LAISHA
Open Laisha

ICAR AIEEA-PG / PGS Fruit & Vegetable Processing Technology: practice questions

ICAR AIEEA-PG / PGS — Code 18 Food Science Technology · India · ICAR through the National Testing Agency

Original practice questions written to the published syllabus · not past papers
10worked here, free
107written to this exam in this subject
14syllabus units

What this subject covers

Processed products from fruits and vegetables: juices and concentrates, jams, jellies and marmalades, pickles, sauces and ketchup, dried and frozen products, canned products and minimally processed produce, with pectin chemistry and by-product recovery. Packhouse and storage engineering are in Agricultural Engineering's post-harvest-horticultural-crops.

In the exams: GATE XE-G Section 3 (fruits and vegetables processing; pectin from fruit wastes); ICAR AIEEA-PG Code 18 Unit III; ICAR AICE 35.a Unit 2

What ICAR AIEEA-PG / PGS asks from it

ICAR AIEEA-PG / PGS — Code 18 Food Science Technology

Unit III names the technology of fruits and vegetables and by-products. Questions are MCQs on definitions and classic specifications (RTS, nectar, squash, cordial, jam end point), pectin tests, jelly defects (syneresis, crystallisation), peeling methods, lacquers for cans, sulphuring, candying, pickle microbiology and defects, and tomato product terms (Bostwick, Howard mould count).

Where the 107 questions fall

How our questions for ICAR AIEEA-PG / PGS spread across the units of Fruit & Vegetable Processing Technology. Difficulty: 30 easy, 62 medium, 15 hard.

Squashes, cordials, nectars and ready-to-serve beverages9
By-product utilisation: pectin, peel and pomace9
Preparation for processing: washing, peeling, cutting and blanching8
Fruit juices: extraction, clarification, concentration and packaging8
Pectin chemistry and gel formation8
Jams, jellies, marmalades and fruit preserves8
Tomato products: juice, puree, paste and ketchup8
Canning of fruits and vegetables8
Dehydrated and frozen fruits and vegetables8
Composition and processing quality of fruits and vegetables7
Pickles, chutneys and sauces7
Potato products7
Candied fruits6
Minimally processed fresh-cut produce6

10 practice questions, worked

Choose an answer, then open the working. Each explanation says why the right answer is right and why the others are not.

1 · Preparation for processing: washing, peeling, cutting and blanching · easy

Lye peeling of peaches removes the skin by

  1. Hot alkali dissolving the pectin under the skin
  2. Abrasive rollers rubbing the skin away mechanically
  3. Sudden release of steam pressure lifting the skin
  4. Burning the outer skin off in a gas flame
Answer and working

A. Hot alkali dissolving the pectin under the skin

Hot sodium hydroxide attacks the pectic material under the skin so the skin washes off; the fruit is then rinsed and often dipped in weak acid. Abrasion, steam-flash and flame peeling are separate methods used for other crops.

Further reading: Fellows, Food Processing Technology

2 · Squashes, cordials, nectars and ready-to-serve beverages · hard

100 kg of RTS beverage must contain 10% juice, 10% TSS and 0.3% acidity as citric acid. The juice used has 10 °Brix and 1.0% acidity. Ignoring the soluble solids contributed by added acid, how much sugar must be added?

  1. 10.0 kg
  2. 8.0 kg
  3. 9.0 kg
  4. 1.0 kg
Answer and working

C. 9.0 kg

The 10 kg of juice brings 10 × 0.10 = 1.0 kg of soluble solids. The beverage needs 100 × 0.10 = 10 kg, so sugar = 10 − 1 = 9.0 kg. 10 kg ignores the juice's own solids; 1.0 kg is the solids from juice; 8.0 kg double-counts them.

Further reading: Girdhari Lal, Siddappa and Tandon, Preservation of Fruits and Vegetables

3 · Jams, jellies, marmalades and fruit preserves · medium

Sucrose crystals form in a stored jam. The most likely processing fault is

  1. Too much pectin
  2. Too little inversion
  3. Too long a boiling time
  4. Too much acid added
Answer and working

B. Too little inversion

Insufficient inversion, for example from low acid or very short boiling, leaves too much sucrose, which crystallises. Long boiling and high acid increase inversion, and excess pectin affects firmness, not crystallisation.

Further reading: Girdhari Lal, Siddappa and Tandon, Preservation of Fruits and Vegetables

4 · Jams, jellies, marmalades and fruit preserves · hard

Why is vacuum boiling sometimes used for high-quality jams?

  1. It increases sucrose inversion and so prevents crystallisation
  2. It removes the need for pectin by concentrating the fruit fibre
  3. It sterilises the jam so that hot filling becomes unnecessary
  4. Lower boiling temperature saves colour and flavour
Answer and working

D. Lower boiling temperature saves colour and flavour

Under vacuum the jam boils at a lower temperature, so browning, pectin degradation and loss of fresh flavour are reduced. Lower temperature actually reduces inversion, pectin is still needed, and the product still needs hot filling or pasteurisation.

Further reading: Girdhari Lal, Siddappa and Tandon, Preservation of Fruits and Vegetables

5 · Canning of fruits and vegetables · medium

Canned sweet corn shows black staining on the inside of the can. The lacquer that prevents this contains

  1. Calcium chloride
  2. Citric acid
  3. Sodium benzoate
  4. Zinc oxide
Answer and working

D. Zinc oxide

Sulphur released from proteins forms black iron or tin sulphide; sulphur-resistant C-enamel contains zinc oxide, which forms white zinc sulphide instead. The other substances are not lacquer components.

