Potatoes phenolics

Spices Rosemary (1000 ppm of extract with 0.92 mmol/g total phenols) Rosemary (200 ppm of extract with 0.92 mmol/g total phenol) Dried chicken meat for soup powder (up to 1000 ppm is acceptable sensorically) Potato flakes for mashed potatoes (up to 200 ppm is acceptable sensorically) Rosemary extract gave better protection than extracts of tea, grape skin or coffee Rosemary extract gave better protection than extracts of green tea, grape skin or coffee Nissen et al., 2000 Nissen et al., 2002... 

Alonso AM, Guillen DA, Barroso CG, Puertas B and Gracia A. 2002. Determination of antioxidant activity of wine byproducts and its correlation with polyphenolic content. J Agric Food Chem 50 5832-5836. Al-Saikhan MS, Howard LR and Miller JC Jr. 1995. Antioxidant activity and total phenolics in different genotypes of potato (Solarium tuberosum L). J Food Sci 60 341-343, 7. 

Rodriguez de Sotillo D, Hadley M, Holm ET. 1994. Phenolic in aqueous potato peel extract extraction, identification and degradation. J Food Sci 59 649-651. 

Im HW, Suh BS, Lee SU, Kozukue N, Ohnisi-Kameyama M, Levin CE and Friedman M. 2008. Analysis of phenolic compounds by high-performance liquid chromatography and liquid chromatography/mass spectrometry in potato plant flowers, leaves, stems, and tubers and in home-processed potatoes. J Agric Food Chem 56(9) 3341-3349. 

Teow CC, Truong V-D, McFeeters RF, Thompson RL, Pecota KV and Yencho GC. 2007. Antioxidant activities, phenolic and [betaj-carotene contents of sweet potato genotypes with varying flesh colours. Food Chem 103(3) 829-838. 

Mondy NI, Munshi CB. 1988. Chemical composition of the potato as affected by the herbicide, metribuzin Enzymatic discoloration, phenols and ascorbic acid content. J Food Sci 53 475-476. 

In the Andes, nearly all of the about 160 varieties of wild potatoes, and two of the eight cultivated species are toxic. Some frost-resistant species that grow above 3600 m have high levels of alkaloids, which are bitter and potentially toxic. These are hybrids between Solanum stenotonum and wild potatoes such as Solanum megistacrolohum and Solanum acaulc. Other secondary plant compounds in potatoes are saponins, phytohemagglutinin, proteinase inhibitors, sesquiterpene phytoalexins, and phenols. 

Al-Saikhan, M. S., L. R. Howard, and J. C. Miller Jr. Antioxidant activity and total phenolics in different genotypes of potato (Solarium tuberosum L.). J Etnopharmacol 1995 70(1) 69—74. Abbey, M., M. Noakes, and P. J. Nestel. Dietary supplementation with orange and carrot juice in cigarette smokers lowers oxidation products in copper-oxidized low-density lipoproteins. J Amer Diet Ass 1995 95(6) 671-675. 

In irradiated potatoes, especially in some varieties and as a function of cultivating conditions of the raw material, after-cooking darkening may occur. This discoloration is attributed to formation of ferric-phenolic complexes. This phenomenon depends on the iron content, and is related to increased polyphenol formation and reduced citric acid levels, which are influenced by agronomic and climatic factors. Various technological measures have been developed to prevent this after-cooking darkening [23]. 

El-Morsi, E. A., Abdel-Naem, G. R, Shaker, E. S., Ghazy, M. A. (2000). Influence of biofertilization on total phenolic compounds and antioxidative activity of potato tubers (Solanum tuberosum L.). Arab Univ J Agric Sci,8, 1-18. 

Reyes, L. F., Miller, J. C. J., Cisneros-Zevallos, L. (2004). Environmental conditions influence the content and yield of anthocyanins and total phenolics in purple- and red-flesh potatoes during tuber development. Amer J Potato Res, 81,187-193. 

Analysis and Biological Activities of Potato Clycoalkaloids, Calystegine Alkaloids, Phenolic Compounds, and Anthocyanins... 

This limited overview on the analysis of four classes of the following secondary potato metabolites is, except for anthocyanins, largely limited to our own studies of glycoalkaloids, calystegine alkaloids, and phenolic compounds. Because interest in these potato constituents arises from potential health benefits and occasional toxicity, we also include in this overview a brief discussion of these aspects that relate to composition and a description of experimental methods. The interested reader should consult the cited references for an entry into the extensive worldwide literature on the diverse analytical and biological aspects for these metabolites. 

Figure 6.5 shows the structures of tra 5-cinnamic acid and four cinnamic acid derivatives (phenolic compounds) reported to be present in potatoes. Because potatoes are one of our major food plants, we validated with the aid of HPLC and LC/MS the content and distribution of antioxidative phenolic compounds in parts of the potato plant, in potato tubers, in the peel and flesh of tubers, in potatoes sold commercially in Korea and the United States, and in home-processed potatoes. The following discussion, based on our own studies, is followed by a brief overview of analytical methods for potato phenolic compounds by other investigators. 

Extraction of phenolic compounds from peels and flesh of potato tubers... 

Mass-Ion Fragments of Phenolic Acids in Potato Extracts... 

Table 6.5 shows the distribution of the three phenolies in the peel and flesh ofthe Korean Superior potato variety available in four sizes large, medium, small, and very small. The data indicate that the size of the potato does not seem to influence the total phenolic content, except that the ratio of peel to flesh for the very small potatoes (7.95) is about one half the corresponding ratios of the other three potatoes. These results indicate that the distribution of phenolic compounds between peel and flesh varies widely among different potato varieties. They also suggest that... 

Table 6.4 Content (in mg/100 g fresh wt) of phenolic compounds potato varieties in the peel and flesh of Korean ...

Table 6.5 Effect of potato size on the phenolic acid content of the peel and flesh of potatoes. ...

Table 6.6 lists the phenolic acid content of 25 potato powders prepared by lyophilization of commercial potatoes with unknown history. For the dry lyophilized powders, the data show that chlorogenic acid levels (in mg/lOOg wt) ranged from 3.28 for Kenebec potatoes to 637 for... 

Table 6.6 Content of phenolic compounds of freeze-dried powders prepared from fresh potatoes sold in the United States... 

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