Your Answer : (Not Answered)

Correct Answer : B

Monosodium glutamate is used as a flavour enhancer.

MSG is the sodium salt of glutamic acid (INS 621). It has little flavour of its own but intensifies the savoury, meaty taste called umami, which is why it is added to soups, sauces, snacks and processed meats.

It does not sweeten food, so it is not an artificial sweetener. Anti-caking agents, such as silicon dioxide, keep powders free flowing, and MSG has no use as a cleaning agent.

Your Answer : (Not Answered)

Correct Answer : A

The description is that of column chromatography.

Chromatography is classified partly by the shape of the stationary bed. In column chromatography the stationary phase is held in a narrow tube, the column, and the mobile phase is forced through it under pressure (or allowed to flow by gravity). The definition in the question is the standard definition of this form.

In planar chromatography, such as paper and thin-layer chromatography, the stationary phase is a flat layer, not a tube. Liquid and gas chromatography are named after the state of the mobile phase, and each can be run in a column, so neither name describes the tube arrangement the question is asking about.

Your Answer : (Not Answered)

Correct Answer : D

Fat is detected with the ethanol emulsion test.

The sample is shaken with ethanol, in which fats dissolve, and the liquid is then poured into water. If fat is present it comes out of solution as fine droplets, giving a cloudy white emulsion.

The other tests detect other nutrients. The iodine test turns blue-black with starch. Benedict's test gives a brick-red precipitate with reducing sugars. The biuret test turns violet with proteins.

Your Answer : (Not Answered)

Correct Answer : D

The soup provides 118 kcal.

Use the energy factors for each nutrient: 4 kcal per gram of carbohydrate, 4 kcal per gram of protein and 9 kcal per gram of fat. Water supplies no energy.

\[ \begin{aligned} \text{carbohydrate} &= 20 \times 4 = 80 \\ \text{protein} &= 5 \times 4 = 20 \\ \text{fat} &= 2 \times 9 = 18 \\ \text{total} &= 80 + 20 + 18 = 118\ \text{kcal} \end{aligned} \]

80 kcal counts only the carbohydrate. 108 kcal comes from counting fat at 4 kcal a gram instead of 9, and 110 kcal is a near miss with no nutritional basis.

Your Answer : (Not Answered)

Correct Answer : D

The recommended healthy ratio is 1:1.5:1.

FSSAI's guidance on dietary fats gives the healthy ratio of saturated (SFA), monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids as 1 : 1.5 : 1. Dietary fat should therefore come in roughly equal parts of saturated and polyunsaturated fat, with a larger share of monounsaturated fat. This is why FSSAI advises rotating or blending cooking oils rather than relying on one.

1:2:1, 1:3:1 and 2:1:1 are not the ratio FSSAI gives. Some other bodies quote 1:1:1, which is also not offered here.

Your Answer : (Not Answered)

Correct Answer : A

The essential fatty acid is linoleic acid (printed in the paper as 'Linoleinic acid').

The body cannot make linoleic acid, an omega-6 fatty acid, so it must come from the diet. Infants need it for growth, healthy skin and the development of the brain and nervous system, which is why infant formula must contain it; deficiency causes scaly skin and poor growth.

The others are not essential. Palmitic acid is a saturated fat the body makes itself. Omega-9 fatty acids such as oleic acid can also be synthesised. Propionic acid is a short-chain fatty acid used mainly as a preservative.

Your Answer : (Not Answered)

Correct Answer : B

The statement that is NOT correct is an adsorption isotherm exhibits higher equilibrium moisture content than a desorption isotherm in hysteresis.

In sorption hysteresis it is the other way round: at the same temperature and water activity, the desorption isotherm lies above the adsorption isotherm, so a food being dried holds more water than the same food rewetted to that activity.

The other statements are correct. The gap between the two curves is what hysteresis means; at constant moisture content, the temperature dependence of water activity follows the Clausius-Clapeyron equation through the isosteric heat of sorption; and the GAB equation is a three-parameter multilayer model extending BET.

Your Answer : (Not Answered)

Correct Answer : A

The correct match is P-2, Q-4, R-1, S-3.

• Caramelization: browning of sugars heated without amino compounds (2).
• Denaturation: loss of the folded structure of proteins, which inactivates enzymes, as in blanching (4).
• Oxidation: here lipid oxidation, the cause of rancidity in fats and oils (1).
• Bleaching: removal of coloured pigments, as in bleaching of oils, flour or sugar (3).

Caramelization belongs to sugars in every option but one, and the only option that also pairs denaturation with enzymes and bleaching with pigments is P-2, Q-4, R-1, S-3.

Your Answer : (Not Answered)

Correct Answer : A

The correct match is P-4, Q-1, R-2, S-3.

• Lectins bind carbohydrates on red cell surfaces and cause hemagglutination.
• Stachyose, an oligosaccharide of legumes, is not digested in the small intestine; colonic bacteria ferment it, producing gas and flatulence.
• Phytate chelates divalent cations such as iron, zinc and calcium and lowers their bioavailability.
• The Kunitz type inhibitor of soybean inhibits trypsin and chymotrypsin.

The other options swap lectin with the protease inhibitor or with phytate.

Your Answer : (Not Answered)

Correct Answer : D

The measure is the Protein Efficiency Ratio.

PER is defined as the weight gained by a growing animal, usually a weanling rat, divided by the protein it consumed over the test period, under standard conditions. It is one of the oldest biological measures of protein quality.

Net Protein Ratio adds back the weight lost by a protein-free control group. Net Protein Utilization is the fraction of ingested nitrogen retained in the body. The coefficient of digestibility is the fraction of ingested protein absorbed. None of these is weight gain per gram of protein.

Your Answer : (Not Answered)

Correct Answer : D

The amino acid that is NOT essential is L-Arginine.

