2.6 Varietal Differences


  • To determine the varieties of fruits and vegetables suited to specific uses.
  • To identify the characteristic differences in several varieties of fresh potatoes, apples, and oranges.
  • To prepare some varieties of potatoes and apples by different methods to illustrate uses for which each variety is best suited.

Laboratory Problems

  • Determine differences in texture and flavor of potato products due to varietal differences.
  • Determine differences in appearance, texture, and flavor of apple products due to varietal differences.
  • Determine varietal differences in oranges.


  • Potato Cultivars:
    • Waxy-type: Red Pontiac
    • All-Purpose-type Potato: White Chippewa, Yukon Gold, Klondike Gold
    • Mealy-type: Russet Burbank
  • Apple Cultivars:
    • Red Delicious, Golden Delicious, Jonathan, Gala, Braeburn, Pink Lady, Envy, Cosmic Crisp, Honey Crisp, Granny Smith, Fuji

Characteristics of potato varieties:

Type Variety Characteristics
White potatoes Waxy
Sweet Potatoes Dry-meated


Prepare assigned variety of potato according to the following directions.

Boiled Potatoes

Wash, peel, and quarter 2-3 medium potatoes. In medium saucepan, gently boil with ½ tsp. salt in enough water to cover until tender, 20-25 minutes; drain.


Mashed Potatoes

2 medium potatoes 1 tbsp butter
3-4 tbsp hot milk* dash salt
*Or 3-4 tbsp reserved cooked liquid and 1 tbsp nonfat dry milk

Wash, peel, and quarter potatoes. Boil with ½ tsp. salt until tender. Drain and mash until smooth. Add butter, and salt to taste. Gradually beat in milk with a potato masher until light and fluffy.


Instant Mashed Potatoes

Prepare two servings of potatoes according to package directions for stovetop.

Baked Potato

Heat oven to 425°F. Scrub potato. Bake on oven rack. After 20 minutes of baking, pierce each potato with a fork. Bake until potatoes feel soft when pressed with fingers, approximately 45 minutes total. Roll potato gently with hands; then cut cross in top with a knife and push in ends and sides of potato to fluff before serving.


Microwave Baked Potato

Scrub medium-sized potato and dry; pierce with fork in several places. Microwave-bake 3 to 5 minutes until potato feels soft when pressed with fingers, following specific microwave oven directions for power and time. Let potato stand for 5 minutes, then cut cross in top with a knife and push in ends and sides of potato to fluff before serving.



(Three general categories)

  • Mealy – glistening appearance; granular dry feeling on tongue; best choice for baked, mashed or French fries. (Russet Burbank)
  • All Purpose – intermediate between waxy and mealy. (White Chippewa, Yukon Gold)
  • Waxy – translucent appearance; feels pasty and wet on tongue; best choice for boiled potatoes and potato salad. (Red Pontiac)

Mealiness of potatoes is dependent on:

  • Variety (Russet varieties are mealy; red-skinned varieties are waxy)
  • Growing conditions (soil, climate, fertilizer)
  • Storage time (new potatoes tend to be waxy)
  • Storage temperature (above 50°F, sugar → starch; below 50°F, starch → sugar)

Sweet Potatoes

  • Dry-meated – mealy, yellow-to-tan flesh.
  • Moist-meated – soft, tan-to-brownish red flesh. (Often called yams; however the true yams are of a different genus.)

Characteristics of standard products and best uses for potatoes:

Boiled Potatoes

Variety: Red Pontiac—waxy.

Appearance Texture Flavor
  • White; slightly translucent
  • Firm, holds shape well
  • Little or no evidence of sloughing (peeling off in layers)
  • Mild; slightly sweet

Mashed Potatoes

Variety: Russet Burbank—mealy.

Appearance Texture Flavor
  • White
  • Glistening
  • Light, fluffy, and mealy
  • Neither pasty nor lumpy
  • Mild
  • Properly seasoned

Baked Potatoes

Variety: Russet Burbanks—mealy.

