Quantitative visualization study on the physical movement and gastric emptying of diced carrot particle in a transparent rat stomach-duodenum model

In this study, a transparent soft-elastic silicone rat stomach model was prepared to visualize the gastric movement and emptying of one individual diced carrot in a dynamic in vitro rat stomach system. The influences of the viscosity of solution medium, the pattern of gastric peristalsis and the extraction rate of the emptying pump on the location and gastric residence time of the carrot particle were examined. A proper medium viscosity could promote the emptying of the carrot particle. Compared to the combined actions of plate and roller, gastric residence time of the carrot particle was reduced from 32.3 to 19.8 min under the single plate compression. This time was also shortened from 34.8 to 12.3 min when the extraction rate of emptying pump was changed from 100 mL/min to 400 mL/min. Knowledge gained from this work is unique and may provide new insights for optimizing biomimic gastrointestinal models.

Use of Milk Fat/Cellulose Ether Emulsions in Spreadable Creams and the Effect of In Vitro Digestion on Texture and Fat Digestibility

This study investigated the texture properties and fat digestibility of new spreadable chocolate creams formulated with an emulsion composed of milk fat and a cellulose ether as a fat source. The spreadability was analysed at 20 °C and compared with a commercial spreadable cream formulated with palm fat. Structural changes in the creams after the in vitro oral and gastric digestion stages were evaluated; lipid digestibility was determined by titration with NaOH during intestinal digestion. Spreadability tests showed the spreads were similar. After oral digestion, the commercial spread showed an increase in extrusion force because of flocculation induced by saliva, an effect not observed in spreads with cellulose ether. Digestibility determination showed lower values for the reformulated spreads. Therefore, milk fat-cellulose ether based emulsions offer an alternative to achieve reformulated spreadable creams, with physical properties similar to those of commercial products but providing reduced fat content and lower lipid digestibility, without compromising the quality of the final product.

Digestibility of sulfated polysaccharide from the brown seaweed Ascophyllum nodosum and its effect on the human gut microbiota in vitro

Sulfated polysaccharides from marine algae exhibit various bioactivities with potential benefits for human health and well-being. In this study, the in vitro digestibility and fermentability of polysaccharides from the brown seaweed Ascophyllum nodosum (AnPs) were examined, and the effects of AnPs on gut microbiota were determined using high-throughput sequencing technology. Salivary amylase, artificial gastric juice, and intestinal juice had no effect on AnPs, but the molecular weight of AnPs and reducing sugar decreased significantly after fermentation by gut microbiota. AnPs significantly modulated the composition of the gut microbiota; in particular, they increased the relative abundance of Bacteroidetes and Firmicutes, suggesting the potential for AnPs to decrease the risk of obesity. Furthermore, the total SCFA content after fermentation increased significantly. These results suggest that AnPs have potential uses as functional food components to improve human gut health.

Digestion under saliva, simulated gastric and small intestinal conditions and fermentation in vitro of polysaccharides from the flowers of Camellia sinensis induced by human gut microbiota

In the present study, digestion under saliva, simulated gastric and small intestinal conditions and fermentation in vitro of polysaccharides from the flowers of Camellia sinensis (TFPS) by human gut microbiota were investigated. The results indicated that human saliva and simulated gastric and intestinal juices had no effect on TFPS, while TFPS could be utilized by human fecal microbiota, which was proved from the decreased molecular weight and lower content of total or reducing sugars after fermentation under anaerobic conditions. It was found that pH in the fermentation system decreased, and the production of short-chain fatty acids was significantly enhanced. Furthermore, in vitro fermentation of TFPS altered the composition of gut microbiota, specifically in elevating the ratio of Bacteroidetes to Firmicutes and enriching Prevotella. The present results suggest that TFPS has the potential to be developed as functional foods to modify gut microbiota.

Oil-in-water emulsions stabilised by cellulose ethers: stability, structure and in vitro digestion

Cellulose ether emulsions have good physical and oxidative stability and can delay in vitro lipid digestion. HMC emulsions inhibit lipolysis more than others and could enhance gastric fullness and satiety.

In vitro digestibility of highly concentrated methylcellulose O/W emulsions: rheological and structural changes

The changes in structure during the digestion of highly concentrated methyl cellulose (MC) O/W emulsions and of hydrated MC were investigated.