Research & Development
Emerald™ Sprout Machine (Patented) Science:
Why Conventional Rotary Sprouter And Cleaning Methods Are Inferior
"Raw sprouts present unique food safety problems because conditions under which they are produced--growing time, temperature, water activity, pH (a measure of acidity) and nutrients -- are ideal for the rapid growth of bacteria.If pathogens are present on or in the seed, these conditions are likely to encourage proliferation." (HHS News, 1999 October, published by US Dept. of Human Health Services --in pdf). "FDA believes that the seed is the source of contamination in most of the foodborn illness outbreaks associated with sprout consumption." ("Note to Firms that Grow, Condition, Store, or Distribute Seed for Sprouting and to Firms that Produce, Pack, or Ship Fresh Sprouts," Terry C. Troxell, Ph.D., FDA, 2004 August 19 --in pdf) "Microbiological analyses have shown that alfalfa seeds routinely contained high levels of microbial flora, including coliforms and fecal coliforms. Of even greater public health significance however, is the fact that pathogens can exceed 107 per gram of sprouts without affecting the appearance of the product." (Food Safety Network Technical Report #16, 2000 July --in pdf)
Unfortunately, sprouts have an inherent propensity toward proliferating pathogens as the following research results suggest: "Bacterial flora of sprouts were often two to ten logs higher than that observed in seeds. E coli O157:H7 inoculated onto alfalfa seeds was shown to reach 106 to 107 cfu/g within 48 hours after the sprouting process began. Additionally, low levels of Salmonella species seeded into alfalfa seeds have been shown to increase by as much as four to five log in germinating sprouts. Therefore, the contamination of seeds with a few pathogens can potentially be amplified by the sprouting process and become a microbiological hazard." ("Risks Associated With the Consumption of Fresh Sprouts," Sylvanus Thompsons and D.A. Powell, Food Safety Network Technical Report #16, 2000 July --in pdf)
So what is it with the conventional rotary drum or sprout cleaning methods that such hazardous pathogens are "amplified" by? The article above goes on to explain: "These excellent conditions for bacterial growth are further facilitated by the fact that the sprouting process has no inherent kill steps that either prevent bacterial growth or eliminate them entirely." ("Risks Associated With the Consumption of Fresh Sprouts," Sylvanus Thompsons and D.A. Powell, Food Safety Network Technical Report #16, 2000 July --in pdf) The "sprouting process" must mentioned implicates the conventional equipment and methods used in the industry as being inept -- even encouraging hazardous bacteria growth and proliferation. Consequently the industry’s serious problem with pathegons.
Emerald™ Purifier Sprouter machine offers a practical, effective means for eliminating such bacteria during and throughout the sprouting process by providing a virtual one-step procedure that is easy, requires less labor, is economical, yet is highly effective at killing the germs.
Conventional Rotary Sprouting Machine -- Part of the Problem
Rotary sprouting machines, as mentioned, are used by virtually every sprout business who commercially produces alfalfa, radish, broccoli, clover, onion, or similar sprouts. While these machines grow the sprouts, they do nothing toward disinfecting the product. Actually, they are part of the problem. Such machines merely maintain a wet damp environment that is conducive to growing both sprouts and, unfortunately, bacteria. It should be made clear, at this point, that such machines do not offer means for washing the sprouts nor a means for eliminating pathogens. Even if a disinfectant is injected into their spray water, the pathogen problem is far too set into the product for such superficial attempts to be effective.
Sprouts such as alfalfa, broccoli, and the like are tender and can survive only limited concentrations of disinfectant exposure. Furthermore, spray applications of such low levels of disinfectant solutions accordingly dictated are highly ineffective. Why is this so? While a limited number of bacteria may be eliminated by any such efforts, large numbers invariably survive and continue to thrive. Such pathogens can become highly resistant and even more difficult to kill as hours go by. Not only does the sprout mass provide an ideal environment for bacteria to grow, but there is also an abundance of building blocks of proteins and other nutrients in which bacteria can coat, burrow, and fortify themselves with. Certain foodborne pathogens encase themselves in their own protective biospheres which must be stripped away or penetrated in order to reach the bacteria burrowed inside. The longer such pathogens are permitted to perfect their biospheres, the harder they are to kill. Such germs can be killed but to do it effectively it takes more than what the conventional rotary sprouter can offer. This is especially the case considering the very limited concentration of disinfectant solution that sprouts can tolerate and survive. Even various surfactants have proven ineffective oxidizer complements. Furthermore, it is important to note that oxidizers cannot kill what they cannot contact intimately.
