The general rule, is that only 50% of meals and entertainment are deductible.
This means if you are a sole-proprietorship you can only deduct 50% of this amount. The balance is treated as a draw for tax purposes.
But, the question you ask also addresses the point, what are qualified business expenses. Qualified business meals and entertainment expenses are explained in detail in IRS publication 463.
The IRS rules defines meals and entertainment and conditions for deductibility, as follows. The IRS verbage is as follows:
What are considered Business Meals?
" Business meals are classified as expenses for meals and meetings that occur during the course of business.
What kind of paper trail is required in order to gain deductibility?
A receipt and the specific business reason for holding the meeting, including the names of those attending must be submitted along with the request for reimbursement."