Potato starch juice extraction

While potato tuber is an important source of starch, it also contains 30-35 g buffer-extractable protein per kg dry weight (Pots et al., 1999). Protein yield per hectare of potatoes has been estimated as 500-1000 kg. The aqueous solution remaining after industrial potato starch manufacture, i.e., the potato fruit juice, contains approximately 1.5% (w/v) of soluble protein, mainly... 

The goal of this step is to separate fiber from the starch-fiber cake with an acceptable starch loss. Some small fiber particles may remain in the rough starch. For fiber removal, diluted cake from the potato juice extraction is sieved in so-called centrifugal sieves. This type of sieve consists of a conical rotating sieve with perforations of 125 pm (Figure 11.13). 

One source of ethanol is sugar-cane or the molasses remaining after the juice has been extracted. Other plants such as potatoes, corn and other grains require processing to convert the starch to sugar. This is done by enzymes. 

P-Enzyme was isolated from potato juice by Hanes in 1940 since then, preparations of various degrees of purity have been obtained from many higher plants. Potato P-enzyme has been intensively studied, and prepared in crystalline form. Extracts of the flagellate Polytomella coeca, which synthesizes a two-component starch, also contain P-enzyme. ... 

Foam fractionation is a relatively inexpensive technique for protein separation. Most studies in the literature are, however, experimental and very few report on industrial appUcations. Among other appUcations, foam liaclionation has been used to separate wheat flour proteins, ovalbumin, lysozyme, egg albumin, milk proteins (e.g., beta-casein, bovine lactoferrin, bovine serum albumin, alpha-lactalbumin, and beta-lactoglobulin) and potato protein from potato juice waste water after starch extraction (Weijenberg et al., 1978 Keller et al., 1997 Hossain and Fenton, 1998 Brown et al., 1999 Wang and Liu, 2(X)3 Wang etal., 2009). 

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