Brookfield LFRA Texture Analyzer - Manual (Page 21)

Brookfield Engineering Labs., Inc. Page  Manual No. M/05-370-B0507
PARAMETERS: HARDNESS Force necessary to attain a given deformation
CONSISTENCY Internal strength of bonds within a product
(Total Positive Area)
ADHESIVENESS Work necessary to overcome attractive forces
(Total Negative Area) between surface of the food and the materials
with which it comes into contact.
ADHESIVE FORCE Force required to “pull” probe from sample
(suction).
MODULUS Ratio of stress divided by strain during the first
compression cycle (e.g., the slope of the force:
deformation curve). It is representative of
sample rigidity.
RESULTS:. LOW-FAT FAT-FREE
BREAK LOAD (g) 122 223
HARDNESS (g) 122 227
CONSISTENCY (g.s) 1592.7 3199.9
ADHESION (g.s) -246.4 -522.6
ADHESIVE FORCE (g) -58 -112
MODULUS (g/s) 7.0 15.7
where: gs = work
CONCLUSIONS: Creaminess of samples was evaluated as a comparison between low-fat
and fat-free samples. Its calculation is thus a comparative measure be-
tween two samples, but does give good indication of the effect of formu-
lation on the protein:protein network and resulting gel set. Such a test
would be excellent both within the Quality and Development environ-
ments, where product matching as well as process control could be facili-
tated.
The modulus values formed are also considerably different where the
higher values of the fat-free fat product denote the firmer, more bound
consistency of the product. Note should be made, however, on the posi-
tioning of sample cursors, to ensure that a consistent portion of sample
curve is measured between all batches and samples within.
EMPIRICAL Test conditions which will affect results generated:
FACTORS: 1. Sample size
2. Sample age
3. Sample temperature
4. Base and edge effects
5. Sample container and/or test probe employed