Processing Apples to Puree or Juice Speeds Gastric Emptying and Reduces Postprandial Intestinal Volumes and Satiety in Healthy Adults

BACKGROUND: Whole apples produce greater satiety than processed apples, but the underlying mechanisms remain unclear.

OBJECTIVE: Our aim was to assess the intragastric processing of apple preparations and the associated small and large bowel contents using MRI.

METHODS: An open label, 3-way crossover, randomized, controlled trial. Eighteen healthy adults (mean ± SD age, 25 ± 4 y; BMI, 22.7 ± 3.5 kg/m2) underwent serial MRI scans on 3 occasions separated by 7 d, after consumption of isocaloric (178 kcal) portions of either whole apples, apple puree, or apple juice. Gastric emptying, small bowel water content (SBWC; primary endpoint), were measured at baseline and at 45 min intervals (0-270 min) postmeal ingestion. Fullness and satiety were also assessed at each time point. Treatment effects between groups were analyzed using ANOVA.

RESULTS: Gastric emptying half-time (GE t50) was greater (P < 0.0001) after participants consumed whole apple (mean ± SEM), 65 (3.3) min compared with when they consumed apple puree (41 [2.8] min) or apple juice (38 [2.9] min), times that did not differ. Postprandial area under the curve (AUC) (135-270 min) SBWC was also greater for whole apples than puree (P = 0.025) and juice (P = 0.0004) but juice and puree did not differ. AUC for fullness and satiety (0-270 min) postingestion was also greater (P = 0.002 and 0.004, respectively) for whole apple compared with juice but juice and puree did not differ.

CONCLUSIONS: Gastric emptying is slower after whole apple consumption causing a greater sensation of fullness and satiety than puree or juice in healthy adults. Whole apples increased small bowel and colonic contents during the later phase of the study which may be relevant for subsequent food consumption.This study was registered at clinicaltrials.gov as NCT03714464.