TABLE OF CONTENTS Soy proteins play important roles in many foodstuffs because of their nutritional values and their contribution to food texture. Soy proteins' texture can be influenced by their processing conditions.
The texture of soy protein can be measured by a sequence of tests and corresponding mechanical properties.
Measurement of mechanical properties of gels. A compression-decompression test was carried out by using a compression tester. The tester had a cylindrical plunger with a cross-sectional area of 0.25 cm 2. The tests were performed at 20 C. The plunger descended at a rate of 1.2 mm per minute. The following four measures were recorded:
Compression work. It is the mechanical work in each compression-decompression cycle.
Resiliency (RS). It is the ratio of decompression work versus compression work.
Compressibility ( CM) It is measured by the ratio of deformation versus the gel sample thickness.
Force. It is determined as the force at yield.
The compression-decompression tests are conducted at different levels until rupture. Specifically, four levels of compression load are used. They are small (S), medium (M), large (L), and rupture (R). They correspond to 15%, 30%, 60%, and 100% of rupture force.
Since there are four measures and each measure is recorded at four levels of compression loads, each protein gel sample test produces 16 observations of data.
Soy gel processing condition. ...
