Protein or the physical region of the protein that participates in chemical catalysis. In solution proteins also undergo variation in structure through thermal vibration and the collision with other molecules. Proteins can be informally divided into three main classes, which correlate with typical tertiary structures: globular proteins, fibrous proteins, and membrane proteins. Almost all globular proteins are soluble and many are enzymes. Fibrous proteins are often structural, such as collagen, the major component of connective tissue, or keratin, the protein component of hair and nails. Membrane proteins often serve as receptors or provide channels for polar or charged molecules to pass
Protein adsorption in the food industry in fining of wines. Protein adsorption and protein fouling can cause major problems in the food industry (particularly the dairy industry) when proteins from food adsorb to processing surfaces, such as stainless steel or plastic (e.g. polypropylene). Protein fouling is the gathering of protein aggregates on a surface. This is most common in heating processes that create a temperature gradient between the equipment and the bulk substance being heated. In protein-fouled heating equipment, adsorbed proteins can create an insulating layer between the heater and the bulk material, reducing heating efficiency. This leads to inefficient sterilization and pasteurization. Also, proteins stuck