Appearance Texture Flavor
  • White
  • Separate, glistening particles
  • Mealy
  • Dry feel on the tongue
  • Mild



Variety of White Potato

Method Waxy All-Purpose Mealy Instant
Microwave Baked .                                     

Variety of Sweet Potato

Method Dry-meated Moist-meated


Characteristics of apple varieties:

Raw apple characteristics. Wash, slice and core samples of raw apple. Record observations.

Variety Flavor Texture Uses
Red Delicious
Golden Delicious
Granny Smith

Prepare assigned variety of apple according to the following directions.

Baked Apple

1 medium apple 1 tsp butter
1 tbsp sugar 2 tbsp water

Wash and core apple. Slit the skin around the center of apple. Place in a 1-pint glass baking dish and fill center of the apple with mixture of sugar and butter. Add water, cover with foil and bake covered at 350°F until tender, approximately 45 minutes. Add more water if necessary. Baste (pour accumulated juices over the apple) approximately every 8-10 minutes.

Boiled Apple Slices

2 medium apples 2 tbsp sugar
2 cups water

Wash, peel, quarter, and core apple. Slice into ¼-inch slices. Boil gently in water in covered saucepan until tender, approximately 8 minutes. Add sugar and continue to cook until apple slices are translucent, approximately 4 minutes more. Add more water if necessary.


Characteristics of standard products:

Baked Apples

Varieties: Golden Delicious or Gala

Appearance Texture Flavor
  • Apple intact
  • Skin color appropriate to apple variety
  • Tender, but not mushy
  • Distinct apple flavor

Boiled Apple Slices

Varieties: Golden Delicious or Granny Green Smith

Appearance Texture Flavor
  • Slices intact, plump (not shriveled), translucent
  • Yellow color, shade of yellow dependent upon variety of apple used
  • Tender, but not mushy
  • Distinct apple flavor

Evaluation of Cooked Apple:

Method Variety Appearance Texture Flavor
Baked Apple Red Delicious
Golden Delicious
Granny Smith
Boiled Apple Slices Red Delicious
Golden Delicious
Granny Smith


(Varieties selected for laboratory)

Red Delicious best eaten raw; loses mild delicate flavor and remains firm when cooked.

Uses: Fruit baskets

Jonathan all-purpose apple; has distinct flavor when eaten raw; retains tart flavor when cooked; has tendency to mush, making it excellent for sauce.

Uses: Applesauce

Golden Delicious all-purpose apple; has distinct fresh flavor; retains flavor and shape when cooked.

Uses: Pie, baked, escalloped apples

Granny Smith tart, crisp all purpose apple.

Uses: Baked, pie, escalloped apples

Fuji – sweet and refreshing; holds shape when cooked

Uses: eating raw

Braeburn complex, sweet and tart flavor; crisp and juicy; keeps well; retains sweetness when cooked; all purpose apple.

Uses: Applesauce

Gala crisp, very sweet, juicy; best fresh, loses flavor when cooked.

Uses: Fruit salads, raw

Honey Crisp – crispy, juicer than most, honey-sweet, pear flavor

Uses: baked

Pink Lady – crisp, balance of sweet and tart

Uses: raw, baked

Characteristics of Fruit Varieties:

Variety Characteristics Uses
Oranges – Navel
Oranges – Valencia


Varietal Differences in Selected Fruits and Vegetables


(Two principal market varieties)

Navel – marketed November to late May; no seeds; less juice than Valencias have; pebbled skin; separates into sections easily.

Valencia – marketed late March to early October; has seeds; more juice than navels have; skin may have greenish tinge.


Summer – soft rind; short storage life; high water content and low starch content.

Varieties: Zucchini, yellow squash.

Winter – hard shell; longer storage life; lower water, and higher starch content than summer squash have; yellow or orange flesh.

Varieties: spaghetti squash, acorn squash.


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