ANALISIS KUALITATIF DAN KUANTITATIF NITRIT DAN NITRAT DALAM IKAN ASIN

• Main Author: Febriyana, Lolita
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/44939
• Institution: Institut Teknologi Bandung

From the view of food safety, nitrite and nitrate may present in food products belong to chemical hazard source. Due to degradation processes, dried fish may contain nitrite and nitrate as chemical contaminants. The purpose of this research was to obtain an analytical method for identification and determination of nitrite and nitrate in dried fish by means of visible spectrophotometric method. Nitrite was reacted with sulfanilic acid to a diazonium salt and subsequently coupled with N-1-naphthyl-ethylenediaminedihydrochloride (NED) to give reddish violet colored solution measureable at 545 nm. Nitrate was reacted with salicylic acid under acidic condition to form nitro substituted salicylic acid giving yellow colored solution under basic condition measureable at 420 nm. Validation parameters such as linearity, limit of detection, limit of quantification, precision and accuration were also determined. The two methods gave a linear calibration curves in concentration range of 0.667 to 3.999 ppm with an equation of 0.0362 x + 0.1825 and coefficient correlation (r) of 0.9999756, for nitrite, while that of nitrate in concentration range of 18.414 to 49.104 ppm with an equation of 0.01 x + 0.0406 and coefficient correlation (r) of 0.99962. Limit of detection (LOD) for nitrite and nitrate were 0.032 and 1.363 ppm, while limit of quantification (LOQ) for nitrite and nitrate were 0.0956 and 4.13 ppm, respectively. The average coefficient of variation (CV) for intraday precision of nitrite and nitrate were 1.28% and 1.23%, while those of interday precision were 1.35% and 1.24%, respectively. The average percentge of recovery for nitrite and nitrate were 100.37% and 99.02%. Applying the method, 10 commercial samples of dried fish were identified to contain nitrite and nitrate at the concentration levels were 1.584 – 31.814 µg/g and 105.8 – 261.667 µg/g, respectively. Based on those result, the method for identification and determination of nitrite and nitrate in dried fish by means of visible spectrophotometric technique was successfully obtained.