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NASA NTRS2017

FY 2017 Center Innovation Fund Annual Report - Highlights/Abstract section

This project evaluated the feasibility of low pressure cold plasma (CP) for two applications: disinfection of produce grown in space and sterilization of medical equipment in space. Currently there is no ISS capability for disinfecting pick and eat crops, food utensils, food production areas, or medical devices. This deficit is extended to projected long duration missions. Small, portable, cold plasma devices would provide an enhanced benefit to crew health and address issues concerning microbial cross contamination. The technology would contribute to the reduction of solid waste since currently crews utilize benzalkonium chloride wet wipes for cleaning surfaces and might use PRO-SAN wipes for cleaning vegetables. CP cleaning/disinfection/sterilization can work on many surfaces, including all metals, most polymers, and this project evaluated produce. Therefore CP provides a simple system that has many different cleaning application in space: produce, medical equipment, cutlery, miscellaneous tools.

plant growt↗

NASA NTRS2018

Baseline Microbial Assessment of Fresh Produce

Currently no standards or requirements exist for microbial food safety for space grown produce (fresh plant foods). Without standards it is difficult to assess produce handling and sanitization options for the ISS and future exploration missions. We are conducting a literature review of microbial levels on fresh food and then carrying out measurements (microbial counts) of grocery store purchased and controlled environment-grown crops. Testing will include lettuce, mizuna, cherry tomato, pepper, and radish, all candidate crops for pick-and-eat testing on ISS and near term exploration missions. Growth chamber conditions will be set to mimic an ISS or spacecraft environment. Assays will include specific pathogens (Enterobacteriacea, Salmonella sp., and Aspergillus flavus) and total culturable microorganisms using aerobic plate counts, and total yeast and mold counts. Analyses will follow the FDA Bacteriological Analytical Manual methods. The goal of the project is to establish a baseline for expected microbial levels found on fresh plant foods that might be grown on ISS and near term missions, and develop risk assessment and microbial safety recommendations for these types of fresh foods.

Hummerick, M. E.↗

NASA NTRS2018

Microbial Monitoring and the Risk of Infectious Disease Aboard the International Space Station

The International Space Station (ISS) is a semi-closed habitat in low Earth orbit with environmental conditions provided by an advanced life support system that controls temperature and recycles air and most of the potable water. The crew's activities, such as eating, sleeping, hygiene, and laboratory research, are performed in relatively close proximity. Research in the laboratory includes a myriad of experiments, including those with rodents, plants, and pathogenic microorganisms. Despite these conditions, in-flight monitoring of ISS indicates that the microbial diversity is similar to homes on earth. Accordingly, the crew is generally very healthy, however infectious disease does occur and potential routes of infection by obligate and opportunistic pathogens cannot be completely prevented. Determining the extent of this risk is further complicated, as microorganisms can alter their characteristics in response to spaceflight culture, as exemplified by the increase in virulence of the enteric pathogen Salmonella enterica Typhimurium during spaceflight compared to otherwise identical cultures grown on Earth. Taken together, these factors suggest a need for continued microbiological monitoring and research to understand and mitigate the risk of infectious disease during long duration missions.

Ott, C. Mark↗

NASA NTRS2018

Investigating Microbiome Differences Between Red Romaine Lettuce Grown from Sanitized and Unsanitized Seeds

The International Space Station (ISS) as an integral component for the discovery and development of advanced robotics, materials, communications, medicine, agriculture, and environmental science due to it currently being the world's only microgravity laboratory of its kind. Because the ISS is a contained system with confined quarters, much research has been undertaken to assess and diminish the number of microbiological risks associated with astronauts inhabiting the station for extended periods of time. Notable microbiological risk factors include drinking water, air, and food. As an avenue for both mental/emotional respite and a source of fresh produce for astronauts, a vegetable production system has been employed on the ISS. In order to understand the microbial risks involved with a "pick and eat" vegetable system on the International Space Station (ISS), this study aims to compare microbial differences between sanitized and unsanitized seeds by tracking and identifying seedborne microbes throughout the development of red romaine lettuce (Lactuca sativa)-a plant species that has already been grown on the ISS.

