ANSWER

Shortening are fats formulated from oil and base oil, often with a plasticizer and an emulsifier. In a baked product, absence in shortening causes gluten and starch particles to adhere to each other and give the sensation of hardness and toughness when chewed. However, if shortening is present, the fat breaks the continuity of protein and starch structures. This enables the lubrication of gluten particles, which produces tender and well-aerated bakery products. In frying applications, shortening allows for quick and uniformed heat transfers during cooking, and aids in the formation of a moisture barrier (Source: Hui, 2006; Ghotra et al., 2002).

Functions of Shortening

Shortening performs a number of desirable functions in bakery foods. These includes:

• Imparting tenderness

• Moister mouth feel

• Structural integrity

• Lubrication

• Air incorporation

• Heat transfer

• Extended shelf life

There are factors which determine the ability of a particular fat or oil shortening to perform one or more of the functions. These are:

• Solid Fat Content (SFC)

Solid fat content (SFC) is the percentage of shortening which is solid at various temperatures. This is required to understand the properties of the shortening at different temperatures which relates to melting qualities and flavor.

• Plasticity

The plasticity of a fat as defined operationally; the shortening is smooth, not grainy, and deforms readily when squeezed but holds its shape when set on a flat surface. Plasticity is a function of two factors: SFC and crystal structure. For most purposes, a broad plastic range is preferable as seasonal temperature changes have less effect on the ability to mix, cream, or spread the shortening during processing.

• Oxidative stability

In many applications, particularly deep-fat frying, oxidation of unsaturated fatty acids can be deleterious. In products that have a long shelf life (for example, cookies) fat oxidation leads to rancidity. The musty odors and off-flavors associated with this condition are due to volatile breakdown products (mostly aldehydes) from oxidized fat.

 

Type of Shortenings

Table 1: Application of Different Type Shortening

Type of Shortening	Type of Oil	Melting Point (˚C)	Application
All-purpose shortening	Fish oil	30 – 48	General baking and frying-Shows good baking performance and satisfactory frying quality.
	Tallow	40 – 44
	Palm oil	42 – 48
	Soybean oil	32 – 38
	Rapeseed oil (As a lower price substitute for soybean oil)	32 – 38
Cake and pastry shortening	Groundnut oil	32 – 35	Cake, pastry and biscuit-Increases plasticity of baking fats.
	Soybean oil	32 – 38
	Rapeseed oil	32 – 38
	Palm oil	32 – 38
	Fish oil	32 – 38
	Lard	35 – 38
Puff pastry shortening	Soybean oil	36 – 40	Puff pastry-Permits sufficient stretching and a stable crystal structure that prevents oiling off and softness during roll out.
	Palm oil	40 – 44
	Fish oil	36 – 40
	Tallow oil	40 – 46
Cream shortening	Fish oil	30 – 34	Icings and cream filling-Excellent aeration properties and quick melting characteristics.
	Palm oil	30 – 34

 

Table 2: Application of Different Type Shortening

Type of Shortening	Type of Oil	Melting Point (˚C)	Application
Traditional shortening	Groundnut oil	≈30	Cream filling
Pourable shortening/ fluid shortening	Soybean oil	46 – 48	Preparation of snacks and fried food-It contributes to the flavor and mouth feel of fried foods.
	Sunflower oil	46 – 48
	Palm oil	46 – 48
Dry shortening	Soybean oil	36 – 44	Dry “ready mix” products-Spray crystallized or spray-dried powdered fats.
	Palm oil	40 – 46
	Fish oil	36 – 44

(Ghotra et al., 2002; Hui, 2006; ).

 

References

Ghotra, B., Dyal, S., & Narine, S. (2002). Lipid shortenings: a review. Food Research International, 35(10), 1015-1048. https://doi.org/10.1016/s0963-9969(02)00163-1

Hui, Y. H. (2006). Handbook of Food Science, Technology and Engineering. Boca Raton: CRC Press.