UNIVERSITAT POLITÈCNICA DE VALÈNCIA Desarrollo ... - RiuNet

104 IV.Resultados y discusión. Capítulo I
oil and protein bodies. In the combined treatments, the big aggregates
seemed to be embedded in a continuous protein network (weak gel) which
could contribute to stabilise the emulsion.
Although the microstructure of hazelnut milks was not analysed, similar
behaviour could be expected, taking into account the similar nature of
product.
3.7 Sample colour
Lightness, hue and chrome values obtained in both milks are shown in
Table 4, together with the whiteness index and the colour difference
between untreated and treated samples (E). Almond milks appeared whiter
and with greater lightness than hazelnut milk due to the natural brownish
colour of hazelnut.
Both milks showed the same trends in the colour parameters when
treated, the changes being more intense in the whiter almond milks.
Lightness and whiteness index significantly increased (p < 0.05) due to the
homogenisation process, as the number and size of particles contribute to
the light reflection. In heated samples and in samples submitted to the
combined treatments, these parameters decreased (p < 0.05) in agreement
with the observed increase in particle size. On the other hand, hue and
chrome significantly decreased (p < 0.05) giving rise to a less saturated
reddish colour in all treated samples, regardless of the treatment applied.
This was more marked when using the highest temperature, to some extent
probably due to the occurrence of Maillard reactions.