Question

C. Discuss how different food preparation techniques affect the nutritional value of foods. Example: How would a battered, fried chicken breast differ in nutrient composition compared to baking a chicken breast? Would boiling broccoli (versus eating it raw) change the nutrients it contains?

Answer 1

Eating nutritious foods can improve your health and energy levels.

Different food preparation techniques:

Cooking food improves digestion and increases the absorption of many nutrients.

For example, the protein in cooked eggs is 180% more digestible than that of raw eggs.

However, some cooking methods reduce several key nutrients.

The following nutrients are often reduced during cooking:

• water-soluble vitamins: vitamin C and the B vitamins — thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), folic acid (B9), and cobalamin (B12)
• fat-soluble vitamins: vitamins A, D, E, and K
• minerals: primarily potassium, magnesium, sodium, and calcium

Boiling, simmering, and poaching:

  These techniques differ by water temperature:

• poaching: less than 180°F (82°C)
• simmering: 185–200°F (85–93°C)
• boiling: 212°F (100°C)

Vegetables are generally a great source of vitamin C, but a large amount of it is lost when they’re cooked in water.

While water-based cooking methods cause the greatest losses of water-soluble vitamins, they have very little effect on omega-3 fats.

Grilling and broiling:

Grilling and broiling are similar methods of cooking with dry heat.

Grilling and broiling provide great flavor but also reduce levels of B vitamins. Also, grilling generates potentially cancer-causing substances.

Microwaving:

Microwaving is a safe cooking method that preserves most nutrients due to short cooking times.

Studies have found that microwaving is the best method for retaining the antioxidant activity of garlic and mushrooms.

Meanwhile, about 20–30% of the vitamin C in green vegetables is lost during microwaving, which is less than most cooking methods.

Roasting and baking:

Roasting and baking refer to cooking food in an oven with dry heat.

Roasting or baking does not have a significant effect on most vitamins and minerals, except for B vitamins.

Sauteing and stir-frying:

With sautéing and stir-frying, food is cooked in a saucepan over medium to high heat in a small amount of oil or butter.

Sauteing and stir-frying improve the absorption of fat-soluble vitamins and some plant compounds, but they decrease the amount of vitamin C in vegetables.

Frying:

Frying involves cooking food in a large amount of fat — usually oil — at a high temperature. The food is often coated with batter or bread crumbs.

The frying makes food taste delicious, and it can provide some benefits when healthy oils are used. It's best to avoid frying fatty fish and minimize the frying time of other foods.

Steaming:

Steaming is one of the best cooking methods for preserving nutrients, including water-soluble vitamins, which are sensitive to heat and water.

Steaming is one of the best cooking methods for preserving nutrients, including water-soluble vitamins.

1. Broccoli frequently earns a top spot on "superfoods" lists. This is partly because it delivers a healthy dose of sulforaphane, a compound thought to thwart cancer by helping to stimulate the body's detoxifying enzymes. According to recent research in the Journal of Agricultural and Food Chemistry, raw broccoli provides significantly more of this beneficial nutrient than cooked.

Those who ate the raw broccoli absorbed sulforaphane faster and in higher amounts compared to those who ate it cooked.

2. The advantage of roasted over fried chicken is less fat, particularly at places that use rotisserie cooking, a method that drains off fat. "In fried foods, the flesh of the meat absorbs the oil and makes it a lot higher in calories and fat.