46C-36 |
Antioxidative potential of some commonly used spice oleoresins as determined by Luminol-enhanced chemiluminescence measurements |
Z. Z. HAQUE1, P. Marnila2, and H. Korhonen2. (1) Dept. of Food Science & Technology, Mississippi State Univ., Box 9805, Mississippi State, MS 39762, (2) Food Research, MTT AgriFood Research Finland, Jokioinen, FIN-31600, Finland Oxidative processes during food processing and/or storage may produce free radicals that cause cellular damage. Dietary antioxidants, which scavenge active radicals into inactive ones, are thus essential for health and longevity. Spices are commonly used in food preparation and concentrates in the form of oil (oleoresins) and aqueous extracts are being increasingly used by the industry. The objective was to determine the total radical-trapping potential (TRAP) of some commonly used spice and oleoresins. Ginger, paprika, cumin, capsicum, coriander, and garlic oil (soybean oil) and aqueous extracts were obtained Kalsec, Kalamazoo, MI 49005. The TRAP were determined using a modification of the method of Wayner et al.1 which is based on measurement of induction time during oxidation of samples exposed to a free radical source with constant and known rate of free radical production under aerobic conditions. Intensity of luminol induced chemiluminescence caused by radicals from pyrolisis of 2,2’–azo-bis(2-amidinopropane)(ABAP) was monitored using a luminometer. Induction time was the time (sec) at maximum luminescence (T-Maxlu)(rlu) that occurred when protective effect of the sample was exhausted. Trolox was used as the reference antioxidant. The TRAP of the extracts varied and was highest for oil extracts (oleoresins). The T-Maxlu for oleoresin of capsicum was 2580 (sec) at a concentration of 0.006125% (v/v) compared to 420 for control (water blank) and 1200 for Trolox (2 nmol). Aqueous extract of ginger showed a T-Maxlu of 1650 (sec) at a concentration of 0.00125% whereas capsicum gave a value of 2160 at the same concentration. Cumin was less effective compared to the other spices and appeared to be pro-oxidative at low concentrations (<0.05%) as reflected by a low T-Maxlu and high maximum relative luminescence. The data indicate that valuable antioxidative protection may be provided by spices that are natural and well accepted by the average consumer.
Session 46C, Food Chemistry: Lipids, antioxidants and emulsifiers
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