It is not safe to shorten canning time, especially with low acid foods such as beans.  Citric acid is not a recommended additive and adding it doesn't make it safe to shorten the processing time.  There are two different methods for rehydrating beans and you could try the other method from what you did to see if it makes a difference in the firmness of the beans.  Most canners rehydrate their beans by letting them soak 12 to 18 hours in a large pot covered with water.  The alternative is to cover beans with boiling water in a saucepan and boil for two minutes.  Then remove from heat, soak for one hour and drain.  Regardless of the soaking method you use, you do need to then cover the soaked beans with fresh water and boil for 30 minutes.  Fill hot jars with beans and cooking water leaving 1 inch headspace.  Pints need to be processed in a pressure canner for 75 minutes and quarts for 90 minutes.  The time is crucial to make sure the heat penetrates all the way into the very center of the jar and gets the temperature up to above 240 degrees F to kill the bacteria spores that cause Botulism.