Near-infrared System Research Articles

Towards the in-forest Assessment of Kraft Pulp Yield: Comparing the Performance of Laboratory and Hand-Held Instruments and Their Value in Screening Breeding Trials

The non-destructive prediction of Kraft pulp yield in standing trees using near infrared (NIR) spectroscopy has been typically performed by removing 5 mm or 12 mm increment cores from candidate trees in the forest and returning the samples to the laboratory for analysis. It would be desirable to perform in-field prediction using a portable NIR device; for example, to rapidly screen individual trees in a breeding trial prior to selecting trees for further sampling. This paper compares the performance of a laboratory-based full-range Fourier transform NIR system with two portable NIR devices operating at two different spectral ranges (950–1800 nm and 1600–2400 nm). Calibrations, explaining commercially useful amounts of variance in Kraft pulp yield ( R2 = 0.85–0.94) and cellulose content ( R2 = 0.92–0.96), were developed for the laboratory NIR and both hand-held portable NIR instruments using woodmeal. This demonstrates that the wavelength range and resolution of the portable instruments are suitable for the prediction of Kraft pulp yield and cellulose content. In an initial in-forest trial, calibration of Kraft pulp yield ranged between R2 = 0.4–0.6 across two sites and two sampling periods. While there are still a number of in-forest sampling issues to be resolved around seasonal sampling, the implication is that low-cost, hand-held NIR systems are a feasible alternative to laboratory-based NIR systems for routine assessment of Kraft pulp yield.

Determination of Basic Density and Moisture Content of Loblolly Pine Wood Disks Using a near Infrared Hyperspectral Imaging System

The use of near infrared (NIR) hyperspectral imaging for the estimation of basic density (BD) and moisture content (MC) of loblolly pine ( Pinus taeda L.) disks is reported. A total of 125 wood disks, ranging in age from 13 years to 19 years, were analysed. Hyperspectral images were collected using an imaging system composed of an InGaAs camera from Sensors Unlimited, Inc. (sensitive between 1000nm and 1700nm at 5nm increments) and a Liquid Crystal Tunable Filter from CRI, Inc., continuously tunable between 1000 nm and 1800 nm. Owing to noise, spectra were truncated to 1005–1645nm and smoothed using a five-point median filter prior to calibration development. Sixteen samples were detected as outliers, reducing the number of disks available for analysis to 109, which were subsequently split into calibration (85) and validation (24) sets. Successful models, based on the hyperspectral data, were obtained for disk basic density ( R2c=0.81) and moisture content ( R2c=0.77). The predictive ability of the calibrations was acceptable, with root mean square errors ( RMSEP) of 23.6 kg m−3 for BD and 2.1% for MC. The calibrations were compared to those obtained using NIR spectra collected from the surface of the disks using a Foss XDS NIR System coupled with a Smart Probe Analyser using the same wavelength range and number of samples (each disk was represented by an average of eight spectra which had been divided into four quadrants with two spectra collected per quadrant). Probe-based calibrations were more successful; however, the hyperspectral-based calibrations were of sufficient strength to suggest that hyperspectral imaging could be used for the estimation of BD and MC of loblolly pine disks.

Frontal Cortical Connectivity and Lateralisation of Joint Attention Experience Using near Infrared Spectroscopy

