Location: Food Science and Market Quality and Handling Research Unit
Project Number: 6070-30600-001-000-D
Project Type: In-House Appropriated
Start Date: Jul 7, 2025
End Date: Jul 6, 2030
Objective:
Objective 1: Examine the influence of genotype and post-harvest storage on quality of fresh and processed vegetables.
Sub-objective 1.A: Determine the influence of genotype and post-harvest handling on texture quality of cucumber pickles.
Sub-objective 1.B: Investigate the effect of phytonutrients and their thermal degradation products on sweetpotato flavor.
Objective 2: Determine the impact of the indigenous microbiota on texture quality of fermented cucumber pickles.
Sub-objective 2.A: Determine the cell-wall degrading potential of indigenous cucumber fermentation microbiota and develop mitigation strategies to enhance texture quality.
Sub-objective 2.B: Evaluate natural antimicrobials for inhibiting yeasts and molds that may be implicated in spoilage of cucumber pickles.
Approach:
Numerous factors can reduce quality and marketability of fresh and processed vegetables, leading to food loss and waste, economic costs, and decreased consumption of vegetable products. Flavor and texture of sweetpotatoes and pickled vegetables will be investigated to enhance quality and support commercial production of health-promoting foods. Pickled cucumber is particularly vulnerable to inconsistent texture quality, which reduces shelf-life and contributes to food waste. An industry-relevant model system will be developed for testing the effects of post-harvest handling on texture retention. Cucumber genotypes with different dispositions towards softening will be subjected to varying post-harvest handling regimes, pickled, and evaluated for firmness and cell wall polysaccharides (CWP). The data will inform best practices in post-harvest handling of pickling cucumber and identify CWP classes important for yielding high-quality pickle products with minimal losses. Concurrently, cucumber microbiota will be screened for tissue softening, polysaccharide-degrading enzymes, and anti-fungal activities. Selected microbes will be tested in laboratory systems to develop a model of fermented cucumber softening. Starter cultures and/or natural antimicrobials will be evaluated in low-salt fermentations to assess the ability to improve texture quality of fermented cucumber pickles. In sweetpotatoes, genotypes vary widely in contents of carotenoids and anthocyanins. These phytonutrients have been linked to health benefits, but little is known about the effects on flavor. Flavor profiles of cooked sweetpotatoes that vary in carotenoids, anthocyanins, and other phenolics will be determined by a trained sensory panel along with comprehensive phytonutrient and volatile compound profiling by mass spectrometry. Relationships between phytonutrients, volatile compounds, and flavor will be modeled using multivariate and machine learning techniques and validated in a model system. Linking sweetpotato phytonutrients to flavor would help breeders select new varieties and foster the development of consumer-preferred products with optimized phytonutrient content. Collectively, this research will increase availability and encourage consumption of vegetable products.