250+ TOP MCQs on Paper Making – 1 and Answers

Food Packaging Technology Multiple Choice Questions & Answers (MCQs) on “Paper Making – 1”.

1. __________ is the interface between the pulp mill and the papermaking process.
a) Stew preparation
b) Stock preparation
c) Dew preparation
d) Stall preparation
Answer: b
Clarification: Stock preparation is the interface between the pulp mill and the papermaking process in which pulp is treated mechanically and, in some instances, chemically by the use of additives and is thus made ready for forming into a sheet or board on the paper machine. During the stock preparation steps, the pulps are most conveniently handled as aqueous slurries.

2. The separation of all the fibers from one another and their dispersion in water is called ________
a) Slushing
b) Sheeting
c) Wetting
d) Mashing
Answer: a
Clarification: The separation of all the fibers from one another and their dispersion in water is called slushing or repulping. In the papermaking process utilizing purchased pulps and waste paper which are received as dry sheets, the first step is the separation of all the fibers from one another, and their dispersion in water with a minimum of mechanical work to avoid altering the fiber properties. This process is known as slushing or repulping and is carried out in a machine such as the hydrapulper, so called because of the hydraulic forces that are developed. When the pulping and papermaking operations are adjacent to one another, pulps are usually delivered to the paper mill in slush form directly from the pulping operation.

3. Stock (fibrous material) is prepared by which of the following processes?
a) Extraction and expelling
b) Beating and extraction
c) Extraction and refining
d) Beating and refining
Answer: d
Clarification: Stock—as fibrous material is commonly called—is prepared by two chief processes commonly referred to as beating and refining. Both operations are fundamentally the same; in many situations, the two terms are used synonymously. Beating and refining are used to improve the strength and other physical properties of the finished sheet, and to influence the behavior of the system during the sheet-forming and drying steps.

4. The object of beating is _________ of the fibers by assisting them to imbibe water.
a) To increase the surface area
b) To decrease the surface area
c) To increase the volume
d) To decrease the volume
Answer: a
Clarification: The object of beating is to increase the surface area of the fibers by assisting them to imbibe water. As a result, additional bonding opportunities are provided for between cellulose molecules of neighboring fibers.

5. After beating, the mixture of pulp is brought to a consistency of ______
a) 3%–5%.
b) 1%–7%.
c) 5%–7%.
d) 6%–9%.
Answer: c
Clarification: The mixture of pulp (known as the furnish) is passed into the beater and brought to a consistency of 5%–7%. The beating makes the fibers more flexible, causing them to become relatively mobile and to deform plastically on the paper machine.

6. An unbeaten pulp has a low density.
a) True
b) False
Answer: a
Clarification: The given statement is true. Because papermaking fibers are stiff and springy, the resulting paper would be flabby and weak if made into a sheet of paper without beating. There would be little adhesion between the fibers and they could not be consolidated under the presses of the paper machine. A sheet formed from an unbeaten pulp has a low density, and is rather soft and weak.

7. Extreme beating produces very dense, translucent, glassine-type sheets.
a) True
b) False
Answer: a
Clarification: The given statement is true. If the same unbeaten pulp is beaten, then the resultant paper is much more dense, hard and strong. If taken to the extreme, beating produces very dense, translucent, glassine-type sheets. Thus, beating can be controlled to produce paper types as widely different as blotting and greaseproof paper.

8. In many paper mills, beaters have been replaced by ________
a) Continuous refiners
b) Continuous disks
c) Continuous sheets
d) Continuous templates
Answer: a
Clarification: In many paper mills, beaters have been replaced by continuous refiners, such as disk refiners (where rotary disks rotate against a working surface) and conical refiners. However, the batch beater is a convenient vessel for adding chemicals and mixing them intimately with the pulp in order to give special properties to the final paper.

9. Which of the following is not a filler used in paper?
a) Titanium dioxide
b) Sodium hydroxide
c) Kaolin clay
d) Calcium carbonate
Answer: b
Clarification: Sodium hydroxide is not a filler used in paper. Calcium carbonate is the most important papermaking filler followed by kaolin clay, with limited use of titanium dioxide. Fillers can improve brightness, opacity, softness, smoothness and ink receptivity, and are essentially insoluble in water under the conditions of use. Filler particles are often 0.5 to 3 mm in diameter, which is much smaller than the fibers used in making paper. Hence, fillers help in making the paper smooth. Not only this, fillers also increase papers’ opacity and brightness as it increases light scattering efficiency.

