A SharePoint Publishing site can also be configured to make use of the ASP.NET output cache to store rendered ASPX pages in memory. You can only make use of this cache when the P**ublishing features are activated on your site collection. This means that only publishing pages can be cached.
User must be a site collection administrator or have full control within web application policy to modify this settings.
Here is code to disable it:
$cacheSettings = new-object Microsoft.SharePoint.Publishing.SiteCacheSettingsWriter($Url);
$cacheSettings.EnableCache = $true;
Save the file as DisableOutputCache.ps1 and run like this
powershell "& ./DisableOutputCache.ps1 -Url http://dev-moss.com"