Everyone has a favorite apple variety but what makes it so? How do Washington State University’s new apple varieties WA 2 and WA 38 compare with each other, and with existing commercial varieties?
Consumers and producers may not always agree when asked what characteristics they desire in a new variety. Here, we will focus on eating quality preferences of consumers rather than typical grower interests of return on investment influenced by yield, packout, market demand, and price. Growers also realize that each of these factors is influenced either directly or indirectly by fruit quality.
To please consumers, new varieties must meet high standards for both texture and flavor. Texture includes firmness, crispness, and juiciness (negatives being soft, chewy, dry, and mealy). Flavor includes sweetness, tartness, aroma, and other unique tastes (negatives being flavorless, not sweet enough, too sour, and bland).
Fruit texture typically trumps flavor. When a person takes the first bite from an apple, they perceive the firmness first with the force of teeth sinking into the apple.
As the bite continues, the flesh of the apple is fractured with an accompanying sharp cracking sound, which is a measure of crispness. As the person chews the apple, the cells rupture and the juiciness becomes apparent. If this first impression from biting and chewing is soft, chewy, tough, dry, or mealy, the consumer is discouraged from moving onto the delights of flavor. The biggest complaint from consumers is that apples generally are soft. It is essential that new varieties, when removed from medium and long-term storage, are firm, crisp, and juicy.
Once juice is released, taste sensors measure the dominant flavor traits of sweetness (sugars) and tartness (malic acids), and apple aroma is revealed. A dozen or more aromatic flavor compounds create the apple flavor. Some varieties have secondary nonapple fruit flavors, including pineapple, peach, pear, citrus, and banana, or even nonfruit flavors, such as cinnamon, honey, vanilla, and licorice, which can contribute positively to the eating experience. Unlike wine flavors with fashionable descriptors (notes of berry, citrus, licorice, and spice; floral tones; lively acidity), there is little sophistication in describing or appreciating apple flavors and textures. This could and should change with some savvy marketing and new varieties.
Many consumers and some marketers believe that sweetness and tartness represent opposite ends of a single scale. This is a misconception. Sweetness and tartness are separate traits and are controlled independently by separate genes. Any sweet/tart combination is possible. For example, Cripps Pink has high sweetness and high tartness, Fuji has high sweetness and low tartness, and Delicious has low sweetness and low tartness.
Consumers generally prefer sweet apples. However, tartness (if not extreme) gives fruit much of its character and can make it tasty and flavorful. For some consumers, the high acidity of Granny Smith and even of Braeburn is a negative, perhaps because those varieties lack sufficient sugars to mask the high acidity. The blandness of low acidity is a turnoff for many consumers, but not all.
WA 2 and WA 38
To illustrate the eating quality of WA 2 and WA 38, we have compared them with nine commercial cultivars (Figure 1). These three distribution diagrams show the values for six fruit quality traits: firmness, crispness, acidity, soluble solids, fruit weight, and juiciness. The objective is to show the relative differences between varieties. For example, we know that Granny Smith and Fuji are opposites in terms of flavor: Granny Smith is highly acid and not very sweet while Fuji is sweet with little acidity. The acidity/soluble solids diagram clearly shows these differences.
Fruit-quality values are influenced by three important factors: fruit maturity at harvest; crop load; and type and length of cold storage. Overmature fruit is sweeter and softer than less mature fruit; fruit from trees with a heavy crop load is less sweet and smaller than fruit from trees with a light crop load; and, with an increasing length of storage period, acidity declines and fruit softens.
The relative distribution of varieties in our diagrams would be the same no matter where the fruit is grown and is primarily the consequence of their genetic makeup. The genetics of fruit quality generally overrule cultural or environmental factors.
Figure 1 shows that fruit of these new varieties, whether fresh or from regular or long-term controlled-atmosphere (CA) storage, is impressive in texture (high crispness and firmness) and flavor (balanced sweetness and acidity). Fruit of WA 2 is firm, and WA 38 is almost as firm. Both are firmer than Gala and Fuji, and retain their firmness in long-term storage. Fruit of WA 2 and WA 38 is very crisp and has greater crispness than Gala, Fuji, or Cripps Pink. Their crispness compares favorably with Honeycrisp, the consumer standard for crispness.
It is this rare quality of being both crisp and firm out of medium and long-term storage that separates WA 2, WA 38, and Jazz from other cultivars. WA 2 is intermediate in juiciness. WA 38 is very juicy, more so than WA 2 and almost all long-storing commercial cultivars. WA 38 achieves the trifecta, the combination of firm, crisp, and juicy.
Eating quality may be optimal directly off the tree or after several months of storage. Selecting the right market window is critical to assure high quality. WA 38 is outstanding at harvest and also following many months of cold storage. WA 2, on the other hand, can be starchy and less flavorful at harvest but mellows and achieves very high eating quality after two or three months of storage and is at its best from late January onward.
Distinct from eating quality, but also important to consumers, are the appearance traits of fruit size, skin color, nonbrowning flesh, uniformity, finish, and defects. Some consumers buy with their eyes. WA 2 and WA 38 are both attractive. The skin of WA 2 is more than 70 percent crimson red with yellow background and conspicuous lenticels. The skin of WA 38 is more than 80 percent dark burgundy red. WA 2 fruit is medium in size and larger than Gala. WA 38 fruit is large and equal to or larger than Fuji (Figure 1).
Both new cultivars have uniform fruit with a clean skin and minimal russet, sunburn, or bitter pit. These features contribute to high packout for WA 2 and WA 38. WA 38 has nonbrowning flesh, a feature not found in other commercial varieties discussed here.
Consumers may try new varieties based on appearance, but for repeat purchase, the eating quality traits of texture and flavor are paramount. Individual labeling of apples offers a perfect marketing opportunity to link variety name with a message to the consumer emphasizing the high-quality attributes of these new varieties. The combination of exceptional eating quality based on pleasing texture and flavor and an attractive appearance suggest that WA 2 and WA 38 have significant commercial potential.