The Effect of Fridge Storing, Cooking and Freezing on the Nitrate and Nitrite Contents of Spinach (Turkish with English Abstract)

Year 2013, Volume: 38 Issue: 1, 9 - 16, 01.02.2013

Aylin Ayaz Mine Yurttagül

Abstract

The aim of this study was to determine the nitrite and nitrate content of spinach samples (n=24). Spinach samples were washed, either stored in refrigerator (aerobic and anaerobic condition), cooked (without water, with water or pre-boiling) or stored in freezer (18 °C, 6 months). The nitrite and nitrate content of spinach was measured by spectrophotometer. Results showed that a low amount of nitrate reduced after washing since nitrate is water soluble (P>0.05). Cooked without water increased the nitrate levels (P>0.05) whereas cooking in water reduced (P<0.05). Storing in refrigerator did not alter the nitrate levels significantly in both aerobic and anaerobic conditions (P>0.05). Both cooked without water (P>0.05) and cooking in water (P<0.05) reduced the nitrite levels. Nitrite levels decreased when spinach was stored in aerobic condition (P<0.05) and increased in anaerobic condition (P>0.05). There was no change in the amounts of nitrate and nitrite in vegetables during freeze storing.

Keywords

Spinach, nitrate, nitrite, storing, cooking, freezing

Ispanakta Buzdolabında Bekletme, Pişirme ve Dondurmanın Nitrat ve Nitrit İçeriğine Etkisi

Abstract

Bu araştırma, Ankara toptancı halinde satışa sunulan ıspanaklara (n: 24) uygulanan farklı işlemlerin; yıkama, buzdolabında bekletme (açık ve kapalı ortamda), pişirme (susuz, suda ve ön haşlama) ve dondurarak depolamanın (-18 oC’de 6 ay depolama) nitrat ve nitrit içeriklerine etkisini belirlemek amacıyla yapılmıştır. Ispanakların nitrat ve nitrit değerleri spektrofotometrik yöntemle analiz edilmiştir. Araştırma sonucunda; nitrat suda çözünen bir bileşik olduğu için yıkama ile miktarının bir miktar azaldığı tespit edilmiştir (P>0.05). Susuz pişirme ile nitrat miktarı artmış (P>0.05), suda pişirme ile azalmıştır (P<0.05). Nitrit miktarları ise, susuz pişirme (P>0.05) ve suda pişirme ile azalmıştır (P<0.05). Buzdolabında açık ve kapalı ortamlarda bekletme ile kuru ağırlıktaki nitrat miktarları arasında önemli bir farklılık bulunmamıştır (P>0.05). Açık ortamda bekletilen ıspanakların nitrit içeriği azalmış (P<0.05), kapalı ortamda bekletilenlerde ise artmıştır (P>0.05). Dondurarak depolama süresince, sebzelerin nitrat ve nitrit içeriğinin değişmediği belirlenmiştir.

Keywords

Ispanak, nitrat, nitrit, bekletme, pişirme, dondurma

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