Delicious DatesAvailable all year round

Delicious DatesAvailable all year round

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FCA

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-04-

2012

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Table of Contents

Dates in the UAE 6

Ingredients of Dates 9

Nutritional and Medical Benefits of Dates 10

Tannins and their Role during the Stages of Date Ripening 13

Role of Enzymes in Date Ripening 13

Different Stages of Dates 14

Date Storage between originality of the past and

facilities of the Present 20

General Guidelines for drying dates 22

Modern methods of date packaging and packing 24

Signs of Date Decay 25

Food Safety Considerations and Potential Hazards 25

Controlling Hazards Related to Date Palm Tree Pollution 27

Programs of the Abu Dhabi Authority with Respect to

Date Safety safety of dates: 27

Program for Monitoring Pesticide Residues in Dates 28

Program For Detecting Metal Pollutants and Mycotoxins 28

Program for Examining the Microbiological Contamination of Dates 29

References 30

The cultivation of date palm trees has spread throughout the United Arab Emirates where the country has made tremendous growth in the cultivation of large numbers of this blessed tree and has increased its production and manufacturing of dates. The Ministry of Environment and Water also developed a website dedicated to date palm research, and has compiled documentation of the types of dates that have come to be grown in the Emirate of Abu Dhabi.

Dates in the UAE

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Dates contain many substances, which are needed by the human body, including: glucose, fructose, sucrose,

starch; and minerals such as potassium, sulfur, phosphorus, iron, sodium, magnesium, and zinc. It also

contains vitamins A, B, C, and E; in addition to fats, and acids such as phosphoric acid, folic acid, formic acid,

cellulose, pectin, tannin, proteins.

Nutritional Value of some Types of Dates according to the Results of an Analysis conducted at the

laboratories of the Abu Dhabi Food Control Authority:

The nutritional components of dates were analyzed at the laboratories of the Abu Dhabi Food Control

Authority with respect to the following types: Birhi, Khalas, Jibri, Lulu, Kheneizi, Sekkeri and the following

results were reached:

• Thedisaccharides,monosaccharidesandtotal

saccharides based on wet weight:

- Sucrose content percentage 0.8 - 2.3%

- Glucose content percentage 13.7 - 32.3% :

- Glucose content percentage 12.8 - 30.7% :

- Maltose content percentage 0.7 - 1.8%

- Reducing Sugar content percentage 27.6 - 61.6%

- Total Saccharides content percentage 30 - 61.6%

• Fiberanalysis3.2-3.4%

• Proteincontent

percentage 1 - 1.97%

• Fat content percentage

0.01- 0.4%

Ingredients of Dates

Minerals quantity expressed as one part per million

Potassium 5219 – 7672

Phosphorous 980 – 1336

Calcium 333 – 819

Magnesium 460 – 711

Zinc 2.65 – 12.36

Copper 0.652 – 2.04

Iron 5.69 – 17.79

Manganese 2.12 – 3.9

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Nutritional and Medical Benefits of Dates

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Dates have many benefits, such as:

• A general tonic which treats anemia and protects against nervous disorders because it contains a

high percentage of sugar and potassium.

• It also helps the womb to contract at delivery and in secreting the hormones that stimulate lactation for

breastfeeding women )such as the prolactin hormone(, because it contains glycine and threonine.

• Dates reduce the risk of heart disease and clogged arteries. It is among the foods that help treat and

prevent increased blood cholesterol by reducing the absorption of cholesterol in the intestinal tract

because it contains soluble pectin.

• The date skin contains a high level of flavonoids, which act as antioxidants and as stimulus and catalyst

for the heart by strengthening the walls of the blood vessels, prevent capillary permeability and bleeding

and act as anti-fungi, anti-bacterial, anti-viral, and anti-cancer agent.

• It also contains cellulose fibers, which activate the bowel movement, and helps to treat chronic

constipation.

