| Autor: |
Kirsten Herbach, Christine Maier, Florian Stintzing, Reinhold Carle |
| Předmět: |
|
| Zdroj: |
European Food Research & Technology; Mar2007, Vol. 224 Issue 5, p649-658, 10p |
| Abstrakt: |
Abstract??Purple pitaya (Hylocereus polyrhizus) fruits have been recently proposed as a promising source of betalains. In the present study, purple pitaya juice processing at pilot-plant scale is reported for the first time. Each processing step was examined in terms of juice colour and betacyanin retention. Lightness (L*) and hue angle (h?) values were strongly influenced by juice filtration, while chroma (C*) and betacyanin retention were most strongly altered by pasteurisation. Three systems of juice pasteurisation were evaluated. Betacyanin loss and colour alteration were minimal upon pasteurisation in an HTST system and a standard tubular heat exchanger, respectively. Additionally, storage experiments using mucilage-free purple pitaya juice were conducted. Whereas light exposure of unsupplemented samples resulted in significant pigment degradation, detrimental effects of light exposition were completely prevented by the addition of 1% ascorbic acid prior to storage. After 6 months, about 70% of the initial betacyanin content was retained in the presence of ascorbic acid, irrespective of illumination. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Full text from SpringerLink