Detection of melamine in milk powders using near-infrared hyperspectral imaging combined with regression coefficient of partial least square regression model

Lim, Jongguk,Kim, Giyoung,Mo, Changyeun,Kim, Moon S.,Chao, Kuanglin,Qin, Jianwei,Fu, Xiaping,Baek, Insuck,Cho, Byoung-Kwan Elsevier 2016 Talanta Vol.151 No.-

<P><B>Abstract</B></P> <P>Illegal use of nitrogen-rich melamine (C<SUB>3</SUB>H<SUB>6</SUB>N<SUB>6</SUB>) to boost perceived protein content of food products such as milk, infant formula, frozen yogurt, pet food, biscuits, and coffee drinks has caused serious food safety problems. Conventional methods to detect melamine in foods, such as Enzyme-linked immunosorbent assay (ELISA), High-performance liquid chromatography (HPLC), and Gas chromatography–mass spectrometry (GC–MS), are sensitive but they are time-consuming, expensive, and labor-intensive. In this research, near-infrared (NIR) hyperspectral imaging technique combined with regression coefficient of partial least squares regression (PLSR) model was used to detect melamine particles in milk powders easily and quickly. NIR hyperspectral reflectance imaging data in the spectral range of 990–1700nm were acquired from melamine-milk powder mixture samples prepared at various concentrations ranging from 0.02% to 1%. PLSR models were developed to correlate the spectral data (independent variables) with melamine concentration (dependent variables) in melamine-milk powder mixture samples. PLSR models applying various pretreatment methods were used to reconstruct the two-dimensional PLS images. PLS images were converted to the binary images to detect the suspected melamine pixels in milk powder. As the melamine concentration was increased, the numbers of suspected melamine pixels of binary images were also increased. These results suggested that NIR hyperspectral imaging technique and the PLSR model can be regarded as an effective tool to detect melamine particles in milk powders.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Melamine particles contained in milk powder were detected by NIR hyperspectral imaging. </LI> <LI> Regression coefficient values were used to reconstruct the PLS images. </LI> <LI> PLS images were used to discriminate the melamine pixels from milk powder pixels. </LI> <LI> Melamine particles at 200ppm in milk powder were confirmed without pretreatment. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Non-destructive profiling of volatile organic compounds using HS-SPME/GC-MS and its application for the geographical discrimination of white rice

Lim, Dong Kyu,Mo, Changyeun,Lee, Dong-Kyu,Long, Nguyen Phuoc,Lim, Jongguk,Kwon, Sung Won The Journal of Food and Drug Analysis (JFDA), Food 2018 JOURNAL OF FOOD AND DRUG ANALYSIS Vol.26 No.1

<P>The authenticity determination of white rice is crucial to prevent deceptive origin labeling and dishonest trading. However, a non-destructive and comprehensive method for rapidly discriminating the geographical origins of white rice between countries is still lacking. In the current study, we developed a volatile organic compound based geographical discrimination method using headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME/GC-MS) to discriminate rice samples from Korea and China. A partial least squares discriminant analysis (PLS-DA) model exhibited a good classification of white rice between Korea and China (accuracy = 0.958, goodness of fit = 0.937, goodness of prediction = 0.831, and permutation test p-value = 0.043). Combining the PLS-DA based feature selection with the differentially expressed features from the unpaired t-test and significance analysis of microarrays, 12 discriminatory biomarkers were found. Among them, hexanal and 1-hexanol have been previously known to be associated with the cultivation environment and storage conditions. Other hydrocarbon biomarkers are novel, and their impact on rice production and storage remains to be elucidated. In conclusion, our findings highlight the ability to rapidly discriminate white rice from Korea and China. The developed method maybe useful for the authenticity and quality control of white rice. Copyright (C) 2017, Food and Drug Administration, Taiwan. Published by Elsevier Taiwan LLC.</P>

The integration of multi-platform MS-based metabolomics and multivariate analysis for the geographical origin discrimination of Oryza sativa L.

