COMMODITIES

A. SHORTENINGS

Shortenings mean the fat and oils which are used for tenderizing the food products. They consist of fatty acids & glycerol, also known as triglycerides. Fats are solid at room temperature and melt when heated. Those used in cooking are lard (pig’s kidney region fat), suet (beef, mutton or any other animal fat), butter, margarine and hydrogenated fats. Oils are liquid at room temperature but tend to solidify at cold temperature. Commonly used oils are coconut oil, peanut oil, mustard oil, sunflower oil etc.

Composition

These are composed of fatty acids and glycerol. Glycerol is a syrupy liquid which is heavier than water & it is sweet in taste. Specific density of glycerol is higher than water whereas shortenings have specific density less than water. Specific density is the ratio of weight of 01 gm of substance and equal weight of water.

Shortening are insoluble in water and process of blending of fats & water is called emulsification.

Process for fats / oils

1.   Purification: crude oil contains pungent flavour and taste which makes it unsuitable for the use. For removing this, oil is mixed with caustic soda, which combines with free floating fatty acids to form crude soap. This crude soap is separated from the oil by centrifugal force.

2.   Bleaching: it is done to remove the yellow pigment present in the oil. It is carried out by passing the oil through a filter which allows only a light coloured oil to pass through it. With this also goes off remaining undesirable smell. The refined oil after the bleaching is treated in several ways depending upon the product requirement.

3.   Hydrogenation: in this, liquid is changed into solid form, with this process, the melting point of fat also increase. The degree of hardness of fat depends upon the degree of hydrogenation. Hydrogenation is the process of addition of hydrogen to the free floating carbon bonds in the fatty acids.

4.   Deodorisation: this removes many substances which have got the objectionable odours.

Rendering of fat

Animal fat is heated and melted and this renders fat from fatty tissues. Tallow, suet and lard are usually rendered and used for cooking. The fat is cut into small pieces in a pan and put in the oven or on slow fire, until the fat melts, and there are crisp brown pieces of tissues left. This should be strained through a muslin cloth.

Clarification of fat

Used fat should be clarified and then re use. Strain the used fat and then mix with double the quantity of water in a pan and bring it to the boil. Strain again, cool & place it in a refrigerator. The fat will solidify and float on top. Lift the cake of fat, turn it upside down and scrape off the foreign particles that have collected. Heat the fat on slow fire, till the water evaporates & strain.

Types of fats or oils

1.     Butter.

2.     Ghee: it is clarified butter. It is prepared by heating the butter till the milk solids get separated and hence can be taken out easily. Ghee does not contain protein & rest of food value is similar to that of butter. Ghee is also not good for baker’s use, as of bigger crystals than butter, so it only gives flavour to the product and does not help in increasing volume and grain.

3.     Margarine: it is produced from milk and a blend of vegetable oils emulsified with lecithin. Also contains flavouring, salt, colourings & vitamins a & d. This mixture is strongly agitated to form an emulsion. The mixture is passed through coolers and crystallising units. This is generally used as substitution of butter and comes in various grades such as block (hard/ semi hard) and soft (butter substitute). Semi hard margarine is used for pastry & cake making.

4.     Lard: this is rendered from the kidney region of the pig & has 100% fat content. It is firm, white in colour and is used for deep frying as well as shallow frying.  

5.     Suet: it is hard solid fat dispersed around the kidney region of animals. Beef suet is best which is used to make suet paste and minced meat and it is white coloured.

6.     Tallow: it is the fat which is rendered from the beef caracas. It is pale yellow in colour.

7.     Vegetable fats: these are shortenings which are liquid at room temperature. It is obtained from sunflower, soyabean, almonds, sesame seeds, cotton seeds, olive, groundnuts, hazelnuts etc. These have very high fat content & are good sources of energy. Olive oil is considered as the best owing to its flavour. Better oils are almost without flavour, odour & colour.

8.     Herbal oils are obtained by adding chopped herbs like thyme, tarragon, basil etc. To olive oil pouring into the jars and leaving it refrigerated for about 3 weeks. Finally the oil can be strained or bottled.