• It is also rich in many compounds that enhance the immune system, such as

“beta glucan 1-3 D”, which activates the body's immune system and has the

ability to unite with, or enclose materials alien to the body.

• Tannins, which are in the class of "polyphenols," account for 3% of the components of the fruit of

palm trees.

• Throughout the stages of ripening, tannins become insoluble and they associate with proteins,

leading to improving the taste of dates and ridding them of their acidic taste.

• Tannins play a role in transforming the color of the fruit to brown, along with the transformation

caused by enzymatic activity.

The following enzymes play a major role in the fruit ripening process and bring about physiological

changes during the fruit ripening stages:

• The invertase enzyme converts the disaccharides “sucrose” the monosaccharide “glucose and

fructose” which affects the taste of fruits, as fructose is sweeter.

• Polygalacturonase and pectinesterase enzymes work to transform the pectin materials to soluble

pectin, which helps to soften the tissue of the fruit.

• The cellulase enzyme breaks down cellulose, which increases soluble materials and glucose and

reduces the proportion of the fibers.

• The “polyphenol oxidase” enzyme causes vital chemical changes in natural phenolic materials such as

tannins, and is an important enzyme in that it changes the dates' color to brown.

Tannins and their role during the Date Ripening Process

Role of Enzymes in the Date Ripening Process

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• The Hibabo stage.

• The Khlal )full-size( stage.

• The Bisr stage.

• The Rutab )ripe, soft( stage.

• The Tamr )ripe, sun dried( stage.

The Hibabo Phase.The Hibabo stage starts right after pollination and it lasts for

five weeks during which the fruit is small and spherical then

another stage starts, namely the kimri stage during which the

fruit becomes oval and green, but bitter.

The Al-kimri StageDuring this phase, the fruit grows rapidly in size and becomes

less bitter as the percentage of sucrose increases. This phase

witnesses the greatest increase in fruit acidity and water

content )which reaches 85%(; the fruit also assumes its final.

shape when its would-be color starts to appear.

Stages of the Date Palm Tree

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During this phase, the fruit reaches its final size and takes on the color and shape representative of its

type, which makes it easy to identify the different types. The ratio of water decreases from 85% to 50%;

the fruit becomes hard but crispy; and the taste improves as the tannin starts to sediment, causing the

fruit to lose its acidic taste and become sweet.

This process occurs rapidly in some types of dates, which makes such types edible during this phase as the

color of the front part of the fruit turns brown. Care must be taken when harvesting the fruits to prevent

damage. Some types such as the Birhi and Kheneizi can be marketed during the Bisr phase.

The Unripe or Bisr Stage

• The Rutab phase is charcterized by a decrease in weight, and the disaccharide “sucrose” is transformed

into the monosaccharides “glucose and fructose” according to the fruit type.

• The outer skin of the fruit becomes brown and the texture become soft.

• When the ratio of water is in the order of 30 to 45%, the fruits can be marketed during this phase as

fresh fruits which require caution to protect them from being damaged.

The Rutab (Ripe) Phase

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When fruits are left to ripen while in the trees, they naturally progress from the rutab stage to the the tamr phase charcterized by the brown or “amber” color, and they retain about 24%-25% of water.

After the fruits are harvested, they are dried in the sun to retain about 10%-20% of water. to increase their endurance while maintaining their attractive LOOK.

Texture ranges from soft to firm.

During this phase, dates are not exposed to microbic decay and can be stored at room temperature but should be protected against pollution by insects

The Tamr (Dry) Stage

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Date storage between the originality of the past and facilities of the present

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Dates are characterized by a long validity period of their validity and they can be stored at room temperature. In the past, traditional storage methods were used, such as:• Storage a Jassa )a plastered room(, which is a simple structure consisting of four walls and a ceiling

about two meters high, and whose walls are covered from inside with plaster and whose floor is covered with clean palm branches. Dates are stored in it until it is filled. Due to the weight and softness of the stacked dates and the high ambient temperature, sap flows through the floor through a special slot, a sap called molasses.