10. Which of the following is used to increase water resistance of paper?
a) Filling
b) Sizing
c) Stretching
d) Sheeting
Answer: b
Clarification: Sizing is the process of adding materials to the paper in order to render the sheet more resistant to penetration by liquids, particularly water. Rosin is the most widely used sizing agent, but starches, glues, caseins, synthetic resins and cellulose derivatives are also used. The sizing agents may be added directly to the stock as beater additives to produce internal or engine sizing.

11. Resistance of paper against water is called wet-strength.
a) True
b) False
Answer: a
Clarification: The given statement is true. The required wet strength (up to 50% of the dry paper strength can be retained) is obtained with the aid of wet-strength additives that are capable of covalently bonding in order to preserve paper strength in the presence of water. Linerboard, carrier board, bleached carton and liquid paperboard are some of the principal grades that require an amount of wet strength to be functional.

250+ TOP MCQs on Aseptic Packaging and Answers

Food Packaging Technology Multiple Choice Questions & Answers (MCQs) on “Aseptic Packaging”.

1. Filling of sterile containers with commercially sterile product is known as __________
a) passive packaging
b) active packaging
c) intelligent packaging
d) aseptic packaging
Answer: d
Clarification: Filling of sterile containers with commercially sterile product is known as aseptic packaging. ‘Asepsis’ means exclusion or absence of any unwanted microorganism. Aseptic packaging is done-
i. to take advantage of HTST sterilization process.
ii. to enable containers to be used that are unsuitable for in-package sterilization
iii. to extend the shelf life of product at normal temperature by packaging them aseptically.

2. The sealing in aseptic packaging is known as __________
a) vacuum sealing
b) hermetic sealing
c) closed sealing
d) thermo sealing
Answer: b
Clarification: The sealing in aseptic packaging is known as hermetic sealing. Hermetic sealing is done to prevent recontamination of enclosed product.

3. Aseptic Packaging is also known as in-package sterilization.
a) True
b) False
Answer: b
Clarification: The given statement is false. In-package sterilization is the process in which the package is sterilized after filling. Whereas, in aseptic packaging sterilized product is filled in sterilized container in a controlled environment.

4. Which of the following steps is not included in aseptic packaging?
a) Sterilizing product before filling
b) Hermetic Sealing
c) Aseptic filling
d) Sterilizing product after filling
Answer: d
Clarification: Sterilizing product after filling is not included in aseptic filling. Aseptic packaging contains the following steps –
i) Sterilizing product before filling
ii) Simultaneous sterilizing package before filling
iii) Filling in aseptic environment
iv) Hermetic sealing.

5. The first aseptic packaging of food was carried out in ________
a) 1913
b) 1926
c) 1950
d) 1974
Answer: a
Clarification: The first aseptic packaging of food was carried out in 1913. Nielsen from Denmark aseptically packaged milk in metal cans.

6. ___________ process is used in aseptic packaging.
a) Autoclaving
b) Sterilization
c) Disinfection
d) Heating
Answer: b
Clarification: Sterilization process is used in aseptic packaging. Sterilization is the process of removal or destruction of all microbial life. There are three common sterilization processes –LTLT, HTST and UHT.

7. LTLT is used in Aseptic Packaging.
a) True
b) False
Answer: b
Clarification: The given statement is false. LTLT stands for Low Temperature Long Time Sterilization. LTLT process includes heating the product at low temperature for a longer time (LTLT – 63.15°C, 30 minute). This long time process makes it very slow. Therefore it is not used in aseptic packaging.

8. UHT is used in Aseptic Packaging.
a) True
b) False
Answer: a
Clarification: The given statement is true. UHT stands for Ultra High Temperature. UHT process includes heating the product at ultra high temperature for a very short span of time (UHT – 75°C to 140°C, less than 5 seconds). This process is very efficient due to the short time it consumes. Therefore, it is very favorably used in aseptic packaging.

9. HTST is used in Aseptic Packaging.
a) True
b) False
Answer: a
Clarification: The given statement is true. HTST stands for High Temperature Short Time. HTST process includes heating the product at high temperature for a short time (HTST – 72° C, 15 minutes).

