FLOUR MIXTURE
WEEK 1
CLASS: SS 2
SUBJECT: FOOD AND NUTRITION
TOPIC: FLOUR MIXTURE
CONTENT:
(a) Types of flour in cookery – (i) whole wheat flour (ii) all-purpose flour (iii) instant blending flour etc.
(b) All purpose flour.
Sub-Topic 1: TYPES OF FLOUR IN COOKERY
The term flour refers to the powder derived from ground cereals such as wheat, cassava, corn, sorghum, yam, plantain, rice, cocoyam etc
Wheat flour: wheat is usually milled into flour before being prepared as food. Wheat flour includes: whole wheat flour, all-purpose flour, instant blending flour, self- raising flour, cake flour, pastry flour, hard wheat flour, soft wheat flour and composite flour.
Types Qualities
1. Whole wheat flour i. Contains all the natural constituents of wheat unaltered
ii. High fat content
iii. prone to rancidity
iv. Cannot stand long period of storage
2. All purpose flour i. Intermediate to bread and cake flour for all cookery purposes
ii. granular when rubbed between the fingers.
3. Instant blending flour i. Granular texture of uniform particle size.
ii. Dust free, disperses quickly in cold water.
iii. Free –flouring, dust not require pre-sifting
4. Soft wheat flour i. has soft talcum- like powder feel.
ii. Not granular
iii good for cakes, pastries, cookies and crackers
5. Composite flour i. Mixtures of two or more flours in specific ratio.
Ii used in baking.
Non wheat flour: These are produced from other foods apart from wheat, such as corn, rice, sorghum, millet, cassava, yam, plantain, beans, etc. They are used in the powder or grain form. They can also be used in the production of pastries, puddings, cakes, etc either in whole or in combination with wheat flour.
Sub-Topic 2: Raising agents:
(i) Air
(ii) Baking powder
(iii) Yeast
(iv) Palm wine
(v) Steam
(vi) Over ripe bananas etc
Raising or leavening agents are substances that produce gas in flour mixture which cause them to rise and become lighter, bigger, softer in texture and porous after cooking. The use of raising agent is based on the principle that hot air rises and expands. There are different varieties of raising agents.
(1) AIR
Sometimes, enough air may be incorporated by mechanical mixing to produce sufficient aeration during baking. This can be achieved by beating the flour mixture until enough air is incorporated into the mixture. When the mixture is baked, the incorporated air expands and then causes the product to rise. Air incorporated into egg white by beating, is used as a raising agent for omelettes, sponge cakes etc.
(2) BAKING POWDER
Baking powder is a mixture of an acid and an alkali i.e. cream of tartar or tartaric acid and sodium bicarbonate or bicarbonate of some starchy ingredients such as rice flour or corn flour. Sodium bicarbonate is the gas from the bicarbonate and the flour acts as an inert filter to absorb moisture. A typical baking powder contains 20% sodium bicarbonate, 40% acid material and 20% flour. If tartaric acid is used instead of cream of tartar, use same quantity of bicarbonate and tartaric acid. This is because the strength of tartaric acid is double that of cream of tartar. After mixing these three ingredients, store in an air-tight container. When the acid and alkali in the baking powder react during cooking, they give off carbon (iv) oxide, which is responsible for the rising of the product.
(3) YEAST
The scientific name for yeast is Saccharomyces cerevisiae. It is made up of large number of minute cells. When kept cool and dry, the cells are inactive. They grow rapidly when come in contact with warmth, moisture and little sugar, giving off carbon (iv oxide which works through the dough, making it light. Extreme heat kills yeast and it can have no further activity. Cold retards or hinders its action, but does not kill it. Apart from the carbon dioxide produced, yeast also provides alcohol which is lost during cooking.
(4) PALM WINE
Fresh palm wine is often used for commercial bread production because it contains yeast and it is economical. Palm wine is often used for large scale bread production because it is more economical than yeast. Too much cold, heat and sugar are detrimental to the action of palm wine because of the yeast it contains.
(5) STEAM
This is an effective raising agent. Steam from boiling water can act as a raising agent because it occupies is more than that of the water that produced it. Steam is used as a raising agent in the production of pop-over and cream puffs. Apart from used on its own, steam contributes to the aeration of baked products in which other raising agents are used.
(6) OVER RIPE BANANAS
At times, over ripe bananas may be used for large scale bread production. Over ripe bananas are used to produce a raising agent with the same characteristic as yeast or palm wine. The over ripe bananas are left to ferment before they are used raising a agent.
Sub-Topic 3: practical on the types of flour
EVALUATION
1. Explain the concept of yeast as a leavening agent.
2. Describe how baking powder as a raising agent works in flour mixture.
3. Describe how steam works in flour mixtures as a raising agent.
4. Give three characteristics of instant blending flour.
5. Enumerate the types of wheat flour
6. Discuss the basic method of preparing flour standard measurement in flour mixtures.
7. Discuss the use of local flour mixture in cookery.
OBJECTIVE TEST
1. _________ is an example of raising agent. (a) baking powder (b) garri (c) powder
2. Raising or leavening agents re substances that produce ________ in flour. (a) CO2 (b)carbon (c) gas
3. ___________ is not a raising agent. (a) yeast (b) steam (c) air (d) water
4. Baking powder is a mixture of ________ and _______.
5. Whole wheat flour is also known as ___________.
6. ___________ is a quality of whole wheat flour
7. __________ is not an example of flour except. (a) poundo flour (b) all purpose flour (c) whole wheat flour
8. Which of these is the fat finely shredded into the flour? (a) short crust pastry (b)flan pastry (c) suet crust pastry (d) rough puff pastry
9. Which of these flour products is produced using yeast as a raising agent? (a) cake (b) scone (c) bread (d) pastry
10. Which of these is a condition needed by yeast to become active? (a) warmth, moisture (b) moisture, pepper (c) fat, time (d) salt, vanilla
11. When a cake is heavy, the following will be the reasons: i when the mixture is fluffy ii. Too little raising agent iii. Over mixing of flour iv. Too hot an oven
(a) i, ii and iv only (b) i, iii and iv only (c) i, ii, and iii only (d) ii, iii, and iv only
12. Which of the following raising agents is used in an omelette? (a) steam (b) air (c) baking powder (d) bicarbonate of soda
WEEKEND ASSIGNMENT
Read Evans food and nutrition for senior secondary school book 2 by F.A. Bakare et al page (103 – 104)
PRE-READING ASSIGNMENT
– Read about condiments and seasoning (uses in cookery)
REFERENCE TEXT
1. Evans food and nutrition for senior secondary school book 2 by F. A. Bakare et al; Evans Brothers Nigeria Limited.
2. Exam Focus foods and nutrition for WASSCE and SSCE by J.O. Olusanya et al. University Press plc.