title: Comparison of endotoxin levels in cow's milk samples derived from farms and shops.
abstract: The observations on the protective effect of bacterial endotoxin in farm-derived cow's milk on childhood asthma and allergy are contradictory. The aim of this study was to determine the endotoxin levels in 'farm-derived whole raw' and 'processed shop' sources of cow's milk, and to test how the temperature and storing conditions might alter their endotoxin concentrations. Milk was collected from farms and shops. The level of endotoxin was measured by micro (gel-clot) Limulus amebocyte lysate test expressed as EU/ml. The concentration ranges of endotoxin were much higher and more widely scattered in the samples of whole raw farm milk than in the processed shop milk. Cold storage or heating increased the endotoxin concentrations in all samples of farm milk, but not in the processed shop milk. These results show that elevated levels of endotoxin in raw farm milk samples can occur from the cowshed or be formed during storage. In processed shop milk, storage does not cause any changes in the amount of endotoxin. Therefore, it is consistent that the handling and storage of raw milk alters the endotoxin concentrations, which may explain previous contradictory findings regarding the beneficial modulating effects on innate immunity toward allergy prevention in early childhood.
authors.affiliation: Division of Clinical Immunology, Institute of Internal Medicine, University of Debrecen, Debrecen, Hungary sipka@iiibel.dote.hu.
authors.forename: Sándor
authors.initials: S
authors.lastname: Sipka
authors.affiliation: Pharmaceutical Control and Development Laboratory, Budapest, Hungary.
authors.forename: Andrea
authors.initials: A
authors.lastname: Béres
authors.affiliation: National Research Institute of Radiobiology and Radio Hygiene, Budapest, Hungary.
authors.forename: Lóránd
authors.initials: L
authors.lastname: Bertók
authors.affiliation: Pharmaceutical Control and Development Laboratory, Budapest, Hungary.
authors.forename: Tamara
authors.initials: T
authors.lastname: Varga
authors.affiliation: Division of Clinical Nutrition, University of Kentucky, KY, USA.
authors.forename: Geza
authors.initials: G
authors.lastname: Bruckner
mesh_terms: D000818:Animals; D002417:Cattle; D004731:Endotoxins / Q000032:analysis*; D061353:Food Storage; D005615:Freezing; D006967:Hypersensitivity / Q000517:prevention & control; D008033:Limulus Test; D008892:Milk / Q000737:chemistry*; D061352:Pasteurization; D012034:Refrigeration; D013696:Temperature
chemical_list: D004731:Endotoxins
keywords: Allergy prevention; cow’s milk; endotoxin; temperature dependence