Empty yeast cells are used as a new delivery system for flavor encapsulation. The flavor release mechanism from yeast cells is characterized using a series of analytical techniques, and limonene is used as a model representing a hydrophobic flavor. Furthermore, the thermal stability of the capsules was assessed. The characterization of the cell wall structure gives rise to the development of an empirical model explaining water adsorption as well as the desorption singularities observed on drying. The study of the rate of flavor release as a function of temperature and water uptake in the cell wall clearly demonstrated a particular behavior of the yeast cell wall permeability. Below a water activity around 0.7, no flavor release is permitted whereas release occurs above it. Surface analysis on dry or wet cells using atomic force microscopy is discussed.

A broth of dried scallop adductor muscles was prepared. Tasters appreciated the typical seafood, sweet, slightly umami taste of scallop, which is difficult to reproduce with common ingredients. Therefore, the broth was fractionated and, guided by multiple tastings, we isolated a sweet, umami, delicious fraction. This fraction contained glycine, alanine, and (R)-strombine ((R)-2-(carboxymethylamino)propanoic acid). (R) and (S)-strombine were prepared, and a sensory analysis with 47 judges demonstrated that the taste thresholds were 0.5 g/L for (R)-strombine and 0.7 g/L for (S)-strombine. The sensory attributes were described as salty and umami.

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The fracture behavior of 3 austenitic steels has been tested in liquid sodium on notched tensile specimens after pre-wetting in oxygenated sodium (200 wppm). Austenitic steels are shown to have decreasing crack propagation resistance in liquid oxygenated sodium for some experimental conditions. Crack initiation occurs after significant plastic deformation. Evidences of brittle fracture are observed on the fracture surface. The effect of impurities on LME susceptibility is estimated to be unlikely.

Starting from the pioneering work of Beremin, the classical Beremin-Weibull fracture probability’s model was extended recently to tackle with non-monotonic thermomechanical loadings. As a result of temperature effect on mechanical fields’ heterogeneity, an apparent temperature dependence of tile cleavage stress was also introduced to fit correctly the fragile to ductile transition. Considering the classical expression of the fracture probability, this extension consists in substituting the instantaneous opening stress by the maximum of the instantaneous opening stress versus cleavage stress ratio, this maximum being searched for previous active plastic time. This extended Beremin model was successfully applied to WPS tests experienced on low alloy ferritic steel compact tension specimens. Through this work, we aim at applying this approach to assess RPV structural integrity, assumed to be affected by a subclad flaw, during a simulated PTS event. The pressurized vessel is submitted to a thermal transient applied on the inner cladded surface. Considering a circumferential flaw, a two-dimensional elastic-plastic Finite Element calculation is performed. Therefore, the time evolution of elastic-plastic stress intensity factor KJ at the crack tip in base metal is calculated. Then, the time evolution of the cumulative fracture probability, as predicted by the extended Beremin model, is derived to evaluate the vessel integrity.

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