<p>Color, determined by tristimulus colorimeters, and related structural properties, i.e., microstructure, surface rheology, and bulk rheology, of cured porcine meat batters were studied.<p>Effects of various processing factors (such as, temperature, air pressure during chopping, and cutter type) on changes in color of porcine lean meat batters (PLMBs) during processing were characterized, analyzed, and predicted using graphical analysis, kinetic analysis, and mathematical modeling respectively. "Air pressure during chopping" had the greatest overall effect on color. The effect of "cutter type" was intermediate and that of "respiratory and proteolitic enzyme inhibitors" the least. Lightness (L*) values for different time-temperature combinations during heating of PLMBs could be closely predicted using the constructed mathematical model.<p>A study on the mechanism responsible for changes in (L*) of PLMBs during processing and subsequent storage at 15°C was performed. The extent and behavior of air entrapped within the PLMBs could explain the increase in their (L*) during chopping (phase 1), and during the first stage of a subsequent storage at 15°C until 24 h (phase 2). "Alterations in absorption traits" was found to be the main event responsible for the decrease in (L*) during the second stage of phase 2.<p>Apparent surface dilational viscosity of the surface of PLMB dispersions was determined by single compression experiments. Evidence for its profound influence on the behavior of the entrapped air bubbles during phase 2 were provided using microstructural techniques, and an emulsifier (glycerol lacto palmitate) as a probe.<p>The influences of the factors "formulation of the batter" and "entrapped air" on the color, rheology, and fracture of some porcine batters were investigated. Both factors had marked effects on the behavior of raw porcine batters' color during processing. The color of the cooked batters, however, was far less affected by the two factors. A qualitative explanation for these findings, on the basis of the balance between the scattering (mainly influenced by, e.g., entrapped air and added porcine back fat), and absorption characteristics (mainly influenced by the amount and state of myoglobin) of the batter systems, was possible. The effects of the two factors on the rheology and fracture of the cooked batters were studied using uniaxial compression. Added water, porcine back fat, and entrapped air bubbles caused a decrease in the modulus of deformability. Addition of the last two to the the PLMBs caused decrease in some fracture parameters. The results were analyzed on the basis of the "composite material" theory.
|Qualification||Doctor of Philosophy|
|Award date||6 Apr 1990|
|Place of Publication||S.l.|
|Publication status||Published - 1990|
- meat products
- animal products