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What Are the Causes of Spots on the Meat of Pears?

Often, farms and orchards where pear trees are grown and harvested take great pains to keep their fruit from blights such as worms, insects and other natural detractors. The pears that do not hold up to scrutiny during the harvesting process often find themselves discarded. As harvesting is a human endeavor, perfection in this process is not always attainable and mistakes are made. There are several causes for a post-harvest pear having blemishes on its surface and meat.

Rubbing, Scuffing and Bruising
- Abrasions happen in the packing process. Sometimes the fruit will rub other fruit, or the sides of boxes, or even hard surfaces. When this happens, bands of discoloration may occur on the surface and meat of the pear, or simply dark spots. This is called "friction bruising." If a bruise appears on the meat alone, and was not visible before peeling, it most likely occurred as a result of impact, thus giving it the name of "impact bruise." A flat place on a pear that turns discolored probably resulted from a "compression bruise."
Molds and Rots
- Many types of molds and fungi exist that target fruit trees, not just pears. One is the blue mold, which can create rotting in both apples and pears. Most cases of "rots" are also caused by some type of mold infecting the plant post-harvest and breaking down the outer and inner tissues. Examples include the grey mold, pink mold, bull's-eye rot, sooty blotch and powdery mildew to name a few.
Insects and Scalds
- Not every ugly spot on a pear happened post-harvest, but may have occurred beforehand and simply got overlooked. These can include various insects and scalds. Two forms of scald exist: the superficial scald and the senescent scald. In the first case, the discoloration only happens on the mature skin. In the second, it runs deeper and alters the meat, the taste and the smell of the mature fruit. Insects that can harm pears and cause blemishes include the codling moth, tarnished plant bug, thrips, plum curculio and pear scabs.
Chemical or Freezing Injuries
- Almost all commercially grown pears will encounter some form of chemical during their growth, usually to keep them healthy and insect-free. However, when growers misuse their chemicals, injuries will develop on their produce. Chemicals that can injure pears include ammonia, copper and sodium orthophenylphenate. Another form of injury occurs when pears are exposed to freezing temperatures for long periods of time, though this injury is no longer as prevalent as it once was thanks to modern refrigeration and handling techniques.

Nature