Food Processing and Engineering

What are the plate type evaporators that are used?

Rising film, falling, parvap (similar to wiped film) and paraflash (similar to forced circulation)

Rank the following membrane separation methods based on increasing pore size: microfiltration, reverse osmosis, nanofiltration, and ultrafiltration.

RO, NF, UF, MF

What are the different types of feeding methods?

Roll feeding, nip feeding, dipping, spray feeding, splashing

What are the different types of atomizers available?

Rotary (wheel) atomizer: spinning discs or vaned wheels or cups. Nozzle atomizer: pressure nozzles and two-fluid nozzles

What are some ways to reduce non-uniform heating during microwave heating?

Rotating food with motorized platter, pre-heating and holding time after the microwave heating, adjusting power settings in microwave ovens

To be called peanut butter the product must contain 90% peanuts. Name 3 items used as the other 10% of peanut butter.

Salt, sugar(sweetener) hardened vegetable oil, or emulsifier

What are 4 steps to ensure a proper natural fermentation of sauercraut?

Salting, shredding, anaerobic storage, low temperatures

Engineers commonly use dimensionless numbers to aid in solving equations; which dimensionless numbers do the following 2-letter abbreviations represent when expressed in the subscript to a capital N: Sc, Re, Nu, Bi?

Sc=Schmidt; Re=Reynolds; Nu= Nusselt; Bi=Biot

What are the applications of centrifugal separation?

Separation of immiscible liquids, clarification by removal of small amounts of solids, removal of solids,(skimming milk, oil refining, brewing, fish protein concentrate, remove cellular material in juice

Name 5 types of heat exchangers used for food processing.

Shell and tube heat exchanger, spiral heat exchanger, plate heat exchanger, jacketed pans, scraped surface heat exchangers, corrugated tube heat exchanger, finned tube heat exchangers, double pipe heat exchanger

What types of evaporators are used in the food industry?

Short tube Long tube (rising and Falling film) Forced-circulation evaporator Wiped film/agitated thin-film evaporator Plate evaporator: rising/falling film Centrifugal/conical evaporator.

What are the advantages of Continuous cryogenic freezing?

Shorter freezing and chilling time: rapid. - Texture damage is minimal. - Smaller equipment. - Oxygen is limited from environment. - Less maintenance required.

What are the steps necessary in sauerkraut production?

Shred cabbage; salt cabbage at 2.25-3%; pack the cabbage to remove air pockets; create an anaerobic environment; hold at 21 degrees C for 3-4 weeks

What are the effects of drying on shrinkage?

Shrinkage (reduction in volume due to moisture loss): biopolymers cannot support their weight in the absence of water, gravity causes to shrink, collapse of cell walls and from gel-like to fibrous, important phenomenon impacting dried food quality (reducing wettability, changing texture, decreasing product absorbency) isotropic anisotropic(fish and seafood, fruit and veg)

What are the different types of drum dryers?

Single drum, double drum (2 drums revolve toward each other @top), twin drum (2 drums rotates away from each other), Vacuum (heat sensitive materials, expensive), perforated/suction (hot air, several drums can be linked)

What are the factors that affect the selectivity of membrane separation?

Size, shape, electrostatic charge, diffusivity, physiochemical interactions, volatility, polarity/solubility

What are the (3-4) benefits of using SO2 in dehydration processing?

SO2 pasteurization, prevention of enzymatic browning, prevention of non-enzymatic browning, retention of Vitamin C.

What are different methods of separation?

Solid liquid (filtration, centrifugation, membrane sep, drying) liquid-liquid (centrifuge, extraction, distillation, membrane sep)

What are the effects of drying on case hardening and crust formation?

Solutes move to surface, evaporation of water causes concentration of solutes at the surface level, high temp cause complex chemical and physical changes and the formation of a hard impermeable skin, aggregations of molecules are not easily disassociated on rehydration, minimized by flattening the concentration gradients, control rate of drying, crust is desirable breakfast cereals long bowl life, undesirable if rehydration necessary. IN sausages, they are drying from the inside out and the moisture removed from the surface is replaced by the moisture coming from inside the sausage. If the surface hardening occurs to fast, the inside moisture may be permanently trapped and bacteria will multiply spoiling the sausage

What are the components of a supercritical fluid extraction system?

Solvent compressor or pump, extractor, temperature/pressure control system, separator/absorber.