Enhancement of intragastric acid stability of a fat emulsion meal delays gastric emptying and increases cholecystokinin release and gallbladder contraction

Abstract

RC. Enhancement of intragastric acid stability of a fat emulsion meal delays gastric emptying and increases cholecystokinin release and gallbladder contraction. Am J Physiol Gastrointest Liver Physiol 292: G1607-G1613, 2007. First published March 1, 2007; doi:10.1152/ajpgi.00452.2006.-Preprocessed fatty foods often contain calories added as a fat emulsion stabilized by emulsifiers. Emulsion stability in the acidic gastric environment can readily be manipulated by altering emulsifier chemistry. We tested the hypothesis that it would be possible to control gastric emptying, CCK release, and satiety by varying intragastric fat emulsion stability. Nine healthy volunteers received a test meal on two occasions, comprising a 500-ml 15% oil emulsion with 2.5% of one of two emulsifiers that produced emulsions that were either stable (meal A) or unstable (meal B) in the acid gastric environment. Gastric emptying and gallbladder volume changes were assessed by MRI. CCK plasma levels were measured and satiety scores were recorded. Meal B layered rapidly owing to fat emulsion breakdown. The gastric half-emptying time of the aqueous phase was faster for meal B (72 Ϯ 13 min) than for meal A (171 Ϯ 35 min, P Ͻ 0.008). Meal A released more CCK than meal B (integrated areas, respectively 1,095 Ϯ 244 and 531 Ϯ 111 pmol ⅐ min ⅐ l Ϫ1 , P Ͻ 0.02), induced a greater gallbladder contraction (P Ͻ 0.02), and decreased postprandial appetite (P Ͻ 0.05), although no significant differences were observed in fullness and hunger. We conclude that acid-stable emulsions delayed gastric emptying and increased postprandial CCK levels and gallbladder contraction, whereas acid-instability led to rapid layering of fat in the gastric lumen with accelerated gastric emptying, lower CCK levels, and reduced gallbladder contraction. Manipulation of the acid stability of fat emulsion added to preprocessed foods could maximize satiety signaling and, in turn, help to reduce overconsumption of calories. gastric emptying; lipid; magnetic resonance imaging CONSUMPTION OF PREPROCESSED foods high in added fat is steadily increasing in the developed countries. Fatty foods have high energy density and palatability but exert a relatively weak effect on satiation (compared calorie per calorie with protein and carbohydrate loads), which may encourage calorie overconsumption (5). This, in turn, may be one important factor contributing to the current epidemic of obesity in the Western population (38). Weight gain management rightly focuses on a healthy balanced diet, sensible portion sizes, and exercise. However, it would be desirable also to be able to maximize the satiating properties of fatty meals themselves. This could help to reduce postprandial hunger and, in turn, snacking, and it could also lead to improved design of slimming products.Manipulating the sense of satiety derived from a fatty meal requires knowledge of the various interactions between the gut and the brain (2,22,40). One of the main satiety mechanisms triggered by ingestion of fat is the release of...

Molecular and structural organization of lipids in foods: their fate during digestion and impact in nutrition

“…Furthermore, the shape of emptying curve was exponential for unstable meal instead of linear for stable emulsion. More CCK was released after ingestion of the acid stable meal (1095 ± 244 pmole min/L) than after acid unstable meal (531 ± 111 pmole min/L), inducing a greater gallbladder contraction and decreasing postprandial appetite (Marciani et al, 2007). In another study, authors confirmed that acid-stable meals quitted more rapidly the stomach than acid-unstable meals and once in the duodenum lipids would be hydrolyzed more rapidly because of the higher surface area available for lipase/colipase complex (Marciani et al, 2009).…”

“…The choice of the surfactant is a key to control for the stability of an emulsion in the gastric environment. For example Tween 60 (E491, polyethoxy ethylene sorbitan monostearate) or Span 80 (E494, sorbitan monooleate) can be used to produce respectively acid-stable or unstable emulsions (Marciani et al, 2007) with similar droplet size (3.6 mm). Those emulsions were incorporated into a complete meal (500 ml, 675 kcal, 50 g lipids) and 5 h after their ingestion, subjects ingested 500 ml of a rehydrated vegetable soup (460 kcal, 12.5 g fat).…”

Improving Nutrition Through the Design of Food Matrices

“…A sustained reduction in daily calorie consumption could prevent or reduce this long term weight gain in a large proportion of the population, and thus to reduce the incidence of obesity and associated health problems. Fatty foods have high-energy density and palatability but exert a relatively weak effect on satiation (compared calorie per calorie with protein and carbohydrate foods), which may encourage calorie over-consumption (Marciani et al, 2007). Lowering energy density of foods can decrease energy intake independent of macronutrient content and palatability.…”

Human Gastric Simulator (Riddet Model)

“…Signifi cant efforts have been made during the last decade to better understand the overall functioning of the human stomach and to develop a new generation of in vitro models of enhanced biochemical and mechanical relevance (Boulby et al 1999 ;Faas et al 2002 ;Kunz et al 2005 ;Goetze et al 2007Goetze et al , 2009Kwiatek et al 2006 ;Marciani et al 2001aMarciani et al , 2007Marciani et al , 2012Marciani 2011 ;Schwizer et al 2002Schwizer et al , 2006Steingoetter et al 2005 ;Treier et al 2006 ;Mackie et al 2013 ). More notably among those models are the TNO and DGM systems discussed in the previous sections.…”