10. Sterilization using irradiation is done by ________
a) Non-ionizing radiation
b) Ionizing radiation
c) Chemical Treatment
d) Thermal Treatment
Answer: a
Clarification: Sterilization using irradiation is done by ionizing radiation. Irradiation is done by one of the following – ionizing radiation, pulsed light or UV-C radiation.

11. Which of the following is used for ionizing radiation?
a) Infrared radiation
b) Microwave radiation
c) Radiowave radiation
d) Gamma radiation
Answer: d
Clarification: Gamma radiation is used for ionizing radiation. It can also be done by X rays, electron beams, or higher energy rays, i.e. short wavelengths (less than 1 nanometer). It acts by dislodging electrons from atoms and form ions.

12. Which of the following is a chemical used in aseptic packaging?
a) Chlorine peroxide
b) Lithium oxide
c) Hydrogen Peroxide
d) Hydrogen Sulfide
Answer: c
Clarification: Hydrogen Peroxide is a chemical used in aseptic packaging. It acts by producing peroxide ions which kill pathogens. Other than this, peracetic acid is also used as a chemical sterilant.

13. Canning is also known as aseptic packaging.
a) True
b) False
Answer: b
Clarification: The given statement is false. Canning is a conventional food processing method. In canning, the process starts with treating food (by brining or syruping) to inactivate the enzymes. This is followed by filling in cans and sealing.

14. Canning causes less thermal damage when compared to aseptic packaging.
a) True
b) False
Answer: b
Clarification: The given statement is false. Aseptic packaging causes less thermal damage as it uses milder heat treatment – HTST or UHT.

15. Which of the following is used for checking integrity of aseptic packaging material?
a) Sterility test
b) Drop test
c) Bursting test
d) Grammage test
Answer: a
Clarification: Sterility test is used for integrity check for aseptic packaging material. Other integrity check tests are-
• Teardown test – sealing strength
• Electrolytic test – pinhole testing
• Dye test – for pinholes in laminated cartons.

250+ TOP MCQs on Additives in Plastics and Answers

Food Packaging Technology Multiple Choice Questions & Answers (MCQs) on “Additives in Plastics”.

1. Which of the following is not a plastic colorant?
a) Diarylide
b) Tartrazine
c) Sudan stain
d) Oil blue A
Answer: b
Clarification: Tartrazine is not a plastic colorant. It is an artificial dye (Lemon yellow colored) used in foods. Sudan stain and Oil blue A are dyes and Diarylide is a pigment. Colorants are added to plastic to give it a desired colour.

2. What is the function of biostabilizers?
a) To regulate hardness
b) Obtain better impact resistance
c) Control surface tension
d) To prevent deterioration
Answer: d
Clarification: Biostabilizers helps to prevent deterioration of plastic. Biostabilizers are also called as antimicrobials because itdecreases susceptibility of plastic against microbial attack.

3. What is the function of fillers?
a) Increase conductance
b) Reduce sinkage
c) Increase stiffness and hardness
d) Improve ability to absorb shock
Answer: c
Clarification: Fillers help in increasing the stiffness and hardness of a plastic. Substances like photoinitiators increase electrical stability. Impact modifiers improve the ability to absorb shock. Blowing agents reduces sinkage.

4. Are foaming agents used in plastic?
a) True
b) False
Answer: a
Clarification: Foaming agents are also known as blowing agents. They are used during the process of blow moulding, to reduce or eliminate sink marks. It gives a foam structure to the plastic, hence the name foaming agent.

5. Which of the following is not a filler?
a) CaCo3
b) SbO3
c) Silica
d) Asbestos
Answer: b
Clarification: Antimony Trioxide (SbO3) is not filler. Rest of these are fillers used in plastics. Fillers provide rigidity to the plastic, thereby increasing its tensile strength and toughness. It also increases elastic modulus and wear resistance.

6. Which of the following is not a lubricant used in plastic?
a) Silicone oil
b) Low mol wt PE
c) Neoprene
d) Halogens
Answer: d
Clarification: Halogens are not lubricants; they are flame retarders. Silicone oil, low molecular weight polyethylene and neoprene are lubricants. Lubricants are used to prevent any damage caused to plastic during its processing (especially the moulding process).

