How to Clean a Coffee Thermos – Comprehensive Guide

It’s only better to take your morning coffee with you when you can take it in the car. Use of your favorite travel mug every day, however, can lead to coffee stains and grime. Therefore, all coffee drinkers need to learn how to clean a coffee thermos.

Thermoses are a bit more difficult to wash than coffee mugs. There are some items where running them through the dishwasher won’t do, and you’ll need to get creative. This list is for you if you find that regular cleaning and scrubbing with soapy water still leaves crud on the bottom of your coffee thermos.

The following article will provide you with some tips and recipes for removing stains and coffee residue from your favorite thermoses. You probably already have some of the ingredients in your kitchen or bathroom for each of these cleaning solutions.

Cleaning a Coffee Thermos

You probably have stains on your thermos if you drink a lot of coffee. You don’t need to buy a new travel mug every couple of months; you just need to know how to clean and care for your thermos.

Thermoses can be cleaned with the same ingredients that you use to clean out a coffee maker. A few basic supplies and a few minutes are all you need.

How to Clean a Coffee Thermos

Understanding how to wash your coffee thermos is the key to having a stain-free one. You shouldn’t put a vacuum flask in the dishwasher. Fill it with warm water and dish soap instead. Allow it to soak for about five minutes without submerging it in water.

Use a sponge or bottle brush to scrub it thoroughly after soaking. Rinse it with hot water, dry it thoroughly with a dishcloth, and let it drain with the lid off. Give your thermos a quick rinse with warm water before each use to keep it fresh.

If you don’t have a vacuum flask, you can use a homemade dishwasher detergent recipe or your regular commercial detergent. The thermos should be placed on the top shelf.

Cleaning a Coffee Thermos with Baking Soda and Vinegar

You need to add more ingredients if you haven’t cleaned your coffee thermos for a while and a simple wash with dish detergent and water doesn’t work. White vinegar and baking soda should remove any stains on your thermos. This recipe can also be used to clean a coffee maker with bake soda and vinegar.

Vinegar and Baking Soda Cleaner

• ½ cup of distilled white vinegar
• 1 or 2 tablespoons of baking soda
• Hot water

Add one or two tablespoons of baking soda to your thermos, depending on how many cups it holds. Swish the baking soda and vinegar cleaner inside the thermos, holding it over the sink in case the solution foams. The cap should not be placed on the spout.

Pour hot water into the flask once the foam from the mixture settles down. Let the cleaning solution sit for approximately ten minutes. Scrub the inside of the thermos with a bottle brush that is designed to reach those hard-to-reach areas so you get every stain.

Rinse the mixture with hot water several times, until it no longer smells of vinegar. Let the thermos air dry the rest of the way. Not only is this the best way to clean a coffee thermos, but it can also be used to clean your coffee maker or favorite water bottle.

You can easily remove coffee pot stains with vinegar and baking soda. This powerful combination makes a great descaler for getting rid of mineral buildup and debris that often accumulate inside coffee pots. There are a number of cleaning tasks around the house that vinegar and baking soda are perfect for.

Lemon Juice to Descale a Thermos 

A thermos descaling solution is also a great way to clean your flask. Thermostats or appliances you use every day can accumulate buildup and stains very quickly. To wash away this dirt, you can use a natural descaling solution like lemon juice.

Fill your thermos with equal parts lemon juice and water. Scrub it with a bottle brush or sponge after letting it sit for about five minutes. Rinse the mixture several times to remove the lemon scent. Your coffee pot will also benefit from this cleaning solution.

Remove Coffee Stains from Stainless Steel Thermos with Ice and Salt

You might not have heard of this cleaner before, but it works! Once your thermos is empty, fill it a quarter of the way with crushed ice cubes. Salt the mixture with two to three large spoonfuls. Salt with larger grains, such as sea salt or coarse-ground salt, works best.

Shake your thermos well after you have closed the lid. Salt and shards of ice will scrape away stains and buildup on metal. Shake it until the ice and salt are dissolved.

Fill the flask with warm water after removing the mixture. Pour out any leftover debris after swirling it around. Rinse the bottle several times to remove all traces of salt, and then leave it to dry.

Remove Coffee Thermos Stains with Denture Tablets 

It might sound surprising, but here is another cleaning tip. Sodium bicarbonate, otherwise known as baking soda, is one of the main ingredients in denture cleaner tablets. As denture cleaning tablets are designed to clean objects that go in the mouth, they are also perfectly safe to use on your flask.

Fill your thermos halfway with boiling water. Allow it to sit for a few minutes to loosen the stains and other residue. Get every part of the interior wet by swirling the water around. Add one or two denture cleaner tablets.

As the water starts to bubble and foam, hold your thermos over the sink. Remove the cap. After about half an hour, pour out the mixture from the flask. Rinse the container with fresh water a few times and then allow it to dry.

Clean Thermos Flask with Hydrogen Peroxide

A stronger cleaning agent might be necessary if you try one of the other cleaning tips but find that your stain is too tough. In the baking soda and vinegar cleaning solution, hydrogen peroxide can be used instead of vinegar.

Additionally, hydrogen peroxide is the primary ingredient in homemade antibacterial sprays, so you can be sure your flask will be sanitized at the same time as it is cleaned. Hydrogen peroxide is certainly effective for coffee stains, but it is especially useful for food thermoses.

You should, however, rinse your flask thoroughly after cleaning it with hydrogen peroxide. Before using it, you may want to give it a quick clean with water and dishwashing liquid.

This solution can also be used to remove stains from coffee cups. It’s an ideal cleaner and sanitizer for all kinds of items in the kitchen and bathroom.

Remove Coffee Stains with Dishwasher Powder

Coffee stains and a variety of other stains can be removed with dishwasher powder. Powder is more effective than liquid because it is abrasive and can scrape stains off. To clean your thermos with this method, you’ll need one tablespoon of powder per quart.

Fill your thermos half full with dishwasher powder and hot water, but not to the brim. Shake the thermos for a few seconds after placing the lid on it. Remove the lid and fill it with water to the brim.

Leave the lid off overnight. Pour about half of the solution out the next day and scrub the inside of the bottle with a bottle brush. Let it air dry after emptying and rinsing a few times. Rinse your thermos as soon as possible after using it to prevent coffee stains. Stains form when the dregs of your coffee sit in it for a while.

Your thermoses, coffee cups, and flasks can quickly get soiled, especially if you use them every day. Rather than throwing out your favorite items, you can remove coffee stains from stainless steel thermoses, remove hard water stains from stainless steel, and clean other items using cheap, accessible, and safe solutions. Our tips are all fast-acting and easy to follow.  We also have compiled a guide that will help you choose coffee thermos for work, if your are looking for the best one.