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Galactooligosaccharides

Last updated

Name of the ingredient:

Galactooligosaccharides (AAN ID#142918)

Definition of the ingredient

Galactooligosaccharides (GOS) is produced from lactose by an enzymatic process using Β‑galactosidases from Papiliotrema terrestris or Neobacillus kokaensis. A lactase enzyme may be used to reduce the level of residual lactose. The final ingredient can be in powder, syrup, or easy drying syrup forms.

Molecular Formula: (C6H11O5)n

Chemical Structure:

Picture of the chemical structure of Galactooligosaccharides
Table 1. Ingredient specific requirements
Test Method reference Acceptance criteria

Description

Appearance

Visual

Syrup or powder

Colour

Visual

Clear (for syrup forms)

White (for powder form)

Characteristics

Dry matter (for syrup forms only)

ISO 6734/IDF 15

74 to 76%

Total moisture (for powder form only)

ISO 760, Karl Fischer

≤4%

Sulfated ash

NEN 6810; NEN-EN-ISO 5809

≤1.0% (on dry matter)

Nitrogen

ISO 8968-2/IDF 20-2 Kjeldahl

≤0.1%

Nitrite

ISO 14673-2/IDF 189-2

≤2 mg/Kg

pH (10% solution at 20°C)

NEN 3775

2.8 to 4.5

Identification

HPAEC-PAD

van Leeuwen et al., 2016[1]

Retention time of the main peak corresponds to the retention time of the GOS standard.

NMR

van Leeuwen et al., 2016[1]

Recorded 1H NMR spectrum must be in full agreement with the structure of GOS.

MALDI-TOF-MS

van Leeuwen et al., 2016[1]

Spectra must conform to the GOS standard.

Assay

Galactooligosaccharides (GOS)[2]

HPAEC-PAD[3]

≥57% (on dry matter)

Lactose

HPAEC-PAD[3]

≤30 % (on dry matter)

Glucose

HPAEC-PAD[3]

≤22% (on dry matter)

Galactose

HPAEC-PAD[3]

≤2.5% (on dry matter)

Glucose + Galactose (for powder forms only)

HPAEC-PAD[3]

≤7% (on dry matter)
Table 2. Incidental constituents
Test Method reference Acceptance criteria

Incidental metals and non-metals

Lead

ISO 17294, ICP-MS

Max. 0.16 mg/Kg

Arsenic

ISO 17294, ICP-MS

Max. 0.1 mg/Kg

Cadmium

ISO 17294, ICP-MS

Max. 0.005 mg/Kg

Mercury

ISO 17294, ICP-MS

Max. 0.006 mg/Kg

Nickel

ISO 17294, ICP-MS

Max. 0.03 mg/Kg

Cobalt

ISO 17294, ICP-MS

Max. 0.005 mg/Kg

Vanadium

ISO 17294, ICP-MS

Max. 0.005 mg/Kg

Microbiology

While substance manufacturers are encouraged to include limits for objectionable microorganisms, it is the product into which those substances are formulated that is subject to a legally binding set of criteria. The Therapeutic Goods Order No. 100 ‘Microbiological Standards for Medicines’ mandates that any finished product that contains the ingredient, alone or in combination with other ingredients, must comply with the microbial acceptance criteria set by Clause 11 of the Order.

Footnotes:

  1. van Leeuwen SS, Kuipers BJ, Dijkhuizen L, Kamerling JP (2016). Comparative structural characterization of 7 commercial galacto-oligosaccharide (GOS) products. Carbohydr Res 425:48-58. DOI:10.1016/j.carres.2016.03.006.
  2. GOS content is determined by calculation and the equation used is as follows:
    GOS wt% = 100% - (lactose wt% + glucose wt% + galactose wt%)
  1. HPAEC: Columns: Analytical anion exchange column - Thermo Dionex Carbopac SA10 (4 x 250mm), Guard anion exchange column - Thermo Dionex Carbopac SA10 (4 x 50mm); Mobile phase: Eluent A (125 mM sodium hydroxide solution), Eluent B (UHQ Water); Flow rate: 1.00 mL/min; Column temperature: 25°C; Retention times as follows:

Component

Retention time (min)

Galactose

5.690

Glucose

6.250

Lactose

8.450

Abbreviations

HPAEC-PAD: High performance anion-exchange chromatography coupled with pulsed electrochemical detection

ICP-MS: Inductively coupled plasma coupled with mass spectrometric detection

IDF: International dairy federation

ISO: International organisation for standardisation

MALDI-TOF-MS: Matrix-assisted laser desorption ionisation coupled with time-of-flight mass spectrometric detection

NEN: Nederlandse norm

NMR: Nuclear magnetic resonance spectroscopy

Product types