There are two main things to consider when looking at the currency of something: finding a date and examining it in context.
Dates are easy to identify in library databases but less so in resources on the web. If you can not find the date easily, look around for a "page updated" line or a copyright date. Copyright dates are not a guarantee that the information was updated or reviewed as recently as that time. If you can't find a date
Currency can be relative. If you are looking for information about a disaster that happened a long time ago, information from that time can be extremely helpful. However, if you are researching a recent or current issue information that is dated can be outdated and irrelevant. It's important to identify a date and make decisions about the context of the information in time.
This is a pamphlet from 1861. This information is useful in that it gives you an idea of what people were discussing at the time about food rations among the enslaved.
This book is less than 10 years old but provides information about some of the historic and systemic discrimination that continues to impact food access. These types of resources can be especially helpful since the researchers have had time to evaluate the impacts of something.
Even though the blog post from the USDA in April 2021 refers to the 'food desert', they have been referring to this concept as low-income low-access for a while.
