Evaluating the impact of cultivar and processing on pulse off-flavor through descriptive analysis, GC-MS, and e-nose

Authors: PONSKHE, KAVERI - Michigan State University; DUBOIS, AUBREY - Michigan State University; TOWA, LILI - Michigan State University; HOOPER, SHARON - Michigan State University; Cichy, Karen; MAYHEW, EMILY - Michigan State University

Submitted to: Journal of Food Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/23/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Pulse consumption, including dry beans and chickpeas is low in the U.S., with 83% of Americans consuming pulses below the recommended intake of 2.5 cups/week. A potentially effective strategy for increasing consumption is to incorporate pulse flours into products traditionally made with wheat flour, such as pasta or crackers. However, sensory challenges, especially off-flavors, limit their sustained adoption. These off-flavors, often described as “beany,” include sub-character notes such as musty, earthy, and green aromas. Volatile organic compounds responsible for off-flavors can be minimized through cultivar selection and processing optimization. Combining instrumental analysis with human sensory evaluation was conducted in this study on bean and chickpea flours and porridge products made from the flours. Sensory and volatile differences across cultivars and processing methods were observed using a trained sensory panel and two instrument methods: gas chromatography mass spectrometry (GC-MS) and fast gas chromatography (electronic nose). The sensory and volatile profiles changed when flour was roasted and pulses were boiled. The electronic nose successfully captured key beany flavor markers, aligning with sensory findings better than targeted GC-MS, demonstrating its potential as a predictive tool for flavor profiling in pulses. The findings provide a foundational understanding of how cultivar selection, heat processing, and volatile composition influence the sensory quality of pulses.

Technical Abstract: Pulses are nutrient-dense and have a low carbon and water footprint but remain underutilized in the United States. A potential strategy to boost pulse consumption involves milling pulses into flour and incorporating them into convenience products traditionally made from wheat flour. However, addressing off-flavors—commonly described as beany, green, musty, or vegetative—is essential for sustained adoption. This study evaluated the impact of cultivar selection and processing methods (boiling, roasting) on off-flavor reduction in eight pulse cultivars using Descriptive Analysis (DA) and rapid volatile profiling with gas chromatography-mass spectrometry (GC-MS) and electronic nose (e-nose). DA revealed significant differences (p < 0.05) across cultivars and processing treatments for 20 sensory attributes, with roasting reducing green/vegetative and earthy/mushroom/musty off-flavors but increasing beany characteristics, especially in roasted navy bean flour. We identified 8 key volatiles via GC-MS, including ketones, aldehydes, and alcohols that were strongly correlated to vegetative and mushroom flavors. However, GC-MS had limitations in predicting beany off-flavors, likely due to the chosen targeted analytical approach. In contrast, the untargeted e-nose approach effectively distinguished non-roasted and roasted flours, identifying discriminant ions that correlated with sensory attributes like toasted and beany odors. E-nose data aligned better with DA results, highlighting its potential as a first screening tool for rapid flavor profiling. Findings highlight the importance of refining pre-treatment methods and selecting cultivars with milder flavors. E-nose and GC-MS can be used to optimize the sensory quality of pulse flour, supporting increased consumer acceptance of pulse-based products.