For non-biosphere bacteria, the proteins and organic matter surrounding them make them more difficult to wet with disinfectant. Also, the oxidizing power of any oxidant disinfectant is expended on the competing organic content of the sprout mass. These factors taken together make for a challenging problem -- again, one that conventional rotary sprouting machine cannot meet. The traditional rotary sprouter cannot offer a practical means for providing the aggressive and intimate wetting contact necessary to kill offending pathogens with the low concentrations of oxidizers such that the sprouts could survive. What is needed is persistent and repeated washings with low levels of disinfectant and with aggressive intimate contact of the disinfectant that is concurrent, frequent, and ongoing with the sprouting process. The conventional rotary sprouter has no practical means for accomplishing such inclusions. Therefore, for these reason and any number of additional reasons, all efforts or methods devisable within the conventional rotary sprouting machine have not, will not, and cannot solve the health-risks problems facing the sprouting industry today. Emerald™ Purifier Sprouter machine, however, offers a simple and practical means for effectively addressing all such issues as the disclosure herein will reveal.
Furthermore, the conventional "rotary sprouter" or "rotary drum" commonly consist of a cluster of four horizontal sprout chambers or quadrants mounted together on a horizontal axle. Each quadrant or growing chamber has an open front where a door is mounted for containing the seed and sprouts. The quadrants or chambers slope to the front toward the doors where the water can drain out around the doors. Adequate drainage is important to prevent water logging and subsequent deterioration of the sprouts.
In additional, conventional rotary sprouters generally have a fan mounted on a stationary plenum that feeds air into the rotary drum's growing chambers. The fan introduces and circulates fresh air in and through the growing chamber. Accordingly, the back side of the quads has air openings as does the doors in the front for the flow-through ventilation. A weakness in this prior art, however, is that screens are installed in these openings to prevent loss of seed and sprouts. These screens are unsanitary because the mesh openings are difficult to clean and sterilize without removing from the machine. Pathogen-infected screens can contaminate subsequent crops thus contributing to the health risk associated with sprouts. A feature within Emerald provides a means for retaining the product without any need for such screens thus enhancing sanitation.
Considering the foregoing, clearly the conventional rotary sprouter shares blame for the ineptness of the industry at producing sprouts that are free of borne-illness pathogens. Again, Emerald™ sprouting machine, provides key enhancements and changes that transform the rotary sprouter machine into a sprout washing machine that can propagate, wash, and disinfect the sprouts perpetually all in virtually one simple step.
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Other Conventional Sprout Cleaning Method: Use of Gamma Radiation
"Research carried out by the U.S. Department of Agriculture concluded that treating alfalfa seeds and sprouts with a combination of chlorine and irradiation effectively safeguards them against contamination by E coli O157:H7 and Salmonella. The report [from US. Department of Agriculture] further stated that the doses used to eliminate those organisms did not affect germination of seeds. However, the required irradiation dose is higher than the 1.0 kilogray dose allowed for fruits and vegetables. Further studies are required to confirm these preliminary reports." ("Risks Associated With the Consumption of Fresh Sprouts," Sylvanus Thompsons and D.A. Powell, Food Safety Network Technical Report #16, 2000 July --in pdf) Thus, currently treating "bad" seed and sprouts using gamma radiation is very unappealing. Furthermore, the level of public acceptance of irradiating a product that has traditionally bore a rather earthy organic health-food appeal is yet to be seen.
