LACTITOL
Prepared at the 46th JECFA (1996), published in FNP 52 Add 4 (1996)
superseding specifications prepared at the 33rd JECFA (1988), published in
FNP 38 (1988). Metals and arsenic specifications revised at the 57th
JECFA (2001), An ADI 'not specified' was established at the 27th JECFA
(1983)
SYNONYMS Lactit, lactositol, lactobiosit, INS No. 966
DEFINITION
Chemical names 4-O-ß-D-Galactopyranosyl-D-glucitol
C.A.S. number 585-86-4
Chemical formula C12H24O11
Structural formula
Formula weight 344.32
Assay Not less than 95.0% and not more than 102.0% on the anhydrous basis
DESCRIPTION Sweet tasting crystalline powders or colourless solutions; crystalline
products occur in both monohydrate and dihydrate forms
FUNCTIONAL USES Sweetener, texturiser
CHARACTERISTICS
IDENTIFICATION
Solubility (Vol. 4)
Very soluble in water
Specific rotation (Vol. 4)
[alpha] 25, D: Between +13 and +15º (10% w/v aqueous solution)
Main peak in HPLC The main HPLC peak exhibited by the sample in the assay has the same
elution time as that of the lactitol standard
See Method of Assay
PURITY
Water (Vol. 4)
Crystalline products: Not more than 10.5% (Karl Fischer Method)
Solutions: Not more than 31% (Karl Fischer Method)
Sulfated ash (Vol. 4)
Not more than 0.1% on the anhydrous basis
Test 2 g (anhydrous basis) (Method I)
Chlorides (Vol. 4)
Not more than 100 mg/kg on the anhydrous basis
Test an amount of sample equivalent to 10 g of the anhydrous substance by
the Limit Test using 3.0 ml of 0.01N hydrochloric acid in the standard
Sulfates (Vol. 4)
Not more than 200 mg/kg on the anhydrous basis
Test an amount of sample equivalent to 10 g of the anhydrous substance by
the Limit Test using 4.0 ml of 0.01N sulfuric acid in the standard
Other polyols Not more than 2.5% on the anhydrous basis
See Method of Assay
Reducing sugars Not more than 0.1%
Proceed as directed under Reducing Substances (as glucose), Method II.
The weight of cuprous oxide shall not exceed 20 mg.
Nickel Not more than 2 mg/kg
See description under TESTS
Lead (Vol. 4)
Not more than 1 mg/kg
Determine using an atomic absorption technique appropriate to the
specified level. The selection of sample size and method of sample
preparation may be based on the principles of the method described in
Volume 4, “Instrumental Methods.”
TESTS
PURITY TESTS
Nickel Test solution
Dissolve 20.0 g of the substance to be examined in a mixture of equal
volumes of dilute acetic acid TS* and water and dilute to 100 ml with the
same mixture of solvents. Add 2.0 ml of a 1% w/v solution of ammonium
pyrrolidinedithiocarbamate and 10 ml of methyl isobutyl ketone. Mix and
allow the layers to separate and use the methyl isobutyl ketone layer.
Standard solution
Prepare three standard solutions in the same manner as the test solution
but adding 0.5 ml, 1.0 ml, and 1.5 ml, respectively, of a standard nickel
solution containing 10 mg/kg Ni, in addition to the 20.0 g of the sample.
Procedure
Set the instrument to zero using methyl isobutyl ketone as described for the
preparation of the test solution but omitting the substance to be examined.
Measure the absorbance at 232.0 nm using a nickel hollow-cathode lamp
as source of radiation and an air-acetylene flame.
METHOD OF Principle
ASSAY Determine lactitol as well as other polyols resulting as by-products during
the manufacture of lactitol by liquid chromatography. Principal by-product
polyols are the hexitols: sorbitol, mannitol, galactitol (dulcitol), and lower
polyols such as glycitols.
Apparatus
Liquid chromatograph with elevated temperature capability, differential
refractometric detector and 0.45 µm membrane filter before column.
Column
Aminex HPX 87 (calcium form) with dimensions 300 x 7.8 mm, or equivalent
column designed for carbohydrate analyses
Standards
Lactitol, sorbitol, mannitol
Eluent
Water (degassed)
Procedure
Equilibrate chromatography column to 85º. Adjust eluent flow rate through
column to 0.6 ml/min. Accurately prepare an aqueous solution of sample
about 40% by weight. Inject 10 µl of the 40% sample solution onto the
column. Record the chromatogram for peaks occurring at the retention time
of lactitol and thereafter.
Approximate retention times for lactitol and other polyols using the
recommended column are:
Lactitol 12 min
Ribitol 15 min
Erythritol 16 min
Mannitol 18 min
Galactitol 20 min
Sorbitol 21 min
For Assay, compare the sample response relative to the response of a
standard sample of lactitol of known purity.
For other polyols, measure the area of all peaks occurring between Lactitol
and Sorbitol. The sum of the areas of these peaks is not greater than 2.5 %
of the dry weight of the sample.
LACTITOL
SYNONYMS
DEFINITION
Chemical names
C.A.S. number
Chemical formula
Structural formula
Formula weight
Assay
DESCRIPTION
FUNCTIONAL USES
CHARACTERISTICS
IDENTIFICATION
Main peak in HPLC
PURITY
Other polyols
Reducing sugars
Nickel
TESTS
PURITY TESTS
Nickel
Test solution
Standard solution
Procedure
METHOD OF ASSAY
Principle
Apparatus
Column
Standards
Eluent
Procedure