Dried fruit and nuts on a platter
|Use||Preservation of fruit for sweeteners or snacks|
Earliest: Dates and raisins|
Biggest modern: Raisins
|Nutrition||Dried fruit have most of the nutrition value of fresh fruit|
Dried fruit is fruit from which the majority of the original water content has been removed either naturally, through sun drying, or through the use of specialized dryers or dehydrators. Dried fruit has a long tradition of use dating back to the fourth millennium BC in Mesopotamia, and is prized because of its sweet taste, nutritive value, and long shelf life.
Today, dried fruit consumption is widespread. Nearly half of the dried fruits sold are raisins, followed by dates, prunes, figs, apricots, peaches, apples and pears. These are referred to as "conventional" or "traditional" dried fruits: fruits that have been dried in the sun or in heated wind tunnel dryers. Many fruits such as cranberries, blueberries, cherries, strawberries and mango are infused with a sweetener (e.g. sucrose syrup) prior to drying. Some products sold as dried fruit, like papaya, kiwi fruit and pineapple are most often candied fruit.
Dried fruits retain most of the nutritional value of fresh fruits. The specific nutrient content of the different dried fruits reflects their fresh counterpart and the processing method.
Traditional dried fruit such as raisins, figs, dates, apricots and apples have been a staple of Mediterranean diets for millennia. This is due partly to their early cultivation in the Middle Eastern region known as the Fertile Crescent, made up by parts of modern Iran, Iraq, Syria and Lebanon, southwest Turkey and northern Egypt. Drying or dehydration also happened to be the earliest form of food preservation: grapes, dates and figs that fell from the tree or vine would dry in the hot sun. Early hunter-gatherers observed that these fallen fruit took on an edible form, and valued them for their stability as well as their concentrated sweetness.
The earliest recorded mention of dried fruits can be found in Mesopotamian tablets dating to about 1700 BC, which contain what are probably the oldest known written recipes. These clay slabs, written in Akkadian, the daily language of Babylonia, were inscribed in cuneiform and tell of diets based on grains (barley, millet, wheat), vegetables and fruits such as dates, figs, apples, pomegranates, and grapes. These early civilizations used dates, date juice evaporated into syrup and raisins as sweeteners. They included dried fruits in their breads for which they had more than 300 recipes, from simple barley bread for the workers to very elaborate, spiced cakes with honey for the palaces and temples. Because cuneiform was very complex and only scribes who had studied for years could read it, it is unlikely that the tablets were meant for everyday cooks or chefs. Instead they were written to document the culinary art of the times. Many recipes are quite elaborate and have rare ingredients so we may assume that they represent "Mediterranean haute cuisine".
The date palm was one of the first cultivated trees. It was domesticated in Mesopotamia more than 5,000 years ago. It grew abundantly in the Fertile Crescent and it was so productive (an average date palm produces 50 kg (100 lbs) of fruit a year for 60 years or more) that dates were the cheapest of staple foods. Because they were so valuable they were well recorded in Assyrian and Babylonian monuments and temples. The villagers in Mesopotamia dried them and ate them as sweets. Whether fresh, soft-dried or hard-dried, they helped to give character to meat dishes and grain pies. They were valued by travelers for their energy and were recommended as stimulants against fatigue.
Figs were also prized in early Mesopotamia, Israel and Egypt where their daily use was probably greater than or equal to that of dates. As well as appearing in wall paintings, many specimens have been found in Egyptian tombs as funerary offerings. In Greece and Crete, figs grew very readily and they were the staple of poor and rich alike, particularly in their dried form.
Grape cultivation first began in Armenia and the eastern regions of the Mediterranean in the 4th century BC. Here, raisins were manufactured by burying grapes in the desert sun. Very quickly, viticulture and raisin production spread across northern Africa including Morocco and Tunisia. The Phoenicians and the Egyptians popularized the production of raisins, probably due to the perfect environment for sun drying. They put them in jars for storage and allotted them to the different temples by the thousands. They also included them in their breads and their various pastries, some made with honey, some with milk and eggs.
From the Middle East, these fruits spread through Greece to Italy where they became a major part of the diet. Ancient Romans ate raisins in spectacular quantities and all levels of society, including them as a key part of their common meals, along with olives and fruits. Raisined breads were common for breakfast and were consumed with their grains, beans and cultured milks. Raisins were so valued that they transcended the food realm and became rewards for successful athletes as well as premium barter currency.
