The review outlines the increasing need to reduce trans fatty acids, and addresses the functionality issues of various trans free solutions through discussion of hydrogenation, interesterification, and fractionation, and their influence on fat crystallisation and solid fat content. Caution is urged not to focus solely on physiochemical aspects, but to approach trans free designing for specific food applications from a multidisciplinary angle. Examples of specific applications; margarines, shortenings and frying oils are given. The review also offers a glimpse into what the future trans free trends may hold.

Although many food products are essentially emulsions, interest in the structuring of oil-continuous emulsions (and in specific cases water-continuous emulsions) is intense, particularly to meet the continuing challenge of reducing the degree of saturates in food systems. Consequently, it is necessary to observe the effects of structurants and to examine their impacts on current food systems. This is especially the case where novel structuring materials are used to wholly or partially replace traditional structurants. A multidisciplinary approach is discussed encompassing traditional and novel mechanisms considered able to structure within low saturated fat-based systems and which in themselves could also have emulsification properties. The presence of interfacial compositions as in emulsions requires a crucial understanding of the interactions within these compositions for the creation of building blocks in oil or fat structuring. Where a co-surfactant structure may be used, together with novel structurants, for example, wax esters, phytosterols, it is necessary to understand how these may influence interfacial film thickness, strength and flexibility. Understanding how to measure mechanical visco-elastic properties of structurant interactions both in model and real time dynamic measurements will be necessary to account for diffusion, orientation and self-assembly mechanisms. This review discusses combining traditional techniques with novel structurant technology; developing and validating dynamic measurement techniques; and investigation of real systems as opposed to purely model systems.

Using macrobeam and microbeam techniques, we performed synchrotron radiation X-ray diffraction (SR-XRD) analyses of fat crystallization in water-in-oil (W/O) emulsion, in combination with DSC and polarized optical microscopic observation. Particular focus was on the crystallization of the fats around water droplets in the W/O emulsion systems using food emulsifiers of polyglycerol polyricinoleate (PGPR) alone (PGPR emulsion), and PGPR and monobehenoylglycerol (MB) (PGPR+MB emulsion). We obtained the following results: (1) macrobeam SR-XRD confirmed that adding MB promoted fat crystallization during cooling, (2) microbeam SR-XRD indicated that the lamellar planes of fat crystals near the water and oil interfaces are arranged almost parallel to the interface planes in both PGPR emulsion and PGPR+MB emulsion, and (3) adding MB resulted in the formation of tiny fat crystals because it promoted crystallization, which occurred both in the bulk oil phase and at the W/O interfaces. The present study is the first to apply microbeam SR-XRD to observe the microscopic features of fat crystallization in W/O emulsion, following fat crystallization in the oil droplets in the oil-in-water (O/W) emulsion (Arima, S.; Ueno, S.; Ogawa, A.; Sato, K. Langmuir 2009, 25, 9777-9784).

Fourier-transform absorption spectroscopy has been used in the laboratory to obtain absolute absorption coefficients a(v) in infrared bands of C1ONO2 in the 700-1800 cm -• spectral region. These data have been obtained over a temperature range (213-296 K) corresponding to stratospheric temperatures. The results are therefore applicable to retrievals of stratospheric C1ONO2 from remote-sensing observations. Room temperature absorption coefficients are some 25% larger than previously reported values, and large temperature dependences in the absorption coefficients have been observed. The/21 and/22 bands behave as simple fundamentals of a system which has low-energy vibrational or torsional modes, with little contribution from hot bands over the temperature range used. The intensity in the /22 Q branch increased by 53% over the temperature range 296-213 K. A similar increase was observed for the/24 Q branch, and significant hot-band features were seen in the /23, /24 spectral region. The /24 Q branch and the/22 Q branch were observed to obey the Beer-Lambert law over the range of pressure, temperature, absorber amount, and resolution employed. The absorption coefficients in the/24 Q branch and in the /22 band were modeled by equispaced absorption lines, each characterized by a central frequency, strength, lower-state energy, and pressure-broadened width.