The aim of the study is to investigate whether the food matrix has an influence on the prebiotic efficacy (bifidobacteria growth) of chicory-derived Orafti® inulin in healthy adult volunteers. The main question it aims to answer is:

Does the food matrix influence the prebiotic effect of chicory-derived inulin in terms of stimulation of bifidobacteria in the gut microbiota Participants will receive one of three food items containing inulin or pure inulin dissolved in water daily for 10 days. The food items or pure inulin powder will deliver 10 g/d inulin split into two dosages of 5 g/d. They will provide stool samples before and at the end of the intake period. They will record any gastrointestinal sensations and bowel habits in a diary. Urinary samples will be collected at baseline and end of intervention for analysis of metabolites with Nuclear Magnetic resonance (NMR).

Inclusion Criteria:

• Volunteer is healthy at the time of pre-examination
• Volunteer is aged ≥ 18 to ≤ 65 years at the time of pre-examination
• Volunteer's BMI is ≥ 18,5 and ≤ 29,9
• Volunteer follows an average Western European diet
• Volunteer has a stool frequency of at least 3 bowel movements per week
• Volunteer is able and willing to comply with the study instructions
• Volunteer is suitable for participation in the study according to the investigator/study personnel
• Written informed consent is given by volunteer

Exclusion Criteria:

• No command of any local language
• Gastrointestinal disorders including irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) or other conditions that might affect the gut environment
• Food allergies or intolerances
• Vegetarians, vegans and/or extreme diets including high protein/fibre, ketogenic, intermittent fasting and/or carnivore
• Using drugs (e.g. antibiotics, aspirin, proton pump inhibitors) influencing gastrointestinal function (8 weeks before intervention)
• Use of laxatives and labelled pre- and probiotics in the previous 4 weeks before the beginning of intervention
• Clinically significant diabetes
• Volunteers currently involved or will be involved in another clinical or food study
• History of drug (pharmaceutical or recreational) or alcohol abuse.
• Has received bowel preparation for investigative procedures in the 4 weeks prior to the study
• Has undergone surgical resection of any part of the bowel.
• If participants are pregnant or are lactating