Applications of Spectroscopy techniques like FTIR and NIR (Fourier Transform Spectroscopy) and (Near Infarred Spectroscopy)

1. PRESENTED BY
DEBOMITRA DEY
RA 1512022010004
18.08.15
Image Source: Internet

2.  WHAT IS FTIR?
 FTIR ANALYSIS
 APPLICATIONS IN FOOD
(QUANTITATIVE AND QUALITATIVE ANALYSIS)
 WHAT IS AT-FTIR?
 WHAT IS NIR?
 NIR APPLICATIONS IN FOOD
OUTLINE:
1. QUALITATIVE (FTIR)
2. QUANTITATIVE (AT-FTIR)

3. WHAT IS FTIR?
 It is the technique used to obtain spectrum of absorption,
emission
 The main aim is to measure the amount of light absorbed by a
sample at each wavelength
 FTIR has application both in Qualitative and Quantitative
Analysis
 It is a non-destructive, time saving method, can detect range of
functional groups and is sensitive to change in molecular
structure (Amir et al. 2013).

4. SOME CHARACTERISTIC INFRARED ABSORPTION PEAKS
Source: Skoog

5. WHAT IS FTIR? CONTD.
 Infrared spectroscopy is a powerful spectroscopy technique
and can utilized for both quantitative and qualitative
analysis, as the output received is a detailed information
about the chemical composition of the substance in the IR
spectrum (Sedman et al).
 FTIR spectroscopy is an appealing technology for the food
industry because simple, rapid, and non-destructive
measurements of chemical and physical components
can be obtained (Saona et al. 2011).
 Advances in FTIR instrumentation combined with the
development of powerful multivariate data analysis methods
make this technology ideal for large volume, rapid screening
and characterization of minor food components down to
parts per billion (ppb) levels (Saona et al. 2011)

6. COMMON APPLICATIONS OF FTIR IN FOOD
 Infrared Milk Analyser, to determine Fat, Protein, Lactose
content.
 Measurement of degree of unsaturation of fats and oils.
 Identification of flavour and aroma, FTIR in combination with
GC. Can be used to analyse and evaluate essential
components from cinnamon barks.
 For packaging film- to identify structural changes occurred
due to exfoliation or intercalation of layered silicates in
polymer matrix.

7. 1. QUALITATIVE ANALYSIS
Two applications:
1. FTIR in identification of wheat varieties.
2. FTIR for spectroscopy of Edible Oil.
APPLICATIONS OF FTIR

8.  Qualitative characteristic studies
 FTIR works on basis of functional group and provides
information in the form of peaks
 On the basis of the peak value of moisture, protein,
chemical, physical and rheological properties and
grain hardness by standard methods were
determined.

9.  FTIR provides information on the basis of chemical composition and
physical state of whole sample (Cocchi et al. 2004)
 Peaks for water were observed on 1,640 cm−1 and 3,300 cm−1
(Manley et al. 2002).
 FTIR is one of the most elusive methods for the analysis of moisture.
 Water absorbs strongly in the infrared region of the spectrum due to
its OH stretching and H bending vibrations however its quantization is
frequently complicated by spectral interferences from other OH
containing constituents such as alcohols, phenols and hydro
peroxides and confounded further by hydrogen bonding effects (Dong
et al. 2000).
 FTIR provides an excellent means to visualize the chemical
composition of different wheat varieties and it is very quick, reliable
and cheaper analytical technique which can effectively be used for
estimation of different wheat quality parameters. (Amir et al. 2013).

10.  Qualitative determination of organic compounds as characteristic
vibrational mode of each molecular group causes appearance of
bands in IR at specific frequency, further influenced by surrounding
functional groups (Vlachos et al. 2006)
 The application of FTIR in present study –
1. Determination of extra virgin olive oil adulteration with various
vegetable oil (sunflower oil, soya bean oil, sesame oil, corn oil)
2. Oxidation process monitoring of corn oil (QUANTITATIVE
ANALYSIS)

11. RESULT FOR ADULTERATION OF VIRGIN OLIVE OIL

12. For Oxidation:
Oil sample was heated with UV radiation
FTIR spectra was collected at different temperature
Results are collected and compared with peroxide value method
The band shift observed
at 3009 cm-1 assigned
to C-H stretching
vibration of cis-double
bond allow
determination of extra
virgin oil adulteration.

