India · ICAR through the National Testing Agency · phd
2674practice questions written to this syllabus
53subjects
Format
Computer-based, multiple choice (pattern taken from the existing Laisha ICAR AICE rows; not re-read for these subjects).
Sections
35.a Food Processing Technology: introductory food technology; foods of plant origin; foods of animal origin; food quality management; food engineering, packaging and labelling; food microbiology and biotechnology; flavour chemistry technology; consumer sciences, product development and health foods
35.b Food Safety & Quality: food safety and quality assurance concepts (HACCP, ISO 9000, ISO 17025, NABL, SQC); risk analysis; general principles of food law (sampling plans, FSSAI microbiological criteria, rapid methods); food microbiology; chemistry of milk and milk products; research techniques
41 Processing and Food Engineering: engineering properties; heat and mass transfer; post-harvest unit operations; process technology and machinery; design of processing machinery; material handling, packaging and transport; storage engineering; process plant design; instrumentation and process control
47 Food and Nutrition (community science): food groups; preservation and packaging; cooking and processing; food safety; nutrients; community, life-cycle and clinical nutrition; food service; food analysis
Over the years
Unit headings and content were read in the ICAR AICE-JRF/SRF syllabus PDF. 35.b leans heavily on dairy examples; 37 Dairy Technology is a separate subject served by the Dairy Technology track.
Original questions written to this exam's published syllabus and pattern. Not past papers.
1. In principal component analysis of NIR spectra, the eigenvalues of the covariance matrix are 6.0, 3.0, 0.6 and 0.4. What fraction of total variance do the first two components explain?
60%
95%
75%
90%
Answer and working
D. 90%
Total variance is the sum of the eigenvalues (the trace): 6.0 + 3.0 + 0.6 + 0.4 = 10.0. The first two explain (6.0 + 3.0)/10 = 90%. 60% counts only the first component; 75% divides 9 by 12; 95% adds the third component.
Mathematics for Food Science & Engineering · Eigenvalues, eigenvectors and the Cayley-Hamilton theorem
2. Four flour types are each baked in five replicate loaves in a completely randomised design. How many error degrees of freedom does the one-way ANOVA have?
19
16
12
15
Answer and working
B. 16
Error df = t(r − 1) = 4 × 4 = 16; total df = 20 − 1 = 19; treatment df = 3. 12 is the error df of a randomised block layout, (t − 1)(b − 1); 15 wrongly subtracts the four treatment means plus one from 20.
Statistics, Experimental Design & Chemometrics for Food Science · Analysis of variance: one-way, two-way and multiple comparisons
3. A weak acid preservative has pKa 5.2. What fraction of it is in the ionised (A⁻) form at pH 3.2?
99%
50%
1%
10%
Answer and working
C. 1%
log([A⁻]/[HA]) = pH − pKa = −2, so [A⁻]/[HA] = 0.01 and the ionised fraction = 0.01/1.01 = 1% (99% is undissociated). 50% would be at pH = pKa; 99% is the undissociated fraction, not the ionised one; 10% is close to the ionised fraction one pH unit below pKa (about 9%).
Chemistry for Food Science (General, Organic & Physical) · Acids, bases, pH, buffers and the Henderson-Hasselbalch equation
4. An allosteric enzyme gives a sigmoidal plot of rate against substrate concentration. What does this shape indicate?
Cooperative binding between subunits
That the enzyme follows Michaelis-Menten kinetics with a very low Km
That substrate concentration was measured on a logarithmic scale
That the enzyme has been irreversibly inhibited by the substrate
Answer and working
A. Cooperative binding between subunits
Sigmoidal kinetics arise when binding at one site changes the affinity of others, as in multi-subunit regulatory enzymes; the Michaelis-Menten equation, which gives a hyperbola, does not apply. Irreversible inhibition lowers activity overall; a log scale makes even a hyperbola look sigmoidal, but the question concerns a plot against concentration.
General Biochemistry & Metabolism · Enzymes: classification, mechanism, Michaelis-Menten kinetics and inhibition
5. Viruses were first recognised when tobacco mosaic disease was shown to be caused by an agent that:
Was killed by boiling but not by filtering
Grew on agar but only in the dark
Passed through bacteria-proof filters
Was visible as rods under oil immersion
Answer and working
C. Passed through bacteria-proof filters
Ivanovsky and Beijerinck found that the infectious agent passed bacteria-proof filters; Beijerinck called it a contagium vivum fluidum.
General Microbiology · History and scope of microbiology
Practise it, and prove it
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