Carrots undergoing

Figure 3.11 illustrates the drying curves and temperature evolution patterns of a material (carrots) undergoing LPSSD. These data show clearly that the drying temperature and pressure both have significant effects on the moisture and... 

Figure 3.12 illustrates sample drying curves and temperature evolution patterns of a material (again carrots) undergoing VD at the same drying conditions as those shown in Fig. 3.11. It can be seen that the moisture and temperature evolution patterns (or heat and mass transfer behavior) of the material are quite different from those of the sample undergoing LPSSD. In the case of VD, the material temperature continuously increases toward the drying temperature without having a constant-temperature period. However, the vacuum-drying rates are seen to be higher than the LPSSD rates at the same operating conditions, as mentioned earlier.

Hiranvarachat, B.. Suvarnakuta, P Etevahas-tin, S 2008. Isomerisation kinetics and antioxidant activities of p-carotene in carrots undergoing different drying techniques and conditions. FoodChem. 107 1538-1546. 

Suvarnakuta, S., Devahastin, S Mujumdar, A. S., 2005a. Drying kinetics and P-caro-tene degradation in carrot undergoing different drying processes. J. Food Sci. 70 S520-S526. 

Plant. Undergoes demethylation and demethoxylation in plants (Hartley and Kidd, 1987). Metabolites identified in carrots 117 d after treatment were 3,4-dichlorophenylurea, 3-(3,4-di-chlorophenyl)-l-methylurea, and 3,4-dichloroaniline. About 87% of the linuron remained unreacted (Loekke, 1974). 

Exempt colors do not have to undergo formal FDA certification requirements, hut are monitored for purity. The colorants exempt from FD C certification are annatto extract, /i-carolene, beet powder, 0-apo—8 -carntenol. canlhaxanthin. caramel, carmine, carrot oil. cochineal extract, cottonseed Hour, ferrous gluconate, fruit juices, grape skin extract, paprika, paprika oleoresin. riboflavin, saffron, titanium dioxide, turmeric, turmeric oleoresin. ultramarine blue, and vegetable juices. See also Colorants (Foods). 

Fruits and vegetables undergoing processing come from different parts of a plant. They are roots (carrots, parsley, beetroots), stems (kohlrabi, potatoes), shoots (asparagus, onions), leaves (cabbages, spinach), flowers (cauliflower, broccoli), fruits (tomatoes, cucumbers, pumpkins, apples, pears, plums, green bean), and seeds (green peas, beans) and must be appropriately prepared for the osmotic process. 

Plant cells are less specialized than animal cells in their metabolic abilities. An animal cell can develop or lose some metabolic properties depending on the tissue however, this process is mostly irreversible, e.g., there is no way known at present to reverse the development of a nerve cell or a liver cell into an embryonic one. This is true to some extent for plant cells also usually a leaf cell performs leaf metabolism, while a root cell performs only root metabolism. Under certain conditions, it is possible to change the metabolic properties. It was shown by Steward (1964) that carrot root cells, when released from the limitations of their normal tissue environment, can undergo differentiation to form all possible types of cells, leading ultimately to an entire plantlet. Some leaves or pieces of stem can readily form roots. Therefore, owing to this metabolic versatility, one might expect that alkaloids can be formed in all cells of a plant. This may be the case in some plants, such as Ricinus communis (castor bean), but it is not universal. 

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