Q1. Bruising of fruits occur due to?

1. Inactivation of enzymes
2. Protein-sugar reaction
3. Release of enzymes
4. Off flavor

ANSWER: C. Release of enzymes

• Explanation: Bruising of fruits occur due to Release of enzymes. Fruits bruise because enzymes are released during handling and storage. Breakage of polysaccharides and their reactivity with embedded proteins can be linked to the hydrolysis of polysaccharides. Rancidity is the formation of off-flavors caused by lipid oxidation in the presence of light and oxygen. The inactivation of enzymes occurs when heat is applied to muscle tissues during processing, resulting in longer shelf life.

READ MORE – Food Science & Technology Quiz (23-01-2022)

Q2. A substance existing as an amorphous (non-crystalline) solid is said to be in a?

1. Detailed solution
2. Glassy state
3. Rubbery state
4. Vitrification

ANSWER: B. Glassy state

• Explanation – A glassy state refers to a substance that exists as an amorphous (non-crystalline) solid. At temperatures, much below sample Tg, relatively tiny molecules, most notably water, retain significant translational and rotational mobility in complex, polymer-dominated systems. Of course, vibrational mobility continues until the temperature is dropped to absolute zero.

READ MORE – Food Science & Technology Quiz (03-02-2022)

Q3. _________ is a term used to describe the viscoelastic nature of large polymers in the temperature range Tm to Tg,

1. Detailed solution
2. Glassy state
3. Rubbery state
4. Vitrification

ANSWER – C. Rubbery state

• Explanation: When a substance or a part of a substance lies between the glassy and liquid states, this phrase is used to characterize the viscoelastic nature of large polymers in the temperature range Tm to Tg. Small polymers and low-molecular-weight solutes found in this temperature range are highly viscous but not elastic and are hence not referred to as rubbery.

READ MORE –Food Science & Technology Quiz (13-02-2022)

Q4. Which among the following polysaccharide molecules have “Egg-box” junctions across links?

1. Gelatin
2. Carrageenan
3. Amylase
4. Alginate

ANSWER: D. Alginate

• Explanation: When divalent cations are present in some charged polysaccharides, such as alginate, “egg-box” connections form. Negative charges on alginates, which are commonly spaced at regular intervals, allow divalent cations like Ca2+ to form bridges between two parallel polymer molecules. As a result, somewhat stiff connections are created. The connections are most likely to rearrange themselves in microcrystalline areas. Unless the temperature is near 100°C, the connections do not readily “melt.”

READ MORE –Food Science & Technology Quiz 23-11-2021

Q5. _______ are a group of homologous oligosaccharides, obtained from the breakdown of starch by the action of cyclodextringlucanotransferase produced by Bacillus macerations.

1. Schardingerdextrins
2. Cyclodextrins
3. Cycloamyloses
4. All of the above

ANSWER: D. All of the above

• Explanation – Cyclodextringlucanotransferase is a Bacillus enzyme that converts starch polymers into rings of (1-4) connected a-D-glucopyranosyl units. The enzyme can produce alpha-, beta-, and gamma-cyclodextrins with six, seven, and eight members, respectively. The shift of a glycosidic bond from one that unites neighboring segments of a spiral to one that forms a doughnut-like circular shape is easy to visualize since the regular helical conformation of a linear part of a starch molecule contains six to sevenglucosyl units per turn of the helix.

READ MORE – Food Science & Technology Quiz (22-02-2022)

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