Menthol

Parameter                                                          Requirement                                                                                          Observation
Description                       Colorless, Hexagonal or needle like crystals, or infused masses                        Colorless, hexagonal, needle like crystals, Odor,

                                         or crystalline powder, Odor, pleasant and characteristic                                      Pleasant and characteristic
Solubility                          Very soluble in ethanol (95% v/v) and in ether, Freely soluble                              

                                         in light liquid paraffin, in glacial acetic acid and in volatile oil, Slightly                  Complies
                                         soluble in water.
Identification                      Infrared absorption spectrum of the sample in potassium bromide dispersion    Complies
(A)                                     is concordant with reference spectrum of menthol or with spectrum 
                                          obtained from the preparation of Menthol RS.
(B)                                     Sample on reaction with sulphuric acid and solution of vanillin                             Complies 
                                          in sulphuric acid products an orange-yellow color.Futher, additio of
                                          addition of water changes the color to violet.
(C)                                    When triturated the sample with camphor or  chloral hydreate                               Mixture Liquefies

                                          or phenol, the mixture liquefies.
Specific Optical                Not less than -49 and                                                                                             -49.8
Rotation                           Not more than -51
Acidity                              Filtrate on addition of methyl red solution 0.01 M sodium                                       Complies 
                                         hydroxide gives a yellow color.
Related                            In the Chromatogram obtained with test solution the sum of the                             Complies 
Substance                        areas of any secondary peaks in not greater than the area of the
                                         prinicipal peak obtained with refernce solution (a).
                                         Ignore any peak with an area less than the principal peak in the
                                         chromatogram obtained with colored than reference solution.
Appearnce                       Sample solutoin is not more opalescent standard OS4, and not more                     Complies
of Solution                        intensely colored than reference solution RS6.
Residue on                       N M T 0.05% w/w                                                                                                       0.02%
Evaporation
* Purity by GC                  L-Menthol  : N L T 99%                                                                                               99.37%
(In-House) 

 

Compliance statement :
In the opinion of the undersigned, the above referred sample complies / does not comply as per the I.P / B.P./E.P./U.S.P.