Having dried fruits was a must in ancient Rome as these instructions for housekeepers around 100 BC tell: "She must keep a supply of cooked food on hand for you and the servants. She must keep many hens and have plenty of eggs. She must have a large store of dried pears, sorbs, figs, raisins, sorbs in must, preserved pears and grapes and quinces. She must also keep preserved grapes in grape-pulp and in pots buried in the ground, as well as fresh Praenestine nuts kept in the same way, and Scantian quinces in jars, and other fruits that are usually preserved, as well as wild fruits. All these she must store away diligently every year."
Figs again were extremely popular in Rome. Dried figs were equated with bread and formed a major part of the winter food of country people. They were rubbed with spices such as cumin, anise and fennel seeds, or toasted sesame, wrapped in fig leaves and stored in jars.
Plums, apricots and peaches had their origins in Asia. They were domesticated in China in the 3rd millennium BC and spread to the Fertile Crescent where they were also very popular, fresh and dried alike. They arrived in Greece and Italy much later and were very expensive but valued in the preparation of gourmet dishes with port or stewed with honey and spices.
|Pears (Williams or Bartlett)||400|
Today, dried fruit is produced in most regions of the world, and consumption occurs in all cultures and demographic segments. In the United States, Americans consumed an average of 2.18 lb (1 kg) (processed weight) of dried fruit in 2006. Raisins accounted for about two thirds of this. California produces the largest percentage of the US and the world's dried fruit crop. It accounts for over 99% of the US crop of raisins and dried plums, 98% of dried figs, 96% of dried peaches, 92% of apricots and over 90% of dates. Most of California dried fruit production is centered in the San Joaquin Valley where the soil and climate, especially the hot, dry summers, provide ideal growing conditions. While these fruits were commonly dried in the sun in the past, now only raisins are almost entirely naturally sun-dried.
Fruits can be dried whole (e.g., grapes, berries, apricot, plum), in halves, or as slices, (e.g., mango, papaya, kiwi). Alternatively they can be chopped after drying (e.g., dates), made into pastes, or concentrated juices. The residual moisture content can vary from small (3 – 8%) to substantial (16 – 18%), depending on the type of fruit. Fruits can also be dried in puree form, as leather, or as a powder, by spray or drum drying. They can be freeze dried. Fresh fruit is frozen and placed in a drying chamber under vacuum. Heat is applied and water evaporates from the fruit while still frozen". The fruit becomes very light and crispy and retains much of its original flavor. Dried fruit is widely used by the confectionery, baking, and sweets industries. Food manufacturing plants use dried fruits in various sauces, soups, marinades, garnishes, puddings, and food for infants and children.
As ingredients in prepared food, dried fruit juices, purées, and pastes impart sensory and functional characteristics to recipes:
- The high fiber content provides water-absorbing and water-binding capabilities, tenderization, and nutritional enhancement.
- Organic acids such as sorbitol act as humectants, provide dough and batter stability, and control water activity.
- Fruit sugars add sweetness, humectancy, and surface browning, and control water activity.
- Fruit acids, such as malic acid and tartaric acid, contribute to flavor enhancement and act as anti-microbial agents (suppress mold and bacterial growth).
- Vitamins and minerals increase nutritional value and label appeal.
- Phenolic compounds slow down lipid oxidation in meats. They add a natural caramel color.
The high drying and processing temperatures, the intrinsic low pH of the fruit, the low water activity (moisture content) and the presence of natural antimicrobial compounds in dried fruit make them a remarkably stable food. There is no known incident of a food-borne illness related to dried fruit.
Sulfur dioxide is used as an antioxidant in some dried fruits to protect their color and flavor. For example, in golden raisins, dried peaches, apples, and apricots, sulfur dioxide is used to keep them from losing their light color by blocking browning reactions that darken fruit and alter their flavor. Over the years, sulfur dioxide and sulfites have been used by many populations for a variety of purposes. Sulfur dioxide was first employed as a food additive in 1664, and was later approved for such use in the United States as far back as the 1800s.
Sulfur dioxide, while harmless to healthy individuals, can induce asthma when inhaled or ingested by sensitive people. The Food and Drug Administration (FDA) estimates that one out of a hundred people is sulfite-sensitive (allergic), and about 5% of asthmatics are also at risk of suffering an adverse reaction. Given that about 10% of the population suffers from asthma, this figure translates to 0.5% of the whole population with potential for sulfite-sensitivity. These individuals make up the subgroup of greatest concern and are largely aware of the need to avoid sulfite-containing foods. Consequently, the FDA requires food manufactures and processors to disclose the presence of sulfiting agents in concentrations of at least 10 parts per million.
In Taipei, Taiwan, a 2010 city health survey found one-third of tested dried fruit products failed health standard tests, most having excessive amounts of sodium cyclamate, some at levels 20 times higher than the legal limit.
