Four different formulations of phosphate glasses in the system P 2 O 5 -CaO-Na 2 O-TiO 2 were developed. Their physicochemical, morphologic, and structural evolution was analyzed during in vitro degradation in SBF (simulated body fluid) at 37°C up to 16 weeks. The results showed that the addition of TiO 2 into the glass system enhanced both the elastic modulus and the chemical durability of the glasses. Indeed, the elastic modulus increased from 66.6 to 75.95 GPa and the weight loss percentage diminished from 1.6% to 0.3% with the addition of 8 mol% TiO 2 . A uniform and superficial degradation mechanism could be observed throughout the dissolution time by means of environmental scanning electron microscopy (ESEM), inductively coupled plasma mass spectroscopy (ICP-MS), and Raman spectroscopy. The degradation process undergone by these glasses allows them to maintain their mechanical properties during the degradation process. Therefore, these materials offer an interesting choice for slowly resorbable materials in biomedical applications.

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The structural changes of two calcium-sodium metaphosphate glasses during its dissolution in simulated body fluid (SBF) have been analyzed by Fourier transform Raman spectroscopy (FT-Raman), scanning electron microscopy (SEM) and environmental scanning electron microscopy (ESEM). The results showed that no structural changes could be detected during the first week of dissolution. However, after approximately 4 weeks of dissolution the analysis of the glass surface revealed the presence of a thin orthophosphate layer. The elemental analysis of this layer by X-ray dispersive energy showed the presence of calcium phosphate ions, while almost no sodium was detected. The observation of the glasses by ESEM showed the formation of small crystals when the water vapor pressure of the chamber was decreased. This indicates that the layer analyzed by SEM and FT-Raman was related to a hydrated calcium phosphate layer.

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Cellular structure rather than cell wall firmness was found to impact cake crumb firmness. The new fast and automated tool for cake crumb structure analysis allows detecting quickly any change in cell size or homogeneity but also cell wall thickness and number of holes in the walls (openness degree). To obtain a softer crumb, it seems that options are to decrease the cell size and the cell wall thickness and/or to increase the openness degree. It is then possible to easily evaluate the effects of ingredients (flour composition, emulsifier …) or change in the process on the crumb structure and thus its softness. Moreover, this image analysis is a very efficient tool for quality control.