Further reading: Fellows, Food Processing Technology

6 · Canning of fruits and vegetables · medium

Canned pears with a pH close to 4.6 are processed in boiling water after citric acid is added to the syrup. This practice is called

  1. Acidification
  2. Exhausting
  3. Syneresis
  4. Inversion
Answer and working

A. Acidification

Adding acid to bring a borderline fruit clearly below pH 4.6 is acidification; it makes a boiling-water process adequate. Exhausting removes air, syneresis is gel weeping, and inversion is hydrolysis of sucrose.

Further reading: Fellows, Food Processing Technology

7 · Dehydrated and frozen fruits and vegetables · medium

Grapes for raisins are dipped in an alkaline emulsion of oils before drying to

  1. Bleach the skin to a golden colour
  2. Crack the waxy bloom and speed drying
  3. Add oil that prevents raisins sticking
  4. Inactivate polyphenol oxidase completely
Answer and working

B. Crack the waxy bloom and speed drying

The dip disrupts the waxy cuticle so water escapes faster. Golden colour comes from sulphuring, the dip is not a coating for stickiness, and it does not reliably inactivate enzymes.

Further reading: Fellows, Food Processing Technology

8 · Potato products · easy

Potatoes for chips (crisps) should have

  1. High dry matter and low reducing sugars
  2. Low dry matter and high reducing sugars
  3. High reducing sugars for golden colour
  4. High water content for crispness
Answer and working

A. High dry matter and low reducing sugars

High dry matter gives yield and crisp texture with less oil uptake; low reducing sugars limit Maillard darkening and acrylamide. High sugars give dark, bitter chips, and high water gives soggy, oily chips.

Further reading: Talburt and Smith, Potato Processing

9 · Potato products · medium

Potatoes stored at 4 °C give dark chips. The reason is

  1. Cold storage destroys the tuber's starch granules
  2. Cold-induced sweetening raises reducing sugars
  3. Low temperature raises the tuber's asparagine to toxic levels
  4. Cold storage lowers dry matter by water uptake
Answer and working

B. Cold-induced sweetening raises reducing sugars

Below about 8–10 °C, starch breakdown to sugars outpaces their use, so glucose and fructose accumulate and brown during frying. Starch granules remain, asparagine levels are not the main change, and dry matter is not lowered by water uptake.

Further reading: Talburt and Smith, Potato Processing

10 · By-product utilisation: pectin, peel and pomace · medium

Mango processing waste is valued because mango kernels yield

  1. A protease used to tenderise meat
  2. An essential oil rich in d-limonene
  3. A fat used in confectionery fat blends
  4. A pectin that sets without any sugar
Answer and working

C. A fat used in confectionery fat blends

Mango kernel fat has a fatty acid profile suited to confectionery fat blends. Proteases come from pineapple or papaya, d-limonene from citrus peel, and pectin from mango peel still needs sugar and acid if it is HM pectin.

Further reading: May, Industrial pectins, Carbohydrate Polymers

Ten here, 107 in the app. The Laisha app has every practice question we have written to ICAR AIEEA-PG / PGS in this subject, marked as you go, with timed papers, a jump-to-unanswered list and a certificate when you pass at 70 per cent.

Free for ten days, then one subscription of US$10 a month. We would rather say so here than have you find it later.

Practise the full set in Laisha →

Read the subject

Fruit & Vegetable Processing TechnologyThe full study manual, free ICAR AIEEA-PG / PGSFormat, sections and how it has changed

More ICAR AIEEA-PG / PGS practice

Food Plant Design, Hygienic Engineering, Utilities & AutomationGeneral MicrobiologyHuman Nutrition & Nutritional Quality of Processed FoodsBeverage Technology: Soft Drinks, Tea, Coffee, Cocoa & Alcoholic BeveragesFood Microbiology: Spoilage, Pathogens & DetectionFish & Seafood Processing TechnologyTraditional, Ethnic & Indigenous Foods TechnologySpices, Herbs, Essential Oils & Flavour TechnologyMeat, Poultry & Egg Products TechnologySugar, Sweeteners, Chocolate & Confectionery TechnologyDairy Science & Technology for Food TechnologistsFood Chemistry I: Water, Carbohydrates, Proteins & LipidsPrinciples of Food Science & Food PreservationFermentation Technology & Food BiotechnologyFood Industry Management, Costing & EntrepreneurshipMechanical Unit Operations: Size Reduction, Mixing & SeparationGeneral Biochemistry & MetabolismPhysical Properties, Rheology & Texture of FoodsFood Analysis: Proximate, Chemical & Instrumental MethodsStatistics, Experimental Design & Chemometrics for Food ScienceCereal Science & Milling TechnologyIn-plant Training, Experiential Learning & ProjectBakery, Pasta & Snack Food TechnologyFood Packaging Science & Technology

Fruit & Vegetable Processing Technology for other exams

GATE · IndiaGATE · IndiaICAR AICE-JRF/SRF · India

Ask Laisha about this

Opens Laisha's chat with your question ready to send. Sign in or start free.