A challenge for growing fresh foods (vegetables) in space is demonstrating that they are safe for consumption according to NASA microbiological standards set for food. The goal of this project is to select and advance methods to enable real-time sampling, microbiological analysis, and sanitation of crops grown on the International Space Station (ISS). These methods would validate the microbiological quality of crops grown for consumption to ensure safe and palatable fresh foods. This will be achieved through the development / advancement of microbiological sample collection, rapid pathogen detection, and effective sanitation methods that are compatible with a microgravity environment.
This project aligns with current plans for deployment of a vegetable production unit on the International Space Station (Veggie) and the procurement and evaluation of platforms (RAZOR) at Kennedy Space Center for rapid microbial monitoring on ISS.
A 3-step approach is being used to evaluate and modify methods for analyzing fresh produce (fresh vegetables / fruits) that would be compatible with a microgravity environment. Candidate food crops are being grown in a controlled environment chamber for the following tests:
A series of experiments has been completed using three different sampling procedures, swabbing, adhesive tape collection and sample blending for the recovery of bacteria from the surface of radish, tomato and lettuce. Data collected and analyzed to date show no significant difference using culture based detection methods between the adhesive tape and bag blender sample methods in the recovery of Salmonella enterica Typhimurium, a human associated food borne pathogen inoculated onto the surface of lettuce, tomato, and radish. The swab method recovery was significantly lower then the other two methods in the case of lettuce and radish. With the samples collected by these different sampling procedures we are comparing detection and quantification methods, specifically real-time quantitative polymerase chain reaction (q-PCR) using two platforms, the LightCycler® (Roche Diagnostics) and a rapid portable system, the RAZOR (Biofire, Salt Lake City, UT) with conventional culture based methods. For these tests we used S. enterica Typhimurium and Eshcerichia coli K12 inoculated onto the surface of red leaf lettuce and radish. We were able to detect S. enterica from 5/5 samples recovered from radish. This rapid method would eliminate the need for plating onto media or DNA extraction followed by real-time quantitative polymerase chain reaction (RT-qPCR) shortening detection and enumeration time from 12-48 hrs to approximately 3 hours.
Two concentrations of sanitizer-saturated wipes were tested to lower the microbial counts on radish, tomato and lettuce and plastic surfaces similar to the materials that comprise the Veggie plant growth system. The sanitizer was effective in lowering the bacterial count by 90- 99.9% on vegetable surfaces and up to 99.99% on plastic surfaces.More »
Methods specifically designed for quality assurance of fresh produce grown and consumed in space have yet to be defined. Currently, NASA astronauts cannot consume fresh foods grown in space. The need exists, as vegetable production units are being deployed on the the International Space Station (ISS). The Veggie plant growth unit, developed by Orbitec, was recently launched to the ISS and will be growing edible salad crops, and the Advanced Plant Habitat could also be used for future food production work.
These same capabilities developed for food production on the the International Space Station could be translated to future human exploration efforts, such as near-Earth object (NEO), Mars Transit, Lunar Surface, and Mars Surface missions.
Aerospace companies that have interests or aspirations for developing orbiting human habitats or transit vehicles could benefits from this research and technology development.More »
|Organizations Performing Work||Role||Type||Location|
|Kennedy Space Center (KSC)||Lead Organization||NASA Center||Kennedy Space Center, FL|
|LuminUltra Technologies Ltd.||International Organization|
|Microcide, Inc.||Industry||Troy, MI|