What makes a person belch very sulfaric rotten egg smelling and tasting burps. sometimes without eating yet that day?

Burps: This can be a symptom of gerd (gastroesophageal reflux disease) or possible biliary tract dysfunction, like gallstones. Other possibilities are food intolerance or true sensitivity such as celiac disease. If this is frequent or persistent, see your family physician for an evaluation.

Oral hygiene: Reflux can indeed cause similar symptoms. But most etiologies of these symptoms are either a consequence of dietary factors or poor oral hygiene.