their compositional 
specifications are establis hed under Article 11 of the Law, those additives may be 
marketed only when they meet the standards and/or specifications.  
 
In response to a request  from the Minister, the Subcommittee on Food Additives 
under the Food Sanitation Committee which is establis hed under the 
Pharmaceutical Affairs and Food Sanitation Council has discussed the adequacy of 
the designation of the se substance s as food additives. Conclusion of the  
subcommittee is outlined as below.  
 
Conclusion from the subcommittee  
The Minister should  designate  2-ethyl -5-methylpyrazine , isopentylamine  and 
magnesium silicate,  based on  Article 10 of the Food Sanitation Law , as food additive s 
unlikely to  harm human health , and establish compositional specifications for the se 
substance s, based on  Article 1 1 of the Law (see Attachment s 1, 2 and 3 ).  
 
 
Attachment  1 
2-Ethyl -5-methylpyrazine  
 
 
Standard for use  
It shall  not be used for purposes other than flavoring.  
 
Compositional specifications  
Substance name    2-Ethyl -5-methylpyrazine   
Structural formula  
NNCH3
H3C
 
Molecular formula   C7H10N2 
Mol. Weight   122.17  
Chemical name , CAS number   2-Ethyl -5-methylpyrazine  [13360 -64-0] 
Content  2-Ethyl -5-methylpyrazine  contains not less than 95.0% of 
2-ethyl-5-methylpyrazine  (C7H10N2).  
Description   2-Ethyl -5-methylpyrazine  occurs as a colorless  to light yellow, transparent  
liquid having a characteristic  odor.    
Identification   Determine the infrared absorption spectrum of 
2-Ethyl -5-methylpyrazine , as directed in the Liquid Film Me thod under Infrared 
Spectrophotometry, and compare it with the Reference Spectrum.  Both spectra  exhibit 
absorption s having about the same intensity at the same wavenumbers . 
Purity    
(1) Refractive index   n
20
D: 1.491–1.501 . 
(2) Specific gravity   d
25
25: 0.960–0.970.  
Assay   Proceed as directed in the Peak Area Percentage Method in the Gas 
Chromatographic Assay under the Flavor Substance Tests. Use operating conditions ( 1). 
Use a silicate -glass capillary tube (0.25 –0.53 mm in internal diameter and 30 –60 m in 
length ) coated with  a 0.25–1 m thick layer of polyethylene glycol for gas 
chromatography.   
 
 
Reference Spectrum  
 
2-Ethyl -5-methylpyrazine  
 
  
 
 
Attachment 2 
Isopentylamine  
 
 
Standard for use  
It shall  not be used for purposes other than flavoring.  
 
Compositional specifications  
Substance name   3-Methyl -1-butanamine , Isopentylamine, Isoamylamine  
Structural formula  
NH2
CH3H3C
 
Molecular formula   C5H13N 
Mol. Weight   87.16 
Chemical name , CAS number   3-Methylbutylamine  [107-85-7] 
Content Isopentylamine  contains not less than 98.0% of isopentylamine  (C5H13N).  
Description   Isopentylamine  occurs as a colorless to light yellow, transparent liquid 
having a characteristic  odor.    
Identification   Determine the infrared absorption spectrum of Isopentylamine , as 
directed in the Liquid Film Me thod under Infrared Spectrophotometry, and compare it 
with the Reference Spectrum.  Both spectra  exhibit absorption s having about the same 
intensity at the same wavenumbers . 
Purity    
(1) Refractive index   n
20
D: 1.405–1.411 . 
(2) Specific gravity   0.747–0.753.  
Assay   Proceed as directed in the Peak Area Percentage Method in the Gas 
Chromatographic Assay under the Flavor Substance Tests. Use operating conditions ( 2). 
Use a silicate -glass capill ary tube (0.25 –0.53 mm in internal diameter and 30 –60 m in 
length ) coated with  a 0.25–1 m thick layer of dimethylpolysiloxane  for gas 
chromatography.   
 
 
Reference Spectrum  
 
Isopentylamine  
  
 
 
Attachment 3 
 
Magnesium Silicate  
 
 
 
Standard for use  
It shall  not be used for uses other than a filtration aid for fats and oils . It shall be 
removed before the completion of the final product.  
 
