No abstract

The fruit of date palm tree Phoenix dactylifera is among the most abundant fruits, and it is rich in essential nutrients. Quality-wise, not all cultivated date fruits meet the commercial standards, and tons of date fruit that are immature, or of poor appearance but with no reduced nutritive value are treated as date by-product and are being used for animal feed or are discarded during processing by the relevant industries. Together with the rejected fruit, date seed which is the inedible part, and the trimmed fronds of the date palm, they are all discarded, resulting in an environmental problem, and an economical loss. The objective of this review is to identify current practices on the uses of low-grade date, seed, and frond in the industry. The literature shows date fruit of low quality is typically processed to make date paste and date syrup, and both are well utilized in the food sector. The chemical composition of date seed, and increasingly of other parts are well known, and fully exploited in many industrial applications.

Utilising major waste products from the food industry can have both a great environmental impact and be a means to improve consumer health. Date seed is a food industry byproduct that has been proven to have high nutritional value. The aim of this work was to measure the total polyphenolic content (TPC), flavonoids, and antioxidant activity of the seeds of six date fruit varieties, Fard, Khalas, Khinaizi, Sukkary, Shaham, and Zahidi, and to use those seeds to enhance the antioxidant value of cookies by partially substituting flour with ground date seed. Date seed powder (DSP) was extracted at three levels of sample to solvent ratio (5:1, 10:1 and 15:1 mg/mL). Cookies were prepared using three substitution levels of wheat flour (2.5, 5.0, and 7.5%, w/w) by DSP and two types of flour (white and whole wheat), and were baked at two different temperatures, 180 and 200 °C. The composite cookies were found to contain a significant amount of TPC and flavonoids, and showed increased antioxidant activity compared with the control samples.

Date seeds are a major waste product that can be utilised as a valuable and nutritional material in the food industry. The aim of the present study was to improve cookies quality in terms of functional and textural value and assess the effect of date seed powder flour substitution on the physical and chemical characteristics of cookies. Three substitution levels (2.5, 5 and 7.5%) of flour by fine date seed powder from six varieties locally named Khalas, Khinaizi, Sukkary, Shaham, Zahidi and Fardh were prepared. Two types of flour were used (white flour and whole wheat) at two different baking temperatures: 180 and 200 °C. The incorporation of date seed had no or slight effect on moisture, ash, fat and protein content of the baked cookies. On the other hand, incorporation significantly affected the lightness and hardness of cookies; the higher level of addition, the darker and crispier the resulting cookies. The sensory analysis indicated that the produced cookies were acceptable in terms of smell, taste, texture and overall acceptability. The results indicate that the most acceptable cookies across all evaluated parameters were produced using whole wheat flour with 7.5% levels of date seed powder using Khalas and Zahidi varieties. Overall, the analysis indicated that cookies with acceptable physical characteristics and an improved nutritional profile could be produced with partial replacement of the white/whole wheat flour by date seed powder.