Autism is a socio-communication brain development disorder. It is marked by degeneration in the ability to respond to joint attention skill tasks, from as early as 12 to 18 months of age. This trait is used to distinguish autistic from typically developing populations. In this study, near infrared (NIR) spectroscopy was used for the first time to study brain connectivity and lateralisation in response to joint attention experience in normal adults. The pre- and anterior frontal regions of the brain were non-invasively imaged using a frequency-domains based NIR system. The imaging studies were performed on 11 normal right-handed adults and optical measurements were acquired in response to joint-attention based video clips. Functional connectivity analysis was performed using intensity and relative phase shift data of the frequency-domain optical signals. Functional connectivity was computed using zero-order correlations and the cortical lateralisation analyses was also performed. Strong functional connectivity (in terms of HbO (oxy-haemoglobin), HbT (total haemoglobin) and relative phase shift data) in the pre-frontal cortex, was observed, irrespective of the stimuli (joint-attention (J), non-joint attention (NJ), and baseline rest (R); J, NJ or R). However, in the anterior frontal cortex, although the connectivity (based on HbO and HbT) demonstrated a strong correlation between the left and right regions, the connectivity (based on relative phase shift data) demonstrated a weaker correlation. The cortical lateralisation study demonstrated a right pre-frontal dominance during NJ and R stimuli, and not so in the J stimulus. The lateralisation study complemented the connectivity study by revealing that, although both the volume and pathlengths of the left and right pre-frontal cortex are similar, the dominance can vary with respect to stimuli. The high temporal resolution of NIR spectroscopy enabled study of the neural pathway associated with the socio-communicative skills, and hence the results have potential to elucidate the neural pathways associated with autism. Future NIR studies on autistic and typically developing children in response to the socio-communicative tasks (e.g. joint attention experience), may have a significant impact in early stage diagnostic intervention of autism in much younger children (< three years of age).

Determination of Basic Density and Moisture Content of Merchantable Loblolly Pine Logs by near Infrared Spectroscopy

The use of near infrared (NIR) diffuse reflectance spectroscopy for the estimation of basic density and moisture content of loblolly pine ( Pinus taeda L.) logs was explored. A total of 219 wood disks representing the large and small ends of 146 merchantable logs 4.87 m in length, ranging in age from 13 years to 19 years, were analysed. NIR spectra were obtained from the transverse surface of the disks when the wood was green using a Foss XDS NIR System coupled with a Smart Probe Analyser. Each disk was divided into four quadrants and two spectra were collected per quadrant (one representing juvenile wood and one mature wood). NIR calibration models were fitted using pre-processed spectra with multiplicative scatter correction and the dimensionality of the models was kept constant for comparison purposes. Successful models based on an average of all spectra collected from both ends of the logs were obtained for basic density ( R2c = 0.84) and moisture content ( R2c = 0.85) using nine factors for both properties. The predictive ability of the calibrations was acceptable, with mean square errors of 22.8 kg m−3 for basic density and 2.1% for moisture content. It was found that the number of spectra per disk could be reduced to four readings but further reductions increased prediction errors considerably. Calibration models based only on spectra collected from one of the log ends were also examined. Using large-end diameter spectra only, the fit statistics for basic density models fell to R2 c=0.76 for (eight spectra) and R2c=0.71 (four spectra). Similarly, the fit statistics for moisture content calibrations dropped to R2c=0.76 for (eight spectra) and R2c=0.72 (four spectra). Calibrations based only on small-end diameter spectra were considerably weaker than those based on large-end diameter spectra.

Rapid Noninvasive Continuous Monitoring of Oxygenation in Cerebral Ischemia and Hypoxia

The brain is most sensitively dependent on oxygen to maintain its normal function. Methods to assess the degree of its oxygenation have generally been invasive and indirect. Rapid assessment of brain oxygenation is particularly vital during cerebrospinal ischemia and hypoxia. We have developed a noninvasive electro-optical method using pulsed near-infrared (NIR) light to quantify brain oxygenation during ischemia and hypoxia in anesthetized rabbits. Cerebral ischemia was induced through 30-40s of bi-lateral carotid artery occlusion. Cerebral hypoxia was induced by varying inspired oxygen levels. The NIR light response to the interventions was expressed in terms of relative absorption (RA). Results showed that our pulsed NIR system could rapidly detect sudden alterations in oxygenation and blood flow to the brain. The response patterns during cerebral ischemia and hypoxia were significantly different, although both decreased brain oxygenation. The overall RA response to ischemia was much faster (in seconds) than during hypoxia (in minutes). These different response patterns can serve as early warning signal of low brain oxygenation and to discriminate the cause of the diminished oxygenation. The present pulsed NIR system is capable to provide a rapid, noninvasive and continuous monitoring of such decreases in brain oxygenation.