Smoke point: it is the stage in heating process at which the smoke starts coming out of the fats. The greater the presence of free flowing fatty acids, the lower the smoking point. As far as baker is concerned, margarine has the highest melting point which results in high smoke point followed by ghee & butter.

Storage of fats and oils

·         Oils are at their best if kept at 70-80º c.

·         Must not be stored near strong smelling food products & spices.

·         Shortenings containers must be kept closed.

·         Must be free from moisture otherwise splatter oil when heated.

  

Roles of shortening / Uses of Shortening

1.     They increase nutritive value of foods.

2.     They improve flavour of dishes.

3.     They help in retaining moisture and it’s this property prevent the bread and cakes from drying up.

4.     They help in attaining a good volume due to creaming property.

5.     A fat helps in tendering various products.

6.     They improve the appearance of the dish.

7.     Satiety value.

8.     Preserve foods.

9.     Fats give elasticity to dough.

RAISING AGENT LEAVENING AGENTS

Leavening is the production or incorporation of gases in a baked product to increase Volume and to produce shape and texture. These gases must be retained in the product until the structure is set enough (by the coagulation of gluten and egg protein) to hold its shape. Exact measurement of leavening agents is important because small changes can produce major defects in baked products.

1.   Yeast

Fermentation is the process by which yeast acts on carbohydrates and changes them into carbon dioxide gas and alcohol. This release of gas produces the leavening action in Yeast products. The alcohol evaporates completely during and immediately after baking.

Yeast is a microscopic plant. As a living organism, it is sensitive to temperatures.

·         34°f (1°c) inactive; storage temperature.

·         60° to 70°f (15° to 20°c) slow action.

·         70° to 90°f (20° to 32°c) best growth; proofing temperature for bread dough’s.

·         Above 100°f (38°c) reaction slows.

·         140°f (60°c) yeast is killed.

Yeast is available in three forms:

1. Fresh yeast, also called compressed yeast, is moist and perishable and is preferred By professional bakers. It is usually purchased in 1-lb (450-g) cakes.

2. Active dry yeast is a dry, granular form of yeast. Active dry yeast must be rehydrated in 4 times its weight of warm water [about 110°f (43°c)] before use. When using active dry yeast in a bread formula, use part of the water in the formula to dissolve the yeast. Do not add additional water.

3. Instant dry yeast is also a dry granular form of yeast, but it does not have to be dissolved in water before use. It can be added in its dry form because it absorbs Water much more quickly than regular dry yeast. It also produces more gas than Regular dry yeast, so less of it is needed. Instant dry yeast is sometimes called rapid rise Or quick-rise yeast.

2.   Chemical raising agent

A.   Baking soda

Baking soda is the chemical sodium bicarbonate. If moisture and an acid are present, Soda releases carbon dioxide gas, which leavens the product. Heat is not necessary for the reaction (although the gas is released faster at higher Temperatures).for this reason, products leavened with soda must be baked at once, or the gases will escape and leavening power will be lost. Acids that react with soda in a batter include honey, molasses, buttermilk, fruits, Cocoa, and chocolate. Sometimes cream of tartar is used for the acid. The amount of Soda used in a formula is generally the amount needed to balance the acid. If more leavening Power is needed, baking powder, not more soda, is used.

B.   Baking powder

Baking powders are mixtures of baking soda plus an acid to react with it. Because baking powders do not depend on acid ingredients for their leavening Power in a formula, they are more versatile.

C.   Baking ammonia

Baking ammonia is the chemical ammonium carbonate. It decomposes during baking to Form carbon dioxide gas and ammonia gas. only heat and moisture are necessary for it to work. No acids are needed. Because it decomposes completely, it leaves no residue that can affect flavor. However, It can be used only in small products, like cookies, which allow the ammonia gas to Be completely driven off. Baking ammonia releases gases quickly, so it is sometimes used in products like Cream puffs where rapid leavening is desired.

3.   Air

Air is incorporated into a batter primarily by two methods, creaming and foaming. This Air expands during baking and leavens the product.

1. Creaming is the process of beating fat and sugar together to incorporate air. It is an important technique in cake and cookie making. Some pound cakes and cookies Are leavened almost entirely by this method.