7. UV Stabilizers are added to plastics?
a) True
b) False
Answer: a
Clarification: UV stabilizers are added to plastics to increase the life of plastics, especially when exposed to UV lights. The following UV stabilizers are generally used- benzotriazoles, alkylated hindered phenol, benzophenones, etc.

8. Anti-oxidants used in plastic.
a) True
b) False
Answer: a
Clarification: Anti-oxidants are used in plastic to prevent oxidation. Plastics deteriorate due to oxidation – unstable melt flow properties, brittleness, discoloration and loss of tensile properties. Following are the commonly used anti-oxidants used in plastics-arylamines, phenols, phosphites and various sulfur compounds.

9. What is the function of plasticizer?
a) Improve rheology
b) Lower glass transition temperature
c) Increase electrical stability
d) Improve strength
Answer: b
Clarification: Plasticizers lower the glass transition temperature of plastics. Therefore, it helps to make the plastic more flexible. It does so by decreasing its viscosity in a way. Rheology is improved by lubricants. Substances like photoinitiators increase electrical stability and fillers improve strength.

10. Which among the following is a UV light absorber?
a) Phosphate esters
b) Quaternary ammonium compounds
c) Polyethylene glycol esters
d) Benzophenones
Answer: d
Clarification: Benzophenone is an additive used in plastics as a UV light absorber. These are used to increase the life of plastic and stabilize its color, mainly caused due to its exposure to sunlight – UV spectrum.

11. Halogens are used as _______ in plastics.
a) Flame retardant
b) UV light absorber
c) Antimicrobial
d) Antistatic agents
Answer: a
Clarification: Halogens are used as fire retardant in plastics. Halogens are generally added to thermoplastics to provide insulation, coat base plastic to exclude oxygen and create an endothermic cooling reaction.

12. Adipate diesters are _________
a) Flame retardant
b) Antimicrobial
c) UV light absorber
d) Plasticizers
Answer: d
Clarification: Adipate diesters are plasticizers used in plastic. Plasticizers are lubricants, which work by decreasing physical boding of the molecules and overcoming forces of attraction amongst them.

250+ TOP MCQs on Paper Making – 2 and Answers

Food Packaging Technology Interview Questions and Answers for Experienced people on “Paper Making – 2”.

1. Which of the following was the first paper making machine?
a) Fourinder machine
b) Cylinder machine
c) Twin-Wire Formers
d) Roller Presses
Answer: a
Clarification: The first paper making machine was Fourdrinier machine of 1804, named after its financiers Henry and Sealy Fourdrinier, two prosperous London stationers who purchased the patent interests of the Frenchman Didot Frères. In this, paper is made by depositing a very dilute suspension of fibers from a very low consistency aqueous suspension (greater than 99% water) on to a relatively fine woven screen, over 95% of the water being removed by drainage through the wire. The fibers interlace in a generally random manner as they are deposited on the wire and become part of the filter medium.

2. Paper greater than ________ is considered paperboard.
a) 300 μm
b) 200 μm
c) 500 μm
d) 400 μm
Answer: a
Clarification: Paper greater than -2 (i.e., grams per square meter or GSM).

3. _________ are used to produce heavy multi-ply boards.
a) Fourinder machine
b) Cylinder machine
c) Twin-Wire Formers
d) Roller Presses
Answer: b
Clarification: Cylinder machines are used to produce heavy multi-ply boards. They produce a sheet that is much stronger in the direction of flow than that produced on Fourdrinier machines. A cylinder covered with a wire cloth is rotated partially submerged in a stock suspension. Because of a vacuum applied inside the cylinder, water drains inward through the wire cloth, and the paper web is formed on the outside. The web is picked up by a felt, which is pressed onto the top of the cylinder by a rubber roll. A series of vats provide individual plies of fiber which are subsequently matted together.

4. ___________ are particularly used for lightweight sheets, corrugated media and linerboard grades.
a) Fourinder machine
b) Roller Presses
c) Twin-wire formers
d) Cylinder machine
Answer: c
Clarification: Twin-wire formers are particularly used for lightweight sheets, corrugated media and linerboard grades. In this, the paper web is formed between two converging forming screens by means of a flow box and the water is drained from the slurry by pressure and later by vacuum. A typical twin-wire forming unit is the inverform, which was designed to provide a new method for the manufacture of single and multi-ply sheets at high speeds. Successive layers of fiber are laid down sequentially on the felt, with water being removed upwardly, overcoming the difficulty experienced in the conventional downward removal of water through several layers of board at high speed.

