摘要:以白蘿卜、胡蘿卜、馬鈴薯、紅薯、山藥、蓮藕為試驗材料,研究不同處理方式對這6種根莖類蔬菜亞硝酸鹽含量的影響。結果表明,相同的洗滌方式下去皮蔬菜的亞硝酸鹽含量更少,不同洗滌方式下亞硝酸鹽含量排序為清水洗滌>果蔬洗滌劑洗滌>用水浸泡15 min;室溫不密封條件下蔬菜的亞硝酸鹽含量較高,且隨天數增加其亞硝酸鹽含量呈一定規律;煮制蔬菜的亞硝酸鹽含量明顯低于烤制,腌制蔬菜的亞硝酸鹽含量呈先降低后上升再降低的趨勢。
關鍵詞:根莖類蔬菜;分光光度法;亞硝酸鹽含量;處理方式
中圖分類號:S63;TS201.6 文獻標識碼: A 文章編號:0439-8114(2013)21-5268-04
Effects of Different Processing Methods on Nitrite Contents in Rootstalk Vegetables
WANG Zi-yun,ZHAN Xiu-huan,GUO Xiao-yun
(Department of Chemistry, Zhoukou Normal University, Zhoukou 466001, Henan, China)
Abstract: White radish,carrot,potato,sweet potato,yam and lotus root were selected to study the effects of different processing methods on their nitrite contents. The results showed the nitrite contents of peeled vegetables were fewer than those of using the same wash method. The nitrite contents under different wash method were as follows: water washing > detergent washing > immersion for 15 min. The nitrite contents of vegetables unsealed and stored at room temperature were higher and correlated with storage time. The nitrite contents in stewed vegetables were fewer than those in baked vegetables. The nitrite contents in pickled vegetables showed the trend of decreasing first and increasing later, and decreasing finally.
Key words: rootstalk vegetables; spectrophtometic method; nitrite contents; processing method
蔬菜是人們日常生活中不可缺少的重要副食品,又是一種容易富集硝酸鹽的作物。研究表明,人體攝入的硝酸鹽81.2%來自蔬菜[1]。亞硝酸鹽是一種氧化劑,進入人體后會使血液中的鐵從低價轉變為高價,從而使血液失去輸氧能力,造成人體血液缺氧中毒,嚴重者可致死[2]。亞硝酸鹽可與次級胺結合成強致癌物亞硝胺,亞硝胺在致癌物中是最令人關注的一類化學致癌物[3],可誘發食道癌、胃癌、肝癌等[4],亞硝酸鹽還可以通過胎盤進入胎兒體內,引起胎兒畸變[5]。據研究,根莖類蔬菜是積累亞硝酸鹽較少的蔬菜類型,王友保等[6]的研究表明蕪湖白蘿卜、馬鈴薯、萵苣的亞硝酸鹽含量遠低于葉菜和果菜。當前蔬菜受亞硝酸鹽污染情形日益嚴重,中國大部分地區蔬菜中亞硝酸鹽的污染已不容忽視。蔬菜中亞硝酸鹽含量的國家標準(GB 15198—1994)為以NaNO2計≤4 mg/kg,以此為依據,調查發現蔬菜中亞硝酸鹽含量存在超標現象[7]。……