deals with application of modern tools to detect quality control

1. Credit seminar -2
Meat quality assessment using
biophysical methods
Major advisor
Dr. B.B. Nayak,
Principal Scientist
Post Harvest Technology, CIFE,
Mumbai .
Presented by
Naresh Kumar Mehta
(PHT-PA01-04)
Ph.D. (Batch: 2011-14),
Post Harvest Technology
CIFE, Mumbai .

2. Introduction
• Factor influencing the meat properties are related to
breed, age and sex.
• Meat toughness depends mainly on MFP and
conjunctive tissue.
• MFP structure influenced by zoo-technical conditions.
‘Greenwood et al., 2007 and Gondret et al., 2005 studied
on myofibril types the lamb in and out door rearing.’

3. • Biophysical methods to measure meat component
properties directly or calculate them indirectly by using
obvious correlations.
• These techniques function on the basis three important
traits of food i.e. texture, appearance and nutritional
aspects
• Water content ≈ physical properties because it is
connected with juiciness and with pale, soft and
exsudative (PSE) and dark firm dry (DFD) defects.
• These defects are more precisely related to water
holding capacity (WHC).

4. Why does need arise?
• Chemical indices- time consuming
• Sensory indices - perceptional
• To obtain reliable information on meat quality throughout
the production process
• To reduce cumbersome data handling
• To be fast, accurate and non invasive techniques for
predicting technological and sensory qualities.
• Majority existing techniques are invasive

5. Biophysical methods
Mechanical methods,
Optical methods,
X-ray measurements
Nuclear magnetic resonance (NMR)
measurements

9. 1. Mechanical methods
• Instrumental methods –
• TA measurements(Compression, piercing)
• Rheometry (shearing)
• Ultrasound methods- analyzing the acoustic parameters of
wave propagating makes it possible to assess the
characteristic of the propagating medium and to characterize
it.
Monin (1998) reported that ultrasonic measurements give a
good prediction of meat texture on live animals and whole
carcass, while at the same time being inexpensive and non-invasive.

10. 2.Optical methods
a. Spectroscopic methods
I. Infrared spectroscopy
II. Raman spectroscopy
III. Visible spectroscopy and colorimetry
IV. Fluorescence spectroscopy
b. Imaging
I. Microscopic imaging
II. Optical microscopy
III. Histology
IV. Confocal laser scanning microscopy
V. Electron microscopy
VI. Scanning electron microscopy
VII. Transmission electron microscopy
VIII. Macroscopic imaging

11. I. Infrared spectroscopy
• Principle-Infrared spectroscopy (800-2500nm) is based on the
principle that the chemical bonds in organic molecules absorb or
emit infrared light when their vibrational state changes.
• Uddin et al.,2005 used for fresh and thawed fish to control of
fraudulent freezing-thawing cycle.

12. Tehnologija mesa 51 (2010) 2, 133–142

14. ii. Raman spectroscopy
• Raman spectroscopy is also a vibrational spectroscopic technique
used in condensed matter physics, biomedical applications and
chemistry to study vibrational, rotational, and other low-frequency
modes in a system.
• It relies on inelastic scattering of monochromatic light, usually from
a laser in the visible, IR, or near-UV spectra. It gives similar but
complementary information to IR spectroscopy.

15. iii.Visible spectroscopy and colorimetry
• It covers the visible spectra and the CIE
L*a*b*colour space as objective and non-destructive
tools for tissue characterization.
• Fish muscle absorbs different components
of light differently, depending on the
composition and state of the muscles.
• spectra change depending on the degree of
spoilage during chilled or frozen storage.
• Early detection of pale, soft and exsudative
(PSE) meat is a major potential application
of visible spectroscopy and colorimetry for
both pork and poultry meat

16. Figure 10A is showing a colour picture of the fillet composed of three colours - red (641
nm), green (552 nm) and blue (458 nm). This is a colour composition that is close to
what we actually can see with our eyes.
Figure 10B, is focusing on oxy- and deoxyhaemoglobin (572 nm) and blood is visualised
as dark spots.
Figure 10C, is focusing on methaemoglobin (630 nm) and blood is visualised as luminous
spots.

17. iv. Fluorescence spectroscopy
• is a type of electromagnetic spectroscopy which analyzes
fluorescence from a sample.
• For a well ordered biological tissue, fluorescence is
anisotropic and this anisotropy tends to disappear with
structural degradation.
• De-structuring processes like ageing, grounding or heating
have been successfully investigated.
• Tryptophan is an important intrinsic fluorescent probe that can
be used to assess the nature of the tryptophan
microenvironment.
• Proteins that lack tryptophan can be attached to an extrinsic
fluorophore probe.

18. 2.i Imaging
Microscopic imaging
Optical microscopy-
• Optical microscopy offers the simplest way to obtain
magnified images of biological tissues.
• This field covers a large range of techniques that have been
used for years to characterize meat and meat product
structures.
• Techniques can be classed simply depending on whether
samples must be prepared in thin cuts or not.
• Detection of A and I band.

19. ii.Histology
• Histology is a widely used as a tool for controlling meat
texture in food science.
• The technique may or may not require tissue staining with
specific dyes.
• Histology always needs very thin sample cuts.
• Fiber disorganization, fiber misalignment and increase in
fibers spacing have been analyzed.

21. iii.Confocal laser scanning microscopy
• is a fluorescence technique for obtaining high-longitudinal
resolution optical images.
• Evolution of the more traditional fluorescence microscopy.
• Key feature being the ability to produce point-by-point in-focus
images of thick specimens.
• Allowing 3D reconstructions of complex tissues.
• Because this technique depends on fluorescence, samples
usually need to be treated with fluorescent dyes to make
objects.
• visible, but contrary to the histological techniques, there is
no need for thin cuts

22. iv. Scanning electron microscopy (SEM)
• SEM gives images with great depth-of-field yielding a
characteristic 3D display that provides greater insight into the
surface structure of a biological sample
• Cryofixation, dehydration, embedding and staining

23. Fig. 6. SEM (200) images showing transverse section of raw and cooked muscle after heating at
121.1 1C for different time periods. The horizontal dotted bars indicate 150 mm. A, C, E: raw,
20 and 120 min cooked salmon muscle; B, D, F: raw, 20 and 120 min cooked chicken muscle

24. v. Transmission electron microscopy (TEM)
• In TEM electrons are passed through the sample.
• Resolution is higher than in SEM and the sample can be stained
with heavy metals to improve image quality

26. vi. X-ray measurements
• X-rays have long been used in medicine and others areas.
• principle is to obtain a measurement of the attenuation of the
penetrating energy.
• Different materials have different attenuation properties, and so
depending on the level of penetrating energy.
• possible to obtain quantitative measurements, in particular for
bone, lean meat and fat.
• Multiple technology tools using X-ray beams at different energy
levels have been developed, making it possible to discriminate fat,
bone and lean meat according to the energy attenuation
measured.

27. vii.Nuclear magnetic resonance
• NMR measurement of water proton relaxation times gives
information on the dynamics of water.
• Based on Water content and water mobility samples are
differentiated
• Significant correlations have been proposed between
measured vale and relaxation time for meat quality
parameters such as pH WHC or losses to cooking.
• The high costs involved do make it currently difficult to
consider installing NMR systems on production lines.

28. conclusion
• All the results presented here point out the wealth of potential
for using biophysical methods in meat quality investigations.
• The field of research is vast, and meat scientists still have years
of exciting work ahead before offering to meat industry a
cheap, robust, reliable, portable, rapid, universal and
magnificent meat quality sensor.

29. Thank
you