5. The moisture content of the paper sheet before entering the dryer is _______
a) 35%–40%
b) 35%–50%
c) 45%–60%
d) 75%–90%
Answer: d
Clarification: After leaving the forming fabric of the papermaking machine, the sheet (which has a moisture content of 75%–90% depending on type) passes to the press and dryer sections for further water removal.

6. The moisture content of the paper sheet after passing through the rotary presses is _______
a) 80%–90%
b) 60%–70%
c) 40%–50%
d) 10%–20%
Answer: b
Clarification: Rotary presses (which may have solid or perforated rollers, often with internal suction) receive the sheets on continuous felts, which act as conveyers and porous receptors of water. On leaving the press, the moisture content is typically 60%–70%, again depending on type.

7. The final moisture content of paper after pressing and drying is __________
a) 4%–10%
b) 10%–20%
c) 1%–5%
d) 40%–50%
Answer: a
Clarification: The paper is after passing through a series of steam-heated rollers is dried to a final moisture content between 4% and 10%. Other types of dryers are used for special products or situations. For example, the Yankee dryer is a large, steam-heated cylinder, which dries the sheet from one side only, and is used extensively for tissues and to produce machine glazed (MG) papers, the latter having a glazed or shiny surface from intimate contact with the polished dryer surface.

8. The application of chemicals to the surface of a paper web is done with _______
a) Stew press
b) Scaling press
c) Screw press
d) Size press
Answer: d
Clarification: The application of chemicals to the surface of a paper web is done with a size press. In a size press, the dry paper is passed through a flooded nib, where a dispersion of functional chemical contacts both sides of the paper. Excess liquid is then squeezed out in the press and the paper is re-dried.

9. An optimum concentration of coating solution for improving water resistance of paperboard is _____
a) 1.5 w/v%
b) 2.5 w/v%
c) 3 w/v%
d) 1 w/v%
Answer: c
Clarification: An optimum concentration of coating solution for improving water resistance of paperboard was 3 w/v %. It gives a coating thickness of 28 μm equivalent to 49.5 GSM. There is an increase in the water resistance of paperboard when it is coated with PLA. A coating thickness between 4.7 to 42.7 μm decreases water vapor permeability from 4.8 to 25.5 times, while decreasing water absorptiveness from 11.9 to 17.9 times.

10. __________ are widely used in paper coatings for oil and moisture resistance in microwave popcorn bags.
a) Chlorochemicals
b) Hydrogen peroxide
c) Fluorochemicals
d) Polyphenols
Answer: c
Clarification: Fluorochemicals are widely used in paper coatings for oil and moisture resistance in microwave popcorn bags. It is also used in fast-food paper packaging for muffin and french-fry bags, sandwich/burger wrappers and small pizza and burger boxes. The perfluorocarbon moiety in these classes of products has the effect of lowering the surface energy of the individual paper fibers which greatly contributes to the holdout of low surface energy liquids such as greases and oils.

11. Pigments are added at the wet end of the paper machine and serve to fill the sheet.
a) True
b) False
Answer: b
Clarification: The given statement is false. Though functionally and chemically similar, fillers and pigments are distinguished from one another in that fillers are added at the wet end of the paper machine and serve to fill the sheet; pigments are added at the size press and serve to alter the surface of the sheet.

12. Pigments comprise ______ of the dry solids in paper coatings.
a) 10%–30%
b) 70%–90%
c) 40%–50%
d) 60%–90%
Answer: b
Clarification: Pigments comprise 70%–90% of the dry solids in paper coatings. They are generally designed to mask or change the appearance of the base stock, improve opacity, impart a smooth and receptive surface for printing or provide special properties for particular purposes.

13. Paper has a definite caused by the greater orientation of fibers.
a) Yield
b) Strain
c) Stretch
d) Grain
Answer: d
Clarification: Paper has a definite grain caused by the greater orientation of fibers, in the direction of travel of the paper machine, and the greater strength orientation that results partly from the greater fiber alignment and partly from the greater tension exerted on the paper in this direction during drying.

