On Jul 12, 3:04*pm, "Michael O'Connor" > wrote:
> The thread about soy sauce and mustard sauce condiment packets got me
> to thinking how long they are good for? *I would guess Mayonnaise
> packets aren't good for very long. *Mustard and Ketchup packets
> probably last longer due to the acidic nature of them.

This is what I found out when I asked the Heinz Group:

Our coding information for these items is stamped on the outer cases
that are shipped to restaurants. Shelf life is based on the
production code. For best quality, we recommend that the following
items be used by the end of the shelf life shown:

Product Shelf Life

Single Serve Ketchup 7 months
Single Serve Chopped Onions 7 months
Single Serve Mayonnaise 8 months
Single Serve Relish 9 months
Single Serve Taco Sauce 9 months
Single Serve Tartar Sauce 8 months
Single Serve Yellow Mustard 9 months

Without code information, we are unable to determine the age of the
packet. If the packet appears puffy, bulging that could be an
indication of an old packet.