Low Lactose ERP - Review Book

AOAC SMPR ERPs - 2019 METHOD REVIEW FORM

Submission Date

2019-08-25 08:43:15

Name

Sean Austin

E-mail

sean.austin@rdls.nestle.com

Organization

Nestle Research

Title of Method

Determination of Lactose in Low-Lactose or Lactose Free Milk, Milk Products and Products Containing Dairy Ingredients

AOAC Candidate Method Number (e.g. ALN-01)

LAC-005

Applicable SMPR

2018.009

I. Summary of the Method

Samples are dissolved in water (0.1 - 0.5 g solid sample or 0.1 to 1g of liquid sample in 50 g of water). After further dilution (if needed), the samples are injected on to an HPAEC-PAD system which is set up with in-line dialysis before the column set. Lactose is quantified against a calibration curve prepared with aqueous solutions of lactose at concentrations between 0.1 – 40 mg/kg. The authors have only tested the method with a few reference materials:- NIST 1869a (infant formula) MUVA-CA-0904 (sodium caseinate)

II. Review of the Method Only 1. Does the applicability of the method support the applicability of the SMPR? If not, please explain what is missing.

MUVA-ML-2310 (UHT low-lactose milk) MUVA-ML-2311(UHT lactose-free milk)

And one commercial sample of lactose-free milk (from coop)

The number of matrices is somewhat limited – but the authors have requested extra time to make a more complete validation which I would recommend.

The method has potential to support the applicability of the SMPR

2. Does the analytical technique(s) used in the method meet the SMPR? If not, please specify how it differs from what is stated in the SMPR. 3. Are the definitions specified in the SMPR used and applied appropriately in the method? If no, please indicate how the terms are used.

The SMPR did not define any specific analytical techniques to be used. So yes.

The SMPR defines the analyte to be lactose, not lactose monohydrate and it requests units in mg/100g (not mg/kg)

The method is able to do all of this - the report would be easier to read and assess if the authors managed the units better.