Lim, Dong Kyu,Mo, Changyeun,Lee, Jeong Hee,Long, Nguyen Phuoc,Dong, Ziyuan,Li, Jing,Lim, Jongguk,Kwon, Sung Won Elsevier Science B.V., Amsterdam 2018 JOURNAL OF FOOD AND DRUG ANALYSIS Vol.26 No.2

Non-destructive and Rapid Prediction of Moisture Content in Red Pepper (Capsicum annuum L.) Powder Using Near-infrared Spectroscopy and a Partial Least Squares Regression Model

Lim, Jongguk,Mo, Changyeun,Kim, Giyoung,Kang, Sukwon,Lee, Kangjin,Kim, Moon S.,Moon, Jihea Korean Society for Agricultural Machinery 2014 바이오시스템공학 Vol.39 No.3

Purpose: The aim of this study was to develop a technique for the non-destructive and rapid prediction of the moisture content in red pepper powder using near-infrared (NIR) spectroscopy and a partial least squares regression (PLSR) model. Methods: Three red pepper powder products were separated into three groups based on their particle sizes using a standard sieve. Each product was prepared, and the expected moisture content range was divided into six or seven levels from 3 to 21% wb with 3% wb intervals. The NIR reflectance spectra acquired in the wavelength range from 1,100 to 2,300 nm were used for the development of prediction models of the moisture content in red pepper powder. Results: The values of $R{_V}{^2}$, SEP, and RPD for the best PLSR model to predict the moisture content in red pepper powders of varying particle sizes below 1.4 mm were 0.990, ${\pm}0.487%$ wb, and 10.00, respectively. Conclusions: These results demonstrated that NIR spectroscopy and a PLSR model could be useful techniques for measuring rapidly and non-destructively the moisture content in red pepper powder.

Development of Models for the Prediction of Domestic Red Pepper (Capsicum annuum L.) Powder Capsaicinoid Content using Visible and Near-infrared Spectroscopy

Lim, Jongguk,Mo, Changyeun,Kim, Giyoung,Kim, Moon S.,Lee, Hoyoung Korean Society for Agricultural Machinery 2015 바이오시스템공학 Vol.40 No.1

Purpose: The purpose of this study was to non-destructively and quickly predict the capsaicinoid content of domestic red pepper powders from various areas of Korea using a pungency measurement system in combination with visible and near-infrared (VNIR) spectroscopic techniques. Methods: The reflectance spectra of 149 red pepper powder samples from 14 areas of Korea were obtained in the wavelength range of 450-950 nm and partial least squares regression (PLSR) models for the prediction of capsaicinoid content were developed using area models. Results: The determination coefficient of validation (RV2), standard error of prediction (SEP), and residual prediction deviation (RPD) for the capsaicinoid content prediction model for the Namyoungyang area were 0.985, ${\pm}2.17mg/100g$, and 7.94, respectively. Conclusions: These results show the possibility of VNIR spectroscopy combined with PLSR models in the non-destructive and facile prediction of capsaicinoid content of red pepper powders from Korea.

Optimized Mass Spectrometry-Based Metabolite Extraction and Analysis for the Geographical Discrimination of White Rice (Oryza sativa L.): A Method Comparison Study

Lim, Dong Kyu,Long, Nguyen Phuoc,Mo, Changyeun,Dong, Ziyuan,Lim, Jongguk,Kwon, Sung Won Oxford University Press 2018 Journal of AOAC International Vol.101 No.2

