Bovine Colostrum to Prevent Absorption of Gluten

Inclusion Criteria: * Self-reported strict adherence to a gluten-free diet for at least 3 months. This may be a lifestyle choice, in solidarity with a child or other family/household member with celiac disease, because of non-celiac gluten sensitivity or because of celiac disease. * Willing to provide informed consent for all study procedures * Healthy volunteer according to the investigator assessment (history and physical exam) Exclusion Criteria: * Definite or probable gluten exposure during the 72 hours preceding each study intervention visit * Known active gastrointestinal disease. * Use of an oral digestive enzyme supplement during the 72 hours preceding each study intervention (challenge) visit. * History of severe symptomatic reactions to gluten or milk proteins * History of allergy to beef or meat * History of allergy to apple * Severe lactose intolerance * Any medication or medical condition which, in the opinion of the investigators, could adversely affect the patient's participation in the trial. * Allergy to PPI or other contraindication for PPI use (i.e history of interstitial nephritis attributed to PPI, history of PPI-induced diarrhea) * Pregnant women (according to pregnancy test)