13.  Other applications of Qualitative analysis of FTIR are detection of
moisture content, fat, protein in milk products, lipid content in oils.
 FTIR spectra of bacteria are specific to a given strain and show the
spectral characteristics of cell components, such as fatty acids,
membrane and intracellular proteins, polysaccharides, and nucleic
acids (Dziba et al. 2007).
 Fourier transform infrared (FTIR) technology has substantial
potential as a quantitative quality control tool for the food industry.
FTIR analysis methods are convenient, rapid and automatable, and
in conjunction with attenuated total reflectance (ATR) technology,
dramatically simplify sample handling. The key elements of FTIR
spectroscopy are presented along with a selection of methods under
development, including analyses of milk, meats, fats and oils,
butter, sweetened condensed milk and juices. (Voort 1992).
FTIR APPLICATIONS (QUALITATIVE ANALYSIS)

14.  Difficulties in sample handling, limited exploitation of Infrared
Spectroscopy as an analytical technique in areas like food
analysis.
DISADVANTAGES OF USING FTIR
For Quantitative Analysis
FTIR is an excellent tool for quantitative analysis as intensity
of band is directly proportional to the concentration (Beer
Lambert’s Law)

15. WHAT IS AT-FTIR?
 Attenuated Total Reflectance – FTIR
 How does it work?
Optical principle unlike FTIR (Transmission)
 ATR technique provides one of the easiest and most convenient
ways of handling samples for Infrared spectroscopy
 ATR-FTIR can convert ATR spectra to Transmission spectra by
correcting wavelength dependence of effective path length, thus
making possible to compare ATR and Transmission spectra
 The versatility of ATR is its sampling technique i.e. HATR
(Horizontal Attenuated Total Reflectance). For e.g.. In food used for
minced meat, and solid chocolate.
 Replace constant path transmission cells, salt plates, KBr pellets
used in analysis liquid, semi-liquid and solids. (FTIR)

17. APPLICATIONS OF FTIR
2. QUANTITATIVE ANALYSIS
AT-FTIR
1)SUGAR ANALYSIS
2)FRUIT CONTAINING PRODUCTS
3)SWEETENED CONDENSED MILK
4)FATS AND OILS

18. 1.SUGAR ANALYSIS
 Based on bands in 1250-900 cm-1 region, which mainly
represents C-OH bending vibration.
 Sugars like Sucrose, Glucose and Fructose.
 Individual sugar has characteristic set of absorption in this
region, these bands are severely overlapped in the
spectrum of mixture of sugars.
 However, with the application of multi-variate analysis
techniques, quantitation of individual sugars in such
mixtures can be achieved.
 P-matrix method.

19. ATR-FTIR SPECTRA OF SUCROSE (A), GLUCOSE (B), FRUCTOSE (C)

20. 2. FRUIT CONTAINING PRODUCT
 Spectra for detection of adulteration in Fruit jams and Purees.
 The spectra of Jam was dominated by the presence of water.
 Spectra of Fruit Puree – the fruits were freeze thawed then
blended in the food mixer.
 Common adulteration observed- Sucrose, Apple Puree, Plum
Puree.
 Further the authors concluded that FTIR/ATR can be employed
for detection of adulterants in freeze dried instant coffee,
authentication of meats.

21. 3. SWEET CONDENSED MILK (SCM)
 Method developed by McGrill IR Group.
 Extensively used ingredient in manufacture of bakery products,
confectionery, etc.
 Composition of SCM 
 Highly viscous, caution while selecting the ATR accessory i.e. ATR
crystal.
 Spectral region above 1500cm-1 is dominated by water absorption
bands @ ~3400 and 1640 cm-1.
 Major spectral feature C-H stretching absorption @ 2927-2855 cm-1.
 Ester linkage carbonyl absorption of fat @ 1747 cm-1.
 Amide bands of protein and sugar absorption bands at
1250- 900 cm-1.
1. Milk fats  8.5-9.7%
2. Milk Solids  28.5-30%
3. Sugar  43.5- 44.8%

