Enhancing wheat muffin aroma through addition of germinated and fermented Australian sweet lupin (Lupinus angustifolius L.) and soybean (Glycine max L.) flour

Australian sweet lupin (Lupinus angustifolius L.) and soybean (Glycine max L.) are excellent plant protein sources, however undesirable legume flavor can be a barrier to greater consumption. The impact of germination and fermentation on the concentration of free amino acids and free fatty acids in lupin and soybean flour and on the aroma profiles of baked muffins containing germinated and fermented lupin and soybean flour (40% w/w) were evaluated by gas chromatography mass-spectrometry and olfactometry. Muffins incorporating germinated lupin and soybean flours had a higher concentration of selected free amino acids and most volatiles, followed by muffins enriched with fermented lupin and soybean, compared to wheat muffins. Based on olfactometry and semi-quantitative volatile data, muffins baked with the addition of germinated and fermented lupin and soybean flour were characterized by a higher concentration of odor-active volatiles and more intense aroma.