Food Packaging Technology Multiple Choice Questions & Answers (MCQs) on “Intelligent Packaging Systems”.
1. Intelligent packing techniques can also serve as freshness indicators.
a) True
b) False
Answer: a
Clarification: The given statement is true. Intelligent packing can serve as freshness indicator. It can be divided into external and internal indicator on basis of their use. External indicators are those which are attached outside the package. E.g. Time-Temperature & Microbial growth Indicator. Internal indicators are those which are placed inside the package, either to the head space of the package or attached into the lid. Eg. Oxygen Indicators, Carbon dioxide Indicators, Microbial Growth Indicators, Pathogen Indicators.
2. Which of the following is a Time-Temperature Indicator (TTI)?
a) Life lines fresh check
b) Radiofrequency identification
c) Electronic nose
d) Ultrasonic indicator
Answer: a
Clarification: Line lines fresh check is a Time-Temperature Indicator (TTI). It is an external indicator, placed outside the food packet. It is generally used in food stored under chilled & frozen conditions. Lifelines’Fresh Check indicators are – color-changing, self-adhesive labels which respond to cumulative exposure to temperature.
3. Which of the following TTI is based on enzymatic lipase color change?
a) Electronic nose
b) 3M Monitor Mark
c) LifeLines Fresh-Check
d) Vitsab Single Dot Label (TTI)
Answer: d
Clarification: Vitsab Single Dot Label (TTI) is based on enzymatic lipase color change. It is based on the principle of enzymatic hydrolysis of a lipid substrate (e.g. tricaproin) causes acid release (e.g. caproic acid) & the pH drop is translated in a color change of pH indicator to dark yellow.
4. Which of the following TTI is based on dye diffusion?
a) Electronic nose
b) 3M Monitor Mark
c) LifeLines Fresh-Check
d) Vitsab Single Dot Label (TTI)
Answer: b
Clarification: 3M Monitor Mark is based on dye diffusion. A visco-elastic material migrates into a diffusely light reflective porous matrix at a temperature dependent rate. This causes a progressive change of the light transmissivity of the porous matrix & provides a visual response. Response of indicator is the blue dye ester diffusing along a wick. The useful range of temperature & response life of the TTI are determined by type of ester & the concentration at the origin.
5. Which of the following TTI is based on polymerization reaction?
a) 3M Monitor Mark
b) Electronic nose
c) Vitsab Single Dot Label (TTI)
d) LifeLines Fresh-Check
Answer: d
Clarification: LifeLines Fresh-Check is based on polymerization. It is based on the property of distributed di-acetylene crystals to polymerize through a lattice-controlled solid state reaction proceeding via 1,4 addition polymerization & resulting in high color polymer.
6. Which of the following is an optical chemical sensing method of freshness indication in intelligent packaging?
a) RFID
b) Electronic nose
c) Vitsab Single Dot Label (TTI)
d) 3M Monitor Mark
Answer: b
Clarification: Electronic nose is a simple optical chemical sensing method (colorimetric nose) that utilises the color change taking place in an array of metalloporphyrin dyes upon ligand binding. The liganding vapors (alcohols, amines, ethers, phospines, thiols, halocarbons & ketons) can be visually identified. It is an internal indicator.
7. RFID is used for intelligent packaging in storage and distribution.
a) True
b) False
Answer: a
Clarification: The given statement is true. RFID: Radio Frequency Identification is a non contact, wireless, data communication form where tags of some material, usually embedded with the IC chip, are programmed with unique information & attach to object for identification & tracking. As tagged items pass by readers, the data from the tags is decoded & transfer to the host computer for processing.
8. Carbon dioxide indicators are based on pH dyes.
a) True
b) False
Answer: b
Clarification: The given statement is false. Carbon dioxide indicators are based on chemicals. It gives information about storage conditions and package leak. It is most commonly used in modified or controlled atmosphere food packaging.
9. Which of the following is not an internal indicator?
a) Oxygen indicator
b) Pathogen indicator
c) Microbial growth indicator
d) Time-Temperature indicator
Answer: d
Clarification: Time-Temperature indicator is not an internal indicator. The principle/reagents used are- mechanical, chemical and enzymatic. It gives information about storage conditions. Its application is in food stored under chilled & frozen conditions.
10. Which of the following is based on immuno-chemical methods of freshness indicator?
a) Pathogen Indicators
b) Microbial growth indicator
c) Oxygen indicator
d) Carbon dioxide indicator
Answer: a
Clarification: Pathogen Indicators use various chemical & immuno-chemical methods reacting with toxins. It gives information about specific pathogenic bacteria such as Escherichia Coli O157. It is most commonly used in perishable foods such as meat, fish & poultry.
11. Microbial growth indicator is same as pathogenic indicator.
a) True
b) False
Answer: b
Clarification: The given statement is false. Microbial growth indicator is the one which indicates the first order kinetic growth of a spoilage microorganism. It uses pH dyes and all dyes reacting with certain metabolites (volatiles or non volatiles). Whereas, pathogenic indicator is the one which indicates the presence of toxins producing pathogenic microorganisms which may or may not cause spoilage, but can cause disease.