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The digestive system is vital to the human body. Over many decades, scientists have been investigating the food breakdown mechanisms inside the stomach through in vivo human and animal studies and in vitro experiments. Due to recent improvements in computing speed and algorithm development, computational modelling has become a viable option to investigate in-body processes. Such in silico models are more easily controlled to investigate individual variables, do not require invasive physical experiments, and can provide valuable insights into the local physics of gastric flow. There is a huge potential for numerical approaches in stomach modelling as they can provide a comprehensive understanding of the complex flow and chemistry in the stomach. However, to make sure the numerical methods are accurate and reliable, rigorous verification and validation are essential as part of model development. A significant focus of this thesis was on verifying and validating the numerical modelling approaches pertinent to stomach modelling

The objective of this study was to investigate the peptidome of a red tide forming species Noctiluca scintillans based on mass-spectrometry (MS) analysis. N. scintillans cells were collected at the initiation and peak phases of its bloom. Peptides were extracted by ultrafiltration with cutoff of 10 and 3 kDa in acidic condition. Optimal mass spectra were generated after purification with C18 column. MS analysis and peptide identification was undertaken by Linear Trap Quadropole (LTQ) Velos MS/MS instrument. Using this method, 239 and 332 peptide sequences from the samples collected at the initiation and peak phases of N. scintillans bloom were identified, respectively. These sequences were classified and they were affiliated to 68 and 93 groups of precursor proteins, respectively, at the initiation and peak phases, with a compositional dissimilarity of 49.5%. Meanwhile, majority of the peptides were conjectured to come from contents digested by N. scintillans. Thirty-three groups of precursor proteins were detected at both phases. These peptides involved in various intracellular physiological activities, most of them responsible for functions of digestion activities such as oxidoreductase activity, catalytic activity, hydrolase activity and cofactor/ion binding. The compositions of precursor proteins, molecular weights, functions and cell compartments of the obtained peptides were quite different between two bloom stages. This is the first attempt to study peptidomics of N. scintillans, which provide important information on the functional studies of peptidomics in N. scintillans, especially food digestion and dietary protein utilization, as well as their relationship with bloom development.

29th International Conference of the European-Federation-of-Food-Science-and-Technology (EFFoST) -- NOV 10-12, 2015 -- Athens, GREECE, WOS: 000395217000007, Background: In vitro digestion models show great promise in facilitating the rationale design of foods. This paper provides a look into the current state of the art and outlines possible future paths for developments of digestion models recreating the diverse physiological conditions of specific groups of the human population. Scope and approach: Based on a collective effort of experts, this paper outlines considerations and parameters needed for development of new in vitro digestion models, e.g. gastric pH, enzymatic activities, gastric emptying rate and more. These and other parameters are detrimental to the adequate development of in vitro models that enable deeper insight into matters of food luminal breakdown as well as nutrient and nutraceutical bioaccessibility. Subsequently, we present an overview of some new and emerging in vitro digestion models mirroring the gastro-intestinal conditions of infants, the elderly and patients of cystic fibrosis or gastric bypass surgery. Key findings and conclusions: This paper calls for synchronization, harmonization and validation of potential developments in in vitro digestion models that would greatly facilitate manufacturing of foods tailored or even personalized, to a certain extent, to various strata of the human population. (C) 2016 Elsevier Ltd. All rights reserved., European Federat Food Sci & Technol

Story of Pavlov’s studies on food digestion including his Nobel Prize in 1904 are presented. Some new ideas and concepts are also viewed based on 3th International Conference on Food Digestion held in Wageningen (the Netherlands) in 2014.

High blood glucose and,insulin concentrations, even if within the normal range, are associated with an increased risk to develop type 2 diabetes and cardiovascular diseases. Dietary carbohydrates are the main determinants of blood glucose levels in the postprandial period; therefore, the effects of dietary carbohydrates on human health are strongly related to their rate of digestion in the small intestine. This has raised much interest on food properties able to retard carbohydrate digestion and absorption. This review is focused to examine food properties which influence carbohydrate digestion in order to predict their potential influence on health markers. Among them, it is worth to underline the role of viscosity, the physical form of the food, cooking methods and processing, the type of starch (amylose or amylopectin), the presence of anti-nutrients and the amount of fiber, fat, and proteins. In this respect particularly relevant is the type of starch present in the food, since amylose is slowly digested by intestinal alpha-amylases while the digestion of amylopectin is faster. However, the food component that has the strongest impact on digestion and absorption of dietary carbohydrates is dietary fiber that modulates the postprandial glucose rise by multiple mechanisms. In fact, dietary fibers may increase ingesta viscosity, thus delaying the gastric emptying time and slowing both carbohydrate digestion and the rate of glucose transport to enterocytes. In addition, they can influence the composition of the gut microbiota and induce the production of short-chain fatty acids that beneficially affect glucose and lipid metabolism. In short, the knowledge of food characteristics able to retard carbohydrate digestion and absorption in the intestine can help modify food properties with the aim of improving their functionality. (C) 2015 Elsevier Ltd. All rights reserved.

© 2016 Institute of Food Technologists®. Food digestion is a complex, multiscale process that has recently become of interest to the food industry due to the developing links between food and health or disease. Food digestion can be studied by using either in vitro or in vivo models, each having certain advantages or disadvantages. The recent interest in food digestion has resulted in a large number of studies in this area, yet few have provided an in-depth, quantitative description of digestion processes. To provide a framework to develop these quantitative comparisons, a summary is given here between digestion processes and parallel unit operations in the food and chemical industry. Characterization parameters and phenomena are suggested for each step of digestion. In addition to the quantitative characterization of digestion processes, the multiscale aspect of digestion must also be considered. In both food systems and the gastrointestinal tract, multiple length scales are involved in food breakdown, mixing, absorption. These different length scales influence digestion processes independently as well as through interrelated mechanisms. To facilitate optimized development of functional food products, a multiscale, engineering approach may be taken to describe food digestion processes. A framework for this approach is described in this review, as well as examples that demonstrate the importance of process characterization as well as the multiple, interrelated length scales in the digestion process.

Digestion rates have been measured for brown trout (Salmo trutta Linn.) during summer, fall, winter and spring seasons on the Blacksmith Fork River, Utah. Exponential rates of digestion varied from a gradual rate of -0.2372 to an accelerated rate of -0.6808. Factors found to affect digestion rate most were water temperature and the amount of food in the stomach. The affect of temperature was not clearly isolated. However, the amount of food in the stomach, at the beginning of the digestion study, appeared to have the most pronounced effect. Four of the five digestion rate measurements, with high coefficients 'of determination, were highly correlated to changes in the amount of food in the stomach. A stomach capacity study was also conducted during the winter season. A comparison of the results of the present study with those of an earlier study conducted during the summer season exhibited two nearly parallel non-linear regression lines. The differences in stomach capacity ranged from only 0.02 cc at 170 mm fork length to 0.93 cc at 340 mm fork length. Throughout the 170 to 340 mm size range, stomach capacities were smaller in the present study than those reported in the earlier study. Although some differences in method of determining stomach capacity did occur, these differences should have led to larger stomach capacities in this study. Since season of collection was different, it is suspected that was largely responsible for these differences. Therefore, the results of the stomach capacity study indicate that stomach capacities can be expected to change between summer and winter seasons. However, these changes may not be significant.