Apparatus and method for measuring and correlating characteristics of fruit with visible/near infra-red spectrum

• US 6,512,577 B1
• Filed: 03/13/2000
• Issued: 01/28/2003
• Est. Priority Date: 03/13/2000
• Status: Expired due to Fees

• Current Assignee: Autoline, Inc., Aweta Holding, B.V., FPS Food Processing Systems BV (Thyssen Bornemisza Family)
• Original Assignee: FPS Food Processing Systems BV (Thyssen Bornemisza Family)
• Inventors: Ozanich, Richard M.
• Primary Examiner(s): Evans, F. L.
• Application Number:
  US09/524,329
• Time in Patent Office: 1,051 Days
• Field of Search: 356/73, 356/326, 356/328, 356/402, 250/910, 209/588
• US Class Current: 356/73
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0224 using polarising or depolarising elements
• CPC Class Codes: G01J 3/28 Investigating the spectrum using colour filters G01J3/51
• CPC Class Codes: G01J 3/36 Investigating two or more bands of a spectrum by separate detectors
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01J 3/501 Colorimeters using spectrally-selective light sources, e.g. LEDs
• CPC Class Codes: G01J 3/51 using colour filters
• CPC Class Codes: G01J 3/513 having fixed filter-detector pairs
• CPC Class Codes: G01J 3/524 Calibration of colorimeters
• CPC Class Codes: G01N 2021/3155 Measuring in two spectral ranges, e.g. UV and visible
• CPC Class Codes: G01N 2021/8466 Investigation of vegetal material, e.g. leaves, plants, fruits
• CPC Class Codes: G01N 21/3563 for analysing solids; Preparation of samples therefor
• CPC Class Codes: G01N 21/359 using near infrared light
• CPC Class Codes: G01N 2201/129 Using chemometrical methods
• CPC Class Codes: G01N 33/025 Fruits or vegetables
• CPC Class Codes: Y10S 250/91 Food sample analysis using invisible radiant energy source

Abstract

This disclosure is of 1) the utilization of the spectrum from 250 nm to 1150 nm for measurement or prediction of one or more parameters, e.g., brix, firmness, acidity, density, pH, color and external and internal defects and disorders including, for example, surface and subsurface bruises, scarring, sun scald, punctures, in N—H, C—H and O—H samples including fruit; 2) an apparatus and method of detecting emitted light from samples exposed to the above spectrum in at least one spectrum range and, in the preferred embodiment, in at least two spectrum ranges of 250 to 499 nm and 500 nm to 1150 nm; 3) the use of the chlorophyl band, peaking at 680 nm, in combination with the spectrum from 700 nm and above to predict one or more of the above parameters; 4) the use of the visible pigment region, including xanthophyll, from approximately 250 nm to 499 nm and anthocyanin from approximately 500 to 550 nm, in combination with the chlorophyl band and the spectrum from 700 nm and above to predict the all of the above parameters.

Claims

1. A method of determining characteristics of samples comprising:

A building algorithms of the relationship between sample characteristics and absorbed and scattered light from a sample having an interior;

B illuminating the interior of a sample with a broadband frequency spectrum;

C detecting the spectrum of absorbed and scattered light from the sample;

D analyzing the detected spectrum of absorbed and scattered light from the sample with the algorithms;

calculating the characteristics of the sample.

2. The method of claim 1 further comprising:

A building the algorithms to generate a regression vector that relates the frequency spectrum, further comprised of VIS and NIR spectra, to brix, firmness, acidity, density, pH, color and external and internal defects and disorders;

B storing the regression vector, in a CPU having a memory, as a prediction or classification calibration algorithm;

C illuminating the sample interior with a spectrum of 250 to 1150 nm;

D inputting the detected spectrum of absorbed and scattered light from the sample interior to a spectrometer;

E converting the detected spectrum from analog to digital and inputting the converted spectrum to a CPU;

combining the spectrum detected;

F comparing the combined spectrum with a stored calibration algorithm;

G predicting the characteristics of the sample.

3. The method of claim 1 further comprising:

A the characteristics are chemical characteristics including acidity, pH and sugar content.

