FPP Lab 2-3 Revision: Moist, Dry & Microwave Cooking Methods

Heating foods does what?

• Kill microorganisms

• Alter molecular structure of foods => change in texture, taste, aroma & appearance

Sources for heating foods

• Most common: electricity & gas

• Wood, coal & charcoal

3 methods of heat transfer

• Conduction

• Convection

• Radiation

What happens during convection?

• For liquids and gases

• Cool, dense air => go to bottom

• Hot, less dense air => go to top

• Creates convection current

Is microwave a form of dry heating?

No, it has its own category as it incorporates both wet and dry heating methods

4 factors that affect cooking time

• Water content of food

• Food density

• Size/thickness of food

• Initial temp. of food

Wet cooking methods use what as a heat transfer medium?

Water, water-based liquids (ex. milk) or steam

What is the best method for cooking vegetables?

• Steaming: direct contact of food with steam

• Retain color, taste, texture & nutrients

• Can use pressurized steam cookers or range top steamers with perforated basket

What is en papillote?

• Wrapping food with foil or parchment paper before baking or grilling => food cooks by steam from own juices

• Plastic wrap used for microwave

Poaching, simmering and boiling temp.

• 71-82°C

• 85-95°C

• 95-100°C

How does microwave cooking work?

Alternating + - charges cause water molecules in food to align => rub against each other (vibrate) => heat & cook

What are microwaves mostly used for?

• Defrosting

• Reheating

• Cooking

What materials are safe to use in microwave?

• Glass

• Ceramic cookware

• Plastic (microwave safe)

What materials are not safe to use in microwave?

• Foam trays

• Plastic wraps

• Aluminum (metals): reflects rays back to generator => destroy it

How to get rid of cold spots?

Stop microwave, stir, put back in (to redistribute heat)

What is used as a medium for dry heat cooking?

Any non-water liquid (ex. oil)

Equation for % fat absorption

% = [(final weight - initial weight)/inital weight] x 100

Which is faster: boiling or steaming? Why?

Boiling; convection is faster

How does cooking time affect outcome of boiled eggs?

More time => more coagulation of proteins => more tough

Explain the difference between poaching, simmering and boiling bubbles

• Poaching: small bubbles on bottom of pot

• Simmering: bubbles reach surface, but barely break it

• Boiling: steam, bubbles break surface

Which cooking method has more water loss: frying or roasting

Frying

Overall sensory difference between wet & dry cooking methods

• Wet: less color development, softer foods

• Dry: more browning, rougher texture foods