Polanco, Jonilee A.↗

NASA NTRS2019

Dwarf Tomato and Pepper Cultivars for Space Crops

Several dwarf tomato and pepper varieties were evaluated under ISS-simulated growth conditions (22ºC, 50% RH, 1500 ppm CO2, and 300 μmol m(exp -2) s(exp -1) of light for 16 h per day) with the goal of selecting those with the best growth, nutrition, and organoleptic potential for use in a pick and eat salad crop system on ISS and future exploration flights. Testing included six cultivars of tomato (Red Robin, Scarlet Sweet ’N’ Neat, Tiny Tim, Mohamed, Patio Princess, and Tumbler) and six cultivars of pepper (Red Skin, Fruit Basket, Cajun Belle, Chablis, Sweet Pickle, and Pompeii). Plants were grown to an age sufficient to produce fruit (70 to 106 days for tomato and 109 days for pepper). Tomato fruits were harvested when they showed full red color, beginning ca. 70-days age and then at weekly intervals thereafter, while peppers were grown until numerous fruits showed color and all fruits (green and colored) were harvested once at the end of the test. Plant sizes, yields, and nutritional attributes were measured and used to down-select to three cultivars for each species. In particular, we were interested in cultivars that were short (dwarf) but still produced high yields. Nutritional data included elemental (Ca, Mg, Fe, and K) composition, vitamin K, phenolics, lycopene, anthocyanin, lutein, and zeaxanthin. The three down-selected cultivars for each species were evaluated for sensory attributes, including overall acceptability, appearance, color intensity aroma, flavor and texture. The combined data were compared and given weighting factors to rank the cultivars as potential candidates for testing in space. For tomato, the ranking was 1) cv. Mohamed, 2) cv. Red Robin, and 3) cv. Sweet N’ Neat. For pepper, the ranking was 1) cv. Pompeii, 2) cv. Red Skin, and 3) cv. Fruit Basket. These rankings are somewhat subjective but provide a good starting point for conducting higher fidelity testing with these crops (e.g., testing with LED lighting similar to the Veggie plant unit), and ultimately conducting flight experiments.

Spencer, LaShelle E.↗

NASA NTRS2019

New Technologies for Enabling Food Production Beyond LEO

NASA has identified the need for robust and sustainable ‘Pick-and-Eat’ systems for supplementing crew diets with fresh leafy green crops in near-term LEO (Low Earth Orbit), cislunar, and lunar missions. Spaceflight plant growth systems have been primarily designed for conducting space biology studies, but these systems are not optimal for sustained food production. Improved water and nutrient delivery subsystems that do not use bulky and non-reusable media are needed for decreasing the mass of the food production system. Autonomous technologies for monitoring plant health and food safety are needed for ensuring that the food produced is suitable supplementing crew diets with fresh, nutritious salad crops. Improved plant imaging techniques used for high-throughput phenotyping can be leveraged for monitoring plant health. Near-real-time measurements of the microbial ecology of food production systems are needed for assessing food safety. Furthermore, newly identified plant species and cultivars with improved growth habits and contents of antioxidants, vitamins, and minerals when grown in spaceflight environmental conditions are needed. These improvements in food production technologies will enable the design of sustainable life support systems for manned exploration missions beyond Low Earth Orbit.