Intraoperative near-infrared image-guided surgery for peritoneal carcinomatosis in a preclinical experimental model

This study compared the quality of surgery performed under conventional light with near-infrared (NIR) image-guided surgery using a tumour-targeting probe and a portable clinical grade imaging device in a mouse model of peritoneal carcinomatosis. Peritoneal carcinomatosis was induced by injection of luciferase-positive tumour cells, leading to the formation of small nodules in the peritoneal cavity. One day after intravenous injection of RAFT-c(RGDfK)4-Alexa Fluor 700, a fluorescent tumour-targeting probe, the surgeon operated using the Fluobeam, a portable device that illuminated the mouse with NIR light and allowed NIR vision. The quality of the surgery was evaluated using bioluminescence, a highly sensitive method that detected the remaining tumour cells, and operating time was measured. Under normal light, the surgeon detected and removed a mean(s.d.) of only 50.6(2.3) per cent of the nodules that were visible under NIR light. The duration of surgery was reduced from 19.5(3.3) min under normal light to 14.0(2.6) min when NIR light was used (P = 0.025). The sensitivity of the NIR system allowed the detection of nodules containing as few as 227 tumour cells. NIR image-guided surgery improved the quality of surgery for peritoneal carcinomatosis by doubling the number of nodules detected and significantly reducing the duration of surgery.

Detection of wet-pockets on the surface of Tsuga heterophylla (Raf.) Sarg. by near infrared (NIR) spectroscopy

Abstract Multivariate statistical models capable of rapidly and accurately predicting the surface moisture content in Tsuga heterophylla were developed based on near infrared (NIR) spectra of small specimens precisely conditioned within the hygroscopic range. In an initial research phase, the applicability of NIR as predictor of surface moisture was investigated. The first derivative spectra in the range of 1300–2100 nm yielded the best results. The partial least squares regression (PLS-1) model had coefficient of determination (R2) of 0.98, root mean square error of cross validation (RMSECV) of 0.97%, root mean square error of prediction (RMSEP) of 1.05%, and ratio of performance to deviation (RPD) of 7.25. In a subsequent phase, an inline pilot-plant NIR system combined with this PLS-1 model was constructed. The prediction ability of the NIR system was tested with line speeds of 0, 100, 200, and 400 mm s-1 on kiln-dried full-length lamination boards classified as “wets” after conventional kiln drying. In a calibrated range of moisture content (0–25.4%), the NIR system demonstrated R2 values of 0.79 and 0.74, RMSEP values of 3.13 and 3.28, and RPD values of 2.18 and 1.67 at a line speed of 0 and 100 mm s-1, respectively, regardless of the presence of knots and surface roughness. These results demonstrate that the NIR system at a line speed of 0–100 mm s-1 could be used to provide entire surface moisture distribution and to detect local moisture peaks that indicate surface wet-pockets in kiln-dried lumber destined for lamination.

Technical Note: Measuring Grain and Insect Characteristics Using NIR Laser Array Technology

The potential of using a compact eight-wavelength near-infrared (NIR) laser array spectrometer for measuring wheat characteristics (hardness index, moisture content, and waxy character) and determining tsetse fly pupae sex was investigated and compared to a commercial single kernel near infrared (SKNIR) system. Wheat hardness was predicted accurately by both NIR systems and results were in close agreement with reference values. The accuracy of predicting moisture content by either system was similar with predicted values within 0.5% moisture content of the reference values. Waxy character was predicted by the laser system with less accuracy than the SKNIR system, but tsetse fly pupae sex was predicted with similar accuracies for both systems. Prediction equations derived from the laser spectra show that wavelengths influencing classification models generally agree with published literature. Thus, this research shows that a NIR laser array system can be used to predict some grain and insect traits with accuracy similar to a commercial NIR system and some predictions may be improved if other wavelengths are used in the laser array system.

