British Journal of Nutrition

Full Papers


Effect of intragastric acid stability of fat emulsions on gastric emptying, plasma lipid profile and postprandial satiety

Luca Marciania1, Richard Faulksa2, Martin S. J. Wickhama2, Debbie Busha3, Barbara Picka3, Jeff Wrighta3, Eleanor F. Coxa4, Annette Fillery-Travisa2a5, Penny A. Gowlanda4 and Robin C. Spillera1 c1

a1 Wolfson Digestive Diseases Centre, Queen's Medical Centre, Nottingham University Hospitals, University of Nottingham, Nottingham NG7 2UH, UK

a2 Model Gut Platform, Institute of Food Research, Colney, Norwich NR4 7UA, UK

a3 Division of GI Surgery, Queen's Medical Centre, Nottingham University Hospitals, University of Nottingham, Nottingham NG7 2UH, UK

a4 Sir Peter Mansfield Magnetic Resonance Centre, School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, UK

a5 Centre for Research and Dissemination,, 39 Harvey Lane, Norwich NR7 0BZ, UK


Fat is often included in common foods as an emulsion of dispersed oil droplets to enhance the organoleptic quality and stability. The intragastric acid stability of emulsified fat may impact on gastric emptying, satiety and plasma lipid absorption. The aim of the present study was to investigate whether, compared with an acid-unstable emulsion, an acid-stable fat emulsion would empty from the stomach more slowly, cause more rapid plasma lipid absorption and cause greater satiety. Eleven healthy male volunteers received on two separate occasions 500 ml of 15 % (w/w) [13C]palmitate-enriched olive oil-in-water emulsion meals which were either stable or unstable in the acid gastric environment. MRI was used to measure gastric emptying and the intragastric oil fraction of the meals. Blood sampling was used to measure plasma lipids and visual analogue scales were used to assess satiety. The acid-unstable fat emulsion broke and rapidly layered in the stomach. Gastric emptying of meal volume was slower for the acid-stable fat emulsion (P < 0·0001; two-way ANOVA). The rate of energy delivery of fat from the stomach to the duodenum was not different up to t = 110 min. The acid-stable emulsion induced increased fullness (P < 0·05), decreased hunger (P < 0·0002), decreased appetite (P < 0·0001) and increased the concentration of palmitic acid tracer in the chylomicron fraction (P < 0·04). This shows that it is possible to delay gastric emptying and increase satiety by stabilising the intragastric distribution of fat emulsions against the gastric acid environment. This could have implications for the design of novel foods.

(Received January 08 2008)

(Revised June 12 2008)

(Accepted June 16 2008)

(Online publication August 05 2008)


c1 Corresponding author: Professor Robin C. Spiller, fax +44 115 9422232, email


Abbreviations: AUC, area under the curve; EPI, echo-planar imaging; t50 %, time to empty half of the meal volume from the stomach