This set of Fermentation Technology Multiple Choice Questions & Answers (MCQs) focuses on “Large Capacity Fermenters”.
1. The capacity of cylindrical fermenters is __________
a) 400 – 1000 hl
b) 500 – 1000 hl
c) 1000 – 2000 hl
d) 500 – 2000 hl
Explanation: The capacity of the cylindrical fermenters is 500 – 1000 hl. The cylindrical vessel is oriented in a horizontal and vertical plane and is of a closed design and have good hygienic properties and carbon dioxide collection is possible.
2. Who developed the cylindroconical fermenters?
Explanation: Nathan developed and designed the style of cylindroconical fermenters in 1930 at the end of the nineteenth and initially introduced in Switzerland. It was used to improve the efficiency of the traditional lager fermentation.
3. The original Nathan vessels were constructed from ___________
Explanation: The original Nathan vessels were constructed from Aluminium. This was a disadvantage that the propensity of aluminium to corrode was not fully understood and this did little for their reputation.
4. Aluminium in Nathan’s vessels was replaced by ________
c) Stainless steel
Explanation: Aluminium in Nathan’s vessel was replaced by stainless steel. Stainless steel consists of a film which is composed of nickel, chromium, etc. which increases the resistance of the vessel to corrosion.
5. What is the diameter of cylindroconical vessel?
a) 1.2 – 3.0 m
b) 4.0 – 4.2 m
c) 5.0 – 5.5 m
d) 3.0 – 4.0 m
Explanation: The diameter of the cylindroconical vessel is 4.0 – 4.2 m. The most common supplied cylindroconical fermentation vessel is of capacity 1500 hl with 12 – 13 m body height, a diameter of 4.0 – 4.2 m and cone with an included angle of 70°. This was reported by Shuttlewood in 1984.
6. The heat transfer is given by ___________
a) Q = UA ΔT
b) U = QA ΔT
c) U = AQ ΔT
d) Q = U ΔT
Explanation: The transfer of heat from beer to coolant involves the combination of convection and conduction. It can be given by heat transfer formula: Q = UA ΔT where Q is the rate of heat transfer, U is the overall heat transfer coefficient, A is the area of the jacket, and ΔT is the difference in temperature between two liquids.
7. The unit rate of heat transfer (Q) is ____________
b) J m2 s-1 K-1
Explanation: The unit of the rate of heat transfer is Joules per second. It is also known as Watts. J m2 s-1 K-1 is the unit of heat transfer coefficient and m2 is the unit of area of the jacket.
8. Which of the following is not an advantage of single-tank operation?
a) Reduction in process time
b) Avoids tank-to-tank transfer
c) Avoids oxygen pick-up
d) Avoids foam formation
Explanation: The avoiding of the formation of foam is an advantage of antifoaming agents or defoamers. The most important advantage of single-tank operation is the reduction in total process time, avoids tank-to-tank transfer and therefore avoiding the possibility of oxygen pick-up.
9. Which of the following company developed the Asahi vessels?
Explanation: Asahi vessels were developed by the Japanese brewing company during the mid-1960s and were designed for uni-tank operation. After Japan, Asahi vessels were also installed in the United States where they were seen as increasing the fermentation and conditioning capacity.
10. The capacity of Asahi vessels is __________
a) 4000 hl
b) 5000 hl
c) 6000 hl
d) 8000 hl
Explanation: The capacity of Asahi vessel is 5000 hl and aspect ratio was close to 1. They were made from stainless steel and were cylindrical in shape with an internal diameter of 7.5 m and height 11.8 m.
11. Who described the single-tank operation?
Explanation: Amaha et al. in 1997 described the use of single-tank operation. The single-tank operation is more advantageous than two-tank operation as there is a reduction in the total process time in single-tank operation.
12. The Rainier uni-tank was designed in ______________
Explanation: The Rainer uni-tank was designed at the Rainier Brewing Company of Seattle, Washington, USA. It was specially designed for single-tank fermentation and conditioning. Hence the name was given as ‘universal tank’.
13. Spheroconical fermenters have a minimal surface area.
Explanation: The spheroconical fermenters have a minimal surface area. The sphere offers many advantages as the sphere is optimal geometry for enclosing the maximum volume within a minimal surface area. Hence, it is cost-effective.
14. Yorkshire square fermenter is a two-vessel system.
Explanation: Yorkshire square fermenter is a one-vessel system. It is a traditional open vessel designed for use with flocculent ale strains. It overcomes the double cleaning disadvantage of the dropping system.
Sanfoundry Global Education & Learning Series – Fermentation Technology.
To practice all areas of Fermentation Technology, here is complete set of 1000+ Multiple Choice Questions and Answers.