PMID- 35689606
OWN - NLM
STAT- MEDLINE
DCOM- 20221031
LR  - 20221102
IS  - 1944-7922 (Electronic)
IS  - 1060-3271 (Print)
IS  - 1060-3271 (Linking)
VI  - 105
IP  - 6
DP  - 2022 Oct 26
TI  - Lactose Concentration in Low-Lactose and Lactose-Free Milk, Milk Products, and 
      Products Containing Dairy Ingredients by High Sensitivity Enzymatic Method 
      (K-LOLAC), Collaborative Study: Final Action 2020.08.
PG  - 1617-1624
LID - 10.1093/jaoacint/qsac070 [doi]
AB  - BACKGROUND: The AOAC Stakeholder Panel on Strategic Food Analytical Methods 
      issued a call for methods in 2018 for the measurement of lactose in low-lactose 
      and lactose-free products under Standard Method Performance Requirement (SMPR(R)) 
      2018.009. Megazyme's Lactose Assay Kit (K-LOLAC) was reviewed and accepted as a 
      First Action Official MethodSM in 2020 (2020.08). OBJECTIVE: A collaborative 
      study was conducted to evaluate the to evaluate the reproducibility of AOAC 
      Official MethodSM2020.08 for the measurement of lactose concentration in 
      low-lactose and lactose-free milk, milk products, and products containing dairy 
      ingredients. METHOD: Samples are deproteinated and clarified by treatment with 
      Carrez reagents, and then free glucose is removed using a glucose oxidase and 
      catalase treatment system. Quantification of lactose is based on the hydrolytic 
      activity of beta-galactosidase, which hydrolyses lactose to glucose and galactose. 
      Any remaining free D-glucose is first measured using a hexokinase (HK)/glucose 
      6-phosphate dehydrogenase (G-6PDH)/6-phosphogluconate dehydrogenase (6-PGDH) 
      based assay procedure, and then beta-galactosidase is added to hydrolyze the lactose 
      in the same reaction vessel with concurrent measurement of the released 
      D-glucose. The samples analyzed included a number of lactose-free and low-lactose 
      milk samples, lactose-free infant formula, lactose-free milkshake, lactose-free 
      adult nutritional drink, lactose-free cream, and lactose-free cheese. RESULTS: 
      All materials had repeatability relative standard deviations (RSDr) <7%. The 
      reproducibility relative standard deviation (RSDR) varied from 3.8 to 14.9% with 
      seven of the 10 test samples having an RSDR of <10%. CONCLUSIONS: The Lactose 
      Assay Kit (K-LOLAC) meets the requirements for reproducibility set out under SMPR 
      2018.009. HIGHLIGHTS: The Lactose Assay (K-LOLAC) is a robust, simple, and 
      reproducible method for analysis of lactose in foodstuffs and beverages.
CI  - (c) The Author(s) 2022. Published by Oxford University Press on behalf of AOAC 
      INTERNATIONAL.
FAU - Ivory, Ruth
AU  - Ivory R
AUID- ORCID: 0000-0003-2281-2045
AD  - Megazyme, Bray Business Park, Southern Cross Rd, Bray A98 YV29, Ireland.
FAU - Mangan, David
AU  - Mangan D
AUID- ORCID: 0000-0002-8884-478X
AD  - Megazyme, Bray Business Park, Southern Cross Rd, Bray A98 YV29, Ireland.
FAU - McCleary, Barry V
AU  - McCleary BV
AUID- ORCID: 0000-0002-7103-5759
AD  - Megazyme, Bray Business Park, Southern Cross Rd, Bray A98 YV29, Ireland.
LA  - eng
PT  - Journal Article
PL  - England
TA  - J AOAC Int
JT  - Journal of AOAC International
JID - 9215446
RN  - EC 3.2.1.23 (beta-Galactosidase)
RN  - EC 1.11.1.6 (Catalase)
RN  - X2RN3Q8DNE (Galactose)
RN  - IY9XDZ35W2 (Glucose)
RN  - EC 1.1.3.4 (Glucose Oxidase)
RN  - EC 2.7.1.1 (Hexokinase)
RN  - J2B2A4N98G (Lactose)
RN  - 0 (Phosphates)
RN  - EC 1.1.1.43 (Phosphogluconate Dehydrogenase)
SB  - IM
MH  - Adult
MH  - Animals
MH  - Humans
MH  - Infant
MH  - beta-Galactosidase
MH  - Catalase
MH  - *Dairy Products/analysis
MH  - Galactose
MH  - Glucose
MH  - Glucose Oxidase
MH  - Hexokinase
MH  - *Lactose/analysis
MH  - *Milk/chemistry
MH  - Phosphates
MH  - Phosphogluconate Dehydrogenase
MH  - Reproducibility of Results
MH  - *Food, Formulated/analysis
PMC - PMC9605773
EDAT- 2022/06/12 06:00
MHDA- 2022/10/29 06:00
PMCR- 2022/06/11
CRDT- 2022/06/11 09:03
PHST- 2022/01/18 00:00 [received]
PHST- 2022/05/17 00:00 [revised]
PHST- 2022/05/20 00:00 [accepted]
PHST- 2022/06/12 06:00 [pubmed]
PHST- 2022/10/29 06:00 [medline]
PHST- 2022/06/11 09:03 [entrez]
PHST- 2022/06/11 00:00 [pmc-release]
AID - 6605849 [pii]
AID - qsac070 [pii]
AID - 10.1093/jaoacint/qsac070 [doi]
PST - ppublish
SO  - J AOAC Int. 2022 Oct 26;105(6):1617-1624. doi: 10.1093/jaoacint/qsac070.