• Storage by drying: Sufficient quantities of dried dates that meet the sufficient for a year are stored.

The modern methods of Storage include:

Maintaining fruits at the bisr stage by controlling the activity of various enzymesthrough increasing or decreasing it to control the lifetime of the various types of fruits.Enzymes are sensitive to changes in heat. The enzyme’s activity stops completely when temperature is raised to the degree that leads to change in its chemical composition. The Invertase enzyme loses 50% of its activity at 50° and 90% of its activity at 65° for 10 minutes. On the contrary, cooling can reduce the enzyme’s activity to varying degrees. In addition, some temperatures such as 30°-40° stimulate the activity of enzymes, and moisture plays a major role in affecting the activity of the enzyme and in protecting the fruits from becoming contaminated with fungi and yeasts. Therefore, the storing dates by chilling or freezing reduces the activity of enzymes and extends the duration of the storage period. The properties of enzymes were used to hasten the ripening of date palm fruits according to the request and the type to be ripened.

Using chilling and freezing in date storage :Chilling and freezing techniques are used, the latter being one of the best storage methods for many food products, as freezing maintains the high quality of the product. Freezing is one of the easiest and cleanest methods, killing or stopping most of the microorganisms that cause decay and stopping or slowing down biological processes and oxidation significantly. However, enzymatic activity does not stop completely,

but continues causing the fruit to ripen and take on an an undesirable color.The freezer's temperature should be at its lowest one day at least before storing the rutab, and freezing should take place at the lowest temperature possible.

General guidelines for chilling Balah (Unripe):• The balah phase can be stored in the refrigerator temperature.• Chilling is an important and successful factor in extending the period of storing balah to several

weeks, taking into account the use of appropriate containers to reduce the formation of moisture )which causes decay and mold( or loss of moisture )which causes the fruit to dry out( on the part of balah, by using containers impermeable to water vapor. In this way, some types can be stored for three months.

• The storage period can also be extended to 26 weeks through emptying air from containers and using carbon dioxide.

General Guidelines for freezing Rutab (Ripe): The freezing process is relatively expensive, so rutab fruits should be of the best quality and in perfect condition while in the khlal phase, whether sweet or rutab. The rutab to be used in the freezing process. should preferably be processed immediately after harvest to get the highest quality possible. If it is not possible to do so, the fruits should be transported and stored in a cool place away from sunlight until they are frozen at the earliest possible opportunity. Before the freezing process, small and deformed fruits as well as impurities should be excluded, and fruits should be removed of dust and dirt by spraying )not soaking( them with cold water.

Specifications of the freezer: When buying the freezer, a number of factors should be taken into account including the the capacity of the freezer, which depends on the quantity of products expected to be stored, as well as the capacity of freezing to the lowest temperature possible )there are many freezers available on the local market, with varying freezing capabilities(, from -6° to -12°. However, the most common type of independent freezers reaches -18°. It is also advised to cook the dates )by immersion in hot water or steam( to reduce enzymatic activity before the freezing process.

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• The purpose of the drying process is to reduce the moisture content of the dates, which in turn de-creases the growth of microorganisms )bacteria, fungi, and yeast(, whose growth depends on the effectiveness of water activity for their growth, composition and ability to absorb water. In general, fungi grow in less water activity than bacteria, which in turn grows in water activity less than the bacteria. Therefore, fungi are the microorganisms that cause most decay in dates.

• Drying dates until they have 20% or less moisture content and storing them in suitable relative mois-ture greatly reduces the likelihood of their being contaminated with yeast and fungi, and extends the storage period to a year at 25 degrees.

• To prevent decay resulting from infestations of pests, dates should be fumigated with carbon dioxide for two days and their containers should be tightly sealed. They can also be vacuum-stored or heated to the temperature of 50-55° for 2-4 hours then then cooled to 0, or frozen at -18 degrees for two days, and stored at 5 degrees.

