I am sorry to say this, but, Never try to test your own foods. There is no foolproof way to test your own foods. Please, leave that to the food safety scientists in labs. Then, the number one guidline is never can your own recipes. This is a cooking recipe from a book. Canning and cooking recipes are not the same.
There are plenty of safe preserving recipes to chose from. You can find a recipe that will be similar and known to be safe.

Agree with Linda Lou. Your recipe may be safe or it may not. There is simply no way to know. Plus processing time would be nothing more than a guess.

The big concern is that in many recipes pH doesn't remain stable over time on the shelf so it has to be very acidic from day one. This one is quite low in acid when compared to approved Mango Chutney recipes.

Dave

Here is a link that might be useful: NCHFP - Mango Chutney

You could freeze it though!

I totally agree with Linda and Dave on the canning.
Always better safe than sorry.

Deanna

If you look into the government guidelines for canning for resale, you'll find this is exactly how boutique commercial canning operations can: By testing the acidity level of their canned goods. Grab yourself a copy of "Putting Up" or "Putting Up More." The author, a former commercial canner, explains the technique.

boutique commercial canning operations can

True but they have also already had their recipes (any that will be offered for sale) professionally tested by FDA labs and approved and their kitchens inspected, tested, certified and approved, and had special training.

So the two situations don't equate.

Dave