GATE 2015 Question Paper with Answer Keys for Food Technology (XL-M)
M: FOOD TECHNOLOGY
Q. 1 – Q. 10 carry one mark each.
Q.1 Standard pasteurization protocol for milk is adequate for destroying
(A) Clostridium sporogenes
(B) Bacillus cereus
(C) Clostridium botulinum
(D) Listeria monocytogenes
Ans: (D) Listeria monocytogenes
Q.2 Which one of the following is NOT a component of an evaporator?
(A) Heat exchanger
(B) Vacuum separator
(C) Condenser
(D) Cyclone separator
Ans: (D) Cyclone separator
Q.3 Among the following animal foods, the fat content is least in
(A) Beef
(B) Chicken meat
(C) Pork
(D) Lamb flesh
Ans: (B) Chicken meat
Q.4 The enzyme that hydrolyzes starch to maltose is
(A) α-amylase
(B) β-amylase
(C) glucoamylase
(D) cyclodextrin glucanotransferase
Ans: (B) β-amylase
Q.5 Which one of the following is NOT enriched in endosperm during parboiling of paddy?
(A) Thiamine
(B) Niacin
(C) Iron
(D) Fat
Ans: (D) Fat
Q.6 Heat-treated legume seed proteins are more digestible than those of untreated legume seed proteins due to
(A) reaction of reducing sugars with ε-amino group of lysine
(B) increased binding of lectins to intestinal mucosal cells
(C) thermolabile nature of lectins and Kunitz-type protease inhibitors
(D) thermolabile nature of Bowman-Birk type of inhibitor
Ans: (C) thermolabile nature of lectins and Kunitz-type protease inhibitors
Q.7 What is the percent relative humidity at which both the dry bulb and wet bulb thermometers would record equal temperatures?
(A) 0
(B) 10
(C) 50
(D) 100
Ans: (D) 100
Q.8 How many fold would the g-number of a centrifuge increase by doubling both the spinning speed and bowl diameter?
(A) 2
(B) 4
(C) 8
(D) 16
Ans: (C) 8
Q.9 Prolonged fermentation of cocoa seeds lead to “off-taste” due to the release of
(A) glucose
(B) short chain fatty acids
(C) carbon dioxide
(D) phospholipids
Ans: (B) short chain fatty acids
Q.10 The gradual decrease in viscosity of tomato paste during storage can be prevented by quickly heating it to 82 °C, because
(A) water soluble pectin interacts with calcium
(B) hemicellulose prevents decrease in viscosity
(C) lignin prevents decrease in viscosity
(D) pectin methyl esterase is inactivated
Ans: (D) pectin methyl esterase is inactivated
Q. 11 – Q. 20 carry two marks each.
Q.11 Match the enzyme in Group I with its corresponding application in Group II
| Group I | Group II |
| (P) Chymosin | (1) Removal of cooked flavor from milk |
| (Q) Sulfhydryl oxidase | (2) Soybean milk coagulation |
| (R) β-Galactosidase | (3) For rennet puddings |
| (S) Microbial proteases | (4) Lactose removal |
(A) P-3, Q-2, R-1, S-4
(B) P-3, Q-1, R-4, S-2
(C) P-1, Q-3, R-4, S-2
(D) P-4, Q-3, R-2, S-1
Ans: (B) P-3, Q-1, R-4, S-2
Q.12 Milk is flowing at 0.12 m3/min in a 2.5 cm diameter pipe. The temperature of the milk is 21 °C and the corresponding viscosity and density are 2.1 x 10-3 Pas and 1029 kg/m3, respectively. If the flow is found to be turbulent under the given conditions, the Reynolds number is _
Ans: 49000 to 50225
Q.13 Whole milk (34,950 kg) containing 4% fat is to be separated in 6 h period into skim milk with 0.45% fat and cream with 45% fat. The flow rate of cream stream (kg/h) from the separator is
Ans: 455 to 475
Q.14 Match the edible plant tissue in Group I with the type of carotenoid given in Group II
| Group I | Group II |
| (P) Corn | (1) Lycopene |
| (Q) Red pepper | (2) β-Carotene |
| (R) Pumpkin | (3) Capsanthin |
| (S) Tomato | (4) Lutein |
(A) P-3, Q-4, R-2, S-1
(B) P-2, Q-1, R-3, S-4
(C) P-4, Q-3, R-2, S-1
(D) P-1, Q-2, R-4, S-3
Ans: (C) P-4, Q-3, R-2, S-1
Q.15 Green tea is considered to be a more healthy option than black tea because it
(A) has high content of polyphenols
(B) is richer in thearubigin
(C) does not require any sweetener during tea preparation
(D) has no microbial load
Ans: (A) has high content of polyphenols
Q.16 A dilute pineapple juice is heated in a double pipe heat exchanger from 28 °C to 75 °C by heat exchanging with hot water flowing in shell in counter current direction. Hot water is entering the
shell at 95 °C and leaving at 85 °C. The log mean temperature difference (°C) is __
Ans: 35.0 to 36.0
Q.17 Granulated sugar, having an average particle size of 500 μm, is milled to produce icing sugar having an average particle size of 25 μm. The power requirement was 10 kW as obtained by
Rittinger’s law. If the same mill were to be used to produce fondant sugar having an average particle size of 20 μm at the same capacity, the power requirement (kW) would be _
Ans: 12.4 to 12.8
Q.18 One ton of soybean containing 18% oil, 35% protein, 27.1% carbohydrates, 9.4% of fibre and ash, and 10.5% moisture is crushed and pressed. The residual oil content in the pressed cake is 6%. Assuming that there is no loss of protein and water with oil, the amount of oil (kg) obtained from the crusher is __
Ans: 127 to 128
Q.19 Match the processing method in Group I with the operation carried out in Group II
| Group I | Group II |
| (P) Degumming | (1) Crystallization of triacylglycerol by cooling to remove fat crystals |
| (Q) Deacidifying | (2) Passing heated oil over charcoal |
| (R) Bleaching | (3) Using alkaline solution to remove fatty acids |
| (S) Winterizing | (4) Wetting with water to remove lecithin |
(A) P-3, Q-1, R-4, S-2
(B) P-4, Q-3, R-1, S-2
(C) P-4, Q-3, R-2, S-1
(D) P-3, Q-1, R-2, S-4
Ans: (C) P-4, Q-3, R-2, S-1
Q.20 The order of succession of microbes in the spoilage of milk, involving (P) Lactobacillus, (Q) protein digesting bacteria, (R) Lactococcus lactis, (S) yeasts and molds, is
(A) S>R>Q>P
(B) S>Q>R>P
(C) R>P>S>Q
(D) Q>S>P>R
Ans: (C) R>P>S>Q
END OF THE QUESTION PAPER