Near-infrared Fourier-transform and millimeterwave spectra of the BiS radical

This paper reports the 6400–7400 cm −1 Fourier-transform (FT) near-infrared (NIR) emission spectrum of the BiS X 2 2Π 3/2 → X 1 2Π 1/2 fine structure bands as well as the millimeterwave rotational spectrum of the X 1 2Π 1/2 state. For the FTNIR observations, BiS was produced by reaction of bismuth with sulfur vapor and excited by energy transfer from metastable oxygen, O 2( a 1Δ g ), in a fast-flow system. As was the case for BiO [O. Shestakov, R. Breidohr, H. Demes, K.D. Setzer, E.H. Fink, J. Mol. Spectrosc. 190 (1998) 28–77], the 0.5 cm −1resolution spectrum revealed a number of strong bands in the Δv = 0 and ±1 sequences which showed perturbed band spacings, band shapes, and intensities due to avoided crossing of the X 2 2Π 3/2 and A 1 4Π 3/2 potential curves for v ′ ⩾ 4 of X 2 2Π 3/2. The millimeterwave rotational spectrum of BiS in its X 1 2Π 1/2 state was observed when BiS was produced in a high-temperature oven by a discharge in a mixture of Bi vapor and CS 2. The signal to noise ratio was markedly improved by using a White-type multipath cell. Ninety seven features from J′ = 23.5 to J′ = 41.5 were measured between 150 and 300 GHz. Analysis of the 0.5 cm −1 resolution FT spectrum yielded the fine structure splitting and vibrational constants of the states. A simultaneous analysis of millimeterwave and a 0.005 cm −1 FT spectrum of the 0-0 band of the NIR system was carried out to give precise rotational, fine, and hyperfine constants for the X 1 2Π 1/2 and X 2 2Π 3/2 states. The results are consistent with those reported earlier for BiO and indicate only a slight decrease in the unpaired electron density in the 6p(π ∗) orbital on the Bi atom.

The US Pharmacopeia near Infrared System Suitability Reference Standard

The United States Pharmacopeia (USP) General Chapters Expert Committee revised the General Information Chapter Near-Infrared Spectrophotometry <1119> in 2004 and introduced a USP Near Infrared (NIR) Calibrator Reference Standard (RS), which, in accordance with metrological principles was renamed the USP NIR System Suitability RS. The RS is intended for the qualification of NIR instrument wavelength uncertainty when measurements are taken in diffuse reflectance mode. The USP NIR System Suitability RS is a mixture of three rare earth oxides—dysprosium (Dy2O2), holmium (Ho2O3) and erbium (Er2O3)—plus talc [Mg3Si4O10(OH)2] in a 1: 1: 1: 1 ratio. This System Suitability RS was tested according to metrological principles based on International Organisation for Standardisation guidances during collaborative tests that established its suitability for use and reproducibility. This RS yields eight reference peaks that cover the spectral range between 1000 nm (10,000 cm−1) and 2500 nm (4000 cm−1) and are reported in an accompanying certificate. Analysts thus can use the USP NIR System Suitability RS for performance verification (i.e. to determine instrument wavelength uncertainty) when they operate NIR instruments in diffuse reflectance mode. This paper reviews the characteristics and metrologically informed development of the USP NIR system suitability RS for diffuse reflectance measurements and discusses the suitability of the RS for qualifying NIR instruments operating in the diffuse reflectance mode.