14. The grain direction is known as the machine direction (MD), while the cross direction (CD) is the direction of the paper at right angles to the MD.
a) True
b) False
Answer: a
Clarification: The given statement is true. The grain direction is known as the machine direction (MD), while the cross direction (CD) is the direction of the paper at right angles to the MD. The grain of paper must be taken into account in measuring all physical properties. Most of the physical properties of paper depend on direction, that is, the MD, CD and thickness direction (z-direction).

15. Usually, there is less variation in paper properties in the MD than in the CD.
a) True
b) False
Answer: a
Clarification: The given statement is true. Usually, there is less variation in paper properties in the MD than in the CD. It is because variations occur slowly in the MD, whereas in the CD they may occur quite suddenly for a variety of process related reasons. In addition, the CD strength normally varies depending on how far the sample was taken from the edge of the sheet.

250+ TOP MCQs on Food Packaging Materials – 1 and Answers

Food Packaging Technology Multiple Choice Questions & Answers (MCQs) on “Food Packaging Materials – 1”.

1. Which of the following is used to pack carbonated soft drinks?
a) HDPE
b) PET
c) PS
d) PVC
Answer: b
Clarification: PET – Polyethylene Terephthalate is widely used to pack carbonated soft drinks. The PET bottle is usually fitted with either a standard aluminium roll-on closure or a pre-threaded plastic cap, both either in the standard or pilfer-proof form.

2. Which of the following is used to pack fried snack foods?
a) LDPE
b) PET
c) PS
d) PVC
Answer: a
Clarification: LDPE- Low Density Polyethylene is widely used to pack fried foods. Paperboard cans lined with a barrier polymer such as aluminium foil is sealed with LDPE-foil end.

3. Which of the following is used to pack coffee?
a) PET & LDPE
b) HDPE
c) HDPE & PS
d) PET & PVC
Answer: a
Clarification: Metalized PET laminated to LDPE is frequently used to pack coffee. This layer of polymer prevents staling and loss of flavor volatiles or chemical changes in the volatile components caused by moisture and O2 absorption.

4. Which of the following is used for packaging of milk in pouches?
a) Polyvinyl
b) Polyethylene Terephthalate
c) Polyethylene
d) Polyester
Answer: d
Clarification: Polyester pouches are used for packaging milk. Packaging materials used for milk should ideally not transmit more than 8% of incident light at 500nm wavelength and not more than 2% at 400nm wavelength. Other materials used for the same include – polypropylene, polystyrene, poly vinyl chloride, polyvinyldiene chloride (cryovac), rubber hydrochloride (pliofilm), polyester, polyamide (nylon), saran (a mixed polymer).

5. Which of the following materials is used in packaging yoghurt in cups?
a) Low Density Polyethylene
b) Polystyrene
c) Polyvinyl Chloride
d) High density Polyethylene
Answer: b
Clarification: Polystyrene cups are used in packaging yoghurt. Other than yoghurt, it is also used in packaging ice-creams. Amongst all varieties of Polystyrene, thermoformed HIPS(High Impact Polystyrene) in the form of small cups or larger tubs, with either an aluminum foil/plastic laminate or a paper/plastic laminate heat seal lid or closure is used.

6. Which of the following is used for primary packaging of butter?
a) Oiled Paper
b) Kraft Paper
c) Wax Paper
d) Parchment Paper
Answer: d
Clarification: Vegetable parchment is the primary packaging used in butter. The main control points in the packaging of butter include- oxidation, water permeability and vapor permeability. Aluminum foil (0.009 mm thick) laminated either to 40 gsm greaseproof paper or vegetable parchment. Other types of packaging include plastic tubs thermoformed from white-pigmented HIPS or PVC with a tight-fitting lid of the same material.

7. Which of the following material is used as a primary package in biscuits?
a) PE
b) LDPE
c) PVC
d) BOPP
Answer: d
Clarification: BOPP (bioriented polypropylene) filmis used as a primary package in biscuits. For higher quality products, duplex OPP or OPP combinations such as OPP/PE, OPP/PET, OPP/PVdC in the appropriate thickness and sealing range are used. It offers effective barrier against gas, odor and light. The plastic polyfilm is used in combination with an inner aluminium layer of approximately 7 microns.

