Dried Fruit - Production

Production

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 of 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 of water activity.
• Fruit-sugars add sweetness, humectancy, 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 which 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 approximately 500,000 people 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.