Fruit flies can be a problem year round, but as the weather warms up; temperatures in the kitchen heat up and windows and doors are opened, so you typically start seeing them in spring.
We’ve created this fact sheet for you to explain how infestations originate and how you can prevent them in your correctional kitchen this year:
Biology and Behavior
Fruit flies are common in all types of kitchens; correctional operations, restaurants, school cafeterias and even homes. Anywhere with unrefrigerated produce will attract fruit flies.
- The adults are about 1/8th inch long and usually have red eyes. The front portion of the body is tan and the rear portion is black.
- Fruit flies lay their eggs near the surface of fermenting foods or other moist, organic materials.
- Upon emerging, the tiny larvae will feed near the surface of the fermenting mass. Because the larvae feed only on the surface on the over-ripened fruits and vegetables, the damaged area can be cut away without having to discard the remainder for fear of retaining any developing larvae.
- The reproductive potential of fruit flies is enormous, laying anywhere from 400 to 500 eggs. The entire lifecycle from egg to adult takes about one week.
- Fruit flies are especially attracted to ripened fruits and vegetable, but they also breed in drains, garbage disposals, empty bottles and cans, trash containers, mops and cleaning rags. Any area that has developed a moist film of fermenting material.
- Infestations can originate from over-ripened fruits or vegetables that were previously infested and brought into the home. Also, the adults can also fly in from outside through inadequately screened windows and doors.
- Fruit flies are primarily nuisance pests. However, they also have the potential to contaminate food with bacteria and other disease-producing organisms.
The best way to avoid problems with fruit flies is to eliminate sources of attraction:
- Produce which has ripened should be eaten, discarded or refrigerated.
- Bruised or cracked portions of fruits and vegetables should be cut away and discarded because eggs or larvae may already be in the damaged area.
- All areas where food is stored should be cleaned out. A single rotting onion remaining at the bottom of the bin, or fruit juice spillage under a refrigerator can breed thousands of fruit flies. So can a recycling bin with soda cans that aren’t rinsed which is not emptied or cleaned.
- Windows and doors should be tightly fitted with 16 mesh screens to help prevent adult fruit flies from entering from outdoors.
Once your operation is infested with fruit flies, every area that is a potential location for breeding must be located and eliminated. Until all breeding sites are removed or cleaned, the problem will continue no matter how often insecticides are applied to control the adults:
- Locating the actual source of attraction and breeding can be challenging and can require thoroughness, diligence and persistence. Potential breeding sites like garbage disposals and drains can be inspected by taping a clear plastic food storage bag over the opening overnight. If flies are breeding in these areas, the adults will emerge and be caught in the bag.
- After the source of attraction and breeding is eliminated, a pyrethrum-based, aerosol insecticide made for janitorial supplies for foodservice may be used to kill any remaining adult flies in the area.
- Alternatively, you can construct a trap by placing a paper funnel (rolled from a sheet of notebook or butcher paper) into a jar which is then baited with a few ounces of cider vinegar or a slice of banana. Place the jar trap(s) wherever fruit flies are seen. This simple trap will soon catch any remaining
adult flies for removal from your kitchen.
The busy correctional kitchen is a great location for the fruit fly to set up house! Working with facilities across the US, we’ve had plenty of customers come to us with this problem – and Cook’s Correctional has been able to help them with easy-to-implement, cost effective solutions. If you are concerned about a potential fruit fly invasion, give us a call and let us get you set up to stop them before they start this year.
Information courtesy of the University of Kentucky College of Agriculture, Food and Environment / UK Entemology webpage on Fruit Flies.