PRODUCTION CHALLENGES The road to achieving these goals, as might be expected, demands a great deal of expertise. For example, low-fat spreads typically suffer from instability problems. Then there’s post-production oil separation to contend with. And the usual adverse effects on mouth-feel with lower-fat products. In all, we identified seven production challenges: Figures 2a and 2b demonstrate the build-up of primary crystal bond structure and how the fat, if it is more or less brittle, squeezes out the water with mechanical treatment. The emulsifiers that are located at the surface between water- and oil phase cannot avoid this phenomenon. Only a combination of the right process parameters and fat composition can solve this problem. Free water is, therefore, not always an emulsifier problem. Figures 2a and 2c show the effect of crystallisation and the development of crystals and the formation of the crystal network. Mechanical treatment will break down the primary crystal bond structure and provide a smoother structure with plasticity mainly based on van der Waals forces (secondary crystal bond structure). Figure 2a: Primary crystal bond structure. Figure 2b: Free water after squeezing Figure 2c: Secondary crystal bond structure. CHALLENGE 1: OVERCOMING THE FAT LIMIT In normal water/oil emulsions, water droplets have exactly the same size, which makes it difficult to reduce fat content lower than the theoretical level of 25.4%. But, by utilising the combined benefits of two emulsifiers: Palsgaard® DMG 0298 and Palsgaard® PGPR 4175, water droplets of varying size can be created. This meant the emulsion could be much more closely packed (see Figure 1), enabling fat content to be dropped to as low as 10%. The team worked hard to determine the right balance of liquid oil and solid fat (“fat composition”) to ensure a smooth, stable product. CHALLENGE 2: BALANCING THE FAT COMPOSITION The next challenge to be addressed was a question of balance. When creating a low-fat spread, it is important that the fat composition contains more liquid oil than similar high-fat products, because the oil phase needs to cover more water droplets. If the fat phase contains too much solid fat, the smoothness of the product will disappear. Equally, if the emulsion contains too much palm stearin it will tend to become less stable in 10% low-fat spreads. Most likely, the reason is a higher level of brittleness during and after production. Figure 1: Water droplet size in a 10% spread made with Palsgaard® DMG 0298 and Palsgaard® PGPR 4175. Next up was the need to minimise oil separation and to ensure a rewarding mouth-feel for consumers hoping to still be able to enjoy a low-fat version of their favourite spread. Again, the two different types of emulsifiers that addressed Challenge 1 – Palsgaard® DMG 0298 and Palsgaard® PGPR 4175 – came to the rescue. Palsgaard® DMG 0298 is a monodiglyceride (E471) but atypical in comparison with many other mono-diglycerides as the fatty acid combination is mainly based on oleic acids. The unsaturated fatty acids offer better emulsification and emulsion stability for reduced and low-fat spreads compared with standard mono-diglycerides. Palsgaard® PGPR 4175 is made from polyglycerol polyricineolate (E476) but is more polymerised than normal PGPR types. It’s a co-emulsifier, so it only delivers the desired effect when used together with another type of emulsifier. In low-fat spreads, PGPR is exceptionally good at coating CHALLENGE 3: MINIMAL OIL SEPARATION, MAXIMAL MOUTH-FEEL water droplets, fat crystals and increasing viscosity in low-fat emulsions. Without PGPR, it is not possible to make the very low fat spreads. Palsgaard® PGPR 4175 is, therefore, necessary for stabilising the 10% low fat spread as it helps avoid fluctuations during the production process and reduces the amount of rejected product. Palsgaard® PGPR 4175 is neutral in both taste and smell and is thus a unique non-flavour component. CHALLENGE 4: REDUCING OILING-OUT Products that contain a high proportion of liquid oil, such as the oil phase in low-fat spreads, also carry a high risk of oiling out. What we needed therefore, was an effective oil absorber. The answer, it turned out, was to use another Palsgaard product, an oil binder called Palsgaard® 6118. Functionally, Palsgaard® 6118 could easily do the job, and with hydrogenated products already declared undesirable, the fact that it’s based on non-hydrogenated vegetable fats made it a perfect fit. CHALLENGE 5: MINIMISING WATER SQUEEZE-OUT For reduced and low fat spreads, with their comparatively high water content, the water phase can negatively affect the taste and
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