In recent years, the surge in demand for plant-based proteins has transformed the landscape of food science and nutrition. While these proteins represent a sustainable and health-conscious alternative to traditional animal-derived products, their widespread acceptance has been hindered by off-putting odors that emerge during their cultivation and extraction processes. These malodors, often described with terms such as beany, grassy, earthy, sulfurous, or cereal-like, pose significant sensory challenges, particularly because smell is deeply intertwined with the perception of flavor. Without effectively addressing these sensory barriers, even the healthiest plant proteins risk being rejected by consumers.
A groundbreaking study spearheaded by researchers at Ohio State University has now delivered a promising solution to this persistent problem. By engineering a sophisticated, two-step fermentation protocol, the team has managed to remove between 95% to 99% of key unpleasant odors from a variety of plant-based protein sources. This represents a substantial advancement over previous methods relying on single-stage fermentation, which often yielded only partial odor reduction. Such a precise and efficient control of olfactory flaws could redefine consumer interactions with plant-derived protein products.
The science underpinning this breakthrough lies in the calculated application of microbial cultures. The initial stage exploits the metabolic activity of Lactobacillus plantarum, a well-characterized beneficial bacterium, to enzymatically catabolize odor-causing compounds within the protein substrates. This primary fermentation initiates the breakdown of foul-smelling chemicals such as volatile sulfur compounds and unsaturated fatty acids. However, fermentation processes can introduce or leave behind other aroma compounds that might not be ideal, which necessitates a subsequent refinement step.
To enhance the sensory profile and foster the formation of desirable aromas, the researchers implemented a secondary fermentation stage employing a traditional yogurt starter culture. This bacterial consortium, comprising strains commonly involved in dairy fermentations, is renowned for its capacity to generate complex and appealing aromatic molecules, including lactic acid and various esters. The synergy between these two fermentation stages creates a controlled biochemical environment that not only neutralizes negative odors but also enriches the flavor bouquet, shifting consumer perception favorably.
The team rigorously tested this sequential fermentation approach across eight distinct plant proteins, encompassing soy, pea, chickpea, mung bean, faba bean, rice, a barley-rice blend, and hemp. Sensory analyses utilizing trained human panels confirmed consistent and near-complete elimination of off-odors across all samples. This universality highlights the broad applicability of the method, indicating its potential to benefit a wide spectrum of plant-based food products, from drinks and snacks to meat and dairy analogs.
Importantly, this novel process does not extend fermentation times or introduce cost-prohibitive steps. Fermentation durations ranged from mere hours to a maximum of a full day, similar to industrial standards. By harnessing existing fermentation agents and modifying their application sequence rather than inventing entirely novel microbial strains or processes, the research easily integrates into current production pipelines. This practical aspect ensures scalability and keeps consumer prices unaffected, thereby easing market adoption.
Moreover, the study explored the influence of various additives common in food formulations on the fermentation efficiency and odor mitigation. For instance, the inclusion of allulose, a rare sugar, enhanced Lactobacillus plantarum activity, intensifying the initial breakdown of pungent compounds. Strawberry preserves, when introduced, appeared to support the secondary culture’s action, fostering richer aromatic complexity. Conversely, non-fermentable additives such as pectin, xanthan gum, and lipids had minimal impact on odor reduction, suggesting that the core microbial processes dominate the sensory transformations.
Beyond sensory benefits, this work carries significant implications for global food security and environmental sustainability. As the global population rises and ecological concerns mount, shifting dietary patterns toward plant-based proteins constitutes a critical strategy for reducing the agricultural footprint. By overcoming sensory barriers, the research promotes consumer acceptance of alternative proteins, which may lead to decreased reliance on resource-intensive animal agriculture. Furthermore, such innovations align with allergen-friendly and lactose-intolerant dietary trends, broadening accessibility.
The meticulous understanding of microbial metabolism and fermentation kinetics informing this study exemplifies how modern food science can tackle complex sensory issues without resorting to artificial flavor masking or chemical additives. Instead, leveraging biotechnological principles to steer microbial communities yields natural, health-aligned outcomes. This approach upholds the increasing consumer demand for transparency and “clean label” products free from synthetic compounds.
Looking forward, researchers anticipate continuous expansion of this two-stage fermentation methodology to encompass additional plant protein sources and food matrices. The versatility and efficiency demonstrated here lay a robust foundation for developing flavorful, nutritious, and sustainable food products that resonate with environmentally conscious consumers. As awareness intensifies and food innovation accelerates, such science-driven solutions will be pivotal in reshaping eating habits globally.
This study was recently published in the journal Foods, cementing its contribution within the scientific community. Lead author Manpreet Kaur, a doctoral candidate in food science and technology at Ohio State, emphasizes the method’s simplicity: “We are using the same things that are used in the normal fermentation process. The only thing changed is how we utilize the bacteria.” Co-author Sheryl Barringer further highlights that advancements in plant proteins are crucial as more people adopt vegetarian or reduced-meat diets without compromising on taste.
In sum, this innovative sequential fermentation system stands to revolutionize the plant-protein sector by systematically eradicating unwanted aromas that have long limited consumer enthusiasm. By synchronizing microbial expertise with food technology, the research achieved a practical, scalable approach to enhancing the sensory appeal and market potential of plant-based proteins, heralding a new era of sustainable nutrition.
Subject of Research: Off-odor removal in plant-based proteins through sequential microbial fermentation.
Article Title: Controlling Off-Odors in Plant Proteins Using Sequential Fermentation
News Publication Date: 23-Dec-2025
Web References:
Journal Foods: http://dx.doi.org/10.3390/foods15010039
Lactobacillus plantarum information: https://www.webmd.com/vitamins/ai/ingredientmono-1672/lactiplantibacillus-plantarum
Environment and sustainability context: https://gfi.org/resource/environmental-impacts-of-alternative-proteins/
Global food security and plant-forward diets: https://www.theclimategroup.org/our-work/news/why-plant-forward-diets-are-key-global-food-security
Keywords: Foods, Food additives, Food science, Agriculture, Food production, Environmental sciences, Plant sciences, Plants, Legumes, Strawberries
Tags: addressing malodors in plant proteinsadvancements in protein extraction methodsconsumer sensory perception of plant proteinsengineering fermentation protocolsfermentation technology for odor removalhealth benefits of plant-based dietsimproving flavor profiles of plant-based foodsmicrobial cultures in food processingOhio State University researchplant-based protein researchsensory challenges in food acceptancesustainable food science innovations