The nine essential amino acids for adults, which the body cannot make and must get from food, are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Arginine is not among them: adults synthesize it through the urea cycle, so it is classed as non-essential or, in growing children and some illnesses, conditionally essential.

Phenylalanine, valine and lysine are all on the essential list. Lysine is also the limiting amino acid in most cereals, which is why it is often added to cereal-based foods.

Your Answer : (Not Answered)

Correct Answer : C

The anti-nutritional factor in fava bean is vicine.

Faba (fava) beans contain the pyrimidine glycosides vicine and convicine. In people with glucose-6-phosphate dehydrogenase deficiency their aglycones cause oxidative damage to red blood cells and haemolytic anaemia, the condition called favism.

Gossypol is the toxic polyphenol of cottonseed. Curcine is a toxic protein of Jatropha curcas seeds. Cyanogens (cyanogenic glycosides) are typical of cassava, lima beans and bitter almonds rather than faba beans.

Your Answer : (Not Answered)

Correct Answer : C

The pigment with no pro-vitamin A activity is lycopene.

To be converted to vitamin A (retinol) a carotenoid needs at least one unsubstituted β-ionone ring at the end of its chain. Lycopene, the red pigment of tomatoes and watermelon, is an open-chain carotenoid with no ring at either end, so it cannot be cleaved into retinal.

β-Carotene has two β-ionone rings and is the most potent pro-vitamin A. α-Carotene and β-cryptoxanthin each have one such ring, so each yields one molecule of retinal and has roughly half the activity of β-carotene.

Your Answer : (Not Answered)

Correct Answer : C

The correct matching is P-4; Q-3; R-2; S-1.

• Butylated hydroxyanisole (BHA) is a synthetic phenolic antioxidant that traps free radicals (4).
• Mineral oil is used as an anti-foaming agent in food processing (3).
• Tricalcium phosphate keeps powders such as salt free-flowing: an anti-caking agent (2).
• Rice bran wax gives a protective shine to sweets and fruit: a glazing agent (1).

Option B swaps the anti-caking and glazing agents, and the others place BHA or tricalcium phosphate in the wrong class.

Your Answer : (Not Answered)

Correct Answer : D

The compound that does not produce caramel flavour is p-Amino benzoicacid.

The other three are sugar-degradation products with the caramel-like odour: 3-hydroxy-2-methylpyran-4-one is maltol, 2H-4-hydroxy-5-methylfuran-3-one is a hydroxyfuranone of the furaneol type, and 3-hydroxy-2-acetylfuran is isomaltol. All three share the enolized cyclic diketone structure that gives the burnt-sugar note.

p-Aminobenzoic acid is an aromatic amino acid derivative, a B-vitamin-related compound, and is not a caramelization product.

Your Answer : (Not Answered)

Correct Answer : A

The correct matching is P-3; Q-4; R-5; S-2; T-1.

• Vitamin B₁ (thiamine) acts as thiamine pyrophosphate (3).
• Vitamin B₂ (riboflavin) forms flavin adenine dinucleotide, FAD, and FMN (4).
• Pantothenic acid is part of coenzyme A (5).
• Vitamin B₁₂ acts as methylcobalamin and adenosylcobalamin (2).
• Folic acid acts as tetrahydrofolate (1).

Each other option misassigns several pairs, for example thiamine with FAD or coenzyme A, or riboflavin with thiamine pyrophosphate.

Your Answer : (Not Answered)

Correct Answer : C

The process is Retrogradation.

When cooked (gelatinised) starch cools, the linear amylose chains, and more slowly the amylopectin branches, re-associate through hydrogen bonds into ordered, partly crystalline regions. This retrogradation is responsible for the staling of bread and the firming of cooked rice.

Gelatinisation is the opposite step, the swelling and loss of crystallinity of starch granules on heating in water. Syneresis is the weeping of liquid from a gel, which often follows retrogradation but is not the reassociation itself. Denaturation refers to proteins unfolding.

Your Answer : (Not Answered)

Correct Answer : A

The protection comes from tocopherols.

Tocopherols (vitamin E) occur naturally in vegetable oils. They donate a hydrogen atom to lipid peroxyl radicals, breaking the chain reaction of autoxidation, so the oil resists rancidity during storage.

Lipases cause hydrolytic rancidity by freeing fatty acids, so they reduce quality. Moulds and yeasts spoil oils rather than protect them, and refined oils contain essentially no carbohydrates.

Your Answer : (Not Answered)

Correct Answer : B

The low melting point is due to mostly medium chain saturated fatty acids such as lauric acid.

Coconut oil is about 90% saturated, but nearly half of its fatty acids are lauric acid (C12), with much caprylic, capric and myristic acid. Shorter chains have weaker van der Waals attractions between them, so the triglycerides melt at only about 24-26 °C, while fats rich in long-chain saturated acids (such as stearic, C18) stay solid at much higher temperatures.

A large amount of long-chain saturated acids would raise the melting point. Fatty acid chains do not form hydrogen bonds with each other, and plant oils contain essentially no cholesterol.

Your Answer : (Not Answered)

Correct Answer : A

The correct match is P-3, Q-1, R-4, S-2.

• Thiobarbituric acid (TBA) test: measures malondialdehyde and related carbonyl compounds, secondary products of lipid oxidation (3).
• Rancimat method: an accelerated test that blows air through heated fat and reports the induction time before rapid oxidation begins (1).
• Peroxide value: measures hydroperoxides, the primary oxidation products (4).
• Iodine value: the grams of iodine absorbed per 100 g of fat, a measure of the degree of unsaturation (2).

Peroxide value and iodine value are the pair most often confused, and the options that swap them (R-2, S-4) or give induction time to the peroxide value fail on these definitions.