2.4.4. Texture analysis
Texture profile analysis (TPA) was performed in raw and cooked
samples at 4 ± 1 °C with a Texture Analyzer TA-XT2 (Stable Micro Systems,
Surrey, UK) following AmericanMeat Science Association (AMSA)
procedures (Claus, 1995). Cubic samples (1 × 1 × 1 cm) were cut from
burgers and subjected to a two-cycle compression test. Samples were
compressed to 70% of their original height with a cylindrical probe of
10 cm diameter at a compression load of 25 kg, and a cross-head
speed of 20 cm/min. Texture profile parameters were determined following
descriptions by Bourne (1978) and interpreted as follows. Hardness
(N) is the maximum force required to compress the sample;
cohesiveness is the extent to which sample could be deformed prior to
rupture (A2/A1), A1 being the total energy required for the first compression
and A2 the total energy required for the second compression; springiness
(mm) is the ability of the sample to recover its original shape after
the deforming force is removed; gumminess (N) is the force to disintegrate
a semisolidmeat sample for swallowing (hardness × cohesiveness)
and chewiness (N × mm) is the work needed to masticate the sample for
swallowing (springiness × gumminess).