- In what way is the protein in a raw egg the same as that in a cooked egg?
- In addition to emulsifying greasy materials, what other useful function might be served by a detergent used to wash dishes?
The Correct Answer and Explanation is :
1. Protein in a Raw Egg vs. Cooked Egg
The protein in a raw egg is chemically the same as the protein in a cooked egg. However, the major difference lies in the protein structure due to the process of cooking.
In a raw egg, proteins are in their natural, folded form, which is called “native conformation.” These proteins are relatively insoluble in water and are not easily digestible. When the egg is cooked, the heat denatures these proteins, which means they unravel from their tightly folded structure. This process is known as denaturation, and it alters the protein’s three-dimensional shape. Denatured proteins become more soluble in water, which increases their digestibility. Despite this change in structure, the amino acids that make up the proteins remain unchanged, and their nutritional value stays the same.
So, while the protein content and the types of proteins in both raw and cooked eggs remain identical, the cooking process changes the physical form of the protein, making it easier for the body to digest and absorb.
2. Function of Detergent in Washing Dishes
Detergents are primarily used in dishwashing to emulsify and break down greasy substances that are difficult to wash away with water alone. However, detergents serve other useful functions as well, which make them effective at cleaning a variety of surfaces, including dishes.
Key Functions of Detergents:
- Surface Tension Reduction: Detergents lower the surface tension of water, which allows the water to spread more evenly and easily over the surface of the dish. This makes it easier for water to penetrate and break up greasy residues and food particles.
- Dispersion of Dirt and Oil: Detergents contain surfactants, which have hydrophilic (water-attracting) and hydrophobic (water-repelling) ends. The hydrophobic part of the detergent molecule binds to oil and grease, while the hydrophilic part binds to water. This creates micelles, small clusters of detergent molecules, which trap the grease and oil inside. These micelles are then suspended in water and rinsed away, effectively cleaning the surface.
- Foaming Action: Although the foaming aspect is not directly involved in cleaning, it can help by creating a visually noticeable lather that can help scrub away dirt and grease. Additionally, the foam can make it easier for the detergent to be distributed across large surfaces, like pots and pans.
- Antibacterial Properties: Some detergents are formulated with antibacterial agents, which help to eliminate harmful microorganisms that could remain on dishes after washing. This provides an added layer of hygiene during the cleaning process.
Thus, the detergent is more than just an emulsifier; it acts to lower surface tension, disperse oils, and, in some cases, provide antibacterial properties to ensure effective cleaning.