• At the level of commercial manufacture, and according to the Montreal Protocol, it was recommend-ed to stop using methyl bromide in fighting pests, because of its direct impact on the ozone layer, and the Alternative methods involve the use of phosphine or using physical methods, such as heat-ing and cooling, ozone gas, or irradiation.

General Guidelines for Drying Tamr

• The Decay is caused by microbiological contamination, including:- Alcoholic fermentation caused by yeast activity.

- Acidity caused by the activity of the lactobacillus bacteria.

- Blackening caused by the Aspergillus niger fungus.

• Defects caused by pests.- Remains of pests.

- Disruption of fruit tissues.

- Change in the outer surface of the fruits.

Risks are divided into three categories:

• Risks arising from hazardous microbiology activity (microbiological risk).

- Salmonella

- Escherichia coli.

• Physical hazards:

- Foreign objects in date products such as sharp metal fragments in date paste.

• Chemical hazards

- Pesticide residues.

- Mycotoxins resulting from fungal infection.

- Toxic metal pollution and environmental pollutants.

Signs of date decay

Considerations of Food Safety Considerations and Potential Hazards

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Modern methods of date packaging and packing• In the past, the processes of packaging and storing dates were done in a lot of farms in primitive ways, and

dates were often consumed by the farm owners and rarely marketed, and rarely marketed. If marketed, they did not fetch lucrative prices. Later, clear progress was achieved by the United Arab Emirates in packing and packaging dates in specialized factories using civilized methods. Many date factories were founded, leading to an improvement in the quality of fruits traded in markets and contributing to the use of storage during the storage and marketing periods.

Packaging and Packing

• The Rutab dates should be packaged in tightly sealed containers to avoid the so-called “freezer burns” which result from the loss of moisture, which causes the presence of brown or pale spots on the surface of fruits and affects the quality of the product. Therefore, it's not advisable to use cardboard )carton( containers unless they are coated with anti moisture transfer covers; and plastic )PVC( packages can be used instead, because they are tightly sealed and cheaper. Metal containers can also be used because their surfaces conduct heat quickly during freezing. Special packaging exists for freezing.

• There are many standards stipulated for packages, including: being impermeable to water vapor, moisture, or odors, having no taste or smell, being suitable for food products, being durable, resisting breakage due to freezing, being easy to use, seal, and write on, being designed to withstand tamping, and being cost-effective.

• The Abu Dhabi Food Control Authority, in cooperation with the concerned authorities in the United Arab Emirates, conduct field surveys and use their outputs in making recommendations on the development of specifications to ensure taking all the necessary precautions and controls to prevent the pollution of dates and their products by microbes and their toxins, as well in controlling monitoring the use of pesticides.

• Decisions were made to require date factories to commit to implementing the Hazard Analysis & Critical Control Point system )HACCP(

• The Abu Dhabi Food Control Authority encourages farmers to adopt good agricultural practices GAP.

• Transportation and storage requirements were developed:

• The Authority seeks to increase the knowledge of consumers through awareness programs to enable them to contribute to controlling food quality and safety including dates.

• The Abu Dhabi Food Control Authority plays an important role through monitoring factories to ensure that they implement date quality control systems.

• The Authority conducts inspections on a regular basis during which samples are taken of the stages of the different production lines periodically )every three months( from factories that market and export local dates and their products inside and outside the UAE for the purpose of ensuring their quality and to ensure that they are free from any pollutants and healthy for the consumer. The inspections also aim to monitor factories’ implementation of the food safety terms issued by the Abu Dhabi Food Control Authority during the manufacturing process and and to follow up their commitment to implement the Hazard Analysis & Critical Control Point system )HACCP(.

• The Authority examines samples of the dates traded in Abu Dhabi in its laboratories within its activity of inspection and survey campaigns and it monitors date exports.

Controlling the hazards of ofPollution to Date Palm Trees

Programs of the Abu Dhabi Authority with respect to the safety of dates:

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• There are many pests that infect different types of palms, and the many pesticides used to fight these pests, constitute pollutants in dates.

