Encapsulation of lipids as emulsion-alginate beads reduces food intake: a randomized placebo-controlled cross-over human trial in overweight adults.

The objective of this study was to investigate the efficacy of lipid emulsions encapsulated in calcium-alginate beads in reducing food intake and appetite sensations. These emulsion-alginate beads were ingested in a yogurt (active) and compared to an equienergetic yogurt containing nonencapsulated nutrients with comparable sensory properties (control) in a randomized placebo-controlled trial with crossover design. Thirty-three healthy overweight volunteers (mean age: 43 years; body mass index: 27.7 kg/m2; 14 male) received the 2 treatments. Test days started with a standardized small breakfast (t = 0) followed by an active or control yogurt (t = 90 minutes). Appetite sensations and gastrointestinal symptoms were monitored prior to and after consumption of the yogurt, and food intake was measured during ad libitum pasta meal consumption (t = 210 minutes). The hypothesis for this study was that delayed release of encapsulated lipids suppresses appetite sensations and reduces food intake. Food intake was significantly reduced with 51 ±â€¯20 kcal (213 ± 84 kJ) (P = .016) after intake of the active yogurt (770 ±â€¯38 kcal (3222 ± 159 kJ)) compared to the control (821 ±â€¯40 kcal (3435 ± 167 kJ)). The approach that we chose is promising to reduce food intake and could contribute to the development of an easy-to-use product for weight management.

Interfacial behaviour of biopolymer multilayers: Influence of in vitro digestive conditions.

Although multilayered emulsions have been related to reduced lipolysis, the involved interfacial phenomena have never been studied directly. In this work, we systematically built multilayers of whey protein and pectin, which we further subjected to digestive conditions, using two different techniques: droplet volume tensiometry to investigate interfacial rheology, and reflectometry to determine the amount of adsorbed material. Interfacial tension and dilatational rheology were linked to adsorption/desorption kinetics measured under static in vitro conditions. The interfacial tension and rheology of the multilayers was rather similar to those found for single whey protein layers, as well as their resistance to duodenal conditions and lipolytic components, which is explained by the rapid destabilisation of multilayers at neutral pH. Sequential adsorption of bile extract or lipase to pre-adsorbed films rapidly lowered the interfacial tension via co-adsorption and displacement, forming a viscoelastic film with low mechanical strength, and highly dynamic adsorption/desorption. When both were present, bile salts dominated the initial adsorption, followed by lipase co-adsorption and formation of lipolysis products that further lowered the interfacial tension, forming a complex interface (including biopolymers, bile salts, lipase, and lipolysis products), independent of pre-adsorbed biopolymer layers. Our study shows that the combination of drop volume tensiometry and reflectometry can be used to study complex interfacial behaviours under digestive conditions, which can lead to smart design of interfacial structures for controlled lipolysis in food emulsions.

Food-grade micro-encapsulation systems that may induce satiety via delayed lipolysis: A review.

The increasing prevalence of overweight and obesity requires new, effective prevention and treatment strategies. One approach to reduce energy intake is by developing novel foods with increased satiating properties, which may be accomplished by slowing down lipolysis to deliver substrates to the ileum, thereby enhancing natural gut-brain signaling pathways of satiety that are normally induced by meal intake. To develop slow release food additives, their processing in the gastrointestinal tract has to be understood; therefore, we start from a general description of the digestive system and relate that to in vitro modeling, satiety, and lipolytic mechanisms. The effects of physicochemical lipid composition, encapsulation matrix, and interfacial structure on lipolysis are emphasized. We give an overview of techniques and materials used, and discuss partitioning, which may be a key factor for encapsulation performance. Targeted release capsules that delay lipolysis form a real challenge because of the high efficiency of the digestive system; hardly any proof was found that intact orally ingested lipids can be released in the ileum and thereby induce satiety. We expect that this challenge could be tackled with structured o/w-emulsion-based systems that have some protection against lipase, e.g., by hindering bile salt adsorption and/or delaying lipase diffusion.