Can I claim groceries as a business expense if I have a YouTube channel business where I cook and share recipes?

Sounds legit... https://www.irs.gov/businesses/small-businesses-self-employed/deducting-business-expenses

What Can I Deduct?

To be deductible, a business expense must be both ordinary and necessary. An ordinary expense is one that is common and accepted in your trade or business. A necessary expense is one that is helpful and appropriate for your trade or business. An expense does not have to be indispensable to be considered necessary.

It is important to separate business expenses from the following expenses:

• The expenses used to figure the cost of goods sold,
• Capital Expenses, and
• Personal Expenses.

Possibly, but only the cost of the specific items used for business purposes.  And it goes without saying that you can only deduct these expenses on a schedule C if you are reporting your channel as self-employment income and paying the proper income tax and SE tax on the net profits.  (If you are declaring the income as "other" income and not filing a schedule C, you can't deduct any related expenses.)

If you are eating the food, I would say no.  Buying food is inherently a personal expense, even if it is connected to the business.

If you are giving the food away or throwing it away, yes, it is a deductible business expense.