Impact of Food Process and Mastication on Nutrient Bioavailability

This cross-over study (double 5x5 latin square design) includes 10 young healthy subjects (5 males, 5 females).These subjects are studied in two different situations: a situation of good chewing efficiency, and a situation of disturbed chewing. This second situation is simulated by the wearing an occlusal appliance interfering with chewing and experimentally leading to poor masticatory efficiency. The overall study is conducted in two distinct protocols. The first protocol "Food bolus" is dedicated to the study of the rheological properties of the food bolus including analysis of the release of amino acids and bioactive peptides (secondary objective). The second protocol "Bioavailability" is the study of the bioavailability of bioactive compounds target (main objective). Each volunteer participates in both protocols. The sessions, with or without occlusal appliance, are randomized individually for each subject. Each subject is his own control and confounding factors related to individual variability of mastication and the general functioning of the digestive tract are therefore minimized.

Meat model was pork (Longissimus dorsi). Meat was sliced 2 cm thick, and two types of cooking were applied: 10 min cooking at 75 ° C and 45 min cooking at 90 °C. Meat was presented to volunteers in the form of pre-calibrated cubes (2x2x2 cm) of about 7 g.

Protocol 1: Sampling for "food bolus" study This part of the study allowed a complete description of the physical / rheological properties of bolus after good or poor mastication of the pork meat cooked according to the 2 previously described conditions. The analysis of these properties is followed all along the chewing sequence, until bolus swallowing. For that, boli are collected at different moments during the sequence of mastication. Subjects stopped chewing when indicated by the experimenter, and spat out the entire bolus with the saliva. This protocol also allows the release of carnosine and amino acids from the meat matrix during mastication to be studied.

Protocol 2: Sampling for 'bioavailability' study The volunteers participated in five sampling days. The determination of the kinetics of appearance in peripheral blood of targeted bioactive compounds (carnosine, lycopene) as well as the release of all amino acids, is done after ingestion of a mixed meal (meat, tomato, pasta), under conditions of normal or poor chewing. Meal is prepared from 100 g of cooked meat (low cooking or high cooking meat), 40 g of tomato puree, 10 ml of olive oil, and 80 g of raw pasta. An additional meal containing calcium is tested in normal chewing condition with low cooking meat. Meals are tested on different days. These days are spaced by at least 7 days.

Inclusion criteria

• Men or women
• Women with contraception considered reliable by the investigator
• 20 ≤ age ≤ 30 years
• Weight: ≥ 50kg
• Good general health
• Normal biological balance
• Body mass index : 20 ≤ BMI ≤ 30
• Good oral and dental health
• Subjects having at least 28 teeth, tolerance for missing teeth if the number of functional units remains higher than or equal to 11, or if the number of metal rings does not exceed 4
• Subject whose dentition makes possible a stable Class I occlusion Angle to the molar level
• Subject considered healthy on clinical examination and medical examination
• Person who signed the information sheet and consent
• Person subject to a social security scheme

Exclusion criteria

• HCV or HIV positive Serology
• Biological assessment considered abnormal and not compatible with the study by the investigator.
• Pregnant or lactating
• medical or surgical history (judged by the investigator as not compatible with the study )
• People with neurological problems making atypical or dysfunctional swallowing (dysphagia ...)
• Medication may interfere with the results of the study ( muscle relaxants or psychotropic)
• Blood donation within 8 weeks prior to the start of the study
• Oral surgery in the previous 12 months
• Subjects in dental care or having undergone orthodontic treatment in the previous 3 years
• Subject suffering or having suffered in the last month of the teeth , gums or mouth in general
• People with pain during chewing, pain in the face , mouth , jaw muscles, or loud creaking joints
• person under guardianship or not subject to a social security scheme
• Refusal to sign the information sheet and consent
• Refusal to be registered with the National Volunteer File
• Person in exclusion period another study , or who have received more than €4,500 in the year following his participation in clinical trials
• vegetarian or vegan or person not liking meat, tomato puree or pasta 17 diet without pork 18 important alcohol ( > 2 drinks / day or 20 g alcohol / day for women and > 3 drinks / day for men ) .