Investigating how the physical form of food affects the absorption of contained starch and carbohydrate by the gut

INTERVENTION: The uptake of 10 g lactulose and 5 g mannitol incorporated into (a) 50 g of uncooked extruded pasta pellets (mean diameter: 3.18 millmetre ) made of maize flour (b) 50 g of uncooked hydrated (1:2 w/w in water) powdered pasta pellets and (c) a control consisting of 50 ml of the two probe sugars dissolved in water. All of these interventions were mixed with 150 g of 'fruit sauce' containing 0.1 % Guar gum (Grindsted (Registered Trademark), DaniscoPvt Ltd, Australia), 0.3 % Xanthan (80 Mesh, ISXANT8.1, IngredientStop) and 0.02 % vanilla flavouring (Batch 181110, Zymus) and a standard volume of water. Lactulose and mannitol was determined by measuring their excretion in urine by high performace liquid chromatography (HPLC). These foods each were fed to 22 healthy female participants (screened by questionnaire) in random sequence at weekly intervals. The subjects were asked to empty their bladder every half‐hour over a six hour period. Venous blood was collected every half‐hour over four hours and thereafter at five and six hours for plasma blood glucose and plasma insulin determination. Comparisons of the temporal pattern of absorption of each of the two probe sugars sugar and the blood glucose values for six hours after consumption of each food with that of the control will provide an indication of the effect of processing on the rates of absorption of nutrients from the gut lumen. CONDITION: The absorption of carbohydrate from different food matrices PRIMARY OUTCOME: Quantification of nutrient uptake index (NUI) which represents the speed at which simple sugars are liberated from the food matrix into the lumen of the small intestine and absorbed by the mucosa. SECONDARY OUTCOME: A composite secondary outcome was to compare the rates of appearance of glucose and insulin in the systemic circulation with the rate of absorption of mannitol and lactulose to better quantify the differences in kinetics of active absorption from those of passive absorption ; INCLUSION CRITERIA: Female volunteers between the age of 20 and 40 years were screened by questionnaire for general medical health, gut health, ongoing consumption of medication, dietary supplements, dietary peculiarities and smoking. Inclusion criteria is as follows: (1) Participants were non‐smokers with no history of gastrointestinal diseases including recent gut infection evidenced by a recent history of abdominal pain, nausea, vomiting, diarrhea, passage of blood and mucus in stools. (2) Participants were not taking any ongoing prescription or OTC medication or multivitamins except for contraceptive pills. (3) The number of Standard alcohol drinks consumed per week were calculated from results of alcohol consumption in the questionnaire to ensure that participants did not exceed a moderate alcohol intake. (4) Participants did not have high levels of endogenously produced mannitol or lactulose in the urine.