Potato products influencing

The influence of the oil type and quality on oil absorption and residues absorbed by fried foods is widely documented (e.g., Blumenthal, 1991 Blumenthal and Stier, 1991 Krokida et al., 2000 Nonaka et al, 1977 Pokomy, 1980). No relationship has been found between oil type and oil absorption however, it has been shown that an increase in the initial interfacial tension between oil and restructured potato products decreases oil absorption (Pinthus and Saguy, 1994). Further, as mentioned earlier, oil degradation produces surfactants that act as wetting agents, which also increase the absorption (Blumenthal, 1991). 

Tekalign, T., Hammes, P. S. (2005). Growth and productivity of potato as influenced by cultivar and reproductive growth. II. Growth analysis, tuber yield and quality. Sci. Hort., 105,29 4. 

In frozen vegetables, health quality, nutritional quality, and aspects of sensory quality like color and texture can be objectively assessed and controlled also, in frozen potato products the effects of the thermal treatments included in the process have to be assessed due to their influence on texture, color, and nutritional value. However, in the case of overall assessment of sensory quality, only the consumer can perceive and process the overall blend of sensations that denote quality and cause consumers to prefer, accept, or reject a product. 

The product factors briefly mentioned in the previous section constitute an important field of research given the considerable influence they have on the final quality of potato products, a... 

Potato taste is not characterized by one of the primary taste sensations. Especially sweet, sour or bitter notes are considered off-flavors. However, free amino acids and 5 -nucleotides are important compounds that convey an agreeable basic taste to potato products. The amino acids occur naturally in free form the 5 -nucleotides are liberated during the heat preparation of potatoes by a specific enzymatic degradation of RNA. Starch forms a matrix for all potato preparations. Although it is tasteless, is has an influence on taste quality due to textural characteristics, and due to its pronounced capability to form stable complexes with flavor compounds either in a thermal gradient or under isothermal conditions. 

Drying methods and conditions, sample size, and shape have been shown to influence various physical characteristics including structure, density, porosity, shrinkage, and rehydration of dried potato products. These are important properties characterizing the texture and the quality of the dried potato product. 

If amylases are to be used as tools for the detailed study of the breakdown and structure of their substrates it is obviously important to separate them from other enzymes and from other naturally associated constituents which may influence the results. It is then equally important to study the properties of the purified amylase and to supply it with the chemical environment necessary to protect it from inactivation and to enable it to act efficiently. With beta amylases this ideal has often been approached. Beta amylases from several sources have been prepared by selective inactivation of other enzymes that accompany them in nature23 and highly active products have been obtained by extensive purification.20 24-26 Balls and his associates have recently reported the crystallization of beta amylase from sweet potato.27... 

Influence of Dialysis During the Hydrolysis upon the Products Formed from Lintner s Soluble Potato Starch by Purified Pancreatic Amylase (Data of Alfin and Caldwell 1)... 

The alpha amylase of malted barley causes a rapid decrease in the viscosity of its substrates and the rapid disappearance from its reaction mixtures of products which give color with iodine. Myrback80 reports a drop of 50% in the relative viscosity of potato starch when only approximately 0.1% of the glucose linkages of the substrate had been ruptured under the influence of this amylase. The achroic point for reactions of malted barley alpha amylase usually is stated to occur at approximately 30% theoretical maltose.13 In contrast, the achroic point is reached with pancreatic amylase at 40% and with the amylase of Aspergillus oryzae at 25%.41,73... 

Figure 3.9 Influence of product thickness and heat transfer coefficient on mean freezing rate for potato slices. From Rios, G.M., Marin, M. and Gibert, H., New developments of fluidization in the IQF food area, in McKenna, B.M., (ed.). Engineering and food, volume 2, processing applications, International Congress on Engineering and Food, 1983, Elsevier, 1984, figure 3. With kind permission of Springer Science and Business Media.

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