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Factors such as temperature (20, 60℃), pH (4.5, 7.0), gaseous phase (N₂, O₂), and light (0 lux, 5,000 lux), antioxidants and packaging conditions were investigated to study the effects of above factors on the chlorophyll components in spinach during storage. Regardless of other factors, as the storage temperature increased from 20℃ to 60℃ and pH decreased from 7.0 to 4.5, the contents of chlorophyll a and chlorophyll b in spinach decreased significantly (P$lt;0.05). The amounts of chlorophyll a and chlorophyll b in spinach stored in nitrogen gas were significantly (P$lt;0.05) lower than those in sample in oxygen phase. As the light intensity increased from 0 lux to 5,000 lux during storage, the contents of chlorophyll a and chlorophyll b in spinach significantly (P$lt;0.05) decreased. The antioxidants reduced the degradation of chlorophyll a in a model system during dark storage by minimization of free radical oxidation. The effectiveness of antioxidants decreased as following orders; α-tocopherol$gt;ascorbic acid$gt;β-carotene$gt;catechin$gt;quercetin$gt;rutin$gt;kaempherol$gt;caffeic acid$gt;chlorogenic acid$gt;ρ-coumaric acid$gt;ferulic acid. The degradation of chlorophyll a in a model system during light storage was minimized by antioxidants due to the reduction of singlet oxygen oxidation. The antidiscoloring potential of antioxidants decreased as following orders; β-carotene$gt;α-tocopherol$gt;ascorbic acid$gt;catechin$gt;quercetin$gt;rutin$gt;kaempherol$gt;caffeic acid$gt;chlorogenic acid$gt;ρ-coumaric acid$gt;ferulic acid. The amounts of chlorophyll a and chlorophyll b in freeze dried spinach packed with polyethylene bag were significantly (P$lt;0.05) lower than those in non-packed freeze dried spinach. The package of spinach in polyethylene bag with the combination of antioxidants could be used to minimize the degradation of chlorophyll components in spinach during storage.
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