Enzymatic browning in vegetal organs such as fruits and vegetables can produce undesirable color changes and unfavorably affect the taste, flavor, texture, and also the nutritional value. Dates’ color is known to play a crucial role in determining the quality and value of the fruit. The color changes from the natural accepted golden color to unfavorable dark brown color during storage period.We investigated in this study, the natural anti-browning effects of the extracts, of different parts of Phoenix dactylifera L., on polyphenol oxidase and peroxidase enzymatic activity of the fruits of date palm, Deglet Nour variety, which are widely consumable by Algerian population due to its respective health benefits.The total phenolic and flavonoid content of hydro-methanolic extracts from pedicel, perianth and leaves of date palm were also evaluated. The results showed the leaves extract is a promising source of phenolic compound with value about 27.72±0,0005 mg of gallic acid equivalents (GAE) per g of dry weight (DW). Furthermore, higher flavonoids content 12.52±0.0355 mg rutin equivalent (RE) per g DW.The anti-browning activity analyzed using a UV-visible spectrophotometer indicated that all extracts showed no effect inhibition on enzymatic activities of polyphenol oxidase (PPO) and peroxidase (POD) from fruits of date palm. This study shows that different parts of date palm, Deglet Nour variety, cannot be used as effective, natural, non-toxic anti-browning agents.

Enzymatic browning, Deglet Nour, anti-browning agents, phenolic compound, polyphenol oxidase and peroxidase

environmental engineering

Presentation: poster