Actually the sugary foods start to ferment because of bacteria that was already present in the foods. Then, the bacteria have their fuel and produce gas, acid etc. A man by the name of Dr. Donsbach wrote books/pamphlets (from California). My baby had extreme gas after eating sugar (fruits) and dinners with protein at the same meal. He said don't, and to separate foods. This saved me much anguish as sugar dissolves in three to four hours and protein in six to eight hours. So I gave her dessert a few hours after dinner as stomach acids in action enough prevented bacteria from hurting.