Insect Protein Content Analysis in Handcrafted Fitness Bars by NIR Spectroscopy. Gaussian Process Regression and Data Fusion for Performance Enhancement of Miniaturized Cost-Effective Consumer-Grade Sensors
Abstract
:1. Introduction
2. Discussion
2.1. Sensor Suite
2.2. Spectra Pretreatment and Chemometrics
2.3. NIR Spectra of Intact and Prepared Insect Protein Bars
2.3.1. NIR Spectra of Intact Samples
2.3.2. NIR Spectra of Milled Samples
2.4. Comparison of the Analytical Performance of the Benchtop and Miniaturized NIR Spectrometers in the Prediction of the Total Protein Content in Insect Protein Bars
2.4.1. Intact Samples
2.4.2. Milled Samples
2.5. Performance Enhancement of the Cost-Effective Miniaturized NIR Spectrometers by Data Fusion
3. Materials and Methods
4. Summary
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Spectrometer (Vendor) | Key Components | Spectral Region | Resolution [nm] | Connectivity (Data Transfer) | Dimensions [cm] | Weight [g] | |||
---|---|---|---|---|---|---|---|---|---|
Source | Wavelength Selector | Detector | [nm] | [cm−1] | |||||
NIRFlex N-500 (Büchi) | Tungsten halogen (duplicated) | Polarization interferometer (TiO2 wedges) | InGaAs (single-element, thermoelectric cooling) | 800–2500 | 12,500–4000 | ~2 | Ethernet | 45 × 35 × 25 | ca. 35,000 |
MicroNIR 1700 ES (VIAVI) | Tungsten halogen (duplicated) | LVF | InGaAs (array; 128 elements) | 908–1676 | 11,013–5967 | 12.5 | USB—control and power delivery | 5.0 × 4.6 (Ø) | 58 |
Enterprise Scanner NIR-S-G1 (Tellspec) | Tungsten halogen (duplicated) | Stationary dispersive grating and MEMS DMD | InGaAs (single-element) | 900–1700 | 11,111–5882 | 10 | Bluetooth (Cloud service) | 8.2 × 6.3 × 4.0 | 136 |
SCiO (Consumer Physics) | LED | Bandpass filter | Si photodiode (CMOS) array (12 elements) | 740–1070 | 13,514–9346 | Not disclosed | Bluetooth (Cloud service) | 6.8 × 3.9 × 1.5 | 35 |
PLSR | ||||
---|---|---|---|---|
Benchtop | Miniaturized | |||
NIRFlex N-500 | MicroNIR 1700 ES | Tellspec Enterprise Sensor | SCiO Sensor | |
Pretreatment | SG2 (29 SP) | SNV, SG2 (3 SP) | SNV, SG2 (25 SP) | SNV, SG2 (25 SP) |
R2 (Cal) | 0.43 | 0.57 | 0.38 | 0.55 |
R2 (CV) | 0.35 | 0.47 | 0.30 | 0.38 |
RMSEC [%] | 0.641 | 0.557 | 0.668 | 0.568 |
RMSECV [%] | 0.687 | 0.624 | 0.716 | 0.671 |
R2 (TSV) | 0.49 | 0.46 | 0.40 | 0.59 |
RMSEP [%] | 0.611 | 0.620 | 0.659 | 0.545 |
GPR | ||||
Benchtop | Miniaturized | |||
NIRFlex N-500 | MicroNIR 1700 ES | Tellspec Enterprise Sensor | SCiO Sensor | |
Pretreatment | SG2 (29 SP) | SNV, SG2 (3 SP) | SNV, SG2 (25 SP) | SNV, SG2 (25 SP) |
R2 (Cal) | 0.99 | 1.00 | 0.54 | 1.00 |
