Abstract
A system for the extraction, filtration, and concentration of date fruit syrup was developed. The syrup was first extracted under 1000 mbar and under partial vacuums of −1.8, −2.8, and −5.5 mbar in an extractor developed by the authors, then filtered using a filtration ladder of 1.0, 0.25, 0.112, and 0.011-mm pore sizes and finally concentrated to the product known as a dip in the Arab world. The concentration of the syrup to dip was done in a rotary evaporator at 50 °C and 180 rpm for 9–11 hours and under direct sun rays at approximately 48 °C, placed in stainless steel trays (61 × 46 × 5 cm) for 4 hours (12:30–4:30 p.m. The quality of dip produced under sun evaporation was compared to that of a commercial one collected from the markets in Saudi Arabia and was found to be superior due to two decisive criteria, namely color (the appearance) and pH (the taste), and also in terms of other nutritional components.