Water in potatoes

Hydrocolloidal water is an integral part of the dispersed phase and travels at the same velocity with it this is considered tightly bound water. Yakubu et al. (1990) identified three other forms of water in potato and com starch, viz., weakly bound, surface trapped, and bulk water. All forms were not present in potato starch containing less than 35% moisture, but were present in corn starch. Water, far removed from the solute surface (unbound or free water in the outer volume), travels at a different rate from hydrocolloidal water (Lechert et al., 1981). 

Directions (a) Cut a piece of potato with a knife and examine the blade. Repeat the experiment using some dry wood instead of the potato. (1) What is the evidence as to the presence of water in potato (2) In the wood ... 

Fish, B.P., Diffusion and thermodynamics of water in potato starch gels, in Fundamental Aspects of Dehydration of Foodstuffs, Society for Industrial Chemistry, London, U.K., 1958, pp. 143-157. 

FIG. 19 Action potential in the stem of a potato plant in the presence of Colorado beetles on young terminal leaves of the plant. Distance between electrodes (a) 3.5 cm, (b) 12cm, (c) 22cm, and (d) 20 cm. The plants were given water every other day and kept at 20°C. The reference Ag/AgCl electrode was inserted in stem between cotyledons. The working Ag/AgCl electrode was inserted in stem (a, b, c) or in potato seed (d). (From Ref. 7.)... 

The linear relationship between H NMR transverse relaxation rate and (1 av) is shown in Figure 30 for pregelled potato starch (Hills et al., 1999). The change in slope at about 0.90 c/w corresponds to the bulk water break (i.e., the removal of bulk water) in a corresponding adsorption isotherm. Equation... 

Liu, Q., Charlet, G., Yelle, S., and Arul, J. (2002). Phase transition in potato starch-water system. I. Starch gelatinization at high moisture level. Pood Res. Inst. 35, 397-407. 

Other orchid metabolites suchs as batatasin 1, inhibited the growth of liverworts, algae and oat coleoptiles. Batatasin 1 also inhibited the CO2 dependent O2 evolution and the flow of electrons from water to methylvi-ologen in spinach chloroplasts, and it inhibited the succinate-dependent O2 uptake in potato tuber mitochondria. Other phenanthrenes such as orchinol, which has a free hydroxyl at the 7-position, inhibit indole-3-acetic acid (lAA) oxidation catalyzed by horseradish peroxidase. 

Some 65-75% of the dry matter of the potato tuber consists of starch that is readily extractable in water (Burton, 1989). In early 19th century households in potato-growing areas it was... 

Ledoigt, G., GrifFaut, B., Debiton, E., Vian, C., Mustel, A., Evray, G., Maurizis, J. -C., Madelmont, J. -C. (2006). Analysis of secreted protease inhibitors after water stress in potato tubers. Int. J. Biol. Macromol., 38, 268-27E... 

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