Traditional dried fruit have a low to moderate Glycemic Index (GI) – a measure of how a food affects blood sugar levels. GI measures an individual's response to eating a carbohydrate-containing food (usually 50 grams of available carbohydrates) compared to the individual's response to the same amount of carbohydrates from either white bread or glucose. Carbohydrate containing foods are classified as high (above 70), moderate (56–69), or low (0–55) GI. Foods with high fiber content generally have a low GI. However, other factors also contribute to a food's glycemic response, such as the type of carbohydrate or sugar present, the physical characteristic of the food matrix and the presence of organic acids. All studies assessing the GI of dried fruit show that they are low to moderate GI foods and that the insulin response is proportional to their GI. Factors thought to contribute to this glycemic response include the viscous texture of dried fruits when chewed; their whole food matrix; the presence of phenolic compounds and organic acids and the type of sugar present (about 50% fructose in most traditional dried fruit).
Types of Dried Fruits
Dried mango is a dried tropical fruit. It is rich in vitamins, dietary fiber, and antioxidants
Before the drying process begins, the mango that has been sliced will usually has moisture on the surface. In the drying process, warm air that has little moisture will be used to pick up the moisture on the surface of the sliced mango. As the water on the surface is being evaporated, the water from inside the mango is also being drawn out to the surface to replace the lost moisture. The process of water being drawn out from the center of the material to the surface is called diffusion. Then the moisture will also be taken away by the warm air. As moisture is being drawn out to the surface, moisture on the surface will be less visible until it reached a point where the surface will no longer look wet. The rate of moisture removal will also be slower as time goes on. As moisture is being drained out of the mango, its cellular structure will begin to break down, causing the mango to shrink. At high temperature, moisture can be drawn out too quick that a thick hard layer is formed in the surface of the mango. The thick layer will trap moisture inside the mango making it really difficult to entirely dehydrate the mango. This phenomenon of developing hard skin-like outer layer is called case-hardening.
There are several processes applicable in the production of dried mangoes which affects its appearance, rehydration properties, and nutrients. The list consists of sun drying, tray (air) drying, freeze drying, and vacuum microwave drying. Each process has their own benefits and disadvantages.
This process beats the other methods in terms of cost due its inexpensive nature; using sun as its thermal source. However, there are many disadvantages associated such as the longer time required to dry, hot climate and daylight, and risk of invasion by animals and unwanted microorganisms.
Despite its poor re-hydration properties and shrunken appearance, this process requires a short period of time along with controlled humidity and heated air
Unlike the other drying methods, this method allows the dried mango to retain its shape, retain the highest color value, and provide a great rehydration property despite its high costs
Vacuum microwave drying
This method provides better flavor retention, great rehydration, least nutrient loss and least color change among other thermal drying along with a faster drying rate compared to freeze drying
During the drying process of mango, there are some nutritional values which are still retained and lost. 100 gram of dried mango contains about 314 calories, in which carbohydrates are the main source of calories, followed by protein and fat. Dried mango has 20% daily-value of Vitamin A and notable content of Vitamin B, D, and E. However, most of the vitamin C in the mango is lost during the process of dehydration; it carries only 2% of daily value. Minerals such as calcium, iron, and phosphorus can be found in dried mango.
With additional process of blanching, dried mango can retain the content of its carotenoids and vitamin C.
While mango’s can be stored for around 5 days, dried mango's can be stored for a lot longer depending on a variety of factors, such as the best by date, the drying method, and how the dried mango is stored. Unopened dried mango stored in the pantry can be stored between 6-12 months. If stored in the refrigerator, it can be stored for 1-2 years. When frozen, it can be stored indefinitely. However it is best to check for signs to see whether the fruit has gone bad.
The shelf life of dried mango can be extended by keeping it in a pantry or the refrigerator in a tightly sealed container to keep out moisture and other contaminants.
How to tell if the dried mango is bad, rotten, or spoiled?
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|Wikimedia Commons has media related to Dried fruit.|
- The Calorie Diary of Fresh cherries http://www.caloriesweb.com/fruit/the-calorie-diary-of-cherries/
- Drying and Storing Dried Fruit https://web.archive.org/web/20140728021929/http://www.healthyfruitleather.com/fruit-leather-faq/
- Drying Apples http://www.simplysetup.com/simple-living-2/drying-apples.html
- California Dates Administrative Committee http://www.datesaregreat.com
- California Fig Advisory Board http://www.californiafigs.com
- California Dried Plum Board http://www.californiadriedplums.org
- California Raisin Marketing Board http://www.calraisins.org
- Nut and Dried Fruit Council Foundation http://www.nutfruit.org
- How to Dry Fruit Leathers National Center for Home Food Preservation