• Out of its concern for the safety of dates and their products used by the consumers, the laboratories of the Abu Dhabi Food Control Authority developed a method for detecting pesticide residues in dates through which most of the pesticides used in the palm pest control program can be detected.

• An annual surveying program has been developed for the detection of pesticide residues during the various stages of the date ripening process during which the focus will be on local products and some types imported from neighboring countries.

• Microorganisms which pollute dates can be detected during routine analyses for the detection of bacteria, yeasts and molds. Through these surveys, the Abu Dhabi Food Control Authority reduced the percentage of yeast and mold contamination of dates from 24% in 2006 to 16-19% in 2009.

• The surveys, which lasted for the period from January- August 2006, covered a number of types of dates and various date pastes, for a total of 231 samples of the following local types of dates: Lulu, Al-Naghal, Khalas with all its types, Shishi, Khidri, Rashidi, Safawi, Sifri, Saji, Sekkeri, Mabroum, Abuamaan, Barhi, Nabtat Saif, Omm El-Dehn, Maktomi, Dabbas, Arziz, Fard, Jibri, Kheneizi, Khadrawi, Nawat Al-Barkh, Berni, Nemishi, Sultana, Zamli, Sayr, Birdy and Maknouz.

The laboratories of the Abu Dhabi Food Control Authority detect mycotoxins )aflatoxins( in dates on a regular basis. During the period since March 2009, surveys have examined 162 samples of dates. These included the following types: Dabbas, Lulu, Kheneizi, Nagal, Abuamaan, Shishi, Khilas, Arziz, Fard, Sifri , Khidri, Sekkeri, Saji, Rashidi, Sayr, Nabtat Saif, Jibri, Dabbas, Sultana, Barhi, Khadrawi, Maktomi, Nemishi, Mabroum, Safawi Daqlet Nour, Zamli, and Omm El-Dehn. All of them were found to be in conformity with the UAE standard specifications and no basic heavy metal contaminants such as arsenic or lead were detected.

Program for Monitoring Pesticide Residues Residues in Dates

Program for Examining the Microbiological Contamination of Dates

Program For Detecting Metal Pollutants and Mycotoxins

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1. http://www.moew.gov.ae/Ar/InformationCenter/Pages/PalmTree.aspx

2. http://www.uae.gov.ae/uaeagricent/palmtree/typeofpalm-pic.stm#4

3. ABDULLA( H. ABBOUDI AND A.K. THOMPSON- MINISTRY OF AGRICULTUREAND FISHERIESDUBAI, UAE

4. Elhadi M. Yahia - Facultad de Qumica, Universidad Autَnoma de Querétaro Querétaro, Qro., México- http://www.ba.ars.usda.gov/hb66/059date.pdf

5. Kader, A.A. and Hussein, Awad. 2009. Harvesting and postharvest handling of dates. ICARDA, Aleppo, Syria. iv + 15 pp.

6. Hassan Abdel-Rahman Shanana: “Date Palm Trees and Date Production in the UAE-Harvesting Dates and Taking Care of them.”

7. Dr./ Khaled Bin Naser Al-Redaiman/ Head of the Department of Plant Production and Prevention, Faculty of Agriculture and Veterinary Medicine, AL-Qusaim University, KSA.

8. Dr./Abdulla Bin Mohamed Al-Hamdan/Assistant Professor of Food Processing Engineering, Department of Agricultural Engineering, Faculty of Agriculture, King Saud University.

9. Results of Surveys and Analyses conducted by the Abu Dhabi Food Control Authority

References

Telephone: +9712 495 4000Fax: +9712 443 6190PO Box 52150 Abu DhabiE-mail: enquiries@adfca.ae

Abu Dhabi

Al-Ain

Telephone: +9713 762 4666Fax: +9713 763 6338Po Box 66066 Al-AinWebsite: www.adfca.ae

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