<B>Abstract</B><P>In this study, we examined the effects of different extraction methods for the GC-MS- and LC-MS-based metabolite profiling of white rice (Oryza sativa L.). In addition, the metabolite divergence of white rice cultivated in either Korea or China was also evaluated. The discrimination analysis of each extraction method for white rice from Korea and China and the corresponding discriminatory markers were estimated by unpaired t-test, principal component analysis, k-means cluster analysis, partial least-squares discriminant analysis (PLS-DA), and random forest (RF). According to the prediction parameters obtained from PLS-DA and RF classifiers as well as features that could be identified, the extraction method using 75% isopropanol heated at 100°C coupled with LC-MS analysis was confirmed to be superior to the other extraction methods. Noticeably, lysophospholipid concentrations were significantly different in white rice between Korea and China, and they are novel markers for geographical discrimination. In conclusion, our study suggests an optimized extraction and analysis method as well as novel markers for the geographical discrimination of white rice.</P>

Original Article Journal of Biosystems Engineering : Development and Performance Evaluation of Falling-type Dried-Persimmon Weight Sorting System Utilizing Load Cell

( Jongguk Lim ),( Giyoung Kim ),( Changyeun Mo ),( Inchul Choi ) 한국농업기계학회 2015 바이오시스템공학 Vol.40 No.4

Purpose: A falling-type weight sorter equipped with a load cell was developed to sort lightweight dried persimmons. The performance of the sorter was also evaluated. Methods: The electronic weight sorter for dried persimmon comprises a feeder part, a weight-measurement part, an indicator part, a carrier cup, a discharging part, and a driving part. The weight setting and zero-point adjustment are performed digitally for the convenience of users. For the experimental trials, 228 rubber-clay specimens (representative of dried persimmons) in the weight range of 24.73~99.56 g were manufactured for use in experiments to evaluate the performance of the sorter. Results: The average error of the weight measurements from three experimental trials was 1.655%, with a bias of -0.492 g, a root-mean-square error (RMSE) of ±0.808 g, and a coefficient of determination (R(2)) of 0.997. Conclusions: The load-cell-based electronic dried-persimmon weight sorter developed in this study facilitates effective, precise, and convenient sorting of dried persimmons.

Development and Performance Evaluation of Falling-type Dried-Persimmon Weight Sorting System Utilizing Load Cell

Lim, Jongguk,Kim, Giyoung,Mo, Changyeun,Choi, Inchul Korean Society for Agricultural Machinery 2015 바이오시스템공학 Vol.40 No.4

Purpose: A falling-type weight sorter equipped with a load cell was developed to sort lightweight dried persimmons. The performance of the sorter was also evaluated. Methods: The electronic weight sorter for dried persimmon comprises a feeder part, a weight-measurement part, an indicator part, a carrier cup, a discharging part, and a driving part. The weight setting and zero-point adjustment are performed digitally for the convenience of users. For the experimental trials, 228 rubber-clay specimens (representative of dried persimmons) in the weight range of 24.73~99.56 g were manufactured for use in experiments to evaluate the performance of the sorter. Results: The average error of the weight measurements from three experimental trials was 1.655%, with a bias of -0.492 g, a root-mean-square error (RMSE) of ${\pm}0.808g$, and a coefficient of determination ($R^2$ ) of 0.997. Conclusions: The load-cell-based electronic dried-persimmon weight sorter developed in this study facilitates effective, precise, and convenient sorting of dried persimmons.

A rapid and reliable method for discriminating rice products from different regions using MCX-based solid-phase extraction and DI-MS/MS-based metabolomics approach

Lim, Dong Kyu,Mo, Changyeun,Long, Nguyen Phuoc,Lim, Jongguk,Kwon, Sung Won Elsevier 2017 Journal of chromatography. B, Analytical technolog Vol.1061 No.-

