The people at Arm and Hammer TM urge the use of their baking soda to deodorize your refrigerator and freezer.1 Use of it is said to prevent “funky” tasting food. Is it really true? Baking soda – sodium carbonate – has been praised for its many uses in cooking and in cleaning, but does baking soda really deodorize your refrigerator, or is it merely sales hype?
A Brief Bit of Chemistry
Before answering that question outright, let’s consider the chemistry of baking soda, just a bit.
Baking soda possesses the chemical formula, NaHCO3. This structure is a very interesting one! Sodium bicarbonate is the more technical name of baking soda. It can be made by reacting lye (sodium hydroxide or NaOH)2 with carbonic acid (or H2CO3 found in soda water). Thus,
NaOH + H2CO3 -> NaHCO3 + H2O
Baking soda is slightly alkaline, but thanks to the remaining hydrogen (an acidic hydrogen) in the molecule, it can react with substances more alkaline than itself.
This makes it possible for baking soda to react with all acids, and many bases, too.
Chemistry aside, we come back to the question: Does baking soda really deodorize your refrigerator? There is some concession that it can do a tiny bit of that – toward acidic materials, such as sour milk, onions, etc. Others feel that because it can react with fairly strong bases, it does more than many people realize. Fish odors – chemically amine related – that are known bases may be removed by baking soda.3
Some feel strongly that baking soda does very little to remove odors – that something such as charcoal, a substance known to remove odors, would be more advisable.4 There are claims that a box of baking soda in the refrigerator is like a placebo to a patient – it may provide some benefit, but only psychologically. Others – maybe the majority of persons – whether rightly so or not, feel that baking soda does help reduce the presence of undesirable odors.
The jury is still out
One thing is certain. At such a low cost, it can’t really hurt to open a box of baking soda and put it in a convenient place in the refrigerator. After time has passed and you wish to replace that box, its contents still be used for cleaning general surfaces.
Any questions for the Kitchen Chemist? Please feel free to make comments in the section provided below this article.
2 Lye is a very strong caustic substance that needs very careful handling, according to instructions found on its container. There is no need to obtain any to benefit from this article.
3 Indiana University, A Moment of Science (AMOS).
4 Newton BBS, Argonne National Laboratory, Ask a Scientist, Baking Soda and Odors.