Kidmose Ulla, Edelenbos Merete, Christensen Lars P, Hegelund Erling
Danish Institute of Agricultural Sciences, Department of Food Science, Kirstinebjergvej 10, DK-5792 Aarslev, Denmark.
J Chromatogr Sci. 2005 Oct;43(9):466-72. doi: 10.1093/chromsci/43.9.466.
The content of individual chlorophyll and carotenoid pigments is determined in three spinach varieties (Lorelei, Springfield, and Ballet) after processing. Raw spinach and spinach that is steam-blanched for 3, 9, or 15 min is stored frozen at -24 degrees C for 6 months. In addition, spinach is air-dried at 75 degrees C, packed in atmospheric air or nitrogen, and stored at ambient temperature for 6 months. Processing has a significant effect on the content of individual chlorophyll and carotenoid pigments; however, there are no differences between varieties in their content of total and individual pigments in raw, frozen spinach. Increasing blanching time resulted in decreased contents of chlorophyll a and b and increased contents of chlorophyll a' and b' and pheophytin a and b because of pheophytinization. Changes in the color because of pheophytinization are only detected after 15 min blanching. The carotenoid pigments are more stable than the chlorophyll pigments during blanching. (all-E)-Violaxanthin is significantly reduced, caused by degradation to other xanthophylls, such as neochrome, during blanching. There are no significant differences in the content of chlorophyll a and b of dried spinach and blanched, frozen spinach. Formation of chlorophyll a' and b', pheophytin a and b, and chlorophyll a-1 and b-1 is observed after drying. The content of pheophytin a and b is significantly lower in dried versus blanched frozen samples. In dried spinach that is stored in atmospheric air, the content of beta-carotene [599 mg/kg dry matter (DM)] is significantly lower compared with nitrogen (766 mg/kg DM), and the content of (all-E)-lutein is lower than in blanched frozen spinach. Neochrome is not detected in raw spinach but in steam-blanched and dried spinach. No differences are observed in the content of (all-E)-neoxanthin, (9'Z)-neoxanthin, (all-E)-violaxanthin, (all-E)-lutein epoxide, or neolutein A and B between spinach that is stored frozen after 3 min blanching and dried spinach.
对三个菠菜品种（洛雷莱、斯普林菲尔德和芭蕾）加工后的叶绿素和类胡萝卜素色素的含量进行了测定。将新鲜菠菜及分别经过3分钟、9分钟或15分钟蒸汽热烫的菠菜在-24℃下冷冻保存6个月。此外，菠菜在75℃下风干，包装在空气或氮气中，并在室温下保存6个月。加工对叶绿素和类胡萝卜素色素的含量有显著影响；然而，新鲜、冷冻菠菜中各品种色素总量及单一色素含量并无差异。由于脱镁叶绿素化，热烫时间延长导致叶绿素a和b含量降低，叶绿素a'和b'以及脱镁叶绿素a和b含量增加。只有在热烫15分钟后才能检测到因脱镁叶绿素化引起的颜色变化。热烫过程中类胡萝卜素色素比叶绿素色素更稳定。（全-E）-紫黄质显著减少，这是由于在热烫过程中降解为其他叶黄素，如新叶黄素。干燥菠菜和热烫冷冻菠菜的叶绿素a和b含量没有显著差异。干燥后观察到叶绿素a'和b'、脱镁叶绿素a和b以及叶绿素a-1和b-1的形成。干燥样品中脱镁叶绿素a和b的含量明显低于热烫冷冻样品。在空气中保存的干燥菠菜中，β-胡萝卜素含量[599毫克/千克干物质（DM）]显著低于氮气保存的（766毫克/千克DM），且（全-E）-叶黄素含量低于热烫冷冻菠菜。新鲜菠菜中未检测到新叶黄素，但在蒸汽热烫和干燥菠菜中可检测到。在热烫3分钟后冷冻保存的菠菜和干燥菠菜之间，（全-E）-新黄质、（9'Z）-新黄质、（全-E）-紫黄质、（全-E）-叶黄素环氧化物或新叶黄素A和B的含量没有差异。
