key term - Lactose

Definition

Lactose is a disaccharide sugar composed of two monosaccharides, glucose and galactose, linked by a glycosidic bond. It is primarily found in milk and dairy products, serving as an important source of energy for many organisms, especially during infancy. The digestion of lactose requires the enzyme lactase, which breaks it down into its constituent sugars for absorption in the body.

5 Must Know Facts For Your Next Test

1. Lactose accounts for about 2-8% of the total composition of milk, depending on the species.
2. People who are lactose intolerant have low levels of lactase, which can lead to gastrointestinal discomfort when consuming dairy products.
3. Lactose can be found in various dairy products including milk, cheese, and yogurt, but the amount varies between them.
4. In addition to its nutritional role, lactose is used in food processing and pharmaceuticals as a stabilizer and filler.
5. The fermentation of lactose by certain bacteria is essential in the production of yogurt and some cheeses, contributing to their flavor and texture.

Review Questions

• How does the structure of lactose relate to its function as a source of energy?
  • Lactose's structure as a disaccharide, consisting of glucose and galactose linked by a glycosidic bond, plays a crucial role in its function as an energy source. When digested by lactase, lactose is broken down into these monosaccharides, which can be easily absorbed into the bloodstream and utilized by the body for energy. This process illustrates how the molecular structure directly impacts the biological role of lactose in nutrition.
• Discuss the implications of lactose intolerance on dietary choices and health.
  • Lactose intolerance arises from insufficient production of lactase, leading to difficulties in digesting lactose-containing foods. This condition can significantly impact dietary choices, forcing individuals to avoid dairy products or seek lactase supplements. Moreover, this avoidance can lead to potential nutritional deficiencies, particularly in calcium and vitamin D, which are abundant in dairy. Therefore, understanding lactose intolerance is essential for making informed health and dietary decisions.
• Evaluate the role of lactose in food processing and how it affects product development within the dairy industry.
  • Lactose plays a significant role in food processing within the dairy industry due to its unique properties as a sugar. It not only serves as a source of sweetness but also contributes to texture and fermentation processes in products like yogurt and cheese. The ability of certain bacteria to ferment lactose enhances flavor profiles and influences product stability. Thus, lactose’s multifaceted role impacts product development strategies, guiding innovations in dairy processing and contributing to consumer preferences.

Related terms

Disaccharide: A carbohydrate made up of two monosaccharide units joined by a glycosidic bond.

Lactase: An enzyme produced in the small intestine that catalyzes the hydrolysis of lactose into glucose and galactose.

Galactose: A monosaccharide sugar that, along with glucose, makes up lactose.