Monje Mejia, Oscar A.↗

NASA NTRS2016

Advances in Rodent Research Missions on the International Space Station

A Research platform for rodent experiment on the ISS is an essential tool for advancing biomedical research in space. The Rodent Research allows for experiments of much longer duration that experiments on the Shuttle. NASA’s Rodent Research (RR)-1 mission was successfully completed, including post-flight analysis and achieved a number of objectives including validation of flight hardware, on-orbit operations, and science capabilities that were developed at the NASA Ames Research Center. Briefly, twenty C57BL/6J adult female mice were launched on the SpX4 Dragon vehicle, which thrived for up to 37 days in microgravity. Daily health checks of the mice were performed during the mission via downlinked video; all animals were healthy and displayed normal behavior without any significant signs of stress. Behavioral analysis demonstrated that Flight and Ground Control mice exhibited the same range of behaviors, including eating, drinking, exploratory behavior, self- and allo-grooming, and social interactions indicative of healthy animals. The animals were euthanized and select tissues were collected from some of the mice on orbit to assess the long-term sample storage capabilities of the ISS. The data obtained from the flight mice were comparable to those from the 3 groups of control mice (baseline, vivarium and ground controls), suggesting that the ISS has adequate capability to support long-duration rodent experimentations. We recovered over 35 tissues from 40 RR1 frozen carcasses, yielded over 3200 aliquots of tissues, and distributed to the scientific community, including NASA’s GeneLab and scientists in the U.S. through Biospecimen Sharing Program via Ames Life Science Data Archive. Tissues were also distributed to Russian research colleagues at the Institute for Biomedical Problems. The expression levels of select genes including albumin, catalase, GAPDH, HMGCoA Reductase, and IGF1 were determined using RNA isolated from the livers by qPCR and no significant differences by one factor ANOVA were found between flight and ground control groups. In addition, some of the liver samples were subject to transcriptomics, epigenomics and proteomics. The data are now available to the scientific community through GeneLab’s open science data website. Since the RR1 mission, another long duration mission (Rodent Research-2) was completed on the ISS in 2015 in which 20 female C57 BL/6J mice were successfully maintained on the ISS for varying time points, with the last group of 5 animals being on-orbit for 54 days. This second Rodent Research flight expanded the program’s capabilities with the introduction of new technologies including blood collection and separation and bone densitometry scanning. Furthermore, we have continued to expand the ISS’s capabilities by running a series of ground-based verification testing using male mice. Our next step is to fly male mice for Rodent Research-4 on SpaceX-10 to study the effects of microgravity on bone healing and regeneration. It will be the first long-duration mission using male mice using Rodent Hardware. In addition, the number of mice will increase from 20 mice (on RR-1 and RR-2) to 40 for RR-4. When samples return to Earth, a number of tissues will be dissected from the frozen carcasses and select tissue samples will become available to the scientific community via BSP. Altogether, we have continued to expand our capabilities for performing long-duration missions on the ISS as emphasized in the National Research Council’s Decadal Survey released in 2011 and to maximize science return from each mission.

Choi, S.↗

NASA NTRS2019

Plant Microbiomes May Provide Vital Information to Plant Success

Plant associated microbiomes, the rhizosphere and phyllosphere, are composed of communities of bacteria and fungi that may be mutualistic or pathogenic. These communities have the potential to influence plant health and development and can affect plant growth. Crop plants are being investigated as a fresh and safe supplement to astronauts’ diet and it is critical to understand and characterize these microbial communities. Multi-species crops, Mizuna mustard (Brassica rapa var japonica), ‘Outredgeous’ red romaine lettuce (Lactuca sativa), and Waldman’s Green lettuce (Lactuca sativa) were grown in two Veggie units on the International Space Station (ISS) for three grow outs in various combinations of plant types. Upon harvest, plant and pillow samples were frozen and returned to Earth for analysis. Bacterial and fungal community analyses for plant leaf and root, as well as pillow components, wick and media, were completed using next generation sequencing with the goal of surveying the composition of the entire community and identifying any potential pathogens. Bacteria were identified using the 16S rRNA gene whereas, fungi were identified with the internal transcribed spacer (ITS). The community composition for these three crops was compared between crop types and between plant tissue types. It is vital to mission success for the short term and long term to add nutritious, safe to eat vegetables providing a supplement to the crew members’ dietary requirements as well as to develop planning for deep space missions as we reach for the moon and on to Mars. Veggie technology validation tests were supported by NASA’s Space Biology Program.

Khodadad, Christina L.↗

NASA NTRS2019

VEG-04: the Effects of Light Quality on Mizuna Mustard Growth, Nutritional Composition, and Organoleptic Acceptability for a Space Diet

Space crop production will be important in future long duration exploration missions to supplement the packaged diet with fresh bioactive nutrients. Plant care and the addition of fresh veggies to the diet may also have a role in astronaut well-being. Pick-and-eat salad crops are the best candidates for this near-term supplementation since they require minimal processing or preparation to add to meals. While light quality can strongly influence plant responses on Earth, the impacts of light quality on plant growth and composition in spaceflight remain unclear. The VEG-04 experiment uses two Veggie plant growth chambers on the International Space Station to simultaneously test different red: blue light ratios on the growth of Mizuna mustard, a leafy green salad crop. In addition to plant health and yield, the composition of key nutrients is assessed. Astronauts conduct on-board organoleptic evaluation of the fresh produce. Microbial food safety of returned produce is examined, and a Hazard Analysis Critical Control Point (HACCP) plan has been developed for this crop. VEG-04 consists of two experiments, one lasting 28 days with a single harvest, and the second lasting 56 days, with three cut-and-come-again harvests. These different scenarios provide an opportunity to test two production concepts, examine different fertilizers, monitor microbial changes over time for this crop, and assess potential impacts of interacting with plants on crew behavioral health and performance in spaceflight operations. In ground testing, plant growth was not significantly different across the different light treatments, however nutrient composition did differ significantly. Flight test results will be compared with ground data. This research was co-funded by NASA's Human Research Program and Space Biology in the ILSRA 2015 NRA call.

