I brush, floss, and rinse regularly. However, after lunch I do not have enough time to brush my teeth. What can I do to avoid bad breath?

Water, gum, diet. First, obviously, avoid known causes like onions, garlic and so on. Foods that are 'non-sticky' will not promote odors since they tend to be swallowed better. Chewing gum helps increase saliva to wash food and germs down; drinking water also helps. Gum with xylitol as a sweetener (found in some gums) will, in additon to helping breath, also help reduce cavities.

Related Questions

I floss, brush my teeth twice, use mouth wash & yet I have a bad breath. How can I avoid this once & for all? It's embarrassing. Thank you

Answer. See the dentist regularly twice a year for regular check up, most of the times early plaque or caries can cause bad breath. Then watch for foods that can cause bad breath like onions, garlic etc. To avoid public embarrassment keep mint gum or lozenges handy.
Several issues. This may be from reflux esophagitis, post nasal drip, gingivitis, or conceivably an esophageal diverticulum. A good place to start would be with your dentist. If there is no focus in the oral cavity, an ENT doctor would be my next step. This can be worked out successfully. Do not give up. Good luck and feel better.
Flora. You may also have a balance of odor causing bacteria in your mouth. Some of us have the cavity causing bacteria in our mouths and others gum disease causing. All this to say that if you are brushing your tongue way deep and are as religious as you say concerning your oral hygiene you may just be an unlucky soul. My kids keep their mouths very clean but still have halitosis. Natural oils may help.