Impact of High-Pressure Carbon Dioxide Combined with Thermal Treatment on Degradation of Red Beet (Beta vulgaris L.) Pigments
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- 作者：Xuan Liu ; Yanxiang Gao ; Honggao Xu ; Qi Wang ; Bin Yang
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2008
- 出版时间：August 13, 2008
- 年：2008
- 卷：56
- 期：15
- 页码：6480-6487
- 全文大小：341K
- 年卷期：v.56,no.15(August 13, 2008)
- ISSN：1520-5118
文摘
A combined high-pressure carbon dioxide (HP-CO2) and thermal degradation reaction of betanin and isobetanin in aqueous solution was investigated and can be described by a first-order decay. At 45 °C, the degradation rate constant (k) for each pigment component significantly increased (the half-life (t1/2) decreased, p < 0.05) with elevated pressure. Furthermore, HP-CO2 treatment led to lower k values (higher t1/2 values) than thermal treatment. However, k and t1/2 values approached those of thermal treatment when the pressure was >30 MPa combined with temperatures exceeding 55 °C. Moreover, betanin was more stable than isobetanin under HP-CO2. Ea values ranged from 94.01 kJ/mol for betanin and 97.16 kJ/mol for isobetanin at atmospheric pressure to 170.83 and 142.69 kJ/mol at 50 MPa, respectively. A higher pressure and temperature as well as longer exposure time resulted in higher values of L*, b*, C*, and h°. HP-CO2 induced more degradation products from betanin and isobetanin than thermal treatment with an identical temperature and exposure time.