Velda

18

clumsy

loud

full of crap

Ingredients needed for Chocolate ice cream
1) Sunflower oil (fat),
2) milk solids non-fat,
3) stabilizer,
4) emulsifier,
5) flavouring agents,
6) colouring,
7) sweetener

FUNCTIOS OF INGREDIENTS:
Fat
- improves the mouthfeel and body of the ice cream (gives rich and smooth mouthfeel)
- good melting properties
- eg) cream, butter
Milk solids non-fat
- eg) vitamins and mineral and lactose, whey proteins
- proteins act as emulsifier and is hygroscopic and facilitates aeration (introducing air to the ice cream).
- proteins also contributes the elasticity of the ice cream
Stabilizer
- stabilizers contributes to the body and texture of the ice cream
- limit retrogradation of the ice cream during storage(inconstant temperature)
- indirectly extent the shelf life of the ice cream
- eg) gum, xanthan and gelatin
- carrageenan is a stabilizer most commonly used
Emulsifier
- helps in aeration of the ice cream
- enhances the body and texture of the ice cream (smoother)
- make sure that the proteins and fats are not separated (lowers the surface tension) and lead to coalescence affects the texture of the ice cream
- eg) lecithin
Flavouring agent
- impart flavour to the ice cream
- eg) chocolate flavour
Colouring
- impart desirable and attractive colours to the ice cream
- improves the overall appearances by making the ice cream look appealing


Composion of the ingredients in ice cream
FOR PREMIUM ICE CREAM:

Fat: 14-16 %
Milk solids non-fat: 7-8%
Sweetener: 13-17%
Stabilizer: 0-0.5%
Emulsifier: 0-0.5%
Total solids: 40-45%


Mixing of raw ingredients:
- blended together to form ice cream mixture according to the recipe.
- Heat the liquid (milk) ingredient till about 50°C.


Pasteurization:
- During batch and continuous pasteurization, pathogens would be killed. (controls bacterial count )
Eg) Listeria monocytogenes
- at 69°C for ½ hour and 80°C for 15-25sec

Homogenization:
- Force the hot ice cream mixture through small apertures thereby creating fat emulsion
- usually at the temperature of 63-77°C
- 2 stages of homogenization:
Fist stage: 2000-3000 psi gage (15.5-18.9 MPa)
2nd Stage: 500 psi gae (3.4MPa)
- prevent coalescence of fat globules  contributes to the smoothness of the ice cream & shortens the time for ageing


Ageing:
-Aging time would be approximately 4hrs. Mixture temperature  not exceed 4°C
-this temperature enable the fat to cool and crystallize and
-also increase the hygroscopic properties of milk proteins and stabilizers  result in a slight increase of the viscosity
- improve body and texture of the ice cream mixture

Freezing:
- 2 stages: whipping and freezing (essential process that contributes to the end quality of the ice cream)
Eg)mouthfeel
- Flavouring and colouring should be added prior freezing (make sure that that the ingredients are partially cooked or parsteurized before addition prevent microboial contamination)
-when the mixture pass through the freezer (Residence time) 0.4-2 min
-freezing rate: 5-27°C min-1  afterwhich the draw temperature  -6°C could be achieved
- % overrun= [(vol of ice cream produce- vol of mix used) / vol of mix used] x 100
-% overrun should not exceed 3 x and not less than 2.5x of the total solids composition to prevent loss in quality of the end product
-too muc or too little of the over run will affect the affect body and mouthfeel of the ice cream


Packaging:
-pack the ice cream into the suitable packaging material  transfer them in the hardening chamber
-should be done quickly so that the ice cream will not melt

Hardening:
- (-30°C) or lesser
-Most of the water freezes
- improve ice cream quality because small ice crystals are formed instead of big ones affects the shelf life of ice cream
- During hardening, the temperature of the freezers should be maintained at below -30 degree Celsius to retain the quality of the ice cream

Storage:
-Store the ice cream at -25 degree Celsius.
-should maintain a constant temperature
-should prevent heat shock from occurring large ice crystal form affect the quality of the ice cream