Mastication efficiency is defined as the efficiency of crushing food between the teeth and manipulating the resulting particles to form a swallowable food bolus. It is dependent on the orofacial anatomical features of the subject, the coordination of these anatomical features and the consistency of the food used during testing. Different measures have been used to indirectly quantify mastication efficiency as a function of children's age such as observations, food bolus characterisation, muscle activity measurement and jaw movement tracking. In the present review, we aim to describe the changes in the oral physiology (e.g. bone and muscle structure, teeth and soft tissues) of children and how these changes are associated with mastication abilities. We also review previous work on the effect of food consistency on children's mastication abilities and on their level of texture acceptance. The lack of reference foods and differences in testing methodologies across different studies do not allow us to draw conclusions about (1) the age at which mastication efficiency reaches maturity and (2) the effect of food consistency on the establishment of mature mastication efficiency. The effect of food consistency on the development of children's mastication efficiency has not been tested widely. However, both human and animal studies have reported the effect of food consistency on orofacial development, suggesting that a diet with harder textures enhances bone and muscle growth, which could indirectly lead to better mastication efficiency. Finally, it was also reported that (1) children are more likely to accept textures that they are able to manipulate and (2) early exposure to a range of textures facilitates the acceptance of foods of various textures later on. Recommending products well adapted to children's mastication during weaning could facilitate their acceptance of new textures and support the development of healthy eating habits.

This paper was published in Soft Matter as part of the Food Science web theme issue This Soft Matter theme issue explores fundamental interdisciplinary research into food science covering a variety of themes including food biophysics, food colloids and emulsions, and complex food structure. Please take a look at the full table of contents for this issue.

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The addition of water to lipsticks in the form of a water-in-oil emulsion is an attractive opportunity for cosmetics manufacturers to deliver hydrophilic molecules to the consumers, as well as improving the moisturizing properties. In this work, the effect of the emulsifier type and water content on the structural properties of the designed products was investigated. It has been shown that PGPR leads to smaller droplets than the other emulsifiers tested. This was attributed to the ability of PGPR to form elastic interfaces that slow the coalescence between droplets during the process. It was also observed that crystals of wax tend to form structures at the interface upon cooling that prevent coalescence during storage. These structures also prevent leakage of water into the continuous phase. No effect of the water content on the melting properties of the emulsions was observed. Upon addition of more than 10% water, softening of the material was measured, due to the overall decrease in solid content. Addition of crystalline material (hard paraffin) was successfully used to reinstate the material properties.

A range of methods, mainly X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC), have been used to characterise the polymorphism of fats in food products. As sugars present in chocolate have a significant XRD pattern, partially overlapping with the signal of cocoa butter, XRD cannot be applied directly to chocolate. In this paper, the XRD signal of a molten sample, similar to the one for pure sucrose, was subtracted from the signal of a solid sample of chocolate to remove the impact of the crystallised sugar. The XRD patterns obtained were compared with the pattern of cocoa butter cooled under the same conditions. Strong peaks were observed at similar inter lamellar d spacings showing that the polymorphic state of cocoa butter in processed chocolate could be obtained using this method. Numerical integration of the peaks also allowed quantification of the degree of crystallinity present in the system during a typical process. The accuracy of the method developed was found to be dependent on the (cocoa butter)/(sugar) ratio in the chocolate used.