How to get Garlic & other strong Spices' smell out of my Zojirushi Flask/ Thermos acquired via a herbal Immunity decoction? How to get Garlic &amp; other strong Spices' smell out of my Zojirushi Flask/ Thermos acquired via a herbal Immunity decoction? 

Major components of this decoction were: 


Garlic cloves 
Black Pepper seeds 
Cinnamon 
Bay Leaf 
Ginger 
Cumin seeds
Turmeric powder
Coriander powder 
Fennel seeds 


Flask Product &amp; Materials info: 

https://www.zojirushi.com/app/product/smkhe 


Its SlickSteel® finish interior is corrosion resistant and repels stains.
Durable and sanitary 18/8 stainless steel interior with SlickSteel® finish 
Made of BPA-free plastic and stainless steel
Structure, design &amp; details as pulled from product website 






Mine is the Stainless Steel colored 16 oz one:  



More data from Manufacturer's website FAQ and Manuals: 

[QUOTE]
Q3: How can I clean my vacuum bottle?
A: Always rinse out your vacuum bottle after each use and rinse the stopper under running water. Do not soak the vacuum bottle in water or place in a dishwasher to clean. 

The exterior, stopper and cup(s) can be cleaned using a moist sponge or soft cloth and mild dishwashing liquid. 

The interior can be cleaned using a mild dishwashing liquid and then rinsed thoroughly. 

Please refer to your instruction manual for more.
[/QUOTE]

Manual: https://www.zojirushi.com/servicesupport/manuals/manual_pdf/smkhe.pdf
Wash out with warm soapy water. A toothbrush could help in the scrubbing. While still wet, add baking soda into the flask and scrub. 
Pour an inch or two of white vinegar into a clean carafe, then fill most of the way with hot tap water.
Not tried this one, but seems a few people have had good results. 4 Alka-Seltzer tablets with water. 
Adding freshly ground coffee, which will help to mask the smell if it is still there. 


Edit: 
Just read through the manufacturer's instructions, and have updated my advice as a result.