Turmeric (Curcuma longa L.) is a rhizome plant that has long been used by
Indonesian people as a cooking spice and raw material for traditional medicine. The
main active compound in turmeric is curcumin which gives a characteristic yellow
color and has various health benefits, including antioxidant, anti-inflammatory, and
antimicrobial activities.
This study aims to identify functional groups in the active compound curcuminoid
and the differences in infrared spectrum patterns aimed at the spectrum patterns of the
quadrants produced in commercial turmeric powder products sold in the market using
infrared spectrophotometry methods. Samples of commercial turmeric powder
products were collected from 10 traditional markets and analyzed using Attenuated
Total Reflection Fourier Transform Infra Red ATR-FTIR. The results of the
interpretation of peak wave numbers from the FTIR spectra were analyzed using
Principle Component Analysis (PCA) to determine Principle Component 1 and 2 then
the FTIR spectra patterns analyzed with Minitab software produced a score plot with
4 quadrants. Similar FTIR spectra patterns will be in the same quadrant.
The results of the analysis of 10 samples of commercial turmeric powder
products tested showed differences in the FTIR spectral profiles indicating variations
in the quality and purity of pure turmeric powder by identifying the presence of
functional groups of turmeric characteristic marker compounds, especially
curcuminoids. The results of the FTIR spectral analysis with PCA showed that turmeric
powder from Condongcatur Market, Ngasem Market, Sambilegi, Sorogenen, Kutu,
Maguwoharjo, and Beringharjo had FTIR spectral patterns similar to powder from
pure turmeric rhizomes located in quadrant 2. The FTIR spectral patterns of turmeric
powder from Gowok Ambarukmo and Colombo Markets located in quadrant 1, as well
as the FTIR spectral pattern of Sentul Market located in quadrant 3 had different FTIR
spectral patterns from pure turmeric powder.