Subject potato

Canet, 1995). It was found that, after two or three cycles, softness ceased to be much affected by subsequent cycles (Figure 7.6). The authors concluded the following (1) that pre-cooling and a high freezing rate during the phase of maximum ice crystal formation has a positive effect on potato texture and tissue structure, (2) that slow thawing has a positive effect and (3) that it is essential not to subject potatoes to more than one freeze/thaw cycle. 

Electrolyte leakage. Tissue discs, prepared from potato tubers as described above, were incubated for 16 h at 25°C between wet filter papers. After incubation, the discs were shaken in 20 ml H2O for another 60 min. One ml of this extract was diluted 30-fold with water, and subjected to conductivity measurements using a HI 8788 apparatus (Hanna Instruments). An increase in conductivity indicates a leakage of electrolytes through lesions in the cell wall caused by enzyme action. Control samples were not incubated, they were shaken in water only. 

A homogenized sample of cereals, vegetables, fruits or potatoes (10-20 g) is extracted with an organic solvent such as acetone and methanol. After filtration, the extract is concentrated to about 20 mL by rotary evaporation below 40 °C. The residue is transferred with 5% sodium chloride (NaCl) aqueous solution and partitioned twice with n-hexane. The n-hexane extracts are dried with anhydrous sodium sulfate and subjected to a Florisil column chromatographic cleanup procedure. The eluate from the Horisil column is concentrated to dryness and the residue is dissolved in an appropriate amount of acetone for analysis by GC/NPD. ... 

Tapioca and maize amylopectins have been sub-fractionated by fractional precipitation from aqueous solution with increasing amounts of methanol,64 71 and potato amylopectin by preferential precipitation on electrodialysis of the iodine complex.72 When these three amylopectins were subjected to chromatography, and eluted with a neutral buffer, all were found to consist of several sub-fractions.70... 

In a feeding study with one male subject, a calciuretic effect prevailed when an acidic, rice-enriched diet was fed compared with a potatoe diet, in studies with women, Bogert and Kilpatrick (24) showed that feeding subjects an acidic diet resulted in elevated urinary calcium, whereas an alkaline diet induced a decline in urinary calcium. 

While the existence of a female produced sex pheromone in the Colorado potato beetle Leptinotarsa decemlineata has been the subject of controversy for many years (for a discussion see [368]) a male produced pheromone has... 

His first work in the Laboratory of Biological Chemistry was on the purification and properties of potato phosphorylase, but he soon changed his subject to the study of amino-containing sugars. It was not well understood at that time whether there were impurities in the products of separation and purification of proteins. Consequently, Onodera made up his mind to devote his whole life to identifying the chemical nature of amino-containing sugars. 

This subject has been treated comprehensively in Chapter 3. Colorful potatoes have been suggested as potential sources for food colorants,and the major anthocyanin of the purple-fleshed potato Congo, petanin, shows higher color stability than simple anthocya-... 

Maga, J. A., Holm, D. G. (1992). Subjective and objective comparison of baked potato aroma as influenced by variety/clone. In G. Charalambous (Ed.), Food Science and Human Nutrition (pp. 537-541). Elsevier Science Publishers, Amsterdam. 

Pramod, S. N., Venkatesh, Y. P, Mahesh, P. A. (2007). Potato lectin activates basophils and mast cells of atopic subjects by its interaction with core chitobiose of cell-bound non-specific immunoglobulin E. Clin. Exp. Immunol., 748,391 01. 

Figure 7.5 shows examples of the time course of the potato specimen center and the air temperatures during one, two, and four Ifeeze/thaw cycles performed at a high freezing rate (2°C min ) and a low thawing rate (0.5°Cmin ). The structural rigidity of samples subjected to four freeze/thaw cycles was less than half that of samples subjected to only one cycle (Alvarez and... 

Figure 7.5 Thermal history of the product and of the air in potato specimens subjected to one, two, and fourfreeze/thaw cycles.

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