@article{3062010,
    title = "In vitro digestibility of β-casein and β-lactoglobulin under simulated human gastric and duodenal conditions: A multi-laboratory evaluation",
    author = "Mandalari, G. and Adel-Patient, K. and Barkholt, V. and Baro, C. and Bennett, L. and Bublin, M. and Gaier, S. and Graser, G. and Ladics, G.S. and Mierzejewska, D. and Vassilopoulou, E. and Vissers, Y.M. and Zuidmeer, L. and Rigby, N.M. and Salt, L.J. and Defernez, M. and Mulholland, F. and Mackie, A.R. and Wickham, M.S.J. and Mills, E.N.C.",
    journal = "Regulatory Toxicology and Pharmacology",
    year = "2009",
    volume = "55",
    number = "3",
    pages = "372-381",
    issn = "0273-2300, 1096-0295",
    doi = "10.1016/j.yrtph.2009.08.010",
    keywords = "beta casein;  beta lactoglobulin;  pancreatin;  pepsin A;  phosphatidylcholine, allergy;  article;  controlled study;  densitometry;  digestion;  duodenum;  electrophoresis;  enzyme assay;  food safety;  in vitro study;  laboratory test;  nonhuman;  nucleotide sequence;  polyacrylamide gel electrophoresis;  priority journal;  protein hydrolysis;  reproducibility;  reversed phase high performance liquid chromatography;  simulation;  stomach, Allergens;  Animals;  Caseins;  Chromatography, High Pressure Liquid;  Digestion;  Duodenum;  Electrophoresis, Polyacrylamide Gel;  Humans;  Lactoglobulins;  Milk;  Pancreatin;  Pepsin A;  Reproducibility of Results;  Sodium Dodecyl Sulfate;  Stomach",
    abstract = "Initially the resistance to digestion of two cow's milk allergens, β-casein, and β-lactoglobulin (β-Lg), was compared using a "high-protease assay" and a "low-protease assay" in a single laboratory. The low-protease assay represents an alternative standardised protocol mimicking conditions found in the gastrointestinal tract. For the high-protease assay, both proteins were incubated with either pepsin or pancreatin and digestion monitored by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and reverse phase-high performance liquid chromatography. The low-protease assay involved gastroduodenal digestion in the presence or absence of phosphatidylcholine (PC). Both β-casein and β-Lg were susceptible to hydrolysis by pepsin and pancreatin in the high-protease assay. In contrast, the kinetics of β-casein digestion in the low-protease assay were slower, β-Lg being pepsin resistant. During duodenal digestion, β-Lg was gradually degraded and addition of PC slowed digestion. Subsequently, the reproducibility of the low-protease assay was assessed in 12 independent laboratories by visual assessment of the gels and densitometric analysis: the inter- and intra-laboratory variability was affected by sampling and electrophoresis method employed. The low-protease assay was shown to be reproducible. Future studies will extend these findings using a broader panel of proteins. © 2009 Elsevier Inc."
}