The present disclosure relates to recombinant yeast host cells having (i) a first genetic modification for reducing the production of one or more native enzymes that function to produce glycerol or regulating glycerol synthesis and/or allowing the production of an heterologous glucoamylase and (ii) a second genetic modification for reducing the production of one or more native enzymes that function to produce trehalose or regulating trehalose synthesis and/or allowing the expression of an heterologous trehalase. The recombinant yeast host cells can be used to limit the production of (yeast-produced) trehalose (particularly extracellular trehalose) during fermentation and, in some embodiments, can increase the production of a fermentation product (such as, for example, ethanol).