System Design for Non-Destructive near Infrared Analyses of Chemical Components and Total Aerobic Bacteria Count of Raw Milk

In order to develop a system for quality and safety evaluation of non-homogenised raw milk using near infrared (NIR) spectroscopy, two stages of research have been conducted. The first stage was the development of a compact NIR system for measuring the major constituents such as fat and protein in an aseptic environment. The second stage was the measurement of the total aerobic bacteria count (TBC). In the first stage, two compact sample holders for commercially-available capped test tube were designed. One system was equipped with an NIRSystem6500 research-type NIR spectrophotometer, hereafter referred to as MilkSpec-2. The other was equipped with a hand-held NIR spectrophotometer, the FT20, hereafter referred to as MilkSpec-3. For MilkSpec-2, the highly satisfactory results were obtained with the multiple determination coefficients of determination ( R2) = 0.99 and 0.96, and standard errors of prediction (SEP) = 0.03% and 0.07% for fat and protein, respectively. The results for MilkSpec-3 were also satisfactory but inferior compared with MilkSpec-2; the results were R2 = 0.99 and 0.91 and SEP=0.06% and 0.08% for fat and protein, respectively. In the following stage, MilkSpec-2 was used for the measurement of TBC in terms of log colony forming units (CFU) mL−1. In the case of TBC measurements, where the concentration of bacteria itself or its by-products were very low, three kinds of commercial test tube made of the same kind of glass but differing in diameter were used to identify the appropriate physical pathlength. It was found that the medium sized test tube with an external diameter of 20 mm provided the best calibration results with R2 = 0.83, SEP = 0.55 log (CFU) mL−1 and the ratio of standard deviation of reference data in the validation set to SEP (RPD) = 2.33. The analysis of the calibration structure indicated that the information related to absorptions by bacteria metabolites such as lactic acid, urea and those of the carbon sources such as lactose and protein in milk might play substantial roles in the NIR-TBC determination.

Near-infrared multivariate calibration updating using placebo: A content uniformity determination of pharmaceutical tablets

This paper presents an application of near-infrared (NIR) multivariate calibration for the determination of content uniformity of pharmaceutical tablets. Data used in this study were acquired from 3 NIR instruments obtained from 2 different vendors. One of these spectrometers is a dispersive NIR system configured for reflectance measurements while the other two, are Fourier transform (FT) based configured for both transmittance and reflectance. The performance of partial least squares (PLS) calibration models generated from the primary instrument (A) was investigated using samples measured on secondary instruments (B and C). The cross-instrument predictions without standardization or updating was not successful in the reflectance mode for both instrument B and C producing root mean square error of prediction (RMSEP) values of 2.78 and 5.78%, respectively. Similar deterioration of the calibration model was evidenced for instrument B in the transmittance mode with an RMSEP value of 2.65%. To minimize the effect of instrument response variations, piecewise direct standardization (PDS) was used. This lowered the RMSEP in the reflectance mode for the secondary instruments B and C to 1.19 and 1.58%, respectively. Similar improvement was obtained in the transmittance mode for instrument B producing RMSEP of 1.12%. For cases in which the stability of drug substance is poor and the on-demand manufacture of transfer samples is difficult, a model updating strategy that uses placebo samples is proposed. This technique also outperformed the direct cross-instrument predictions with RMSEP values of 1.25 and 1.70% for instruments B and C, respectively, in the reflectance mode and 1.42% for instrument B in the transmittance mode.

Predicting beef tenderness using near-infrared spectroscopy1

The objective of this multiple-phase study was to determine the accuracy of an on-line near-infrared (NIR) spectral reflectance system to predict 14-d-aged cooked beef tenderness. In phase I, 292 carcasses (140 US Select, 152 US Choice) were selected (d 2) from 2 commercial beef processing facilities. After carcass selection, longissimus lumborum (LL) muscle sections (ribs 9 to 12) were individually identified, vacuum-packaged, and transported to the Oklahoma State University Meats Laboratory, where a 2.54-cm-thick steak (n = 1) was fabricated and stored in refrigerated conditions (1 degrees C +/- 1). Following a 30-min oxygenation period, a NIR spectral scan was obtained on the 12th-rib LL steak. Steaks (d 3) were individually vacuum-packaged and aged at 4 degrees C for a total of 14 d before cooking slice shear force (SSF) analysis. In phases II and III, 476 carcasses (258 US Select, 218 US Choice) were immediately NIR scanned after carcass presentation to in-plant USDA grading personnel. In a similar fashion, all LL steaks were aged (1 degrees C +/- 1) for 14 d before cooking (70 degrees C) and conducting SSF. Of the phase I and II samples, 39 (6.77%) were categorized as being tough (i.e., >/= 25 kg of SSF after the 14-d postmortem aging period). Of these 39 tough samples, 20 (3.7% error rate) were correctly placed in the 90% certification level. Another 10 tough samples were placed in the 80% certification level (2.0% error rate). The overall NIR certified tender group was 1.67 kg more tender (P < 0.05) than LL samples from the noncertified samples. When the NIR predicted samples to be tough, 10% of the samples were eliminated from the phase I and II LL populations at 90% certification. The population SSF mean improved in excess of 6.5 kg. For phase III, SSF evaluation by an independent third party indicated the NIR system was able to successfully sort tough from tender LL samples to 70% certification levels. It was concluded that NIR scanning offers an in-plant opportunity to sort carcasses into tenderness outcome groups for guaranteed-tender branded beef programs.