R2 (CV) | 0.42 | 0.53 | 0.33 | 0.52 |
RMSEC [%] | 0.083 | 0.00015 | 0.579 | 0.00014 |
RMSECV [%] | 0.65 | 0.59 | 0.70 | 0.60 |
R2 (TSV) | 0.65 | 0.68 | 0.56 | 0.54 |
RMSEP [%] | 0.506 | 0.482 | 0.578 | 0.580 |
PLSR | ||||
---|---|---|---|---|
Benchtop | Miniaturized | |||
NIRFlex N-500 | MicroNIR 1700 ES | Tellspec Enterprise Sensor | SCiO Sensor | |
Pretreatment | SG (5 SP) | SG1 (7 SP) | SG1 (11 SP) | SG1 (11 SP) |
R2 (Cal) | 0.96 | 0.89 | 0.65 | 0.54 |
R2 (CV) | 0.88 | 0.80 | 0.52 | 0.46 |
RMSEC [%] | 0.182 | 0.286 | 0.505 | 0.581 |
RMSECV [%] | 0.309 | 0.382 | 0.591 | 0.630 |
R2 (TSV) | 0.94 | 0.62 | 0.55 | 0.55 |
RMSEP [%] | 0.210 | 0.525 | 0.571 | 0.568 |
GPR | ||||
Benchtop | Miniaturized | |||
NIRFlex N-500 | MicroNIR 1700 ES | Tellspec Enterprise Sensor | SCiO Sensor | |
Pretreatment | SG (5 SP) | SG1 (7 SP) | SG1 (11 SP) | SG1 (11 SP) |
R2 (Cal) | 1 | 0.99 | 0.99 | 0.99 |
R2 (CV) | 0.87 | 0.99 | 0.84 | 0.93 |
RMSEC [%] | 0.0011 | 0.0006 | 0.0002 | 0.0003 |
RMSECV [%] | 0.3150 | 0.0782 | 0.3397 | 0.2248 |
R2 (TSV) | 0.91 | 0.94 | 0.87 | 0.84 |
RMSEP [%] | 0.266 | 0.230 | 0.326 | 0.338 |
Intact | Milled | |||
---|---|---|---|---|
PLSR | GPR | PLSR | GPR | |
Pretreatment | SNV, SG2 (25 SP) | SNV, SG2 (25 SP) | SG1 (11 SP) | SG1 (11 SP) |
R2 (Cal) | 0.41 | 0.9 | 0.53 | 0.99 |
R2 (CV) | 0.28 | 0.55 | 0.48 | 0.9 |
RMSEC [%] | 0.654 | 0.272 | 0.580 | 0.0002 |
RMSECV [%] | 0.723 | 0.574 | 0.620 | 0.263 |
R2 (TSV) | 0.38 | 0.64 | 0.51 | 0.89 |
RMSEP [%] | 0.671 | 0.517 | 0.596 | 0.295 |
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Beć, K.B.; Grabska, J.; Plewka, N.; Huck, C.W. Insect Protein Content Analysis in Handcrafted Fitness Bars by NIR Spectroscopy. Gaussian Process Regression and Data Fusion for Performance Enhancement of Miniaturized Cost-Effective Consumer-Grade Sensors. Molecules 2021, 26, 6390. https://doi.org/10.3390/molecules26216390
Beć KB, Grabska J, Plewka N, Huck CW. Insect Protein Content Analysis in Handcrafted Fitness Bars by NIR Spectroscopy. Gaussian Process Regression and Data Fusion for Performance Enhancement of Miniaturized Cost-Effective Consumer-Grade Sensors. Molecules. 2021; 26(21):6390. https://doi.org/10.3390/molecules26216390
Chicago/Turabian StyleBeć, Krzysztof B., Justyna Grabska, Nicole Plewka, and Christian W. Huck. 2021. "Insect Protein Content Analysis in Handcrafted Fitness Bars by NIR Spectroscopy. Gaussian Process Regression and Data Fusion for Performance Enhancement of Miniaturized Cost-Effective Consumer-Grade Sensors" Molecules 26, no. 21: 6390. https://doi.org/10.3390/molecules26216390