Massa, Gioia D.↗

NASA NTRSDate not supplied

Microbiological Analysis of Mizuna Grown in the Veggie Hardware to Define Critical Control Points and Ensure the Safety of Space Grown Crops

The Veggie facility on the International Space Station has been utilized as a “pick and eat” plant growth system to provide fresh produce for crew consumption. The VEG-04 experiments completed in 2019 examined the effect of red-rich and blue-rich light treatments on the growth of mizuna as well as harvest method and resulting yield. Analysis was performed on plant tissues and associated hardware to evaluate the influence of these experimental variables on the microbial population. VEG-04A plant pillows with pre-planted Mizuna mustard seeds were launched on SpaceX-16 in December 2018. The pillows were initiated, and a single 35-day harvest was performed. Veg 04B pillows were pre-planted with Mizuna seeds and launched on SpaceX-18 in July 2019, initiated and subsequently harvested at days 29, 43 and 58. The crew consumed approximately half of the produce, and the remainder was frozen and returned for analysis. Leaves, swabs, wicking material, substrate, and roots were processed and plated on media for the enumeration and isolation of bacteria and fungi. Isolated bacterial colonies were identified using Biolog Micro ID system or MicroSEQ16S rDNA sequencing technique. Fungal colonies were identified using the MicroSEQ D2 rDNA kit. Sample extracts were plated onto specialized media to identify Escherichia coli/coliforms, Staphylococcus aureus and Salmonella sp. Results indicate that bacterial and fungal counts were higher in plants grown in red-rich lightin VEG-04A, while the opposite was true in the Veg-04B third harvest. Microbial counts increased with the repeated harvest method used in Veg-04B. These data support the understanding of environmental and horticultural practices that can affect the microbiological quality of space-grown produce grown and aid in identification of critical control points for the development of a hazard analysis critical control point plan for ISS-grown crops. This research was co-funded by the NASA’s Human Research Program and Space Biology.

Mary E Hummerick↗

NASA NTRSDate not supplied

Legume Organoleptic and Nutritional Analysis

Long-duration missions beyond low Earth orbit will encounter challenges in maintaining adequate nutrition and acceptability in the food system. In situ production of fresh produce can supplement nutrients deficient in the stored diet. Currently there is a limited number of crops that can be reliably grown for space crop production. Recent challenges with Veggie plant growth technical demonstrations (i.e. Tokyo Bekana Chinese cabbage interveinal chlorosis and necrosis when grown under elevated CO2 (~3000ppm) and narrow-band LED lighting) have highlighted the necessity to conduct rigorous ISS-relevant crop screening on the ground. Additionally, crops must be selected to address specific nutritional deficits as identified by HRP, with an emphasis on having a large diversity of crops available to meet nutritional requirements and crew acceptability. A variety of crop types are necessary to address known nutritional deficits in the stored astronaut diet, to include leafy greens (vitamin C, vitamin K, potassium), tomatoes and peppers (vitamin C, potassium, lycopene), and legumes (vitamin B1).Legumes are being evaluated for biological performance and suitability under ISS-like environmental conditions as well as nutritional content and acceptability. Legumes are one of the few pick and eat crop types that is an excellent source of Vitamin B1.In FY21-22 Biological and Physical Sciences (BPS) is funding screening of 32 legume crop cultivars at KSC, 16 of which will be down-selected based on horticultural performance and informal taste testing for further horticultural assessment and analysis. HRP in FY21-22 is funding organoleptic and nutritional analysis of these 16 down-selected legume cultivars to determine the most promising candidates for future space applications. Nutritional analysis will include full elemental, proximate (fat, protein, calories, carbohydrates, ash), and vitamins B1, C, K. This new work is currently postponed due to Covid-19.

