The ppt gives basic idea about the freshness indicators which measure and communicate the quality of food.

1. FRESHNESS INDICATORS
in
FOOD PACKAGING
Presentaion By
B.L.Prasanna
PG/FT/0088118

2. INTRODUCTION
Consumers are more and more looking for
"freshness" but this property is not
guaranteed enough by directions required by
the law, such as the "best before date" or the
"use by date“.
The loss of quality of foods is related to a
combination of processes of different nature,
specific for each product that can be
chemical, biochemical, physical, or physico-
chemical

3. Chemical Reactions and Physical Processes Altering Food Quality
CHEMICAL AND
BIOCHEMICAL REACTIONS
PHYSICAL OR PHYSICAL-
CHEMICAL PROCESSES
Non enzymatic browning
Enzymatic browning
Hydrolisis of lipids
Oxidation of lipids
Hydrolisis of proteins
Denaturation of proteins
Aggregation of proteins
Hydrolysis of polysaccharides
Glycolysis
Polysaccharides synthesis
Discoloration of natural
pigments
Inactivation of vitamins
Changes in bio-availability of
vitamins and minerals
Recrystallization of sugars
Starch retrogradation
Loss of aroma
Sorption/Desorption of water
Loss of compartmentalization

4. What is Freshness indicator?
Measures the quality - life cycle.
Spoilage Or lack of freshness.
Communicate the quality
The freshness depends - 2 factors:-
Degree of freshness
Lack of spoilage

5. Freshness Indicator Functions
Monitor – quality
Track -through the critical points in
the supply chain.
Check the condition - anywhere along
the supply chain.
Measure directly the level of
(microbiological) contamination
Reduce - consumer complaints.

7. SPOILAGEMECHANISM
TIME
TEMPERATURE
INDICATOR
LEAK
INDICATOR
TEMP.
ABUSE
NON
INTEGRIT
Y OF
PACKAGE
MICROBIAL
GROWTH
MICROBIAL
CONTAMIN
ATION
MICROBI
OLOGICL
SPOILAG
E
FRESHNESS
INDICATOR

8. DEVOLOPMENT –
FRESHNESS INDICATORS!
We require the knowledge on
• Quality indicating metabolites in the
food already present
Metabolites produced by the micro-
organism
Concentration of the metabolites

9. Compounds IndicatingThe Quality PackedFood Product
GLUCOSE (glucose gradient)
ORGANIC ACIDS (L-lactic to D, in case meat)
ETHANOL (eth conc.-viable count of microbes-
fish)
VOLATILE NITROGEN COMPOUNDS
(trimethylamine, ammonia-fish)
BIOGENIC AMINES( putrecine & histamine in
fish–hygiene indicator to an extent)
CARBON DIOXIDE
ATP Degradation Compounds (K-value)
H2S AND SULPHURIC COMPOUNDS( spoilage of
poultry by Psedo..,Altromonas, results these..)
Ferm
entati
on

10. There are mainly 2 types of freshness indicators
Visible indicators - distinguishable and
interpretable by consumers, "quality labels" -
guarantee premium quality
Invisible indicators- Invisible to the
consumer, integrate a (RFID) tag that can be
read automatically at a distance, both during
distribution and in retail stores.
TYPES OF FRESHNESS INDICATORS

11. Visible Freshness indicators

12. “Freshness” indicator labels

13. Indicators sensitive to pH change
Change colour - presence of
volatile compounds
Direct determination of CO2 – pH
dye (eg.Fuchsine acid)
Use of the pH-dye bromothymol
blue -indicator - formation of CO2
- microbial growth

14. • Increase in CO2 - determine by microbial
contamination - CO2-sensitive packaging
indicator
• Ripeness of traditional fermented
vegetable foods
• Most frequently used pH-dye bromothymol
blue, many other reagents e.g. xylenol blue,
bromocresol purple, bromocresol green,
cresol red, phenol red, methyl red and
alizarin
Contd…

15. RipeSense(r) indicator
currently being trialled in New
Zealand and the USA.
Triggered by the aroma
components excreted by the
fruits.

