Characteristics of Pollen Grains of Different Date Pollinator Cultivars and Their Metaxenia Effect on Secondary Metabolites, Enzymes and Other Biochemical Compounds of ‘piarom’ Dates at Different Stages of Fruit Growth

In this study, the characteristics of pollens of eight date pollinating cultivars including ‘Shahani’, ‘Zahedi’, ‘Beraem’, ‘Faryab’, ‘Sheikhali’, ‘Fard’ and ‘Jarvis’ were compared and their metaxenia effects on secondary metabolites, enzymes and other biochemical compounds of ‘Piarom’ date fruit was investigated in four stages of fruit growth and development. The pollens of these eight pollinating cultivars were compared in terms of carbohydrate, protein starch, total phenol, flavonoids, pectin methyl esterase, and amylase enzymes. According to the results, , pollens of ‘Sheikhali’, ‘Fard’, ‘Zahedi’ and ‘Shahani’ cultivars had higher amounts of the above compounds than other cultivars. Regarding the effect of pollens on the composition of ‘Piarom’ date fruit, ‘Fard’ and ‘Sheikhali’ pollens produced the lowest amount of soluable tannin, which resulted in better quality of ‘Piarom’ date fruits. Pollens of ‘Sheikhali’ and ‘Fard’ cultivars produced the highest amounts of glucose and fructose in the fruit. In relation to sucrose, ‘Jarvis’ and ‘Shikhali’ were the best. Pollens of ‘Sheikhali’ and ‘Fard’ cultivars caused the lowest amount of chlorophyll in different stages of fruit growth, indicating better decomposition of fruit chlorophyll and, as a result, better fruit quality. Pollens of ‘Sheikhali’ and ‘Fard’ cultivars produced the highest amount of secondary metabolites such as total phenol, carotenoids and anthocyanin at different stages of ‘Piarom’ date fruit development. Pollens of ‘Fard’ and ‘Sheikhali’ cultivars produced the highest levels of polygalacturonase, cellulase and invertase enzymes at different stages of ‘Piarom’ date fruit growth. Regarding cellulase enzyme, ‘Zahedi’ cultivar produced more ‘cellulase’ in fruit than ‘Sheikhali’. In general, the pollens of ‘Fard’ and ‘Sheikhali, in comparison with other cultivars, improved the quantity and quality of ‘Piarom’ date fruit, due to their metaxenia properties.

Preliminary Study for Inspecting Moisture Content, Dry Matter Content, and Firmness Parameters of Two Date Cultivars Using an NIR Hyperspectral Imaging System

The assessment and assurance of the quality attributes of dates is a key factor in increasing the competitiveness and consumer acceptance of this fruit. The increasing demand for date fruits requires a rapid and automated method for monitoring and analyzing the quality attributes of date fruits to replace the conventional methods used by inspection which limits the production and involves human errors. Moisture content (MC), dry matter content (DMC), and firmness (F) are three important quality attributes for two date cultivars (Khalas and Sukkari) that have been inspected using the hyperspectral imaging (HSI) technique based on the reflectance mode. Images of intact date fruits at the maturity stage Tamr were obtained within the wavelength range of 950–1750 nm. Monitoring and assessment of MC, DMC, and F [first maximum rupture force (MF, N)] were performed using a partial least squares regression model. Accurate prediction models were attained. The results highlight that the coefficients of determination (R2Prediction) are estimated to be 0.91 and 0.89 for MC, DMC, and F (N) with the lowest values of the standard error of prediction (SEP) equal to 0.82, 0.81 (%), and 4.12 (N), respectively, and the residual predictive deviation (RPD) values were 3.65, 3.69, and 3.42 for MC, DMC, and F (N), respectively. The results obtained from this preliminary study indicate the great potential of applying HSI for the assessment of physical, chemical, and sensory quality attributes of date fruits overall in the five maturity stages.

Microbiological and Organoleptic Quality Characteristics of Laboratory Produced Date Fruit-based Kunun-zaki

In the quest to produce an acceptable local beverage that could serve as an alternative variety to kunun-zaki for many millions of Nigerians who take the cereal-based beverage as their most preferred and affordable drink a study was undertaken to assess the microbial and sensory quality attributes of laboratory-produced Date fruit-based kunun-zaki. Different blends of dry date fruits (Phoenix dactylifera) and sorghum (Sorghum bicolor) formulated as follows; F1 (100:0), F2 (70:30), F3 (50:50), and F4 (30:70%) of date fruits/sorghum were soaked overnight in water, drained and were wet-milled with ginger and cloves using an equal volume of sterile water, F5 (0:100) was market (Control) sample. The microbial succession study included the identification of organisms at various critical stages of the production of the beverage. The results of the study showed the mean pH, and TTA (%) values for the respective formulated Kunun-dabino product were F1 (4.87 and 0.3870), F2 (4.66 and 0.4508), F3 (4.29 and 0.4600), F4 (4.04 and 0.4690), F5/Control (4.32 and 0.4589) respectively. The mean Total bacterial, coliform and fungal loads of the four experimental products were 2.58 x 104, NIL, and 3.56 x 103 CFU/ml respectively which fall within W.H.O’s recommended standards for ready-to-eat foods. Species of Bacillus, Enterobacter, Shigella, Lactobacillus, Aspergillus, Penicillium Mucur, and Candida were present at the initial production stage while Bacillus and Lactobacillus species persisted right through to the final stage of production. The results of the sensory evaluation showed that while F1 was the least liked, F3 was significantly preferred over the other samples (P < 0.05). The study has shown that ‘Kunun dabino’ produced under the laboratory conditions in this study provides a new brand of beverage that is both microbiologically safe and organoleptically more acceptable to taste panelists.

Technologies for the Development of New Value-Added Foods From Dates and Their Processing by-Products

The changes in consumer preferences and the increasingly competitive global market have demanded that food entrepreneurs engage in innovative value-added activities. The date is a delicatessen fruit known by its content of active compounds (e.g., dietary fiber and antioxidants) and its biological activity which has a vast potential in the design of new products such as bioactive ingredients, sugar substitutes, dietary supplements, functional foods, among others. In the current paper, innovative approaches to the value addition to date fruits and their processing by-products have been reviewed from recent high-quality scientific works. New processes such as ultrafiltration and hydrothermal treatments are shown as a useful alternative to obtain differentiated date-based ingredients (e.g., fiber concentrates, sap syrups, and date powders). Moreover, the use of date fruits and their byproducts as natural sources of value-added active compounds in the preparation of dairy, meat, and bakery and cereal products is also presented.