By default, the Storefront will append the product name to your page title (e.g. "MySite > Product"). To change the page title format, you can change adjust the static localization from the persona bar Settings > Site Settings and edit the static localization for your language. Then drill down to the node and look for the Format.PageTitle.Text values.
Local Resources
DesktopModules
Revindex.Dnn.RevindexStorefront
App_LocalResources
SharedResources
The {0} token is replaced with the Web site name as defined in your DNN settings, the {1} token is replaced with the product name.