16. Label indicator of fruit maturation level

17. Indicators sensitive to volatile nitrogen compounds
A plastic chip incorporating a
reagent-containing wick.
Label - attached to the package the
sharp barb on the back - penetrated
- enables contact between the
package headspace gases and the
reagent.
As volatile amines passed - a bright
pink colour - along the wick.

18. Fresh Tag

19. Indicators sensitive to hydrogen sulphide
Colour change of myoglobin by
hydrogen sulphide (H2S) - during the
ageing - packaged poultry.
Commercially - prepared myoglobin
dissolved in a sodium phosphate buffer
on small squares of agarose.

20. Fresh-Q
Freshness of packaged meat.
FreshQ, is a stick-on freshness sensor - outside of
fresh wrapped meat and poultry packages.
Detect food-borne bacteriological levels right
through the wrap.
A tangerine orange color - fresh.
When the bacteria count se’s to a critical level
ORANGE -> GRAY

21. Fresh-Q label

22. Nano sensors
Nanolayer of silver reacts with
hydrogen sulphide and forms
silver sulphide
A visually detectable colour
change from opaque light brown
to transparent

23. Indicators sensitive to miscellaneous microbial metabolites
Detecting the unacceptability -Respiring
products by measuring ethanol - headspace
with the aid of alcohol oxidase,
peroxidase and a chromogenic substrate.
Diacetyl is a volatile compound evolving from
meat as spoilage takes place
A diamine dye-based sensor system -
presence of diacetyl vapour.
Diacetyl migrating through the packaging
material would react with the dye and induce
a colour change.

24. Timestrip® smart labels
Timestrip® is more accurate than human
assumptions
Some Potential use’s
Useful for food items at high risk to bacteria
growth
Monitor freshness
Track food freshness in transit and storage
They can be applied to food items where there is a
high risk of bacteria
They are easy to apply and use

25. Applications
Fresh fish & Meat
Fruit and vegetables – monitor freshness
and help with the first in-first out principle
Poultry – bacteria can be found on raw or
undercooked chicken that multiplies rapidly
at temperatures between 40 °F and 140 °F
(can occur out of refrigeration and before
thorough cooking occurs)
Condiments - e.g. mayonaisse, salad cream,
chutney, mustard, tomato sauce or brown
sauce all have use within dates while a
dynamic date can ensure these are used at
their best and reduce waste

26. Pathogen indicators
Commercially - Toxin GuardTM
polyethylene-based packaging material - able to
detect the presence of pathogenic bacteria is in
contact with the material
Bound first to a specific, labelled antibody and
then to a capturing antibody printed as a certain
pattern
Detection of pesticide residues or proteins
resulting from genetic modifications.
Detection of specific microorganisms like
Salmonella sp., Listeria sp. and E. coli is Food
Sentinel SystemTM.

27. Toxin indicators
Toxin Indicators detect microbial growth
or toxins produced by pathogenic
microorganisms

28. ToxinGuard

29. Cont…
Based on immunochemical reaction, the
reaction taking place in a bar code.
If the particular microorganism is present
the bar code is converted unreadable.
Composed of cross-polymerised
polydiacetylene molecules and has a deep
blue colour.
The toxin binds - polydiacetylene film, the
colour of the film changes from blue to red.

30. Contamination detection
Placing antibody-based tests on polymer
packaging films to detect pathogens or other
selected micro organisms.
The insert sends a visual alert when it
encounters targeted spoilage bacteria, or
pathogens such as E-coli, Listeria and
Salmonella.
It will also alert consumers if chemicals such
as those used for pesticides are present in a
food.

