The physicochemical components and functional properties of the gum exudates from the trunk of the almond tree (Prunus dulcis) have been investigated, along with the emulsification and foaming properties. The gum exudates are composed on dry weight basis by 2.45% of proteins, 0.85% of fats and 92.36% of carbohydrates. The latter consist of arabinose, xylitol, galactose and uronic acid (46.8 : 10.9 : 35.5 : 6.0 mass ratio) with traces of rhamnose, mannose and glucose. Moreover, gum exudates are rich in minerals, such as sodium, potassium, magnesium, calcium and iron. The emulsifying capacity was studied for a 20% w/w olive oil in water emulsion as a function of gum concentration (from 3% to 12% w/w in the aqueous phase) as well as pH levels (from 3.0 to 10.0). The most stable and homogeneous emulsion was prepared with an 8% w/w aqueous almond gum solution at a pH between 5.0 and 8.0. In particular, for the same formulation, the emulsion processed by high pressure homogenization (5 passes at 200 MPa) resulted to be extremely stable under accelerated ageing, exhibiting no significant change in droplet size distribution for 14 days at 55 degrees C. All the tested systems exhibited an extremely low foaming capacity

Almond gum and gum arabic were used as edible coatings for sweet cherries in order to delay their ripening during postharvest storage at 2C and 90-95% relative humidity for 15 days. Coating of sweet cherries with 10% almond gum or gum arabic has been found to enhance their shelf life and postharvest quality. Fruits coated with almond gum or gum arabic showed a significant decrease in respiration rate as well as ethylene production. Moreover, coatings were able to delay changes in weight, firmness, titratable acidity, soluble solids concentration and color development compared with uncoated control fruit. The results suggested that by using almond gum as an edible coating, we can delay the ripening process and increase the shelf life of sweet cherries stored at 2C for 15 days without any spoilage and off-flavor. PRACTICAL APPLICATIONSEdible coatings could be an effective tool for delaying the ripening process of fruits and vegetables during the postharvest storage period. The effectiveness of almond gum from Prunus dulcis as a novel edible coating, in comparison with gum arabic, was studied in sweet cherries in order to maintain parameters related to quality during postharvest storage. The results showed that almond gum was able to slow down the gas exchange by reducing the CO2 concentration of coated sweet cherries, which reduced their ethylene production. As a result, the evolution of parameters related to the quality of sweet cherries was significantly delayed. Moreover, the results suggested that almond gum could be explored as a novel and potential natural edible coating to substitute the synthetic forms of fruit and vegetable packaging.

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Zizyphus lotus seeds are rich in fat and protein which are of potential industrial significance. In addition, Zizyphus lotus L. seed oil contained many bioactive compounds. This fact is of great economic interest owing to several applications of Zizyphus lotus L. seeds in the food, cosmetics and medicinal industries.

The use of coatings is a technique used to increase postharvest life of the fruit. Almond gum exudate was used, in comparison with gum arabic, at concentrations of 10% as a novel edible coating, to preserve the quality parameters of tomato (Solanumlycopersicum). Fruits were harvested at the mature-green stage of ripening. Results showed that the coatings delayed significantly (p < 0.05) the changes in color, weight loss, firmness, titratable acidity, ascorbic acid content, soluble solids concentration, and decay percentage compared to uncoated control fruits. Sensory evaluation proved the efficacy of 10% almond gum and gum arabic coatings to maintain the overall quality of tomato fruits during storage period (20 days). In addition, the difference between gum arabic and almond gum coatings was not significant (p > 0.05) except for pulp color. Therefore, we can suggest the use of almond gum exudate as a novel edible coating extends the shelf-life of tomato fruits on postharvest.