Chapter 3.3 Functional roles and interaction of food ingredients in food system
1. Lipid
> Whereas untempered chocolate would have Beta fat crystals, coarse undesirable texture and also blooming.
4) Bloom is a granular-appearing, discoloured area on the surface of the chocolate. The result of melting of less stable crystals and recrystallization as β crystals on the surface.
1. Emulsion ingredient
Emulsion = water + fat + emulsifier (it can either be in oil in water or water in oil depending on dispersion medium and phase)
Emulsion system can work with the presence of any of the 3 components stated above. The formula for emulsion must be balanced and must not reach its saturation level.
2. Heat transfer
1) Lipids are non-polar organic compounds that are composed of carbon, hydrogen & small amount of oxygen.
2)There are 4 forms of fat crystals:- (fat crystals determine the properties such as consistency, stability against oiling-out and emulsion stability.)
- Alpha - extremely fine and unstable
- Beta prime - very find and reasonably stable
- Intermediate - slightly coarse
- Beta - extremely coarse & undesirable fat crystal
3)Tempering of Chocolate
> Tempering is a process of heating and cooling chocolate to a specific temperatures.
> complete melting at 50-degree Celsius >cooling to 32-degree Celsius. rewarming to 29-31 degree Celsius in order to convert any unstable crystal.
Chocolate must be tempered properly to achieve a beta prime fat crystal:
Chocolate must be tempered properly to achieve a beta prime fat crystal:
- to prevent blooming
- to have a smooth consistency
- to have a glossy appearance
- able to contract in the mould
- resistant to melting
> Whereas untempered chocolate would have Beta fat crystals, coarse undesirable texture and also blooming.
4) Bloom is a granular-appearing, discoloured area on the surface of the chocolate. The result of melting of less stable crystals and recrystallization as β crystals on the surface.
>There are 2 types of blooming:-
a) fat blooming
a) fat blooming
- Dull and covered with grey film
- The factor affecting fat blooming is due to incorrect tempering temperature, humidity, temperature fluctuation and insufficient stirring.
- Sandy and gritty texture
- The factor affecting fat blooming is due to storage in damp conditions.
1. Emulsion ingredient
Emulsion = water + fat + emulsifier (it can either be in oil in water or water in oil depending on dispersion medium and phase)
Emulsion system can work with the presence of any of the 3 components stated above. The formula for emulsion must be balanced and must not reach its saturation level.
2. Heat transfer
Flow of heat transfer:-(temperature for deep frying-190-195 degree Celsius)
Moisture transfer > Fat transfer > Crust formation > Interior cooking
Examples of heat transfer:
>French fries evaporates water quickly into cooking medium > then it forms browning on the crust> water beneath the french fries acts as conductive heat into the fries > finally starch gelatinization occurred.
The amount of fat absorbed depends on several factors:
>Frying temperature, duration and product shape
>Composition (moisture, porosity)
>Pre-frying treatments
>Surface treatment
*Functional role of Shortening power : its ability of fat to cover large surface area to minimise the contact between water and gluten during mixing of batter and dough.
*How?> fat will separate the flours starch and protein that inhibit the formation of gluten.
During baking, the fats will melt leaving little air pockets and steam collected will pushes upwards against the upper surface of resulting cell while increasing the volume. The gluten in the pastry will denature during baking while locking the cell from extending position. Thus, causes flakiness texture.
Moisture transfer > Fat transfer > Crust formation > Interior cooking
Examples of heat transfer:
>French fries evaporates water quickly into cooking medium > then it forms browning on the crust> water beneath the french fries acts as conductive heat into the fries > finally starch gelatinization occurred.
The amount of fat absorbed depends on several factors:
>Frying temperature, duration and product shape
>Composition (moisture, porosity)
>Pre-frying treatments
>Surface treatment
*Functional role of Shortening power : its ability of fat to cover large surface area to minimise the contact between water and gluten during mixing of batter and dough.
*How?> fat will separate the flours starch and protein that inhibit the formation of gluten.
During baking, the fats will melt leaving little air pockets and steam collected will pushes upwards against the upper surface of resulting cell while increasing the volume. The gluten in the pastry will denature during baking while locking the cell from extending position. Thus, causes flakiness texture.
3. Plasticity
Works as a plasticizer/ plasticizing agent. -various substances are added to plastics or other materials to keep them soft or pliable.
Works as a plasticizer/ plasticizing agent. -various substances are added to plastics or other materials to keep them soft or pliable.
>Example : glycerin, glycerol, castor oil
4. Fat replacer
A fat replacer is used to imitate the texture of fats. It contribute bulk, creaminess, thickening and stability to reduced fat or fat-free food. It is also less in calories compared to normal fats.
>There are 3 types of fat replacer:-
>There are 3 types of fat replacer:-
- Carbohydrate based(maltodextrins, xanthan gum)
- Protein based ( whey protein, egg protein, soy / corn)
- Fat based (olestra, olean, salatrim)
*Carbohydrate/protein based and fat replacer cannot heat transfer, no shortening power and no plasticity.
*however butter and fat based fat substitudes can.
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