31. Freshness indicators
Label is
transparent:
product is fresh
Label is red & bar
code is veiled
product is spoiled

32. Invisible Freshness indicator

33. RFID
Wireless monitoring of food packages
through tags, readers, and computer
systems.
RFID systems provide safety and
security benefits by tracking the
origin of food supplies.
Computer
Reader
RFID
tag

34. RFID
Advantages
- Better logistics for
retailers
– Better product info
– Improved shopping
experience
– Safety, traceability
Disadvantages
– Cost
– Technology not yet
mature
– Physical limitations
– No industrystandard

35. What is Biosensors?
Compact analytical devices that
detect, record and transmit
information pertaining to
biological reactions

36. Why Biosensors?
Bioreceptor specific to a target analyte
(enzymes, antigens, microbes, hormones etc.)
Transducer to convert biological signals to an
electrical response (electrochemical, optical
etc
Specificity
Speed/Response time
Simplicity
Continuous Monitoring
Preciseness

37. Few commercially available systems,
Contaminating bacteria
render bar-code
unreadable

38. Applications in the field
of food technology
Amprometric biosensor for polyphenolic
flavoring compounds in red wines.
Electrochemical biosensor –contaminants &
flavoring compounds in the food product.
Amp. Hypoxanthine bio…fish & meat tissue
off odors
In wine industry, these sensors are being
developed to analyze the sugar to alcohol
ratio in grapes and specific flavor from the
wine

39. ELECTRONIC NOSES
Electronic nose is a analytical tool
composed of array of sensors i.e. metal
oxide or polymer.
Capable of responding to volatile compounds
with changes in there electrical properties.
In this single compound is not analyzed but
samples are classified as acceptable or
unacceptable.

40. MECHANISM-ELECTRONICNOSE
SAMPLE/ VAP
Control
ler &
algorit
hm
with in
(compu
ter)
SENSOR -
1
SENSOR-
2
SENSOR-
3
SENSOR-
4
V
A
P
RESPONSE DATA
RESPONSE
SIGNALS
RESPONSE DATA
RESPONSE
SIGNALS
TR
AN
SD
UC
ER
MEA
SURE
ABLE
SIGN
AL

41. SensorfreshQ™
Easily confirms the
freshness of uncooked
meat or poultry
Revolutionary,
affordable, portable,
handheld electronic
“nose”.
Quickly measure the
bacteriological activity
in uncooked meat or
poultry.
(< 1 min.)

42. Procedure
In 3 simple steps,
1. Hold and select the meat
setting or poultry setting
2. Hold and press the
button
• A built-in fan draws in
the sample atmosphere
passed through four
electronic sensors that
measure by-products
of food-borne bacteria
3. Again, Hold and press the
button one more time

43. Result
GREEN LIGHT - fresh
YELLOW - ok but eat within 2 days
RED - freshness - no longer assured
Uses complex algorithms to determine the
freshness level

44. APPLICATION OF E- NOSES
Flavors
Aroma
Chemically volatile compounds
Any complex mixture of volatile compounds
Application to dairy products:-
- Ageing of milk & self life prediction.
- classification of bacteria culture in the
milk culture
- Determined the rind taste & ripening in
the cheese

45. Disadvantages of
Freshness indicator
Based in broad-spectrum color
changes
Target metabolites do not
necessarily indicate ,poor quality

46. Future prospects
Although research is ongoing in the area
of intelligent packaging, the application of
these systems in Europe has been limited
to a few time-temperature indicators.
In addition to information on product
identification, date of manufacture,
price, etc., new electronic and optical tags
could also function as combined time-
temperature, leak and/or freshness
indicators

47. The challenge is to develop an effective
sensor that is reliably sensitive to the
quality/safety level of a specific food type.
Different food quality indicators are being
studied by TNO Nutrition and Food
Research

48. Conclusions
Freshness indicators ,Bio-sensors,
Electronic noses, Toxin guards (Pathogenic
indicators)and other selective indicators are used
to detect a number of analyts in food technology
as glucose, alcohol ,amino-acids, proteins,
bacteria, antioxidants activity ,pH & temperature
monitoring etc.
Today ,Food industries using these
indicators & biosensors but in limited quantities
due to high cost ,denaturation problem ,due to bio
based material used for there fabrication, We
need knowledge of different sciences for its
production & better fabrication and even cost
effectiveness2

49. THANK YOU

53. Roast chickent Monoprix benefits fromFresh-Checkindicators from
Temptime Corp