Compositional specifications  
Substance name   Magnesium S ilicate  
Chemical name , CAS number   Magnesium s ilicate  [1343 -88-0]  
Definition  Magnesium Silicate  is a synthetic compound manufactured by the 
precipitation reaction between  sodium silicate and a soluble magnesium salt. Its 
composition is in a molar ratio of magnesium oxide to silicon dioxide of approximately 2 
to 5.    
Content   Magnesium Silicate , when calculated on the ignited basis, contains the 
equivalent of not less than 15.0% of magnesium oxide (MgO = 40.30 ) and the equivalent 
of not less than 67.0% of silicon dioxide (SiO 2 = 60.08 ).  
Description   Magnesium Silicate  occurs as a white, odorless, fine powder.   
Identification    
(1) Mix 0.5 g of Magnesium Silicate with 10 ml of dilute hydrochloric acid, and filter  
the mixture.  The filtrate  neutralize d with ammonia TS  responds to the test for 
Magnesium Salt  in the Qualitat ive Tests.   
(2) Prepare a bead by fusing a few crystals  of ammonium sodium hydrogenphosphate 
tetrahydrate on a platinum loop in the flame of a Busen burner. Place the hot, 
transparent bead in contact with Magnesium Silicate, and fuse again. An unfused lum p 
floats about in the bead, and when cooled, the bead  becomes opaque producing a 
web-like pattern.           
Purity    
(1) pH  7.0–11.0 (10% suspension).  
                                                   
 Japan has decided to permit magnesium  silicate  only as a filtration aid for fats and oils for the 
following reason:   Assuming that magnesium silicate was used only in table salt, estimates of the 
Japanese intake would exceed the ADI (0.3 mg/kg body weight/day ) established by the Japanese 
Food Safety Commission, based mainly on results of animal studies newly conducted in Japan  as 
well as data used in evaluation  by JECFA. This means that if it is permitted in table salt and other 
individual  food commodities at levels applied in other countries, the estimated total intake of this 
substance  by Japanese people is l ikely to gre atly exceed the ADI.   
 
 
(2) Water -soluble substances   Not more than 3%.  
Weigh accurately about 10 g of Magnesium Silicate in a beaker, add 150 ml of water, 
cover the beaker with a watch glass, and boil gently for 15 minutes. Cool, replenish the 
lost water, and allow the mixture to stand for 15 minutes. Filter through a filter paper 
for quantitative analysis (5C) by suction. If the  filtrate is turbid, repeat the filtration 
until the clear filtrate  is obtained. Add water to exactly 75 ml of the filtrate  to make 
exactly 100 ml. Refer the resulting solution to as solution A. Transfer exactly 50 ml of 
solution A into a tared platinum di sh, evaporate to dryness, and ignite for 3 hours at 
450–550ºC. Cool, and weigh the dish with the residue. Determine the residue.               
(3) Free alkali   Not more than 1% as NaOH.  
Add 2 drops of phenolphthalein  TS to 20 ml of solution A, and add 0.1  mol/L 
hydrochloric acid until the color of the solution disappears. The consumption of the 
hydrochloric acid is not more than 2.5 ml.  
(4) Fluoride   Not more than 10 g/g as F.  
Test Solution  Weigh exactly 2.0 g of Magnesium Silicate in a  polyethylene  beak er, 
add 60 ml of water, and stir the mixture for 15 minutes. Transfer  the suspension into a 
100-ml volumetric  flask, and add water to volume. Centrifuge  50 ml of the resulting 
suspension at 5,000 rpm for 15 minutes, transfer exactly 20 ml of the supernatan t into a 
polyethylene beaker, and add 10 ml of EDTA –tris TS.      
Control Solution   Weigh exactly  2.210 g of sodium fluoride, previously dried at 
110°C for 2 hours, in a polyethylene beaker, and dissolve in 200 ml of water with 
stirring. Transfer this solu tion into a 1,000 -ml polyethylene volumetric  flask, and add 
water to volume. Use the resulting  solution as the control stock solution . Store the stock 
solution in a polyethylene bottle. Prepare a control solution fresh before use by the 
following procedure . Place exactly 2 ml of the control stock solution in a 1,000 -ml 
volumetric  flask, and dilute with water to volume. Transfer exactly 5 ml of this solution 
into a 50 -ml volumetric  flask, and dilute with water to volume. Place exactly 20 ml of 
the second sol ution in a polyethylene beaker, and add l0 ml of EDTA –tris TS.  
Procedure   Measure  the electric potential s using a potentiometer connected to a 
reference electrode  and a fluoride ion electrode. The potential of the test solution is not 
less than that of the  control solution.  
(5)  Lead   Not more than 5.0 g/g as Pb.  
Test Solution   Weigh exactly 5.0 g of Magnesium Silicate into a beaker, add 50 ml of 
diluted hydrochloric acid solution (1 in 4), and stir. Cover with a watch dish, and boil 
gently for 15 minutes . Filter this solution by suction through a quantitative filter paper 
(5C) into a 50 -ml volumetric flask. Rinse the beaker and the residue on the filter paper 
with hot water, and add the filtrate and washings to the flask. Cool, and add diluted 
hydrochlori c acid solution (1 in 4) to make exactly  50 ml.   
Control Solution  To exactly 5 ml of Lead Standard Solution, add diluted 
hydrochloric acid (1 in 4) to make 100 ml.   
 
