Processing dried fruit

Wheat flour typically becomes white by means of normal oxidation in air during a few weeks of storage. To speed up the process, manufacturers use benzoyl peroxide as a bleaching agent. Sulfur dioxide is a reducing bleaching agent that is used to preserve dried fruits. 

If required, dried fruit would be folded in before moulding. Note the savings from the extra water and the saving from a softer flour achieved by the Chorleywood process. 

Among oxidizers used have been sodium hypochlorite, potassium permanganate, and hydrogen peroxide. Bisulfite is commonly used in the wet milling of corn (maize) and in processing wines, fruit juices, jams, and dried fruits. 

Eat dried fruit. Buying organic when it comes to dried fruit is particularly important because the process of drying fruit essentially concentrates any pesticides that are in it. 

In order to evaluate the best temperature and time of baking process, Silva et al. (2008) used an expert panel to analyze seven descriptors, including dried fruit, nutty, baked, oak, mushroom, and brown sugar. The optimal temperature and time of baking process respecting the specificity of Madeira winemaking are considered 45 °C for 4 months. On the basis of aroma extract dilution analysis (AEDA), several Maillard byproducts, such as Sotolon, 2-furfural, 5-methyl-2-furfural, 5-ethoxy-methyl-2-furfural, methional, and phenylacetaldehyde, were identified in both Malvasia and Sercial wines under study which may explain the baked, brown sugar, and nutty odor descriptors. 

Ancient peoples are known to have had dried fruits, vegetables, and meats. The pemmican of Native Americans and the jerky consumed by present-day campers and hikers are both prepared by drying. The drying process can include smoking, which may actually add antibacterial agents. The processes of dehydration and freeze-drying, used today to produce such foods as powdered coffee and soup, are variations of drying. 

Many foods contain preservatives that prolong the shelf life and/or combat infestations by insects and microorganisms. Sulfur dioxide (S02) is probably one of the oldest preservatives. For centuries, people found that if the summer harvest of fruits is to be preserved and stored for the winter months, a drying process can accomplish the task. Raisins, dates, dried apricots, and prunes are still sun-dried in many countries. The drying process increases the sugar concentration in such dried fruits, and bacteria and most other microorganisms cannot use the dried fruit as a carbohydrate source because of the hypertonic (hyperosmotic) conditions. 

Vitamin C. The universal antioxidant, vitamin C has diverse roles in health, especially for maintaining skin and for connective tissue repair, along with eye, bone, teeth, and gum health. Except for processed or dried fruits in which the vitamin C content is reduced, all of the twenty superfruits are good to excellent sources of vitamin C, especially in their fresh form. Dried, frozen, and processed superfruits will have lower vitamin C content. 

As stated by Scott (1984), published information on mycotoxins in foods processed for human consumption is limited. Information on the extent that mycotoxins persist through processing is important for risk management by food processors and regulatory authorities. Whereas past research mainly focused on cereal processing, this chapter summarizes available literature on major categories of fruit products dried fruits, fruit juices, wine and cider as fermented fruit juices, and fruit purees and jams. 

As discussed, aflatoxins are genotoxic and carcinogenic, and for substances of this type, there is no threshold below which no harmful effect is observed. Subsequently, no tolerable daily intake has been set by the JECFA or any other international or national authority. Limits for foods are set as low as reasonably achievable. The current legislation in the European Union includes a maximum level of 2 pg/kg for aflatoxin B, and 4 pg/kg aflatoxin B1 B2, Gi, and G2 for dried fruits and products processed thereof, intended for direct human consumption or as an ingredient in foodstuffs. 

Obtained results show that different phases of fruit (water-soluble compounds and insoluble product matrix) contribute to different extent to the quality preservation of dried fruit as a function of moisture content. At moisture levels higher than 3%, plasticization of the water-soluble phase can promote crystallization or deteriorative processes. Nevertheless, no relevant changes in product texture (mechanical response) occur until the moisture level reaches 12%. This observation is in agreement with the great contribution of fhe insoluble producf mafrix phase (less water-plasticizable) fo fhe mechanical properfies. 

Steam distillation is used in the laboratory if it is important to replicate the commercial process or to release all the volatile oils from deep within seeds, dried fruits or woody materials. 

At present, over 3000 tons of riboflavin are industrially produced each year. About 70% of this material is used as feed additive in the form of free-flowing, spray-dried granules or microgranules. The remaining 30% are required for the fortification of foods like breakfast cereals, pastas, sauces, processed cheese, fruit drinks, vitamin-enriched milk products, baby formulas, and clinical infusions. 

---