Potato pulp components

Table 16.1 Components of conventional wet potato pulp (Mayer, 1998)...

The particulate fraction, called potato pulp, besides the fruit liquid and water in intact cells, contains starch, cellulose, hemicelluloses, pectin, and proteins. On a dry matter basis, the pulp contains 74% of protein in comparison to the content in potato tuber (Kempf, 1980). Components of conventional wet potato pulp are listed in Table 16.1. 

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). 

Vanilla can also be extracted from plants other than Vanilla planifolia, such as potato peels and pine tree sap. The most economical source of the product, however, is waste material left over from the wood pulp industry. That waste material consists primarily of lignin, a complex natural polymer that, along with cellulose, is the primary component of wood. The wastes from wood pulping can be treated to break down and separate the lignin. This leaves behind a complex... 

Potatoes 2-Isopropyl-3-methoxypyrazine together with 2,5-dimethylpyrazine (see pyrazines) dominate in raw potatoes. Key compounds in boiled potatoes are meAional and 2-ethyl-3,6-dimethylpyrazine. Tomatoes The highest flavor values in fresh tomatoes are exhibited by (Z)-3- and ( )-2-hexenals (see alkenals), j3- ionone, hexanal (see alkanals), 8-damascenone, I-penten-3-one (CsHgO, Mr 84.12, CAS [1629-58-9], 3-methylbutanal (see alkanals), and 2-isobutylthiazole. The most important flavor components in tomato pulp are dimethyl sulfide, )8-damascenone, )5-ionone, 3-methylbutanal, I-nitro-2-phenylethane (CgH,N02, Mr 151.16, CAS [24330-46-91), eugenol, methional, and 3-methylbutanoic acid. ... 

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