8. Which of the following material is used as a primary package in bread?
a) HDPE
b) LDPE
c) PS
d) PVC
Answer: b
Clarification: LDPE (Low Density Polyethylene) is used as a primary package in bread. The LDPE bag is sealed with PS tag. Vacuum packaging is not sustainable as crushing could take place. Gas mixture in the packaging usually ranges from 100% CO2 to 50:50 CO2:N2.

9. Which of the following is the abrasion resistance layer in a retort pouch?
a) Polypropylene
b) Nylon
c) Aluminum Foil
d) Polyester
Answer: b
Clarification: Nylon is the abrasion resistance layer in a retort pouch. Propylene is the physical food contact layer (primary package). It is a heat seal surface and provides flexibility.

10. Which of the following polymer is used as a printing surface?
a) Polypropylene
b) Nylon
c) Aluminum Foil
d) Polyester
Answer: d
Clarification: Polyester is the printable surface as well as the outermost layer in a retort pouch. It also provides strength. Aluminum foil is the barrier layer of a retort. It protects from light, gases and odors.

11. Tetrapak has _______ layers.
a) 4
b) 5
c) 6
d) 7
Answer: c
Clarification: Tetrapak has 6 layers. The innermost to outermost layers are –
i) Polyethylene (innermost)
ii) Paper
iii) Polyethylene
iv) Aluminium
v) Polyethylene
vi) Polyethylene (outermost).

12. What is the function of Polyethylene in Tetrapak?
a) Mechanical rigidity
b) Gas barrier
c) Abrasion resistance
d) Liquid barrier
Answer: d
Clarification: Polyethylene serves multiple functions in Tetrapak (paperboard carton). The innermost layer is used as a liquid barrier and to bind layers of aluminum, primary layer, paper, printing layer together.

13. Which is the thinnest layer in Tetrapak?
a) Polyethylene
b) Paper
c) Nylon
d) Aluminium
Answer: d
Clarification: Aluminium foil is the thinnest layer in Tetrapak(paperboard carton). It is around 7 microns in width. Aluminium provides the best gas barrier and prevents exposure to sunlight.

14. Which is the thickest layer in Tetrapak?
a) Polyethylene
b) Paper
c) Nylon
d) Aluminium
Answer: b
Clarification: Paper is the thickest layer in Tetrapak. Tetrapak is also known as paperboard carton because of the same. Paper is bound to other layers by polyethylene.

15. Nylon is used in Tetrapak.
a) True
b) False
Answer: b
Clarification: The given statement is false. Nylon is not used in Tetrapak. It is used in retort pouches instead. Nylon acts as an abrasion resistance surface in retort packets. However, in Tetrapak paper is used to provide mechanical rigidity. Paper is combined with polyethylene film for abrasion resistance.

250+ TOP MCQs on Edible, Biobased and Biodegradable Food Packaging Materials and Answers

Food Packaging Technology Multiple Choice Questions & Answers (MCQs) on “Edible, Biobased and Biodegradable Food Packaging Materials”.

1. Which amongst the following is not a food grade polymer?
a) Ethylene Propylene Diene monomer
b) Polyurethane
c) Polyvinyl Chloride
d) Viton
Answer: c
Clarification: Polyvinyl Chloride (PVC) is not a food grade polymer. It is toxic in nature. A polymer is a labeled food grade when it is inert and doesn’t react with food in a harmful manner. Ethylene propylene diene monomer, polyurethane and viton are food grade polymers.

2. Traditional packaging is more sustainable than edible packaging.
a) True
b) False
Answer: b
Clarification: Edible packaging material is more sustainable than traditional packaging material. It is because of its biodegradable property. Traditional packaging material leaves residues on degrading, whereas edible packaging does not. Therefore, making it more sustainable and suitable for the environment.

3. Which of the following is not a mechanism of film formation in edible coating?
a) Simple co-acervation
b) Complex co-acervation
c) Polymerisation
d) Gelation
Answer: c
Clarification: Polymerisation is not a mechanism of film formation in edible coating. Simple co-acervation, compound co-acervation and gelation are mechanisms of film formation in edible coating. Polymerisation is a phenomenon when monomers combine together to form a polymer. Film formation mechanisms are those which tell about the interaction of film and the substrate.