L E Spencer↗

NASA NTRSDate not supplied

Microgreens Food Safety Evaluation

Microgreens have been recently identified as a new type of pick and eat salad crop that can be utilized in space crop production systems. The majority of traditionally grown leafy green crops can be grown as microgreens, in addition to crops such as legumes (e.g. pea shoots), sunflower, buckwheat, most herbs, and corn, presenting hundreds of microgreen crop options. With a wide variety of flavors, exceptional nutritional density, short growth cycles (7-14 days), and unmatched volume optimization potential, microgreens present as an interesting option for sustainable production of nutritious and flavorful crops in space. The food safety aspects of microgreens have been investigated by USDA in recent years, however, an assessment for crew consumption purposes has not yet been conducted to capture the variety of microgreen cultivar types grown in spaceflight relevant environmental conditions and hardware that could be a part of the astronaut diet. Seed sanitation methods will be developed for each microgreen cultivar to sanitize the seed coat and ensure viable germination and plant growth. Food safety analysis will be performed on 24 different fast-growing cultivars of microgreens by performing aerobic plate counts (APC), fungal counts, and select pathogen screening of edible plant tissue before and after treatment with ProSan sanitizing produce wash. Additional avenues of investigation into microgreens food safety will be undertaken to understand impacts of plant height at time of harvest (able to be manipulated by light spectrum), seed density at time of planting, and role of blue light in food safety metrics of microgreens (n=6-12 microgreen cultivars tested, depending on variable). These findings will be included in the Space Crop Production Hazard Analysis Critical Control Point (HACCP) plan. This new work is currently postponed due to Covid-19.

M E Hummerick↗

NASA NTRSDate not supplied

Testing of the Veggie Vegetable Production System on the International Space Station

The Veggie vegetable production system has been flying on the International Space Station since 2014, with a second Veggie chamber added in 2017. Veggie is a simple, low power, flexible platform for space plant cultivation. Since 2014, over a dozen crop cycles have been conducted in Veggie. Primarily leafy green crops have been grown, and many of these have been used to supplement the crew diet. Flowers were also grown, and the seeds returned produced viable progeny. In addition to the crop plants, Veggie has been used as a platform for model plants grown in Petri dishes or custom magenta jar chambers. Other used have included algal culture and an education seed germination experiment. Science in Veggie has focused on the plant microbiome, the chemistry and food safety of space-grown produce, the impacts of light quality on crop growth, and the behavioral health benefits of cultivating and eating space crops. Veggie is allowing testing and maturation of NASA’s early-stage space crop production research in a relevant environment, and the lessons that we are learning from this research are helping to shape future exploration scenarios. This research was funded by NASA Space Biology and NASA’s Human Research Program.

Veggie↗

NASA NTRSDate not supplied

Testing of the Veggie Vegetable Production System on the International Space Station

Veggie↗

NASA NTRSDate not supplied

Power Quality Analysis for a High Voltage Power System for Urban Air Mobility Application

This presentation is for the AIAA Electric Aircraft Technologies Symposium (EATS).

Nuha S. Nawash↗

NASA NTRSDate not supplied

The Microbiology of Microgreens Grown in Controlled Environment Chambers under ISS Conditions

Microgreens have been identified as a new type of pick-and-eat salad crop that can be utilized in space crop production systems. The majority of traditionally grown leafy green crops can be grown as microgreens, in addition to crops such as legumes, sunflower, buckwheat, most herbs, and corn, presenting hundreds of microgreen crop options. Notably, microgreens are nutrient dense, high in beneficial compounds like antioxidants, Vitamins C and K, and exhibit a variety of desirable flavors and textures.The short growth cycles (7-14 days), low water requirements and volume optimization potential make them a viable option for sustainable production of nutritious and flavorful crops in space.The crop production team at Kennedy Space Center is investigating the food safety aspects of microgreens grown under spaceflight relevant conditions for crew consumption. Microbiological analysis and screening for potential foodborne pathogens was performed on over 20 varieties of microgreens that have demonstrated positive horticultural attributes.Additionally, a comparison of microgreens grown hydroponically under ISS environmental conditions and similar varieties from local markets was completed to collect baseline data on the microbial load on microgreens. In aneffort to improve microgreen quality, strategies to reduce the microbial load were tested, including bulk seed sanitization, harvest age, exposure to high blue light, and post-harvest chemical disinfection. The efficacy of a citric acid-based produce wash currently used for ISS grown produce and 1% H2O2were investigated at different exposure times for reduction in bacterial and fungal counts on a variety of microgreens. Limited log reduction was achieved depending on exposure time.Our testing also demonstrated that seed sanitization impacted microbial load on microgreens and systems.

