مقاله انگلیسی رایگان در مورد میوه خرما: عدم استفاده بهینه غذایی – الزویر 2017

The tree of dates or the palm date (Phoenix dactylifera L., Family Arecaceae) has played an important role as a food security crop in the Middle East and North Africa region (MENA), providing valuable food for people for the last 5000 years. In appreciation of its fruits, the date tree is referred to as the sacred tree [74], the tree of life [69], and the bread of the desert [84]. The latin name of the tree is believed to have been derived from Greek Phoenix daktulos, which means purple or red finger. Currently, about 100 million date trees are cultivated globally out of which ~90% are grown in the MENA. The annual global production of dates was recorded as 7.5 million tons in 2008. There is massive expansion in land areas being used for cultivation of dates not only in MENA region but also in other countries such as Australia. Date fruits are consumed at three different stages of maturation, the mature but unripe Khalal or Bisr (50% moisture), ripened Rutab (30–35% moisture), and mature Tamr (10–30% moisture) [18,34,88,89]. Due to the surplus production of dates, soft and semi-dry varieties are commonly stored after partial drying to a moisture level b25%, which has shown acceptable shelf life. Overproduction of dates with limited processing leads to huge losses especially for low grade fruits. Major losses, as high as 2 million tons per year, are globally observed during harvesting, storage, conditioning, and processing [21]. Low grade date fruits are dehydrated, grounded, and mixed with grain to form a very nutritious feed for camels and horses in the desert. Date seeds are added to animal feed for cattle, sheep, camels, and poultry. Date fruits have enormous scope and potential for use as food because of their nutritional and economical value [50]. Date fruits contain 6.5–11.5% total dietary fibers (of which 84–94% insoluble and 6–16% soluble dietary fiber), about 1% fat, 2% proteins, and 2% ash and is a rich source of phenolic antioxidants (1–2%) [87]. Variations in the chemical composition of date fruits is expected to influence their nutritional value, sensory quality, and industrial utilization. Date seeds, representing 10–15% of the whole fruit [13,64], is a valuable byproduct of date fruit processing industries and is characterized by a high level of water-insoluble mannan fibers and may be used to enhance the fiber content of certain food products. Date fruit is a key food security resource in the aridlands that requires intensive efforts for valorization. There is a large potential to especially develop healthy food products utilizing the high value fiber and phenolic antioxidants found in the fruit flesh and seeds. The ability to use dates to produce value-added products; such as date flour, fiber concentrate, juices, jam, date-based fruit bars, sugar, and functional ingredients in beverages, dairy and baking industry will help to make the palm date an economically viable commodity. However, steady and goal-oriented research and development is required to achieve this goal. The aim of this review is to summarize published research and patents on date fruit utilization, with special focus on the opportunity to develop knowledge on date fibers and phenolic antioxidants as ingredients in functional food products.