RATIONALE Two important factors can influence the proportions of gluten and starch that resist digestion: (1) enzyme availability and specificity and (2) the structural properties of the food.

Glutalytic, is a dietary supplement based on an enzyme preparation which effectively degrades gluten in vitro (Healey, Hall et al. unpublished). As it has also been found that the rate of wheat protein digestion can be increased in the presence of amylases (Smith, Pan et al. 2015), Glutalytic is also enriched with amylase to aid in starch digestion.

The structural properties of food are influenced by numerous factors including meal preparation practices. Two common practices that can influence nutrient availability differently are heating vs. refrigerating (e.g. oat porridge vs. soaked and refrigerated oats).

Bacillus subtilis DE111 can produce and secrete many enzymes, including proteases, which, if secreted into the environment of the digestive tract, could support digestion and, in particular, the digestion of gluten. However, it is not clear whether diet supplementation with DE111 is a physiologically viable approach in terms of probiotic survival in the gastrointestinal tract.

PURPOSE The aims of this study are to better understand the impact of each of these factors and whether supplementation with probiotic spores is a viable option.