Potential Q 2

Preserving Vitamins in Food

To maximize the nutritional value of your produce, focus on minimizing exposure to light, heat, and water:

• Cook with minimal water: Many vitamins, particularly B-complex and Vitamin C, are water-soluble and leach into cooking water. Instead of boiling, opt for steaming, microwaving, or stir-frying to retain nutrients.

• Limit heat exposure and cook time: High heat and long cooking times break down heat-sensitive vitamins. Cook vegetables until they are just tender-crisp rather than mushy.

• Store produce properly: Keep fresh produce in cool, dark places (like the refrigerator crisper drawer) to slow down the natural degradation of vitamins that occurs after harvesting. Use items as soon as possible after purchase.

Vegetarian and Vegan Diets

Adopting a plant-based diet can have significant health impacts, requiring careful planning to ensure nutritional adequacy.

Types of Vegetarians

1. Lacto-Ovo Vegetarian: Excludes meat, fish, and poultry but includes dairy products and eggs.

2. Lacto-Vegetarian: Excludes meat, fish, poultry, and eggs but includes dairy products.

3. Vegan: Excludes all animal-derived products, including meat, fish, poultry, dairy, eggs, and often honey.

Benefits and Risks

Benefits	Risks / Potential Deficiencies
Lower risk of heart disease and hypertension	Vitamin B12 deficiency: Primarily found in animal products.
Potential for lower body mass index (BMI)	Iron deficiency: Plant-based (non-heme) iron is less absorbable.
Increased fiber, antioxidant, and phytonutrient intake	Calcium & Vitamin D deficiency: Critical for bone health.
Often associated with lower cholesterol levels	Omega-3 fatty acids: Essential fats, particularly DHA/EPA.

Functions of Proteins in Humans

Proteins are the workhorses of the body, performing diverse roles:

1. Structural Support: Proteins form the building blocks of the body.

   • Example: Collagen provides structural integrity to skin, tendons, and ligaments.

2. Enzymatic Activity: Proteins act as biological catalysts to speed up chemical reactions.

   • Example: Amylase in saliva breaks down starches into sugars.

3. Transport: Proteins carry vital substances throughout the bloodstream or across cell membranes.

   • Example: Hemoglobin transports oxygen from the lungs to tissues throughout the body.

4. Defense (Immune Function): Proteins recognize and neutralize foreign invaders.

   • Example: Antibodies (immunoglobulins) identify and bind to bacteria and viruses to mark them for destruction.

5. Regulation and Signaling: Many proteins act as hormones to coordinate biological processes.

   • Example: Insulin is a protein hormone that regulates blood glucose levels.

Understanding Hydrogenation and Trans Fats

Hydrogenation is an industrial process used to convert liquid vegetable oils into solid or semi-solid fats (like margarine or shortening). During this process, hydrogen gas is bubbled through the oil under high pressure and heat, often in the presence of a metal catalyst like nickel. This adds hydrogen atoms to the unsaturated carbon-carbon double bonds in the fatty acid chains, making the fat more saturated and shelf-stable.

why hydrogenation produces trans fat

The chemical structure of natural unsaturated fats is in the "cis" configuration, where the hydrogen atoms are on the same side of the double bond, creating a "kink" in the chain that keeps the fat liquid at room temperature.

During partial hydrogenation, the high heat can cause some of these double bonds to rotate, rearranging the hydrogen atoms to opposite sides of the bond—a "trans" configuration. This makes the fatty acid chain straighter, allowing it to pack more tightly and remain solid at room temperature. The body struggles to metabolize these unnatural trans-configured bonds, leading to adverse health effects such as increased LDL ("bad") cholesterol and decreased HDL ("good") cholesterol.