Food Processing and Engineering

(Bonus) For fluids, flowing through a pipe. Name the four parameters included in the calculation of Reynolds number.

Viscosity, pipe diameter, velocity, density (Re: Dv(rho)/(nu))

What are the effects of drying on nutrition?

Vitamin losses, protein - loss of biological value, the most susceptible nutrients to dehydration: unsaturated lipids, proteins, vitamin C

What are the SI units for work, pressure, and energy?

Watts, pascals, joules

Discuss the pressure differences between a pump placement and the design of the system and the implications of each?

Where you have the pump, directly before it there is really low pressure caused by vacuum and right after it you have really high pressure which gradually becomes lower. Depending on where you have the pump, if something breaks, the high pressure will flow towards the low pressure, so you don't want the high pressure to be where the raw milk is causing it to flow into the pasteurized milk because then you will lose the whole batch from cross contamination because the milk is now already past the sterilization point, but it the high pressure is with the treated milk, it will flow back to the raw and will not contaminate the already processed milk.

What is the difference between white, milk and dark chocolate wrt cocoa contents?

White chocolate: cocoa butter, sugar and milk solids but not cocoa solids Milk: cocoa solids, cocoa butter, sugar, milk solids Dark: higher cocoa content, may include cocoa butter and sugar

Thermal processing relies on understanding heat resistance. Define z-value and F-value.

z-value is the temperature change required to change the D-value by a factor of 10. F-value is the total time required at a specific reference temperature to achieve a specific level of microbial destruction (lethality).

For the chemical reaction CaCO3 --> CaO + CO2 (g) at 298K at equilibrium, which of the following is true? (a) ?G=0 (b) ?H=0 (c) ?S=0 (d) all of above

(a) ?G=0

According to the U.S. government, food irradiation is regulated as which of the following? (a) a process; (b) an additive; (c) a unit operation; (d) a genetically modified ingredient

(b) an additive

Log mean temperature difference is used instead of simple temperature difference in: (a) freezing foods in plate freezers; (b) heating in a liquid-liquid heat exchanger; (c) cooking in a steam kettle, (d) all of the above

(b) heating in a liquid-liquid heat exchanger

Which of the following is the SI unit for viscosity? (a) N-m (b) Pa-s (c) N/m (d) J/ K

(b) Pa-s

A Newton is defined as which of the following? (a) The work done when a point of application of 1kgm/s2 is displaced a distance of 1m (b) The force that gives a mass of 1 kg an acceleration of 1m/s2 (c) The power that give rise to the production of energy at the rate of 1 m2kg/s2 (d) None of the above

(b) The force that gives a mass of 1 kg an acceleration of 1m/s2

A unit of lethality can be expressed as which of the following? (a) The time needed to reduce the bacterial load by a 1 log cycle reduction; (b) The heat kill equivalent to 1 min. at 121ºC against an organism with an 18º z-valve; (c) The number of organisms destroyed during a thermal process; (d) All of the above

(b) The heat kill equivalent to 1 min. at 121ºC against an organism with an 18º z-valve

For a mixture of gases in a container, the total pressure exerted is the sum of the pressures that each gas would exert if it were alone. Which law is it? (a) Boyles' (b) Charles' (c) Dalton's (d) Avogadro's

(c) Dalton's

For a chemical equation such as H+ + OH- = H20 at equilibrium at 25?C, which of the following is always true? (a) S = 0 (b) H = 0 (c) G = 0 (d) all of above

(c) G = 0

Which of the following are the standard temperature and pressure conditions according to IUPAC? (a) 25 C at 1 atm (b) 25 C at 1 bar (c) 0 C at 1 atm (d) 0 C at 1 bar

(d) 0 C at 1 bar (current IUPAC definition, older definitions said 0 C at 1 atm

How are the following enzymes or biochemical reactions used by the food industry? a. acetaldehyde reduction by yeast; b. invertase; c. production of carbon dioxide by Propionibacterium; d. pectinases in the beverage industry

a. acetaldehyde reduction makes ethanol; b. invertase makes liquid-filled candies and invert sugar; c. Probionibacterium is used in the production of Swiss cheese; d. pectinases are used in the clarification of juices

Which of the following modes of heat transfer are used in the retort: A.conduction, B.Convection, or C.Radiation?

A. Conduction and B. Convection

which of the procedures listed is designed to kill most microorganisms: A.radappertization, B.radicitation, or C.radurization?

A. radappertization

The increase in kinetic energy of a flowing fluid is at the expense of what? a) pressure drop b) Reynolds number c) viscosity

a) pressure drop

How many pecks are in a bushel? 2, 4, 8, 16

b. 4