4. The method of claim 1 further comprising:

A the characteristics are physical characteristics including firmness, density, color, appearance and internal and external defects and disorders.

5. The method of claim 1 further comprising:

A the characteristics are consumer characteristics.

6. The method of claim 1 further comprising:

A sampling is of samples from the group of C—

H, N—

H or O—

H chemical groups;

B illuminating of the interior of the sample is with a frequency spectrum including visible and near infrared light;

C building algorithms for a correlation analysis separately of Brix, firmness, ph and acidity in relation to the light spectrum output from the illuminated sample;

D detecting the spectrum of absorbed and scattered light from the sample with a light detector.

7. The method of claim 2 further comprising:

A illuminating of the interior of the sample with a frequency spectrum of 250 to 1150 nm;

B detecting the spectrum with a light detector fiber;

shielding the light detector fiber from the illuminating spectrum;

C measuring the spectrum for chlorophyl at around 680 nm;

D correlating the characteristics of Brix, firmness, pH and acidity with the measured spectrum.

8. An apparatus for determining characteristics of samples comprising;

A at least one broadband light source;

a sample having an sample surface and an interior;

input mechanism of positioning the at least one light source proximal the sample surface;

B at least one light detector;

output mechanism of positioning the at least one light detector proximal the sample surface;

C at least one mechanism of measuring the illumination detected from the sample;

D the at least one light source produces a spectrum within the range of 250 to 1150 nm;

E the at least one mechanism of measuring the illumination is a spectrometer;

the spectrometer has at least one input;

F the at least one light detector is a light pickup fiber;

the at least one light detector collects a spectrum which is received by the at least one spectrometer input;

G the sample is from the chemical group consisting of C—

H, N—

O, and O—

H.

9. The apparatus of claim 8 further comprising:

A the least one light source is a tungsten halogen lamp;

the illumination is transmitted to the sample surface by fiber optics;

B the at least one light detector is a fiber optics light pickup;

C the at least one spectrometer comprises a 1026 linear array detector.

10. The apparatus of claim 8 further comprising:

A the at least one light source is an illumination fiber.

11. The apparatus of claim 8 further comprising:

A the at least one light source comprises a plurality of illumination fibers;

B the plurality of illumination fibers are arrayed such that each illumination fiber is equidistant from adjoining illumination fibers;

the at least one light detector is positioned centrally in the array of illumination fibers.

12. The apparatus of claim 11 further comprising:

A the plurality of illumination fibers are comprised of 32 illumination fibers.

13. The apparatus of claim 8 further comprising:

A the light source is a 5 w tungsten halogen lamp.

14. The apparatus of claim 8 further comprising:

A the at least one light source comprises a plurality of light sources which is further comprised of two 50 w light sources;

B the at least one light detector is comprised of a plurality of light detectors.

15. The apparatus of claim 14 further comprising:

A the plurality of light detectors are arrayed such that each light detector is equidistant from adjoining light detectors.

16. The apparatus of claim 15 further comprising:

A the plurality of light detectors comprise twenty-two light detectors.

17. The apparatus of claim 9 further comprising:

A the light source comprised of an ellipsoidal reflector with a 50 w bulb with cooling fan;

the fiber optics is comprised of at least one fiber optic fiber for transmission of the light source to the sample surface.

B the at least one fiber optic and the at least one light detector spring biased against the sample surface;

the pressure exerted by the spring biasing limited by the character of the sample.

18. The apparatus of claim 8 further comprising:

A the at least one light source is a 5 w tungsten halogen lamp;

the at least one light detector is a single fiber optic fiber;

the illumination source is positioned against the sample surface 180 degrees distal to the detection fiber.

19. The apparatus of claim 11 further comprising:

A a polarization filter is positioned between the at least one light source and the sample;

B a matching polarization filter is positioned between the at least one light detector and the sample.

20. The apparatus of claim 19 further comprising:

A the polarization filter is a linear polarization filter;

the matching polarization filter is a linear polarization filter rotated 90 degrees in relation to the polarization filter.