4. ____________ and ___________ are used to make edible packaging material.
a) Minerals and vitamins
b) Proteins and vitamins
c) Water and proteins
d) Proteins and carbohydrates
Answer: d
Clarification: Proteins and carbohydrates are used to make edible packaging material. The protein based material includes-gluten, zein, soy,etc. Carbohydrates based material includes-chitosan, cellulose, dextrin, pectin,etc.

5. _________ is a protein based material for edible coating.
a) Chitosan
b) Acylglycerol
c) Collagen
d) Alginate
Answer: a
Clarification: Collagen is a protein based material for edible coating. Chitosan and alginate are polymer based material for edible coating. Acylglycerol is a lipid based material for edible coating.

6. Complex co-acervation includes addition of hydrosoluble non-electrolyte.
a) True
b) False
Answer: b
Clarification: Simple co-acervation includes addition of hydrosoluble non-electrolyte. Complex co-acervation is simple precipitation of polymer complex, when two hydrocolloids of opposite charges are mixed.

7. Gelation is a ________ of formation of edible coating.
a) Consequence
b) Mechanism
c) Result
d) Prerequisite
Answer: b
Clarification: Gelation is a mechanism of formation of edible coating. Gelation is a process when the heating of polymers leads to its denaturation, followed by gelation or coagulation on cooling. Gelation is also known as thermal coagulation.

8. Edible packaging has comparable water vapor transmission rates.
a) True
b) False
Answer: a
Clarification: Biobased polymers are generally hydrophilic in nature. So are many traditional polymers like nylon, ethylvinyl alcohol, etc. Permeability may increase when humidity increases in both cases. Hence, we can say that edible packaging has comparable water vapor transmission rates.

9. Cohesive forces between ___________ is a principal of film formation.
a) Inner membrane and cell wall
b) Film and substrate
c) Endocarp and mesocarp
d) Polymer molecules
Answer: d
Clarification: Cohesive forces between polymer molecules are a principle of film formation. It is responsible for the barrier properties of the film. It helps in decreasing the permeability and hence transmission rates of gases and water respectively.

10. Adhesive forces between _______________ is a principal of film formation.
a) Polymer molecules
b) Inner membrane and cell wall
c) Film and substrate
d) Endocarp and mesocarp
Answer: c
Clarification: Adhesive forces between film and substrate are a principle of film formation. It is responsible for keeping the film intact. This forms an edible film, which can be consumed along with the food.

11. Which of the following properties make edible/biodegradable packaging material better than the traditional packaging material?
a) Compostability
b) Water vapor transmission rate
c) Oxygen transmission rate
d) Thermal properties
Answer: a
Clarification: Compostability makes edible/biodegradable packaging material better than the traditional packaging material. Compostability is also known as biodegradability. It is the property when the package meets its end life, how well a material decomposes. Biodegradable packets degrades faster and better than the traditional polymers.

12. Which of the following statement is false about edible/biobased packaging material when compared to traditional packaging material?
a) Improved product flavor
b) Resistance to oxygen permeability
c) Low water vapor permeability
d) More sustainable
Answer: c
Clarification: Edible / biobased packaging material has a higher water vapor permeability than traditional packaging material. However it is better than traditional packaging material since it helps improving product flavor, has a higher resistance to oxygen permeability and is more sustainable.

13. Chitosan, a polymer based material for edible coating, also has _______ properties.
a) antifungal
b) antioxidant
c) antifogging
d) thickening
Answer: a
Clarification: Chitosan, a polymer based material for edible coating, also has antifungal properties. Chitosan is used as an edible coating in cucumbers and bell pepper, where its primary function is – moisture barrier.

14. What does PHB stand for?
a) Polyhydrobutyl
b) Polyhydroxybutyrate
c) Polyhydroxybutene
d) Polyhydroxybutane
Answer: b
Clarification: PHB stands for Polyhydroxybutyrate. It is a polyester, popular as a food grade packaging material for snacks, dry products and etc. It is a biodegradable semi-crystalline thermoplastic material produced via fermentation of renewable carbs.

15. CEN headquarters are located in __________
a) Brussels
b) London
c) New York
d) Rome
Answer: a
Clarification: CEN (European Committee for Standardisation) headquarters are located in Brussels, Belgium. It is responsible for the preparation of certain standards on compostability, in order to increase sustainability.