Why You Shouldn't Throw Potato Peels Down the Garbage Disposal

If you're wondering whether potato peels can really cause damage to your garbage disposal or plumbing system, the answer is yes—there's actual science behind why they should be avoided. Wet potato peels, when put through your disposal, create a perfect storm for clogs and mechanical damage. Understanding how potato peels interact with your plumbing can save you both time and money in the long run. Here's a breakdown of why these peels can spell trouble for your system.

Introduction

Potato peels may seem harmless enough, but when they’re wet and make their way into your garbage disposal, they can create more problems than you might expect. Not only do these peels contain large amounts of starch, but they also possess fibrous properties that, when combined with water, lead to a variety of issues that can compromise your plumbing. In this post, we’ll break down the science behind why wet potato peels can cause plumbing issues, and why it’s a good idea to avoid putting them in your disposal altogether.

Yes, there is actual science behind why potato peels, specifically when wet, are the most harmful to your disposal and plumbing system. Here's the breakdown from the science point of view:

Starch Absorption and Paste Formation:

The peel of potatoes contains a lot of starch. The starch dissolves when the peels get wet, turning into a thick, gooey liquid. This starch has a tendency to gel, which forms a real sticky paste. Once this gel enters the disposal, over time it can easily clog the blades and the internal workings of the disposal. This paste can stick to the sides of the pipes, producing sluggish drainage with time.

Water Retention in Fibers:

The peels of the potatoes themselves are fibrous in nature, which then absorb water when wet and swell up. Such swelling increases the chances of clogging, since they may expand and jam the disposal unit or get tangled within the grinding mechanism.

Increased friction and wear of blades:

As the wet potato peels are processed, their fibrous texture can create significant friction against the disposal blades. Over time, this will dull the blades, reducing the efficiency of the disposal. The mechanical stress further increases the likelihood of overheating of the disposal motor, which can lead to premature wear and even failure.

The "Cementing" Effect:

Starch from potato peels, combined with other organic material in the disposal, forms a "cement-like" slurry. Once hardened, this is quite difficult to break down and can block the disposal or plumbing, restricting the flow of water.

Hydration of Organic Material:

The high moisture content of potato peels can also increase organic waste, which might stick together more easily in the pipes. With time, it can build up as a thick layer that is very difficult to clean, and you will probably need the services of a professional plumber. 

From a plumbing science aspect, the mixture of fibrous and starchy matter with water encourages the potential for blockage and abrasion on mechanical parts, along with the building-up effects that impede the smooth passage of water. It's a good practice to avoid putting potato peels in the garbage disposal and instead dispose of them through composting (fertilize some flowers or tasty vegetables) or in the trash.

FAQs:

1. Why do wet potato peels cause clogs in garbage disposals?
   Wet potato peels contain starch that dissolves in water, turning into a sticky paste. This paste can clog your disposal’s blades and internal components, leading to sluggish drainage and potential blockages.

2. What happens to the potato peels after they go down the disposal?
   As potato peels are processed, their fibrous nature absorbs water and swells up, which can lead to them getting stuck in the grinding mechanism or jamming the disposal altogether. This can cause the motor to overheat and wear out faster.

3. What’s the best way to dispose of potato peels?
   Instead of throwing them in the garbage disposal, composting potato peels is an eco-friendly option. If composting isn’t viable, simply throw them away in the trash to prevent potential damage to your plumbing.

Credits

This article was inspired by questions from Rachael O'Connor at Newsweek .

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