Peaches dehydrated

FIG. 13 Shrinkage coefficient (volume/initial volume) and redness (a /10) of peach and apricot cubes air dried at 70 °C up to 35% weight reduction without (NT) or following 60-min osmotic dehydration at 25 °C at atmospheric pressure in 60% (w/w) sucrose (SU) or sorbitol (SO) solutions, added with 1% ascorbic acid and 0.5% citric acid (Campolongo, 2002 Riva et al., 2001, 2002). 

Riva, M., Corteflino, G., Maestrelli, A., and Torreggiani, D. 2001. Structure collapse and color changes in osmo-air-dehydrated peach cubes. Food Sci. Biotechnol. 10, 598-601. 

Bruises are clearly visible in NMR images of apples, peach, Asian pear, and onion [14]. A relatively new bruise is brighter than the surrounding tissue due to a decrease in the magnetic susceptibility variations in the tissue. This decrease is a result of cell damage and subsequent diffusion of moisture into air pockets in the tissue of fruit [15]. However, the very old bruise does not show up as a brighter region, but instead appears darker because of dehydration[14]. 

Fomi, E., Torreggiani, D., Battiston, R, and Polesello, A. Research into changes of pectic substances in apricots and peaches processed by osmotic dehydration, Carbohydr. Polym., 6, 379,1986. 

Fruits for dehydration are often treated with gaseous SO2 from burning sulfur as used in the manufacture of dried apricots, peaches, bananas, raisins, and sultanas. Alternatively, apple slices are generally dipped in solutions of the additive (prepared by dissolving sodium bisulfite or SO2 in water) and may receive an extra treatment with gaseous SO2 during drying. 

T. Desrosier, T.G. Smyril, and G. Paquette, Retention of carotene in green peppers and peaches after a home dehydration process. Can. Inst. Food Sci. TechnoL, 18(2) 144 (1985). 

A. Levi, N. Ben-Shalom, D. Plat, and D.S. Reid, Effect of blanching and drying on pectin constituents and related characteristics of dehydrated peaches, J. Food Sci., 53(4) 1187 (1988). 

Most of fruits and vegetables are cut into pieces before they are contacted with hypertonic solution. Shape and size of the material pronouncedly affect the rate of the process. Osmosed fruits and vegetables have different forms that come from the technology and consumer requirements [62,63], Plums were dehydrated in whole or in halves [64] apples were cutinto 12 segments [65,66] or sliced into 3 mm slices [67] or 3-4 mm thick [15]. Peaches were cut into 6 or 8 segments and pears into 8 segments [65]. Carrots were cut into cubes of 5 or 10 mm [68,69], Potatoes were sliced 5 and 10 mm thick [70], or diced [20], Papaya was cut into cubes. 

Mrak and Mackinney (1951). Instructions for sulfur house operation are given by Phaff and Mrak (1948), for sun drying fruits by Mrak and Phaff (1949), and for dehydrating freestone peaches by Mrak and Perry (1948). 

The relation of total sulfur dioxide content and other factors to color changes during storage of apricots is discussed by Nichols and Reed (1931), Nichols ei al. (1938), Chace et al. (1930, 1933), and Sorber (1944). The role of sulfuring in dehydration of cherries and small fruits is discussed by Wiegand et al. (1945), and the effects of methods of sulfuring, dehydration, and temperature of storage on ascorbic acid content and carotene content of dehydrated peaches by Eheart and Sholes (1946), as well as others mentioned previously. 

Eheart, M. S., and Sholes, M. L. 1946. Effects of methods of sulfuring, dehydration, and temperature of storage on ascorbic acid and carotene content of dehydrated peaches. Food Research 11, 332-340. 

Dried peaches are halved, pitted, peeled, sulfured, and then dried in the sun or in dehydrators. It takes 6 to 7 lb... 

Drying (dehydrating) food, except fruit, results in only small losses. Thiamin is destroyed rapidly by sulfite, a fact which may explain the loss of thiamin in dried fruits, such as apricots and peaches, treated with sulfur. 

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