CONCEPT 27: PRECOOKING MAKES VEGETABLES FIRMER

Question 1

Can almost any vegetable be roasted in a pan or oven?

Answer 1

Yes

Question 2

Whats the problem with roasting vegetables in the oven?

Answer 2

Their very high water content causes significant moisture loss when browned in the oven. This concentrates flavor but can leave you with a batch of wrinkled, dry vegetables.

Question 3

How do you get vegetables tender without moisture loss?

Answer 3

Steam them.

Question 4

Precooking is especially important for vegetables such as…

Answer 4

Potatoes, sweet potatoes, carrots, Brussels sprouts, asparagus and cauliflower; vegetables that can become firm and stay firm during cooking when exposed to short cooking times and low heat.

Question 5

Vegetables (such as Potatoes, sweet potatoes, carrots, Brussels sprouts, asparagus and cauliflower) contain an enzyme that becomes most active at what temperatures?

Answer 5

Between 120 and 160 degrees Fahrenheit.

Question 6

What is this vegetable enzyme called?

Answer 6

Pectin methyl esterase.

Question 7

What does pectin methyl esterase do?

Answer 7

Causes pectin in cell walls to more readily link with calcium ions, which are already present in the vegetables structure. This link causes pectin to become stronger, making the vegetables much less prone to breaking down.

Question 8

Though use interchangeably, are brown and caramelize the same thing?

Answer 8

No

Question 9

What is caramelization?

Answer 9

Describes the chemical reactions that take place when sugar is heated to the point that its molecules begin to break apart and generate hundreds of new flavor, cold and aroma compounds. Example: crème brûlée.

Question 10

Name three vegetables that are high in natural sugar.

Answer 10

Onions, carrots and squash.

Question 11

Describe browning.

Answer 11

The process that involves the interaction of not just sugar molecules and heat but also proteins and their breakdown products, amino acids–and is called Maillard reaction. Browning creates a tremendous number of flavors and color, but they’re not the same as caramelization because protein is involved.

Question 12

Do meats and bread benefit from caramelization or browning?

Answer 12

Browning

Question 13

Do vegetables benefit from browning or caramelization?

Answer 13

Since vegetables contain little or no protein they technically caramelize.

Question 14

What do pectin strands and calcium bond look like?

Answer 14

Pectin is like a wire fence, calcium ions are dots at each point.

Question 15

What does a gentle start and hot finish do for vegetables?

Answer 15

Vegetable cells maintain a strong pectin network due to the work of enzyme pectin methyl esterase, which causes pectin to link with calcium ions.

Question 16

What happens when you cook vegetables at high heat alone?

Answer 16

Pectin methyl esterase is not active, and the pectin network within the vegetables cells is more prone to breaking down.

Question 17

TEST KITCHEN: VEGETABLES COOKED ON HIGH HEAT, COVERED THEN UNCOVERED, COOKED IN A WATER BATH AT 150 DEGREES FOR 30 MINUTES AND ROASTED.

Answer 17

Roasted were wrinkled and lost 62% of their weight; covered then uncovered were less wrinkled and lost 60% of their weight; water bath and roasted weren’t wrinkled and lost 53% of their weight.

Question 18

What does covering a vegetable with aluminum foil in the oven do?

Answer 18

It steams them in the oven until it’s removed.

Question 19

Do the shiny and dull sides of aluminum foil work the same? Mashed potato test.

Answer 19

Yes, heating mashed potatoes with shiny side facing the food heated up a bit faster; difference was so slight they concluded no difference.

Question 20

How is aluminum foil made? Why does one side shine?

Answer 20

By passing two layers of foil through a rolling mill at the same time. The side in contact with the rolling mill comes out shiny, while the other side is dull.

Question 21

Describe the perfect roasted sweet potatoes.

Answer 21

Nicely caramelized exterior, a smooth, creamy interior and earthy sweetness.

Question 22

What does “cold start, finish sweet” mean when cooking mashed potatoes?

Answer 22

The less sweet potatoes browned, the sweeter they became.

Question 23

Why are sweet potatoes noticeably sweeter with lower oven temperatures?

Answer 23

The starch in sweet potatoes is converted to sugar between 135 and 170 degrees. Once the internal temperature exceeds 170, no further conversion takes place. Thus, the lower the temp, the longer they will stay within this range; this is called the “sweet zone.”

Question 24

What happens when you store sweet potatoes in the refrigerator?

Answer 24

It can cause them to develop a tough interior, even when cooked for long period of time.

Question 25

How should sweet potatoes be stored?

Answer 25

At room temperature, away from light.

Question 26

Why do sweet potatoes develop hard centers when refrigerated?

Answer 26

During chilling stage, sweet potatoes’ cell walls become more permeable, allowing the calcium ions located between cells to enter into the cell walls. Warming them to room temperature activates an enzyme called pectin methyl esterase. The enzyme alters pectin in a way that allows it to react with the calcium ions, strengthening the pectin molecules in the cells’ walls so they can’t be broken down.

Question 27

What draws out carrots natural sugars and intensifies their flavor?

Answer 27

Roasting

Question 28

Carrots contain more _____ than any other vegetable.

Answer 28

Pectin

Question 29

Do Brussels sprouts taste overly bitter and sulfuruous at times?

Answer 29

Yes

Question 30

Broccoli, radish, cabbage, Brussles sprout and mustard green are all part of what family?

Answer 30

Crucifer family

Question 31

Brussels sprout are rich in flavor precursors. What does this mean?

Answer 31

Flavor precursors react with the vegetable’s enzymes to produce pungent new compounds when cut, cooked, or even eaten.

Question 32

Handling Brussels sprouts just right helps them take os what flavor?

Answer 32

Nutty sweetness

Question 33

How should you arrange cut Brussels sprouts when cooking? Why?

Answer 33

Cut side down for optimal browning and extra flavor.

Question 34

Why do you sprinkle Brussels sprout with oil AND water before roasting?

Answer 34

Each piece hold on to a little water that acts like a steam chamber when covered with foil, helping the interior to cook through.

Question 35

As with oven-raosted vegetables, should you also precook before browning on a stove?

Answer 35

Yes

Question 36

Is the oven really your best choice for larger vegetables such as cauliflower and sweet potatoes?

Answer 36

Yes

Question 37

How do you steam smaller vegetables on the stove if they’re not cooked in water first?

Answer 37

Cover them with a lid before browning.

Question 38

Can pencil thin asparagus be covered and cooked?

Answer 38

Not really, it cannot withstand the heat and overcooks too easily.

Question 39

When sautéing, how does butter help cook asparagus?

Answer 39

The moisture inside helps steam the vegetable.

Question 40

Why is asparagus better when steaming before sautéing?

Answer 40

Raw asparagus is dry and waxy; the sugars necessary for browning are locked up inside the plants tough cell walls–cooking is required to release these sugars.

Question 41

What is a cooking medium?

Answer 41

Instrument by which something is accomplished.

Question 42

Does a crowded pan help increase the steam effect?

Answer 42

Yes

Question 43

When using a small sauté pan, what direction should asparagus spears be facing for maximum browning?

Answer 43

Half facing one way, half facing the other.

Question 44

Best way to store asparagus?

Answer 44

Trimmed, standing upright in a glass, with a bit of water (1 inch up the stalk) in the refrigerator.

Question 45

TEST KITCHEN: STORED ASPARAGUS IN PLASTIC BAG, PAPER BAD WITH WET TOWEL AND STANDING UPRIGHT IN WATER.

Answer 45

Plastic bag was slimy, paper bag had shriveled tips and limp stalks, standing in water were bright and fresh.