Mary E. Hummerick↗

NASA NTRSDate not supplied

KSC to EDEN ISS: Outredgeous Lettuce Growth on the Passive Porous Tube Nutrient Delivery System (PPTNDS)

EDEN ISS is a controlled environment greenhouse established near the Neumayer Station III in Antarcticawith the mission to enable fresh crop production for the crew who are working in this remote location. EDEN provides a space to conduct plant biology and related research in a unique and isolated controlled environment (CE), while providing a platform to test developing methods relevant to long duration manned space missions. In 2021, Kennedy Space Center (KSC) scientist Jess Bunchek fulfilled a one-year mission at EDEN. During that time a variety of fresh crops were grown to record horticultural and microbiological data as well as provide the crew with fresh food to eat. One method for crop growth included an experimental irrigation system called the Passive Porous Tube Nutrient Delivery System (PPTNDS) which was developed at KSC as a microgravity-capable plant irrigation system designed to support Space Plant Biology investigations and/or crop growth during space missions. The PPTNDS was employed to grow Outredgeous Lettuce (OL) during two growouts at EDEN, (harvesting at Day After Planting (DAP) 61 and 63) and two growouts at KSC where plant growth and micro sample data were captured. This paper presents the data collected from the PPTNDS and compares it to growth on a Nutrient Film Technique (NFT) hydroponic system operated in the same environment. The result shows a system that grows OL at a reduced rate compared to the NFT system but uses less water and crew interaction to operate.

Jacob Torres↗

NASA NTRSDate not supplied

Food Acceptability, Menu Fatigue, and Aversion During the Sirius-21 Analog Mission

Spaceflight food systems are closed systems, meaning they are restricted to the variety and quantity of food launched within resource limitations of the mission. The acceptability of the food system has been linked to caloric intake and associated nutritional benefits. ISS crew members receive substantial personal food preferences (around 25% of their total intake) but have noted in debriefs that they would prefer more food variety and preference for the length of the missions and they tire of certain foods over six months. Limits on variety and personal preference are expected to increase as missions become further from Earth. It is possible that menu fatigue leads to decreases in acceptability and increased aversion to available foods that may contribute to the body mass loss often experienced by spaceflight crews. However, the impact of repeat food consumption on acceptability has not yet been systematically investigated across potential spaceflight food systems. Limited variety and crew preferences within food categories may have more severe physical and behavioral health and performance consequences as mission duration increases. Characterizing the relationship between food acceptability and mission duration will contribute to defining requirements for an acceptable food system that will support crew health and performance on long duration missions. This study evaluated acceptability of the food system used in the SIRIUS-21 8-month mission in Moscow, Russia. To capture in situ scoring of repeat consumption experiences, we administered a weekly food acceptability questionnaire to all 5 crewmembers throughout the mission. Crewmembers scored foods they consumed at 3 meals every 6 days on a 9-point hedonic scale and provided open-ended feedback regarding food context, attributes, and the meal. The sequence was intended to capture all days in the 7-day menu cycle. The repetition was intended to target repeat food ratings that may provide insight into onset of menu fatigue where they might stop eating some foods or limit their choices to their favorites. Every 30 days crewmembers completed two additional surveys to characterize the food system, any changes to the food system, and their experience with the food system. Data collection is complete. Data are currently being assessed by descriptive statistics and visualizations of the ratings over time. The primary goal is to look for trends in the trajectories of ratings of the food items over time – both within and between individuals – to determine if there are substantial decreases in acceptability across all foods, or within specific food categories (e.g., vegetables). The number of times a particular item is scored provides some information on the frequency of consumption (preference), and the overall number of unique items can give a measure of overall variety. We will assess whether individuals were more likely to have more observations on food items that are rated higher, and whether those who rated foods higher had more or less overall variety. Since the data are composed of longitudinal subjective ratings, repeated measures techniques will be used to quantify trends over time and how these may relate to preference and variety. We will assess how these trends relate to their characterization of and experience with the SIRIUS-21 food system. We will also provide content analysis of any additional feedback collected on the open-ended questions and debrief interviews.

Grace L. Douglas↗