Research On Corn Starch-Based Fat Mimetic:Preparation, Properties And Interactions With Myofibrillar

With the improvement of people’s consciousness, low-fat and fat-free food have become a vital way to better one’s dietary habits and raise the overall healthy level. Fat mimetic, simulating the physical and sensory properties of fat, can be assimilated by human body, while only provides low-level of energy or no energy at all. The present study researched the technology of using corn starch as the base material to produce fat mimetic, the structure, basic properties of corn starch fat memetic and it’s interactions with myofibrillar.First, to investigate the technology of corn starch-based fat mimetic, the concentration of substrate, addition of a-amylase, hydrolysis temperature and hydrolysis time were set as four constraint conditions and single factor experiments were conducted to study the influencing factor regarding to the hydrolysis degree of corn starch, based on which series of orthogonal tests were then done to further confirm the ideal process conditions:8%of starch seriflux,5.0U/g of enzyme, hydrolysis temperature of70℃for l5min. The final product was white powder with an DE value of2.85.As to the structure and properties of corn starch-based fat mimetic, SEM showed that in the presence of enzyme, holes appeared at the surface of starch particles which resulted in roughness and diminution of practical seize to5um, in the mean time, grooves at the surface and aggregation between particles were also observed. In addition, after hydrolysis, the emulsibility and water-holding capacity of the mimetic improved significantly (P<0.05), while emulsifying activity and stability showed a similar increase (P<0.05). At the DE value of2.85, the appear viscosity and the rotate speed of viscosimeter are in an inverse relationship,’shear thinning’phenomenon and ’pseudo plastic fluid’ properties became obvious.The study also investigated the use of corn starch-based fat mimetic with the DE value of2.85in emulsion-type sausage (15%of fat content). It appeared the mimetic can substitute50%of fat in low-fat sausage with15%fat content thus met the standard of high-fat emulsion-type sausage in market, proved by series of texture analysis and sensory tests.In the end, the interaction between corn starch-based fat mimetic and myofibrillar protein revealed that the emulsibility and foaming ability of myobrillar protein increased considerably while the gel strength remain relatively constant which indicated the fat mimetic can improve the functional properties of myofibrillar.