10 Role of ingredients in bread products manufacture-2: Shortening and sugar

Ms. Deepika Goswami

1.0 Shortening

According to BIS standards, “Bakery shortening” means vanaspati meant for use as a shortening or leavening agent in the manufacture of bakery products for promoting the development of the desired cellular structure in the bakery product with an accompanying increase in its tenderness and volume (IS:10634-1986).

Shortening lubricates the structure of a baked product. Lard, butter and some vegetable oils like coconut oil, corn oil, cottonseed oil, peanut oil and soybean oil are commonly used as bakery shortening. It is fat part of the mixture which holds large number of air cells incorporated during creaming.

Butter: It is considered to be the best of all baking shortenings from a flavour standpoint. It imparts desirable flavour to the finished baked products. It is widely used for specialty breads, sweet goods, cookies and pastries. It has good shortening value. Cake made with butter is generally lower in volume and has coarser grain. But it deteriorates easily by bacterial or mold action. Salt added would act as preservative but not sufficient to avoid deterioration because salt added in separated butter may not be evenly distributed, leaving some water droplets which results in bacterial infection deterioration. Oxidative deterioration results in tallowy flavour.

Lard: Fat rendered from fresh, clean, sound, fatty tissues from hogs in good health at the time of slaughter. Lard has distinctive natural flavour and odour, which is considered desirable in certain baked products primarily bread, crackers and pie crusts. It is most widely used shortenings for bread, pies, soda crackers and find extensive use in pan greasing and in cookie dough.

Role of shortening in baking

The major functions of shortening are as given below –

• To weaken or shorten the dough by weakening its gluten network, resulting in the baked product being softer and breaking easily
• To impart flavour to the baked product. For example, using butter for particular baked goods and lard for meat pie pastry.
• To act as emulsifiers for holding of liquids To improve the eating qualities of the product
• To entrap air during creaming, beating and mixing so as to obtain a batter containing numerous tiny air bubbles trapped within droplets of fat. During baking these trapped bubbles expand producing a spongy, light and airy structure of the baked product.
• To promote a desirable grain and texture
• To develop flakiness in product
• To lubricate the gluten for development of yeast-raised dough

Requirements for bakery shortening

The shortening to be used in bakery should have the following properties-

1.     Bland flavour

2.     White appearance

3.     Good plasticity

4.     Flavour and oxidative stability

As per the BIS standards the bakery shortening should conform to the standards as prescribed in the clauses 3.7 and 7.1.

S. No.	Characteristics	Requirement
1	Moisture, percent by mass, Max	0.25
2	Acid value, Max	0.5
3	Unsaponifiable matter, percent by mass, Max	2.0
4	Melting point, oC, Max	31-41
5	Refractive index at 60 oC, Min	1.4505
6	Iodine value, Max	75
7	Synthetic vitamin A, I.U., per gram, Min	25

Sugar

Sugar, also known as sucrose, has many functions as an ingredient in flour mixtures and baked products. The sugar usually used is pure sucrose as castor sugar and icing sugar. Occasionally impure forms such as golden syrup, honey and brown sugar are used to give the baking a particular flavour. It is most commonly thought of as a sweetener, but in baked goods it is also involved in several other processes.

Browning of baked products: Sugar undergoes a series of complex browning reactions above 160oC imparting the brown crust colour to many baked goods. These reactions are maillard reactions in which sugar interacts with amino acid in presence of heat, and caramelization reactions caused due to dry heating of sugar.

Yeast food: Sugar is essential for fermentation activity of yeast to produce CO2 gas which raises the dough and imparts proper volume to the bread.

Keeping quality: In non-fermented goods such as biscuits, large quantities of sugar when added, improves the keeping quality of the biscuits apart from sweetening them. Tenderizer: In cake sugar prevents the gluten formation and act as tenderizer.

Creaming: Sugar assists in creaming process with fat which helps in air incorporation.

Nutrition: Sugar act as a source of energy in the baked product.

Moisture retention: Sugar, like salt, attracts water and holds moisture in the finished product. The effect of holding water also means that excessive amounts of sugar will inhibit fermentation by keeping the water away from where it needs to be. In bread recipes with a large amount of sugar, it must be added in stages to prevent disruption in fermentation.

Types of sugar used in bakery products

Medium granulated sugar: Coarse crystal sugar used in products in which very coarse grain is desired. For e.g. in sand cookies, pies etc.

Sanding sugar: This sugar is the lightest coloured and is used for sparkling purpose. It has property of reflecting light which imparts sparkling appearance to the product.

Extra fine granulated sugar: This sugar dissolves readily in water or in other liquefying agents and is the most frequently used sugar in baking industry

Icing Sugar: This sugar promotes higher gloss, rapid crusting and hence used for high quality icing production.

Brown or Soft Sugar: This sugar is used in dark breads, many cookies and in devils food, spice and other dark cakes.