7.3.18 Physical measurements of the

7.3.18 Physical measurements of the products
7.3.18.1 Determination of the expansion index and bulk density of snack
basis products
By using a sliding calliper, the diameter of the extrudate was measured. For every
composition, 10 measurements were done. To achieve the expansion index, the
diameter of the extrudate (mm) was divided by the diameter of the die (mm).
Bulk density was measured in gram per liter. A pot with a volume of 5 l was weighed
and then filled with the extrudates and again weighed. This was done three times for
each composition. The expansion index and the bulk density describe the expansion of
the snack basis products.
7.3.18.2 Determination of the spreading factor of the biscuits
By using a sliding calliper, the diameter and height of the biscuits were measured. It
was done at 10 biscuits for each composition. For measuring the spreading factor, the
ratio of diameter to height was calculated.
7.3.18.3 Determination of the texture of the extrudates, biscuits and
noodles
The texture of the snack basis products, biscuits and noodles were measured by using
the Texture Analyser TA-XT2i® (Stable Micro SystemsTM Co., GB), by means of a load
cell of 5 kg. As a measure for the breaking force of the snack basis products, the
maximum positive force (Fmax in N) in the measuring curve, that occurred when the
single extrudate balls were compressed and broken at constant speed with a test plate
(compressing disk made of aluminium, d = 100 mm, HDP/90), was determined . Before
measuring, the extrudates were conditioned at 20 °C and 50% RH. Settings of the
Texture Analyser: Test method: force in direction of compression, breaking test; test
speed: 0.1 mm/s; post test speed: 10 mm/s; distance of breakage and test distance: 3 mm and 4 mm (at 10 and 20% Sacha Inchi flour extrudates and 10% Sacha Inchi press
cake extrudate) and 2 mm and 3 mm, respectively (at 30 and 40% Sacha Inchi flour
extrudates); trigger value: 0.20 N. After the setting of the parameters, the Texture
Analyser was calibrated using a 2 kg standard weight (for each product the same). Ten
balls of each recipe were measured.