Detection of Formalin in Crisp Squid Using Fourier Transform Infrared Spectroscopy (FTIR)

Abstract

The Fourier Transform Infrared (FTIR) technique has been applied to detect formalin in the crispy ink. The objective of this study is to find new analytical techniques that are friendly with environment, avoid using chemicals. FTIR is the simple fast way and accurate which is convenient for the detection of formalin in food. The crispy squid was bought from the local retailers. A preliminary detection of formalin was performed using a formalin test kit from the Department of Medical Sciences Ministry of Public Health and taken to detect formalin by an infrared spectrometer. The results showed that the infrared spectrum of the crispy squid (no formalin) was found the composition of NH and OH stretching at wavenumber 3308 cm-1, and the amide I peak at 1635 cm-1. By comparing the spectrum of formalin pure with spectrum of the crispy squid contaminated with formalin. It was shown that the formalin peak was deference in the crispy squid contaminated with formalin especially at the wavenumber 1520 cm-1 indicating the absorption of amide II, it was demonstrated formalin destroying structure of proteins in crispy squid. Therefore, from the all above, spectra in ranges of 2970-2920 cm-1, 1570-1520 cm-1, 1460-1240 cm-1 and 1110-1020 cm-1 can be used for identifying formalin in the crispy squid. This study indicated that FTIR was a technique that requires only a minimal sample size avoids the use of chemicals. The process of preparing samples for analysis is not complicated and rapid for the detection of formalin in crispy squid.