3.3.2. Quality characteristics of date syrups
To determine sensorial profile of date syrup, colour, texture, and
sensory quality were studied.
3.3.2.1. Colour. The CieLab (L* a* b*) colour values were affected
significantly (P < 0.05) by the different treatments as well as date
varieties (Fig. 2). Date syrup from Kentichi possessed a significantly
lighter colour (higher L* value) than Deglet Nour and Allig whatever
the extraction method. Moreover, the date syrup from Kentichi
was more yellow-coloured than date syrup from Deglet Nour and
Allig (highest b*). The enzyme-treated date syrup from all varieties
showed lighter colour (L* values ranging from 24.16 to 44) than the
control without enzyme (L* values ranging from 0.545 to 17.2). In
fact, traditional extraction (at 100 C) revealed darker syrups
compared with the enzyme-treated date syrup (at 50 C) (Fig. 2).
This browning could be attributed to non enzymatic browning such
as caramelization and maillard reaction.
Similar results were observed by Al-Hooti et al. (2002) after
enzyme treatment and autoclaving treatment of date syrup.