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ipomoea_batatas_l._lam [2017/11/18 20:13]
andreas |
ipomoea_batatas_l._lam [2023/12/29 15:26] (aktuell)
andreas |
| Thermal degradation of the polar fraction produced acetol, furyl aldehyde, furfuryl alcohol, and 5-hydroxymethyl-2-furfural (HMF). The major components of the polar fraction included fructose, glucose, and sucrose and the volatiles identified were typical sugar-derived volatiles. Based on the absence of a number of the volatiles in the polar fraction found in the sweet potato sample, components within the polar fraction did | Thermal degradation of the polar fraction produced acetol, furyl aldehyde, furfuryl alcohol, and 5-hydroxymethyl-2-furfural (HMF). The major components of the polar fraction included fructose, glucose, and sucrose and the volatiles identified were typical sugar-derived volatiles. Based on the absence of a number of the volatiles in the polar fraction found in the sweet potato sample, components within the polar fraction did |
| not appear to significantly contribute to the overall volatile profile. Volatiles identified from the nonpolar fraction included acetol, furyl aldehyde, 5-methyl-2-furfural, furfuryl alcohol, and ß-ionone. Acetol, furylaldehyde, 5-methyl-2-furfural, and furfuryl alcohol appear to be synthesized from sugars (glucose, fructose, and sucrose). Based upon the presence of ß-carotene in the nonpolar fraction, volatiles derived from the thermal degradation of ß-carotene would be anticipated. Of the typical ß-carotene thermal degradation volatiles, only ß-ionone was found in detectable quantities... Maltol was found only in the insoluble fraction and thermolyzed sweet potatoes. The thermal degradation products of sugars, with or without maltose, were devoid of maltol. These results indicate that the formation of maltol is dependent upon substances other than or in addition to sugars. A previous report indicated that maltose was the efficient precursor for maltol in the presence amino acids. An amino-carbonyl reaction appears, therefore, to be critical for the synthesis of maltol and the characteristic aroma of baked sweetpotatoes. 1-Deoxyhexosone, a methyl dicarbonyl intermediate derived from amadori compounds, has been proposed to be a common precursor of maltol, which is formed upon the release of two molecules of water. Since the volatile thermolytic products from the sugar standard and maltose did not contain maltol, it would appear that the synthesis requires the presence of an appropriate nitrogen source, e.g., amino acids or proteins." \\ | not appear to significantly contribute to the overall volatile profile. Volatiles identified from the nonpolar fraction included acetol, furyl aldehyde, 5-methyl-2-furfural, furfuryl alcohol, and ß-ionone. Acetol, furylaldehyde, 5-methyl-2-furfural, and furfuryl alcohol appear to be synthesized from sugars (glucose, fructose, and sucrose). Based upon the presence of ß-carotene in the nonpolar fraction, volatiles derived from the thermal degradation of ß-carotene would be anticipated. Of the typical ß-carotene thermal degradation volatiles, only ß-ionone was found in detectable quantities... Maltol was found only in the insoluble fraction and thermolyzed sweet potatoes. The thermal degradation products of sugars, with or without maltose, were devoid of maltol. These results indicate that the formation of maltol is dependent upon substances other than or in addition to sugars. A previous report indicated that maltose was the efficient precursor for maltol in the presence amino acids. An amino-carbonyl reaction appears, therefore, to be critical for the synthesis of maltol and the characteristic aroma of baked sweetpotatoes. 1-Deoxyhexosone, a methyl dicarbonyl intermediate derived from amadori compounds, has been proposed to be a common precursor of maltol, which is formed upon the release of two molecules of water. Since the volatile thermolytic products from the sugar standard and maltose did not contain maltol, it would appear that the synthesis requires the presence of an appropriate nitrogen source, e.g., amino acids or proteins." \\ |
| [Identifying Critical Volatiles in the Flavor of BakedJewel'Sweetpotatoes [Ipomoea batatas (L.) Lam.]., Sun, J.B., Severson, R.F., Schlotzhauer, W.S., Kays, S.J., Journal of the American Society for Horticultural Science, Vol.120(3), 1995, 468-474] \\ | [Identifying Critical Volatiles in the Flavor of Baked 'Jewel' Sweetpotatoes [Ipomoea batatas (L.) Lam.]., Sun, J.B., Severson, R.F., Schlotzhauer, W.S., Kays, S.J., Journal of the American Society for Horticultural Science, Vol.120(3), 1995, 468-474] \\ |
| [[http://journal.ashspublications.org/content/120/3/468.full.pdf]] | [[https://www.academia.edu/download/47771363/468.full.pdf]] |
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| Vitamin A equivalent of orange-fleshed sweet potatoes (258-1338 RE/100g) was much more than of white-fleshed cultivars (0.1-6.6 RE/100g). \\ | Vitamin A equivalent of orange-fleshed sweet potatoes (258-1338 RE/100g) was much more than of white-fleshed cultivars (0.1-6.6 RE/100g). \\ |