Other Conventional Sprout Cleaning Method: Heat Treatment of Seed "Limited Appeal"
US patent 6,415,547 B1 to Katsuyoshi Enomoto 2002 July 9 describes a method for sterilizing seed using heat. "Application of heat to kill pathogens on alfalfa seeds has been investigated in a study that found treatment at 57 or 60 degrees C for 5 minutes appeared to be effective in killing S stanley without substantially decreasing germability of seeds. However, heat treatment has limited appeal because there is such a fine threshold at which bacteria can be killed and germination not destroyed." ("Risks Associated With the Consumption of Fresh Sprouts," Sylvanus Thompsons and D.A. Powell, Food Safety Network Technical Report #16, 2000 July --in pdf)
Other Conventional Sprout Cleaning Method: Chemical Treatment
According an article in Food Safety Network Technical Report #16, there are several studies done on the effectiveness of chemical treatment in eliminating pathogens on seeds for sprout production, including calcium hypochlorite, sodium hypochlorite, hydrogen peroxide, ethanol, and ozone. The effectiveness of any sort of a mere seed wash is greatly limited due to micro-cracks and crevices on and in the seed. The article says that no matter how lethal the treatment solution is, if the solution cannot reach the pathogens in the seeds, it cannot disinfect the seeds effectively. Therefore, even if there is any substantial reduction of the pathogens in the "bad" seeds, none of the chemical treatments can completely eliminate harmful organisms reside in the seeds. Referring to efforts toward disinfecting the seed the same article goes on to say, "Even if only a few organisms survive a seed treatment, they can grow to high levels during sprouting and contaminate the entire batch. Therefore, disinfection alone cannot be relied upon to ensure the safety of sprouts. The best results were obtained with the use of calcium hypochlorite; thus approval was granted for its use at 20,000 ppm." ("Risks Associated With the Consumption of Fresh Sprouts," Sylvanus Thompsons and D.A. Powell, Food Safety Network Technical Report #16, 2000 July --in pdf)
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Other Conventional Sprout Cleaning Method: FDA Guidelines
"Despite the efforts by industry, government agencies,and academia to make sprouts safer, outbreaks continued to occur. It was therefore obvious that approved treatments, such as the routine use of seed disinfection treatment with 20,000 ppm of calcium hypochlorite, could not guarantee a safe product. This resulted in the FDA issuing new guidelines for the sprouting industry in October 1999." ("Risks Associated With the Consumption of Fresh Sprouts," Sylvanus Thompsons and D.A. Powell, Food Safety Network Technical Report #16, 2000 July --in pdf)
"The sprout guidance identifies a number of areas, from the farm to the sprouting facility, where FDA believes immediate steps should be taken to reduce the risk of sprout-associated foodborne illness. Specific recommendations in the guide include: development and implementation of Good Agricultural Practices and Good Manufacturing Practices in production and handling of seeds and sprouts; seed disinfection treatment; microbial testing before the product enters the food supply; and provision for trace-back. The guide recommends that seed should be subjected to one or more treatments that have been approved for reduction of pathogens on seeds and sprouts. This is to be followed by microbial testing of the spent irrigation water form each production lot to ensure that nay contaminated batch is not distributed. Test results before shipping products. The second document outlines the detailed procedures to be followed in implementing the testing." ("Risks Associated With the Consumption of Fresh Sprouts," Sylvanus Thompsons and D.A. Powell, Food Safety Network Technical Report #16, 2000 July --in pdf)
Still, it only stands to reason in the light scientific scrutiny and evidence that the FDA guidelines for disinfecting seeds and sprouts are not effective and will not be effective at getting rid of the foodborne illness problem associated with raw sprouts.
Conclusion: Emerald Advantage
The Emerald Sprouting Method provides key and practical enhancements that change and transform the conventional rotary sprout equipment from a germ paradise to an effective disinfecting washing machine. Emerald offers a simple, practical solution to the problem and is unsurpassed by any solution ever before devised. Furthermore, it offers additional benefits to the health of the sprout itself which encourages extended shelf life, market appeal, and added-value to sprouted products.
(Ask us about SprouBIOTICS for information on adding natural defense for your sprout--an optional feature of Emerald™ Rotary Drum & Sprout Purifier Machine)
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