2. Foaming is the process of beating eggs, with or without sugar, to incorporate air. Foams made with whole eggs are used to leaven sponge cakes, while angel food Cakes, meringues, and soufflés are leavened with egg white foams.

4.   Steam

When water turns to steam, it expands to 1,600 times its original volume. Because all baked products contain some moisture, steam is an important leavening agent. Puff pastry, cream puffs, popovers, and pie crusts use steam as their major or only Leavening agent. If the starting baking temperature for these products is high, steam is produced rapidly and leavening is greatest.

5.   Lamination it acts as a raising agent in dhokla, puri, puff etc. Steam formed by the heat helps to puff up as liquid & flour are present in equal quantities, when heated they expand in volume. Fat when comes under the influence of heat expands & liberates the water vapours & gluten in the dough helps in the expansion, examples puff & flaky pastries. 

C. SUGARS

Sugars or sweetening agents are used for the following purposes in baking:

• To add sweetness and flavour.

• To create tenderness and fineness of texture by weakening the gluten structure.

• To give crust colour.

• To increase keeping qualities by retaining moisture.

• To act as creaming agents with fats.

We customarily use the term sugar for regular refined sugars derived from sugar Cane or beets. The chemical name for these sugars is sucrose. However, other sugars of different chemical structure are also used in the bakeshop. The following are the more important sugars.

A.   Granulated sugar: Regular granulated, also called fine granulated or table sugar, is the most familiar And the most commonly used. Very fine and ultrafine sugars are finer than regular granulated. They are prized for making cakes and cookies because they make a more uniform batter and can support higher quantities of fat. Sanding sugars are coarser and are used for coating doughnuts, cakes, and other Products.

B.   Confectioners’ or powdered sugars: Confectioners’ sugars are ground to a fine powder and mixed with a small Amount of starch to prevent caking. They are classified by coarseness or fineness. 10x is the finest sugar. It gives the smoothest textures in icings. 6x is the standard confectioners’ sugar. It is used in icings, toppings, and cream Fillings. Coarser types (4x and xx) are used for dusting or for any purposes for which 6x And 10x are too fine.

C.   Molasses and brown sugar: Molasses is concentrated sugar cane juice. Sulphured molasses is a by-product of sugar Refining. it is the product that remains after most of the sugar has been extracted from Cane juice. Unsulfured molasses is not a by-product but a specially manufactured sugar Product. Its taste is less bitter than that of sulphured molasses. Molasses contains large amounts of sucrose, plus other sugars, acids, and impurities. Brown sugar is mostly sucrose, but it also contains varying amounts of molasses and other impurities. the darker grades contain more molasses. Because molasses and brown sugar contain acids, they can be used with baking Soda to provide leavening Molasses retains moisture in baked goods and so prolongs freshness. However, Crisp cookies made with molasses quickly become soft for the same reason.

D.  Corn syrup: Corn syrup is a liquid sweetener consisting mainly of a sugar called glucose. It is made by converting cornstarch into simpler sugar compounds by the use of enzymes. Corn syrup aids in retaining moisture and is used in some icings and in candy Making.

E.   Glucose syrup: While corn syrup contains other sugars in addition to glucose, pure glucose syrup is also available. It resembles corn syrup but is colourless and nearly tasteless. If a recipe Calls for glucose syrup and none is available, substitute light corn syrup.

F.   Honey: Honey is natural sugar syrup consisting largely of glucose and fructose, plus other Compounds that give it flavour. Honeys vary considerably in flavour and colour, depending On their source. Flavour is the major reason for using honey, especially because it can be Expensive. Honey contains invert sugar, which means that it stays smooth and resists crystallizing. Like molasses, it contains acid, which enables it to be used with baking soda as a Leavening.

G.  Malt syrup: Malt syrup is used primarily in yeast

Degrees and stages of cooking the sugar

102oc small thread suitable for rasgullas

103oc large thread suitable for jellebis

106oc pearl suitable for gomme (white concentrate sugar syrup)

116°c soft ball suitable for marzipan

119°c ball suitable for fondant

121 °c hard ball suitable for nougat

143°c soft crack suitable for Italian meringue

156°c hard crack suitable for dipping fruit

163oc-177oc caramel suitable for caramel custard.