Pears dehydrated

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]. 

For adsorption isotherms, pear cubes (10 mm X 10 mm) were frozen at — 40°C and freeze-dried (Telstar Lioalfa-6 lyophyliser) at 10 Pa. Afterwards, samples were placed in chambers with controlled relative humidity (RH) up to equilibrium was reached. Desorption isotherms were obtained in pear slices with skin (with approximately 8 cm diameter and 10 mm thickness), partially dehydrated in a conventional dryer at 45°C for different times to ensure different final water contents in the samples. After the drying treatment, samples were kept in plastic bags under refrigeration to ensure the internal moisture equilibration and then their water activity was measured. Experiments were carried out in triplicate for each sample. 

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. 

Andreotti et al. [31] recognize a temperature of 43 C as the optimal for osmotic dehydration of cherries and pears in glucose or glucose-fructose syrup. They recommended a tan-peiature of 20 C for osmotic dehydration of apricots. Bananas were osmoticaUy dehydrated at 60°C [146] however, it was shown that optimal temperature was dependent on the concentration and pH of the osmotic solution [105]. Pineapple was dehydrated at 42 C-47°C [96] but application of vacuum and tonperature higher than 40°C resulted in loss of volatiles [112]. Osmotic dehydration of plums is done at 50°C [147,148], kiwifruit at 37°C, and peas at 50°C-70°C [124]. 

Definition Oil obtained by pressing dehydrated avocado pear Persea americana consists principally of glycerides of fatty acids Properties YIsh.-green to brownish-green oil, faint char, odor sol. in min. oil, isopropyl esters, ethanol insol. in water dens. 0.908-0.925 iodine no. 84-95 sapon. no. 177-198 ref. index 1.460-1.470... 

Sorbitol is found in the plant world in many berries and in cherries, plums, pears, apples, seaweed, and algae. It is about 60% as sweet as sucrose (table sugar) and is used in the manufacture of candies and as a sugar substitute for diabetics. D-Sorbitol is an important food additive, usually added to prevent dehydration of foods and other materials upon exposure to air because it binds water strongly. 

Doyleite is a triclinic aluminium hydroxide mineral with composition Al(OH)3. It occurs as masses of soft white tabular crystals with pearly lustre which form from the weathering of aluminium-rich rocks in tropical climates. Hence, doyleite is often found in bauxites (. v.). Doyleite is closely related to another triclinic form of A1(0H)3, nordstrandite, and the monoclinic polymorphs, gibbsite and bayerite qq.v.), with which it may be found (Chao et al., 1985) it is also related to the orthorhombic dehydrated forms of AIO(OH), boehmite and diaspore qq.v.). Synthetic alu-minimn hydroxide Al(OH)3 is commonly encountered as a substrate for lake pigments. 

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