Potato products textural properties

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. 

Food foams are dispersions of gas bubbles in a continuous liquid or semisolid phase. Foaming is responsible for the desirable rheological properties of many foods, e.g., the texture of bread, cakes, whipped cream, ice cream, and beer froth. Thus foam stability may be an important food quality criterion. However, foams are often a nuisance for the food processor, e.g., in the production of potato starch or sugar and in the generation of yeast. Residues of antifoaming aids in molasses may drastically reduce the yield in citric acid fermentation. 

Basic principles in physio-chemical changes occurring during dehydration provided an effective approach to improve quality of dehydrated products. Carrot and potato dices infused with biopolymers before dehydration and processed under optimal conditions had good texture, high rehydration properties, good color and puffed appearance. Infused biopolymers were deposited on cell walls and intracellular spaces and may contribute to prevent cell collapse. 

In the food industry, modified starch is applied to impart appropriate texture, appearance, moisture, consistency, and stability during storage to food products. Potato starch is distinguishing itself with its physicochemical properties among other starch raw materials, and from the technological perspective, it is the best initial material for the production of modified starch preparations. 

Potato chips are fried to a final moisture level of 3% or less, which accounts to an of about 0.2. Tortilla chips, corn chips, and other snacks have a final moisture content of <3%. From a study on potato chips a moisture content of 3.57% was the point at which a taste panel rejected the chips because of their texture deterioration [39]. Moisture absorption and the consequent deteriorative changes can be prevented by the use of packaging materials with appropriate moisture barrier properties. In this case the shelf life of the products can be extended to several months. If the packaging material is not transmitted by light and if the air inside the packaging is replaced by an inert gas, e.g., nitrogen, a considerably longer shelf life can be obtained. 

Carbohydrate-based replacements rely on a viscosity increase and smooth gel-like textures to simulate the properties of fats and oils. These substitutes include gums, hydrophilic hydrocolloids that increase product viscosity and improve emulsion stability polydextrose, a polymer of dextrose with small amounts of sorbitol and citric acid made by Pfizer Chemical Division, New York and a variety of com, tapioca and potato starch maltodextrins made by various starch processors. Neither the protein- nor the carbohydrate-based replacements can be used as frying or dry coating oils. 

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