All products expire from your Merchant Center account 30 days after the last refresh. Products can be refreshed by re-submitting your product data source or scheduling regular data source uploads. Google will also regularly check your website and refresh your products automatically if the product data can be validated, for example, by the crawling of schema.org structured data on your product landing pages.
You can remove product data or specific products at anytime.
Remove the item from your product data source: If you're updating your products using a data source, delete the products from your data source file and submit the product data source again.
In your Merchant Center account, click on the Settings & tools icon
.
Select Data sources.
Under the “Product sources” tab, select a product source you want to remove.
On the 3 dot menu icon
Click Remove.
(Optional) If you want to permanently remove the products, delete the products from your product data source before the next upload. If the products aren't removed from your data source, they'll be added to Merchant Center again on the next upload.
Use the expiration date [expiration_date] attribute: Add the expiration date to any item that you would like to remove on a specific date. Learn more about the expiration date [expiration_date] attribute.