Potatoes texture

For mashed potato texture, profile analysis (TPA) and cone penetration tests are performed with a TA HDi Texture Analyser (Stable Micro Systems Ltd, Godaiming, UK). During the tests, the mashed potatoes are kept at 55° C by means of a temperature-controlled Peltier cabinet (XT/PC) coupled to a separate heat exchanger and PID control unit. For the cone penetration tests, a spreadability rig is used, consisting of a 45° conical perspex probe (P/45°C) that penetrates a conical sample holder containing 7 0.1 g of mashed potatoes (Alvarez et al., 2005 Canet et al., 2005b Fernandez et al, 2006). 

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. 

Andersson, A., Gekas, V, Lind, I., Oliveira, F., Ostel, R. (1994). Effect of preheating on potato texture. Crit. Rew. Food Sci Nutr, 34,229-251. 

Martens, H. J., Thybo, A. K. (2000). An Integrated Microstructural, Sensory and Instrumental Approach to Describe Potato Texture. Lebensmittel-Wissenschaft und-Technologie, 33, 471 82. 

Dynamic rheometers have been widely used to study the viscoelastic characteristics of liquid, solid, and semi-solid foods. However, to our knowledge, very few studies on the rheological characteristics of potato flesh using dynamic rheometry have been carried out. The dynamic rheological behavior of potato tubers may be helpful to have a quick idea about potato texture and... 

Martens, H.J. and Thybo, A.K. 2000. An integrated microstructural, sensory and instrumental approach to describe potato texture. Lebensm.-Wiss. iL-Technol. 33, 471-482. 

Retain the crunchy texture of biscuits, potato chips. 

French fries are made from potatoes that have been cut into thin strips (around 1 cm square in cross-section), washed briefly in cold water, partly dried to remove surface moisture and deep fired in vegetable oil at around 180°C to a light golden color. The final product comprises around 10% fat, most of which is retained on the surface. Frozen fry manufacturers ship their products raw, par-fried, or partially cooked and drizzled with oil for baking, to suit the end user. The product is frozen at —40°C and stored at —20°C. Moisture content needs to be less than 70% in par-fried fries to prevent limpness and separation of the interior and the cmst. Heterogeneity in moisture content between strips can result in variability in texture. Fr5dng is finished by immersing the frozen product in deep fat at about 200°C until the desired color and texture are achieved. 

Taylor, M. A., McDougall, G. J., Stewart, D. (2007). Potato Flavour and Texture. In D. Vreugdenhil (Ed.), Potato Biology and Biotechnology Advances and Perspectives (pp. 525-540). Elsevier, Oxford. 

The bulk of potato tubers is made up of parenchyma cells that have thin, non-lignified, primary cell walls (Reeve et al., 1971 Bush et al, 1999, 2001 Parker et al., 2001). Unless stated to the contrary, potato cell walls refers to parenchyma cell walls. These walls and their component polysaccharides are important for a number of reasons they form part of the total intake of dietary fiber, influence the texture of cooked potato tubers and form much of the waste pulp that is produced in large amounts by the potato starch industry when starch is isolated. The pulp is usually used as cattle feed, but potentially could be processed in a variety of ways to increase its value (Mayer, 1998). For example, the whole cell-wall residues could be used as afood ingredient to alter food texture and to increase its dietary-fiber content, or cell-wall polysaccharides could be extracted and used in a similar way or for various industrial applications (Turquois et al., 1999 Dufresne et al, 2000 Harris and Smith, 2006 Kaack et al., 2006). 

Jarvis, M. C., Duncan, H. J. (1992). The textural analysis of cooked potato. 1. Physical principles of the separate measurement of softness and dryness. Potato Research, 35, 83-91. 

Kaack, K., Pedersen, L., Laerke, H., Meyer, A. (2006). New potato fibre for improvement of texture and colour of wheat bread. Eur. Food Res. TechnoL, 224,199-207. 

Bretzloff, C. W, McMenamin, J. (1971). Some aspects of potato appearance and texture. III. Sampling tubers for... 

Looking back also over the historical development of quality requirements for processed foods, freezing when properly carried out is undoubtedly the most satisfactory method for the longterm preservation of vegetable produce. The low temperatures commonly prescribed for frozen foods (—18°C) can maintain initial quality and nutritional value practically unchanged, so that frozen and fresh vegetable products differ only in texture (Canet, 1989), which is however a particularly important quality attribute in potato products. 

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. 

Texture is a key component of the quality and palatability of potato products. Texture is generally quantified by measuring the resistance of a product to an applied force. A number of different rheological parameters can be used to evaluate a range of tuber characteristics such as firmness, hardness, softness, adhesiveness, fracturability, etc. There is a considerable amount... 

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