Ryszard Rezler

Emulsions stabilized using potato starch

Water binding in fat-in-water emulsions with native potato starch was investigated at the molecular level using the low-field nuclear magnetic resonance method. Analysis of relaxation time changes with temperature allowed determination of activation energy values for water molecules. Application of potato starch as an emulsifier required selection of an appropriate polymer content. Optimal water binding was recorded when emulsions contained 6 parts of potato starch per 10 parts of fat. Activation energy values of water molecule rotations were more than twice values in comparable gels. Emulsions were more stable than starch gels with the same polymer concentration in water. Comparison of fat-water emulsions demonstrated that use of porcine fat allowed development of emulsions in which water was more strongly bound.

Water binding analysis of fat-water emulsions

Low-field NMR was used for analysis of water binding in fat-in-water emulsions. Bovine fat was used and native potato starch was used as an emulsifying agent. Starch can be applied as an emulsifying agent although the starch content should not be lower than 0.17 g/g of water at fat concentrations in water amounting to 25%. Interactions of bovine fat with chains of starch exceeded the actions of water molecules with the polymer, leading to advantageous conformation changes. Bovine fat restricts the unfavourable influence of starch retrogradation. This, in turn, leads to a slowing of the syneresis process.