<P><B>Abstract</B></P> <P>The expansion of the global rice marketplace ultimately raises concerns about authenticity control. Several analytical methods for differentiating the geographical origin of rice have been developed, yet a high-throughput method is still in demand. In this study, we developed a rapid approach using direct infusion-mass spectrometry (DI-MS) to distinguish rice products from different countries. Specifically, the elimination of the matrix effect by a polytetrafluoroethylene (PTFE) filter, a mixed-mode cation exchange (MCX) solid-phase extraction (SPE) with 20% methanol, and an MCX SPE with 100% methanol were measured. Afterward, partial least squares discriminant analysis and random forests were applied to seek the optimal discrimination method. The results revealed that the combination of MCX SPE with 100% methanol and DI-MS in positive ion mode (accuracy=1.000, R<SUP>2</SUP> =0.916, Q<SUP>2</SUP> =0.720, B/W-based <I>p</I>-value=0.015) or the combination of MCX SPE with 20% methanol and targeted DI-MS/MS in positive ion mode (accuracy=1.000, R<SUP>2</SUP> =0.931, Q<SUP>2</SUP> =0.849, B/W-based <I>p</I>-value=0.002) showed the excellent discriminatory ability. Furthermore, differentially expressed metabolites including sodiated lysophosphatidylcholine, lysophosphatidylcholine, lysophosphatidylethanolamines and lysophosphatidylglycerol classes were found. In conclusion, our study provides a rapid and reliable platform for geographical discrimination of white rice and will contribute to the authenticity control of rice products.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

남은 음식물로 사육되는 동애등에 유충과 혼합물의 표준체 선별

임종국 ( Jongguk Lim ),김밝금 ( Balgeum Kim ),이아영 ( Ahyeong Lee ) 한국농업기계학회 2021 한국농업기계학회 학술발표논문집 Vol.26 No.1

한국환경공단의 2019년도 전국 폐기물 발생 및 처리 현황에 따르면 생활폐기물 중 음식물류의 폐기물(남은 음식물)은 하루 14,314톤이 배출되어 24.7%의 비중을 차지하고 있다. 연간으로는 5,224천톤이며 처리 비용만 2조원 가까이 되어 남은 음식물의 자원화에 대한 중요성이 더욱 부각되고 있다. 남은 음식물들은 소각되거나, 반죽 형태로 제조되어 가축의 사료로 사용되는데 소각시에는 냄새로 인한 문제가 발생되고 있으며 가축의 사료로 사용되는 경우에도 다양한 문제들이 야기될 수 있어 완전한 대안은 아니라고 볼 수 있다. 최근에는 파리목 동애등에과에 속하는 동애등에 곤충의 유충을 이용하여 남은 음식물 처리하기 위한 사료용 곤충의 대규모 사육 공정이 개발되어 점차 확대되고 있다. 동애등에 유충은 사육 환경에 따라 함수율이 높은 상태로 잔존해 있는 음식물과 분변토를 분리하는 과정에서 기존 진동 선별기로는 선별 효율이 낮아 생산 현장에서의 어려움이 커지고 있다. 따라서 본 연구에서는 함수율이 높은 혼합물로부터 동애등에 유충을 효율적으로 분리할 수 있는 분리장치를 개발하기 위해 표준체를 이용하여 사전 분리 정도 실험을 수행하였다. 실험에 사용된 시료는 4개의 대형 사육 트레이에서 수집한 4개의 혼합물을 사용하였으며 표준체는 체눈의 크기가 각각 6.35㎜, 4.00㎜, 2.80㎜. 2.00㎜, 1.40㎜의 5종을 사용하였으면 체진동기를 사용하여 1분 동안 크기 분리를 실시하였다. 동애등에 유충의 밀집도나 혼합물의 함수율 상태에 따라 크기 선별 결과에서 차이가 발생하였다. 대부분의 유충은 2.80㎜체를 기준으로 걸러졌으며 4.00㎜체와 2.00㎜체에도 일부 유충들이 남아있었다. 다만 4.0㎜ 체에는 유충과 함께 유충이 다 분해하지 못한 혼합물이 남아있었고 2.0㎜체에는 크기가 작은 동애등에 유충과 분변토가 혼합되어 재선별이 필요했다. 이번 사전 실험 결과는 추후 동애등에 유충의 분리장치 개발에 있어 체망의 크기 선택, 진동 방식 결정 등의 기초자료로 활용할 수 있을 것이다.