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Efficacy
of Electrolyzed Water in Eliminating Salmonella Enterica and Mechanism of
Enhancing its Uptake into Alfalfa Seeds
2002
Annual Meeting and Food Expo - Anaheim, California
Food
Microbiology: Fruits and Vegetables
Session
15D, 8:30 AM - 12:00 PM, Sunday, June 16, 2002
Presentation
15D-1
S.
Stan and M. A. Daeschel.
Food
Science and Technology, Oregon State University, 100 Wiegand Hall, Corvallis, OR
97331-6602
Alfalfa sprouts have been implicated in several outbreaks of salmonellosis in
the United States. Disinfection of seeds used for sprouting is difficult since
seeds may be wrinkled or present cracks that allow bacteria to be trapped within
the seed, where a water-based disinfectant cannot penetrate.
Therefore, a
mechanism of enhancing the uptake of the sanitizing agent into the seeds might
improve the disinfection step. We have hypothesized that exchanging the internal
gas of seeds with oxygen results in more absorption of a liquid-based
disinfectant into the seed. The electrolysis of water containing sodium chloride
imparts a strong oxidizing character to the water collected at the anode and
thus may be an effective seed disinfecting agent.
The objectives of this study were to evaluate the effectiveness of electrolyzed
water in killing Salmonella enterica Stanley in an aqueous system and to
determine the effect of the oxygen- exchange procedure on the absorption of
electrolyzed water into the alfalfa seeds.
Seeds (400 g) were exposed to oxygen at a flow rate of 1.5 liters/min for 1 hour
to exchange the internal atmosphere. A control was represented by non-exchanged
seeds. Anode electrolyzed (AE) water was obtained through the electrolysis of
water containing 0.05% NaCL.
Results indicated a higher uptake of electrolyzed water into the
oxygen–exchanged seeds as compared to the non-exchanged seeds. A soaking time
of 150 min in electrolyzed water reduced the germination of seeds by 17% while a
15 min soaking time did not affect the germination. In an aqueous system,
electrolyzed water was found to have a 5 log reduction effect on Salmonella
enterica Stanley after 15 min.
This study suggests that the combination of the oxygen gas -exchange procedure
with the use of AE water may be effective in reducing the population of
Salmonella enterica on alfalfa seeds.
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