Submitted to: Food Science and Biotechnology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/8/2012
Publication Date: 4/5/2013
Citation: Mo, C., Lee, K., Lim, J., Kim, M.S., Kang, S., Lee, H., Cho, B. 2013. Development of a pungency measuring system for red-pepper powder. Food Science and Biotechnology. 58(1):137-144. Interpretive Summary: Capsaicinoids are the main chemical compounds that determine the spiciness level of red-pepper powders. Currently, pungency measurement is mostly based on HPLC measurement techniques, which are labor-intensive, time-consuming, and expensive. In this research, a nondestructive on-line pungency measurement method for red-pepper powder was developed using visible to near-infrared spectroscopic methods. The effectiveness of the system was evaluated using powder samples with eleven different spiciness levels, produced by controlling the mixture of predetermined non-spicy and spicy red-pepper powder. The results showed the potential of non-destructive means for rapid on-line measurement of capsaicinoids content in red-pepper powder. The information provided in this paper benefits food technologist, and produce processing industries.
Technical Abstract: Capsaicinoids are the main components that determine the spiciness level of red-pepper powders. Current pungency measurement is mostly dependent on HPLC measurement technique, which is a sample-destructive, labor-intensive, time-consuming, and expensive method. In this research, a nondestructive on-line pungency measurement method for red-pepper powder was developed using a Visible/Near-Infrared spectrometer with the wavelength range of 400 ~ 1050 nm. The system was constructed with a charge-couple device (CCD) spectrometer, a reference measuring unit for calibration, and a sample transfer unit which conveying the red-pepper powder during measurements. Powder samples of eleven different spiciness levels were produced by controlling the mixture of predetermined non-spicy and spicy red-pepper powder. A total 33 different samples, spanning 11 spiciness levels in three particle sizes (below 0.425 mm, 0.425 to 0.71 mm, and 0.71 to 1.4 mm) were prepared for spectral measurements using the developed pungency measuring system. Partial Least Square Regression (PLSR) models were developed to predict the capsaicinoids content from the visible/NIR spectra and reference values measured by HPLC. The RV2 and SEP of the PLSR model for red-pepper powders without regard to particle size were 0.973 and ±6.98 mg/100 g respectively. The best result of the PLSR models (R2 = 0.991, SEP = ± 4.33 mg/ 100 g) was achieved from the raw spectra of red-pepper powders for particle sizes below 0.425 mm. The results show the potential of NIRS technique for non-destructive and on-line measurement of capsaicinoids content in red-pepper powder.