During drying, a picture of slice 1 was taken every five
minutes. Weight was gauged every minute and product
temperature and all other measured variables were metered
continuously and electronically logged.
For the determination of the correlation between data
gained using a colorimeter (Konica Minolta CR-410) and
the camera, respectively, five samples were dried in an electric
oven (Heraeus UT 12) at 70C for 135 minutes. Before
drying, the samples were weighed and their initial color
measured. Samples were taken out of the oven in intervals
of 15 min and their color and weight were measured. Four
areas per sample were defined for the measurement with
the colorimeter. For the comparison with the values gained
from the digital pictures (whole surface of the sample), the
mean of the four values was used. Dry matter’s determination
was carried out as described above.