Developments in quantitative oxygen-saturation imaging of breast tissue in vivo using multispectral near-infrared tomography.

Imaging of oxygen saturation provides a spatial map of the tissue metabolic activity and has potential in diagnosis and treatment monitoring of breast cancer. Oxygen-saturation imaging is possible through near-infrared (NIR) tomography, but has low signal-to-noise ratio (SNR). This can be augmented by using NIR tomography as an add-on to MRI. Presented are results from a free-standing NIR system and a hybrid MR-guided system for breast imaging. In results from imaging 60 healthy volunteers in the initial NIR system, oxygen saturation was a significant discriminator between the BIRADS classifications of adipose tissue, heterogeneously dense, and extremely dense tissue. By using the MR-guided NIR system, more accurate tissue-specific data were obtained on adipose and fibroglandular volumes, with 11 healthy volunteers. In these data, oxygen saturation in the adipose tissue correlated with percentage of adipose tissue. In two case studies of infiltrating ductal carcinomas, oxygen saturation was reduced at the site of the tumor, as compared with the surrounding healthy tissue, agreeing with conventional thought that hypoxia exists in larger solid tumors. The MRI-guided NIR images of oxygen saturation provide higher resolution and superior SNR and will likely be used in the future to study and characterize specific tissue volumes.

Simple and Rapid Quantitative Determination of Di(2-ethylhexyl)phosphoric Acid Concentration Using Near Infrared Spectroscopy

were the conventional method reported for the determination of DEHPA, while the spectrophotometric analysis of DEHPA in an organic solvent has not been taken into account. Total organic carbon method as a general quantitative determination tool for most organic materials cannot be used in organic media such as hexane. Despite the disadvantages of requiring the time-consuming calibration and validation with plenty of samples as well as a proper understanding of chemometric techniques in near infrared (NIR) technique for industrial applications, practically useful instrumentations such as attractive portable NIR system have been suggested recently. 7 In this study, common glass vial was used for the convenient NIR quantification of DEHPA in the presence of the interference from a solvent absorption by using NIR spectroscopic technique equipped with a user-friendly commercial software for a multivariate calibration. This will be technically useful for various field applications. Simple wavelength selection and effect of pathlength were also investigated.

Pedestrian Detection with Night Vision Systems Enhanced by Automatic Warnings

Pedestrian detection using far-infrared (FIR) and near-infrared (NIR) night vision systems was compared in this experiment, combined with automatic warnings at one of two distances (150 m and 75 m) or no warning at all. Sixteen subjects (eight younger than 30 years and eight older than 60 years) pressed a button as soon as they saw a pedestrian on a night vision system in the center console of a vehicle simulator. In addition, they performed a concurrent simulated steering task that required almost continuous viewing of the forward scene, similar to real driving. The automatic visual warning was a blue rectangle that zoomed in on the pedestrian in the video display. When the warning was presented 150 m ahead of the pedestrian, detection distance and accuracy for both night vision systems increased, but the effects were more prominent for the NIR system. In the 75 m condition, automatic warnings improved performance with NIR but worsened performance with FIR, possibly because in some trials subjects waited for the automatic warning before responding. Overall, automatic visual warnings based on image processing were effective in increasing accuracy and detection distance for pedestrians except when short-distance warnings were used with the FIR system.

