Large deformation properties of β-lactoglobulin gel structures

摘要: Different gel structures formed by β-lactoglobulin dissolved in distilled water (12% w/w) at pH 3.0–7.5 have been investigated using tensile measurements large deformations. Gels 4–6 were opaque, whereas values below or above this range they transparent. The fracture properties showed variations over the studied. low brittle with strain and stress fracture, as opposed to those high pH, which rubber-like fracture. intermediate (pH 4–6) had an intermediate, near-constant, was, however, higher 5.5–6.0 than 4.0–5.2. specific energy resembled a maximum of 6 J/m2 6.0. 4.5, 5.5, 6.5 7.5 all notch-sensitive. opaque gels defined aggregate transparent fine-stranded gels. clearly there are differences between pH. demonstrated that structural within formed. non-linearity stress-strain curve was same for gels, r-shaped curves. curves almost linear. did not influence properties. Young's modulus two peaks, 3.5 6.0, coinciding where structure changes aggregated fine-stranded. also has elasticity may depend on strong, elastic areas network structure. Apart from shows behaviour storage modulus, G′, measured small deformations, but is slightly larger 3G′.