Home Economics Department
Courses
Study Guides
Homework
Textiles
Extra-Curricular Activities
Calendar
Recipes
Glow
Study Guide

National 5 Prelim Revision Guide

National 5 Health and Food Technology
Revision Notes:

Study resources can be bought for this subject through Amazon or any book shop that sells study guides

Nutrients: 5 main nutrients
Macronutrients (required in a large amount) – Protein
- Fat
- Carbohydrates
Micronutrients (required in smaller amounts) – Vitamins
- Minerals
You need to know the function of each of these/ food sources and what benefit or consequence they have in the body.
Remember:
* Fat- soluble vitamins – A, D, E and K
* Water - soluble Vitamins – B and C
* Antioxidant vitamins – A, C and E
* Minerals – Iron, Calcium, Phosphorus, Sodium and Fluoride

Product Development steps: these are also in your jotters

Concept Generation

“The thinking stage”
* Development of new ideas
* Identify any gaps in the market
* Identifying changes that would be made to
existing products.
*Cost, portion size, flavour, appearance,
texture and preparation are all considered at
this point.

Concept Screening

“Time to consider those ideas”
* Analysis of all ideas from the thinking stage
and prioritising them.
* Developing a specification
* Discarding any of the ideas that might be
costly.
* Taking forward the best ideas to the next
stage.

Prototype Production

“Time to make samples of a possible product”
* Making up examples or specimens of what
the product will look like.
* Ensuring the product will meet the needs of
the target group.
* Make any changes, if required, to the
prototype.

Product Testing

“Trial the initial ideas”
* Trialling the prototypes with a range of
consumers
* Using the opinions gained to either eliminate
or make refinements to the product.

First production run

“Time to rest the product with the consumer”
* The new product is produced for the first time as a full production run so the item can be assessed.
* Quality- assurance team tests the production run for quality and standard of the product.

Marketing Plan

“Time to get ready to launch the product”
*An advertising campaign is developed to
promote the product.
*Decisions made on where the product will be
sold.
* Promotional activities decided
* Packaging finalised and selling price agreed.

Product Launch

“Time to get it on the shelves”
* This is an important stage as the product is
now on sale.
* Market monitoring – the product is finally
launched into the national marketplace and
sale figures are checked very carefully.

Disassembly of products:
To disassemble means to take something apart.

Manufactures use disassembly to:

* Assess an existing product, especially if there has been a drop in sales or they
   wish to product a new or improved version of it.
* Ensure quality and that the product remains at its best during storage,
   purchase and use.
* Find out more information about how a foods product has been designed.
* Investigate how the proportion and variety of ingredients will affect the cost
   and nutritional value of the product.

Sensory Testing:
Why manufactures use sensory testing?
* The acceptability to the consumer of a food when developing a new product
* How it compares against a competitors product
* The shelf life through testing of the product at various recommended storage
points.
* What makes a product popular
* How to reduce the cost without affecting the flavour.

Functional Properties of Ingredients:
Function property of Flour


Gelatinisation

Occurs when a liquid is thickened by heating it with a starch. As the mixture is heated the starch molecules absorb the liquid and then swell to five times their size and burst, thickening the liquid.
The thickness of the end product will depend on the amount of flour used.

 

Dextrinisation

Occurs when foods containing flour are cooked using dry heat. The starch in the flour will change to dextrin, causing the food to turn brown.

Fermentation

Occurs when yeast produces carbon dioxide and alcohol.
Flour becomes the food that yeast requires in bread making. The natural sugars present in the flour are fermented by the yeast when left in warmth, then carbon dioxide and alcohol are produced, raising the dough.

Functional Properties of Fat


Shortening

When fat (butter and margarine) is rubbed into flour. The fat coats the flour, preventing the flour from absorbing water. This stops the dough become elastic and gives a short crumbly texture.

Aeration

When fat is creamed or rubbed in, air can become trapped, causing foods to rise.

Creaming – When butter or margarine and castor sugar are creamed together with either an electric whisk or wooden spoon, the mixture will contain tiny bubbles of air.

Rubbing in – When fat is rubbed into flour and the hands are raised. Air is trapped at the mixture falls back into the bowl.

Glazing

When fat is added to cooked vegetables it will melt, giving a shiny glazed finish.
When fat is added to sauces it will help make the sauce shine. Lack of fat will give sauces a dull finish.

Functional Properties of Eggs


Aeration

When egg white is beaten it traps air and forms foam, making spongers lighter.
This is due to the protein in the eggs stretching and trapping air bubbles to make a foam.
Eggs hold air in cakes and act as a raising agent. 

Emulsifying

Egg yolk contains a substance which acts as an emulsifier. This is used to prevent mixtures of oil and other liquids from separating.

Coagulation

When eggs are heated they change from a fluid state to a more solid stage.
Coagulation thickens fillings and quiches/
When eggs are mixed into a liquid and then heated, coagulation makes the mixture thicken.

Binding

The egg protein coagulates when heated and bind or hold combinations of ingredients together.

Eggs can also give a golden brown colour and add more flavour to products.

Functional properties of sugar


Crystallisation

Sugar dissolves in the water. When sugar and water are boiled, the water is driven off, the concentration becomes greater and eventually a thick sticky syrup is formed. This sets into very fine crystals on colling.

Caramelisation

Sugar helps to colour products, such as the top of cakes, by caramelising in the heat of the oven. When sugar is heated in a liquid or when used as a topping, it begins to caramelise and turn brown due to the heat.

Aeration and Flavour

Sugar also traps air when it is creamed with fat, making the end result lighter in texture. It also helps the yeast to rise in bread making.

Changing the proportion of ingredients will affect the finished product. This is an important factor to consider in food product development, especially if food manufactures are trying to reduce fat and sugar for health reasons.


Ingredient

Effect of an increase in a recipe

Effect of a reduction in a recipe

Fat

*Increases flavour
* Colour will darken
* Cakes – will be softer and
greasier
* Scones – will be more cake like
* Pastry – greasy, more crumbly
* Sauces – will taste fatty

* Less flavour
* Colour will be paler
* baked goods will not last as
long
* Scones – will be harder
* Pastry – will be harder
* Sauces- will not have a shiny
appearance

 

Sugar

 

* Colour will be darker
* Increased sweetness
* Will need to cook foods for  
longer
* Scones – will be speckled
* Sauces – will be thin and runny
*cakes – will have hard sugary
crust
* Fruit will sink to the bottom
* Cake – will sink in the middle

 

* Colour will be paler
* Lack of flavour
* Cakes – will not rise as much

 

 

Liquids

 

* Top of the cake will crack
* Fruit will sink to the bottom of a
cake
* Hard pastry
* Bread dough – too sticky
* Scone dough- will be too soft
and scones will not keep their
shape when cooked.

 

* Cakes – will be dry
* Scones – will not rise as well
* Pastry- will be crumbly and
difficult to roll out
* Bread – will not rise as well
and will be heavy.

Top Tips:

  • In the exam you may be given examples of food products that have not worked out as expected.
    For example: A scone that is too hard.
    Use this information on above table to help you explain why that has happened.

  • Remember: Each ingredient may have more than one function within a recipe.

  • Be able to explain how the functional properties of each ingredient may affect different food products.
    For example: By putting too much flour in a sauce it will become very thick.