 
Procedure   Determine the absorbances of the test solution and control solution by 
flame a tomic absorption spectrophotometry using the operating conditions given below. 
The absorbance of the test solution  is not more than that of the control  solution.    
Operating conditions   
Light source : Lead hollow cathode lamp.    
Analytical line wavelength : 217 nm.  
Supporting gas: Air.  
Combustible gas: Acetylene.   
(6) Arsenic   Not more than 4.0 g/g as As 2O3. 
Test Solution   Add 5 ml of diluted hydrochloric acid (1 in 4) to 0.50 g of Magnesium 
Silicate, and heat gently while agitation until boiling. Cool immediately , centrifuge the 
mixture at 3,000 rpm for 5 minutes, and collect the supernatant. To the residue, add 5 
ml of diluted hydrochloric acid (1 in 4), agitate, centrifuge, and collect the washings. 
Add 10 ml of water to the residue, and proceed in the same manner. Combine all 
washings with the collected supernatant, and evaporate  to 5 ml by heating on a water 
bath.   
Apparatus  Use Apparatus B .   
Loss on Drying  Not more than 15% (105 ºC, 2 hours) .  
Loss  on Ignition  Not more than 15%  (dried sample, 900 –1000 ºC, 20 minutes ).        
Assay    
(1) Magnesium oxide   To accurately weighed about 1.5 g of Magnesium Silicate, add 
exactly 50 ml of 0.5 mol/L sulfuric acid, and heat on a water bath for 1 hour. Cool the 
mixture to room temperature , add methyl orange TS,  and titrate the excess acid with 1 
mol/L sodium hydroxide. Calculate the magnesium oxide content on the ignited basis.  
Each ml of 0.5 mol/L sulfuric acid = 20.15 mg of MgO       
(2) Silicon dioxide   Weigh accurately about 0.7 g of magnesium Silicate in a  beaker, 
add 20 ml of diluted sulfuric acid (3 in 100), and heat on a water bath for 90 minutes. 
Filter the supernatant by suction using a filter holder equipped with  a membrane filter 
(0.1 m pore size ). Add 10 ml of hot water to the beaker  containing the  residue, stir, and 
filter the supernatant by decantation through the membrane  filter. Wash the residue 
twice with 10 ml of hot water each time, and decant each supernatant  onto the filter. To 
the residue, add 25 ml of water, heat on a water bath for 15 mi nutes, and transfer the 
residue onto the membrane filter. Wash the residue with hot water until the washings 
no longer respond to test (1) for Sulfate in the Qualitative Tests. Heat the residue with 
the membrane filter in a platinum crucible to dryness, in cinerate, and ignite for 30 
minutes. Cool, and weigh (W 1 g). Moisten the residue with water, add 6 ml of 
hydrofluoric acid and 3 drops of sulfuric acid, evaporate  to dryness, and ignite for 5  
 
 
minutes. Cool, and weigh (W 2 g). Determine the silicon dioxide c ontent by the formula:  
Content (%) of silicon dioxide (SiO 2) =  
100basis ignitedtheon sampletheof)g( WeightW W 2 1
   
                  
 
 
Reagent  
Ammonium Sodium Hydrogenphosphate Tetrahydrate [K9013:2002]  White crystals  or 
granules. Easily effloresce in air.  
Identification  (1)  Add 1 ml of silver nitrate solution of (1 in 50) to 5 ml of a 
solution of  Ammonium Sodium Hydrogenphosphate Tetrahydrate (1 in 20). A yellow 
precipitate is produced. The precipitate dissolves when 1 ml of diluted nitric acid (1 in 3) 
or 5 ml of ammonia solut ion (2 in 5) is added.  
(2)  Add 1 ml of sodium hydroxide solution (1 in 10) to 5 ml of a solution of  
Ammonium Sodium Hydrogenphosphate Tetrahydrate (1 in 20), and heat. Ammonia is 
evolved.  
(3)  A solution of Ammonium Sodium Hydrogenphosphate Tetrahydrate  (1 in 20) 
responds to test (1) for Sodium Salt in the Qualitative Tests.  
Purity   Clarity  of solution   Clear (1.0 g, water 20 ml).