Here is an article we thought might be helpful on keeping your kitchen drain (and other drains) odor free.
By Tom Gillece
An odorous kitchen sink drain can be unpleasant and unhealthy. Remainders of food from 
dishes rinsed in the sink or from food that is put into the garbage disposal can become entrapped in the drain or disposal, causing mold and bacteria to grow and odors to form over time.
There are several ways to refresh a kitchen sink drain and garbage disposal to eliminate odor as well as mold and bacteria, using items that may already be in the kitchen. Hot water, baking soda, vinegar, fruit, and ice are some of the substances that can be used to refresh a drain through cleaning and deodorizing.
Hot water, at boiling point, run from the kitchen sink faucet into the kitchen sink drain, can work to kill bacteria and mold. After running the water for roughly 15 seconds, a teaspoon of baking soda can also be added, followed by an additional 15 seconds of hot running water. Baking soda works to kill odors, just as it does when kept in the refrigerator.
If baking soda is added following hot water, vinegar may be added into the mix, creating a reaction that loosens any particles within the drain. This mixture should sit for approximately 10 minutes. Then, boiling hot water may be run down the drain to rinse away any food particles that have been loosened.
Another odor eliminator that can be found in the kitchen is fruit, such as lemon or lime halves and other citrus peels, which can freshen any unpleasant scent coming from the kitchen sink. They can be run as normal in the garbage disposal to produce a clean, fresh scent. Adding fruit peels in with ice is also recommended. Ice can potentially clean and sharpen garbage disposal blades as it is ground up by the disposal, removing any food that is stuck there.
Bleach is another option for killing bacteria and getting rid of foul odors coming from the kitchen sink, but it can harden grease residue that may be left in the drain. Other chemicals can possibly damage a garbage disposal or drainpipes and should not be poured into the kitchen sink. To eliminate grease residue, use grease-fighting detergent or dish soap and try not to pour grease down the sink, if possible.
Methods for refreshing a kitchen sink may be repeated anywhere from one to three times a week, depending on how often the sink is used and how thoroughly it is cleaned on a daily basis. It is also important to remember that water should be run while the garbage disposal is working to dispose of food. It can take up to a gallon of water to rinse the disposal once food has been removed. If the kitchen sink does not have a garbage disposal, make sure to dispose of any leftover food in a garbage can instead of down the drain.
One other drain-clearing method helps to clear out not only the kitchen sink, but all drains in the home. All sinks and tubs should first be filled with water. Then, each drain plug should be pulled simultaneously, while also flushing each toilet in the home. The sudden rush of water created by releasing the drains and flushing the toilets at the same time helps to clear out drains throughout the home. This can be done about four times a year to keep drains working smoothly.
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