Kentucky State University
Acidic Electrolyzed Water Reduced Microbial Load on Vegetables Grown Hydroponically in Fish Ponds
Institution
Kentucky State University
Faculty Advisor/ Mentor
Lingyu Huang; Cecil Butler
Abstract
Aquaponics is gaining popularity for production of vegetables and fish. Water used for fish culture tends to be relatively high in microbial load, and it may contaminate vegetables during production and distribution of vegetables. The objective of this study was to determine the effects of rinsing with acidic electrolyzed water on the microbial load of vegetables grown hydroponically in fish ponds. Basil and butter head lettuce were grown on a foam raft floating in fish ponds. Edible portion of basil and butter head lettuce were cut into 1 cm length with sterilized scissors and mixed thoroughly before 10 g of the sample was homogenized with 90 mL of peptone water for 2.5 min in a Stomacher bag. One mL of the homogenized sample was inoculated onto Petrifilm plates for total aerobic count and E. Coli/Coliform, respectively, after 10, 100, and 1000 times of dilution. Plates were incubated in a culture chamber at 32 °C for 24 hr before the colony forming units were counted. Separate samples, taken from the same pooled sample, were rinsed with tap water or acidic electrolyzed water for 5 min in a plastic container. After the rinsing water was drained off, the rinsed samples were analyzed in the same way as described for the unrinsed samples. Tap water rinse reduced microbial load of basil leaves by 40% and rinse with acidic electrolyzed water lowered it by 60%. For butter head lettuce, tap water rinse reduced the microbial load by about 90% and rinse with acidic electrolyzed water lowered it by 98%. These results indicated that it was more difficult to reduce microbial load of basil leaves than that of butter head lettuce leaves. Rinsing with acidic electrolyzed water was more effective than tap water in cutting down the microbial load of vegetables produced hydroponically in fish ponds.
Acidic Electrolyzed Water Reduced Microbial Load on Vegetables Grown Hydroponically in Fish Ponds
Aquaponics is gaining popularity for production of vegetables and fish. Water used for fish culture tends to be relatively high in microbial load, and it may contaminate vegetables during production and distribution of vegetables. The objective of this study was to determine the effects of rinsing with acidic electrolyzed water on the microbial load of vegetables grown hydroponically in fish ponds. Basil and butter head lettuce were grown on a foam raft floating in fish ponds. Edible portion of basil and butter head lettuce were cut into 1 cm length with sterilized scissors and mixed thoroughly before 10 g of the sample was homogenized with 90 mL of peptone water for 2.5 min in a Stomacher bag. One mL of the homogenized sample was inoculated onto Petrifilm plates for total aerobic count and E. Coli/Coliform, respectively, after 10, 100, and 1000 times of dilution. Plates were incubated in a culture chamber at 32 °C for 24 hr before the colony forming units were counted. Separate samples, taken from the same pooled sample, were rinsed with tap water or acidic electrolyzed water for 5 min in a plastic container. After the rinsing water was drained off, the rinsed samples were analyzed in the same way as described for the unrinsed samples. Tap water rinse reduced microbial load of basil leaves by 40% and rinse with acidic electrolyzed water lowered it by 60%. For butter head lettuce, tap water rinse reduced the microbial load by about 90% and rinse with acidic electrolyzed water lowered it by 98%. These results indicated that it was more difficult to reduce microbial load of basil leaves than that of butter head lettuce leaves. Rinsing with acidic electrolyzed water was more effective than tap water in cutting down the microbial load of vegetables produced hydroponically in fish ponds.