An Automated Near‐Infrared System for Selecting Individual Kernels Based on Specific Quality Characteristics

ABSTRACTAn automated sorting system was developed that nondestructively measured quality characteristics of individual kernels using near‐infrared (NIR) spectra. This single‐kernel NIR system was applied to sorting wheat (Triticum aestivum L.) kernels by protein content and hardness, and proso millet (Panicum miliaceum L.) into amylose‐bearing and amylose‐free fractions. Single wheat kernels with high protein content could be sorted from pure lines so that the high‐protein content portion was 3.1 percentage points higher than the portion with the low‐protein kernels. Likewise, single wheat kernels with specific hardness indices could be removed from pure lines such that the hardness index in the sorted samples was 29.4 hardness units higher than the soft kernels. The system was able to increase the waxy, or amylose‐free, millet kernels in segregating samples from 94% in the unsorted samples to 98% in the sorted samples. The portion of waxy millet kernels in segregating samples was increased from 32% in the unsorted samples to 55% after sorting. Thus, this technology can be used to enrich the desirable class within segregating populations in breeding programs, to increase the purity of heterogeneous advanced or released lines, or to measure the distribution of quality within samples during the marketing process.

Determination of Water Content in Ethanol by Miniaturized Near-Infrared (NIR) System

The miniaturized NIR (Near-infrared) spectrometer has been utilized for the determination of water content (1-19% range) in ethanol that is the most popular organic solvent in pharmaceutical industries. It has many potential capabilities that can replace the conventional analyzers especially for the on-line measurement since it is compact, versatile and cost-effective. By using two dimensional (2D) correlation spectroscopy, it was preliminarily investigated to find any unforeseen spectral distortion among the spectra collected from the miniaturized spectrometer. The 2D study revealed that the spectral variation clearly followed the variation of water concentration without any spectral distortion or abnormality. PLS (Partial Least Squares) was employed to build the calibration model and the resulting prediction performance was acceptable and stable over several days. Even though the miniaturized NIR system was evaluated to fairly simple chemical matrix, the overall study demonstrates the sufficient feasibility for diverse practical and industrial applications.

Milk-quality monitoring by near-infrared spectroscopy for artificial intelligence in dairy farming

Abstract A near-infrared (NIR) spectroscopic sensing system was constructed on an experimental basis. This system enables NIR spectra of unhomogenized milk to be obtained during milking over a wavelength range of 600 to 1050 nm. The NIR system can be used forreal-time monitoring of fat, protein, lactose, somatic cell count, and milk urea nitrogen during milking with sufficient precision and accuracy. By using this NI Rsystem, dairy farm management could proceed to the next step in the transition to artificial intelligence in dairy farming based on information of each individual cow.

On-Tree Evaluation of Harvesting Quality of Mango Fruit Using a Hand-Held NIR Instrument

An on-site system was established for determining the maturity of hard green mangoes that are consumed later when ripened off the tree. A hand-held near infrared (NIR) instrument operating in the short wavelength region was used for spectral acquisition. The effect of sunlight on spectra measured outdoors was described and removed. The NIR measuring system developed was used for predicting dry matter (DM) and starch content in hard green mangoes prior to harvest. On the 2D-scatter plot between predicted DM and starch content, the fully-mature hard green mangoes, with excellent eating quality when ripe, could be completely separated from the immature ones, with unacceptable eating quality when ripe. The feasibility of in vivo monitoring of internal composition changes was demonstrated. It was concluded that the NIR system was sufficiently capable of determining maturity stages of hard green mangoes on trees. The system could be used as a tool for a grower to decide a proper harvesting date that will provide high-quality fresh fruit to consumers.