Do I have a lawsuit against a company for finding an object in my jar of food if there was no physical injury?

You can always sue anyone for anything at any time. However, the purpose of a civil judgment is to compensate you for damages that you actually suffered. You might have a case, but you are not likely to win very much if there was no injury.

Yes you have a lawsuit. Most suits like this are handled on a contingency basis. On these damages you would likely have to pay an attorney a high hourly rate to prosecute it for you. You might be better served going through customer service for free or alternate products.

What economic damages did you suffer? That is what drives our civil personal injury and negligence system. You would be MUCH better off in contacting the company and see if they would provide you with financial compensation so that this error by them does not get publicized. A lawsuit would not be financially worthwhile and most attorneys (all that I know of) would refuse to take it on a contingency fee basis because of the lack of damages.