22. FTIR/ATR SPECTRUM
OF SCM
DIFFERENCE IN
SPECTRUM
OBTAINED BY
SCALED
SUBTRACTION OF
THE SPECTRUM OF
WATER
1- C-H STRETCHING ABSOPRTION, 2-ESTER CARBONYL ABSORPTION
3, 4- AMIDE BANDS OF PROTEINS, 5- CARBOHYDRATE ABSORPTIONS

23. 4. FATS AND OILS
 Analysis of fats and oils in determination of isolated trans isomers,
official method by AOCS (American Oil Chemists Society),
Association of Official Analytical Chemists (AOAC).
 Determination is based upon peak height of absorption band of
isolated trans bonds @ 966 cm-1, which is due to C=C-H bending
vibration.
 Further FTIR/ATR can used for monitoring oil oxidation.

24. WHAT IS NIR?
 NEAR INFRARED REFLECTANCE
SPECTROSCOPY
 Based on molecular overtone and vibration
 Molar absorptivity is quite small
 Depending on the same the spectra maybe
measured either in transmission or reflection

25. Image source: Internet
NIR SPECTROPHOTOMETER

26.  The major advantage of NIR is that usually no sample
preparation is necessary, hence the analysis is very
simple and very fast (between 15 and 90 s) and can be
carried out on-line.
 One of the strengths of NIR technology is that it allows
several constituents to be measured concurrently. In
addition, for each fundamental vibration there exists a
corresponding series of overtone and combination bands
with each successive overtone band approximately an
order of magnitude less intense than the preceding one.
 This provides a built-in dilution series which allows
several choices of absorptions of different intensity
containing the same chemical information. Finally, the
relatively weak absorption due to water enables high-
moisture foods to be analysed (Osborne, 2000).
ADVANTAGES OF NIR SPECTROSCOPY

27. APPLICATIONS OF NIR SPECTROSCOPY
1.To predict meat and meat products
 Predict the content of main chemical component i.e. crude protein (CP),
Intramuscular fat (IM), moisture/dry matter.
 Water is a variable component , almost 75% of total matter; specific
absorbance of O-H bonds @ 1450 and 1940 nm in NIR spectra.
 For the analysis of CP and IM specific absorbance @ 1460-1540 nm and
2000-2180nm respectively.
 NIR spectroscopy has considerable potential to predict simultaneously
several meat into quality classes.
 NIR is suitable alternative to analytical procedures which can be time
consuming expensive and sometimes hazardous to health and
environment (Prieto et al, 2009).

28.  Most NIR spectroscopy research on citrus fruit have focussed on internal
quality attributes (Lin et al, 2010, Gómez et al, 2006, Fraser et al, 2003).
 Molecular vibrations particularly by O-H and C-H bonds are responsible
for strong absorption bands in the NIR spectral region by biological
material, with the absorption band of O-H bonds dominating in hydrated
material (Golic et al 2003, Nicolaĭ et al 2009).
2. Internal and External Quality Analysis
of Citrus Fruit

29. REFERENCES
1. Amir Muhammad Rai, Anjum Muhammad Fquir, Khan Issa
Muhammad, Khan Rafiq Mozzam, Pasha Imran, Nadeem
Muhammad, Application of FTIR Spectroscopy for identification
of wheat varieties (2013), Journal of Food Science Technology,
50(5), pp: 1018-1023.
2. Brian G Osborne, Near Infrared Spectroscopy in Food Analysis,
(2006), John Wiley & Sons.
3. Magwaza S Lembe, Opara Umezuruike, Nieuwoudt Helene,
Cronje J R Paul, Saeys Wouter, Nicolai Bart, Near Infrared
Reflectance Spectroscopy Applications for Internal and External
Quality Analysis of Citrus Fruit- A Review, Food Bioprocess
Technology, (2011) Vol 5. Issue 2, pp: 425-444.

30. 4. Mossaba, Spectral Methods in Food Analysis, 1998
CRC Press, pp. 409-422.
5. Prieto N, Roehe R, Lavin P, Batten G, Andres S,
Application of NIR spectroscopy to predict meat & meat
products quality- A review (2009), Meat Science 83, pp:
175-186.
6. Vlachos N, Skopelitis Y, Psarondaki M,
Konstantinidon V, Chatzilazarou A, Tegou E, Applications
of Fourier Transform Infrared Spectroscopy to edible oils
(2006), Analytica Chimica Acta, 573-574, pp: 459-465.