Quantifying the differences in structure and mechanical response of confectionery products resulting from the baking and extrusion processes.

Extrusion has potential advantages over baking in terms of throughput, asset cost and flexibility. However, it is challenging to achieve through extrusion the "light, crispy" texture of a more traditional baked confectionery. This study compares and contrasts for the first time confectionery products produced through these two processes, i.e. baking and extrusion. The microstructural differences are measured using imaging techniques, i.e. Scanning Electron Microscopy (SEM) and X-Ray Tomography (XRT) whereas mechanical characterisation is used to highlight differences in the resulting mechanical properties. Crucial information is presented which shows that the two technologies result in different mechanical properties and microstructures, even if the level of porosity in the two products is kept constant. In addition, confectionery products whether they are produced through baking or extrusion, have irregular geometries. The latter makes mechanical characterisation a real challenge. Therefore this study also presents rigorous methods for measuring true mechanical properties such that meaningful and valid comparisons may be made. The accuracy of the chosen methodologies is verified through experiments using flat and tubular extruded geometries as well as testing the products in various directions. It was concluded that the manufacturing method and, in the case of extrusion, the initial moisture content influences the microstructure and mechanics of confectionery products, both of which have an impact on consumer sensory perception.

Impact of chickpea hummus on postprandial blood glucose, insulin and gut hormones in healthy humans combined with mechanistic studies of food structure, rheology and digestion kinetics.

Slowing the rate of carbohydrate digestion leads to low postprandial glucose and insulin responses, which are associated with reduced risk of type 2 diabetes. There is increasing evidence that food structure plays a crucial role in influencing the bioaccessibility and digestion kinetics of macronutrients. The aims of this study were to compare the effects of two hummus meals, with different degrees of cell wall integrity, on postprandial metabolic responses in relation to the microstructural and rheological characteristics of the meals. A randomised crossover trial in 15 healthy participants was designed to compare the acute effect of 27 g of starch, provided as hummus made from either intact chickpea cells (ICC) or ruptured chickpea cells (RCC), on postprandial metabolic responses. In vitro starch digestibility, microstructural and rheological experiments were also conducted to evaluate differences between the two chickpea hummus meals. Blood insulin and GIP concentrations were significantly lower (P < 0.02, P < 0.03) after the consumption of the ICC meal than the meal containing RCC. In vitro starch digestion for 90 min was slower in ICC than in RCC. Microscopic examination of hummus samples digested in vitro for 90 min revealed more intact chickpea cells in ICC compared to the RCC sample. Rheological experiments showed that fracture for ICC hummus samples occurred at smaller strains compared to RCC samples. However, the storage modulus for ICC was higher than RCC, which may be explained by the presence of intact cells in ICC. Food structure can affect the rate and extent of starch bioaccessibility and digestion and may explain the difference in the time course of metabolic responses between meals. The rheological properties were measured on the two types of meals before ingestion, showing significant differences that may point to different breakdown mechanisms during subsequent digestion. This trial was registered at clinicaltrial.gov as NCT03424187.

Modelling Processes and Products in the Cereal Chain.

In recent years, modelling techniques have become more frequently adopted in the field of food processing, especially for cereal-based products, which are among the most consumed foods in the world. Predictive models and simulations make it possible to explore new approaches and optimize proceedings, potentially helping companies reduce costs and limit carbon emissions. Nevertheless, as the different phases of the food processing chain are highly specialized, advances in modelling are often unknown outside of a single domain, and models rarely take into account more than one step. This paper introduces the first high-level overview of modelling techniques employed in different parts of the cereal supply chain, from farming to storage, from drying to milling, from processing to consumption. This review, issued from a networking project including researchers from over 30 different countries, aims at presenting the current state of the art in each domain, showing common trends and synergies, to finally suggest promising future venues for research.

A natural mutation in Pisum sativum L. (pea) alters starch assembly and improves glucose homeostasis in humans.

Elevated postprandial glucose (PPG) is a significant risk factor for non-communicable diseases globally. Currently, there is a limited understanding of how starch structures within a carbohydrate-rich food matrix interact with the gut luminal environment to control PPG. Here, we use pea seeds (Pisum sativum) and pea flour, derived from two near-identical pea genotypes (BC1/19RR and BC1/19rr) differing primarily in the type of starch accumulated, to explore the contribution of starch structure, food matrix and intestinal environment to PPG. Using stable isotope 13C-labelled pea seeds, coupled with synchronous gastric, duodenal and plasma sampling in vivo, we demonstrate that maintenance of cell structure and changes in starch morphology are closely related to lower glucose availability in the small intestine, resulting in acutely lower PPG and promotion of changes in the gut bacterial composition associated with long-term metabolic health improvements.