CONCEPT 26: POTATO STARCH CAN BE CONTROLLED Flashcards Preview

THE SCIENCE OF GOOD COOKING > CONCEPT 26: POTATO STARCH CAN BE CONTROLLED > Flashcards

Flashcards in CONCEPT 26: POTATO STARCH CAN BE CONTROLLED Deck (46):
1

Are there simple steps to remove or activate starch in potatoes?

Yes

2

Starch granules in a potato begin to absorb moisture at what temperature?

140 degrees Fahrenheit.

3

At what temperature to starch granules swell intensely?

160 degrees Fahrenheit.

4

What happens when starch granules get too hot and absorb too much water?

They can rupture, spilling out a sticky gel made of amylose.

5

What happens if potato cells holding these starch granules also explode?

The released amylose will create a gluey mess.

6

At what temperature does a "gluey mess" become a significant problem? What is happening?

At 180 degrees, pectin--which acts as a glue surrounding the cells and within the cell walls--begins to break down, becoming water-soluble, and dissolves, causing the cells to separate and cell walls to break open, releasing gel.

7

Is overcooking the only way to create gluey potatoes?

No, these starch granules can also explode if the potatoes are overworked after cooking.

8

To prevent a gluey dish, when can you rinse potatoes?

Before, during or after cooking.

9

What are two ways you can manipulate free starch when needed for a more sticky, tacky texture?

Stirring or a food processor.

10

Is the potato starch amylose held within starch granules before cooking?

Yes

11

When starch granules burst and release amylose, what does it form?

A gluey gel.

12

TEST KITCHEN: FOLDED MASHED POTATOES AGAINST FOOD PROCESSOR.

Folded were remarkably fluffy while food processor created a sticky, gummy substance; closer to glue than mashed potatoes.

13

How much water does a Russet potato contain?

About 79%

14

How much water root vegetables like carrots, parsnips, celery root and turnips contain?

Between 80 to 92%

15

How much starch do root vegetables like carrots, parsnips, celery root and turnips contain?

Between 0.2 and 6.2% wet weigh

16

Many root vegetables are noticeably ______ or slightly ______.

sweet, bitter

17

When mixing other root vegetables with potatoes, what is a good ratio? Why?

1:3 vegetables to potato is good for two reasons. One, root vegetable flavor can overwhelm the mild potato and, two, the root vegetables have far more moisture in them.

18

Do you wash away excess potato starch when boiling and braising? Explain.

When boiling peeled chunks of potato, you wash away excess starch as part of the cooking process. Braising, however, means the finished dish will contain all the starch.

19

What is potato Rösti (Roesti)?

A Swiss dish consisting mainly of potatoes. It was originally a common breakfast eaten by farmers in the canton of Bern, but today is eaten all over Switzerland and also in many restaurants in the western world. Many Swiss people consider rösti a national dish.

20

Is Roesti traditionally cooked in butter?

Yes

21

Best way to prepare Roesti?

Shred, rinse and squeeze

22

What will excess starch and moisture do to the center of a Roesti?

Cook up gummy in the middle; precooking potatoes helps control this problem.

23

When make Roesti, washing away too much starch will cause potatoes to do what? How is this fixed?

Lose their cohesiveness and fall apart when sliced. Adding cornstarch helps bind, crisp and brown the potato cake.

24

Lightly packing the shredded potatoes in Roesti does what?

Allows a place for steam to escape.

25

Name two dishes that would require extra free starches.

Cheesy mashed potatoes or roasted potato slices with a great exterior browning.

26

What is French aligot?

A dish traditionally made in L'Aubrac region in southern Massif Central of France made from melted cheese blended into mashed potatoes, often with some garlic.

27

Why would Yukon Gold potatoes be a good fit for alight? Explain.

Russets have an enjoyable, earthy flavor for mashed potatoes but, with all the stirring, they can become far too gluey; Yukon Gold has just enough starch.

28

Two things that causes potato starch granules to burst.

Rough handling and overcooking.

29

Why would you add butter to potatoes before milk and cheese?

Coating of butter makes starch molecules more compatible with cheeses so they are more able to combine with proteins. If milk is added first, the starch become so wet it resists interaction with fatty cheese.

30

Why add mozarella and Gruyère to alight?

Mozarella supplies stretch, Gruyère supplies nuttiness.

31

Is cheese the lone component that gives aligot its super stretch? Explain.

Unlike starch from other plants, the molecules in potato starch contain a small number of negative electrical charges. When combined with cheese proteins, parts of which contain positive electrical charges, an electrical bond between the two is created; when curly amylose molecules bond with cheese proteins, the combination becomes very springy and stretchy.

32

How long should you stir alight for the right consistency?

3 to 5 minutes.

33

What draws potato starch and sugar to the surface?

A quick simmer.

34

For browning, why are disks better than chunks?

Discs have more surface area to brown.

35

How do potatoes rely on moisture for browning?

Moisture must be present for starch granules to swell and release amylose. In turn, amylose will break down into glucose which darkens when exposed to high heat.

36

Is the oven alone effective enough to brown potatoes? Explain.

In the dry heat of an oven, caramelization is a lengthy process because starch granules swell slowly. Parboiled potatoes are swimming in the requisite moist heat, releasing a lot of amylose on the potatoes surface; transfer from one to the other, they'll brown immediately.

37

How do you rough up potatoes before roasting? Why does this work?

Vigorously tossing them in oil and salt will riddle potatoes with tiny dips and mounds. This creates a more exposed surface area and escape routes for moisture--browning is even faster.

38

Will preheating the baking sheet cook potatoes faster? Explain.

Yes, it allows a faster cooking time; greater moisture retention.

39

Crisping and browning begins after what evaporates?

Surface moisture

40

Does five square miles of Colorado's mountain region have more surface area than 5 square miles of the Kansas plains?

Yes, try walking them both.

41

Why are Yukon Golds best for roasting?

Enough moisture so the interior is cream, enough starch so the exterior is crispy.

42

When parboiling potatoes, what helps break down the exterior faster?

An alkaline environment with baking soda.

43

Ratio of baking soda to water for parboiled potatoes.

10 cups water to 1/2 teaspoon baking soda.

44

How does baking soda turn the outsides of potatoes to mush in 1 minute?

Alkaline baking soda triggers a chain reaction that literally unzips the backbone of pectin molecules, causing them to fall apart.

45

How much alkali do you need?

Only enough to raise the pH of the water high enough to start a reaction., after which it becomes self-sustaining; 8.1 was the books number.

46

How could you boil potatoes to keep their shape for a salad?

Add vinegar to drop the pH around 3.

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