Subject: Compost Tea Safety

From: [email-masked]
Date: Thu, 14 Nov 2002 12:45:43 EST

The suggestion by Douglas to incorporate HACCP into the production of compost
tea would be a step in the right direction, but may not be the ultimate
answer. There are significant differences between the theory and practice of
HACCP. If HACCP is applied and limited to the boundaries of a production
facility, the system may or may not work. The HACCP system works best if it
is implemented throughout the food chain. Meat processors have HACCP programs
but their suppliers (feedlots) may not. As a consequence, the quality and
microbial contamination of the incoming materials to the meat processing
plant may be very variable. Unless there is a kill step for pathogens (and
even then), the output from the plant will be dependent on the quality of the
incoming materials and the effectiveness of the meat plant's HACCP program.
In short, I am suggesting that we must more closely scrutinize the sources
and quality of materials used to make compost and compost teas. You can't
make a silk purse out of a sow's ear (I think that's the old saying?). For
example, proper composting ensures a reduction in pathogens. Can it achieve a
1 log, 2 log, 5 log, etc reduction? Can the starting pathogen load be high
enough that the expected X log reduction in pathogens leaves a residual load
in the finished product that is of concern?

We focus primarily on the methods used for producing compost teas. I think
that there should be an equal focus on the raw materials used for producing
compost teas. The methods that were used to produce the raw materials used
for making compost and compost teas must be scrutinized. I do not think that
it is possible to create composting and compost tea production systems that
can accommodate an infinite variability in the raw material quality. In
short, the HACCP concept may be useful, but only if it is applied from one
end to the other of the food production system. One of the problems that we
will face with this concept is that we may find a chicken and egg scenario.
In a predominantly non-organic food production system, it may be difficult to
find sufficient quantities of suitable materials to process for organic
farming inputs, especially for large scale organic farms.

Alan Ismond, P.Eng.
Aqua-Terra Consultants

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From: Douglas Hinds <[email-masked]>
Date: Thu, 14 Nov 2002 15:17:57 -0600

Hello Alan & other saneters following this interesting thread,

Alan said:

AI> The suggestion by Douglas to incorporate HACCP into the
AI> production of compost tea would be a step in the right
AI> direction, but may not be the ultimate answer. There are
AI> significant differences between the theory and practice of
AI> HACCP.

AI> If HACCP is applied and limited to the boundaries of a
AI> production facility, the system may or may not work. The HACCP
AI> system works best if it is implemented throughout the food
AI> chain.

That is also true of the audit trail used with organic food
production & distribution.

AI> Meat processors have HACCP programs but their suppliers
AI> (feedlots) may not. As a consequence, the quality and microbial
AI> contamination of the incoming materials to the meat processing
AI> plant may be very variable.

AI> Unless there is a kill step for pathogens (and even then), the
AI> output from the plant will be dependent on the quality of the
AI> incoming materials and the effectiveness of the meat plant's
AI> HACCP program.

AI> In short, I am suggesting that we must more closely scrutinize
AI> the sources and quality of materials used to make compost and
AI> compost teas.

AI> You can't make a silk purse out of a sow's ear (I think that's
AI> the old saying?). For example, proper composting ensures a
AI> reduction in pathogens. Can it achieve a 1 log, 2 log, 5 log,
AI> etc reduction? Can the starting pathogen load be high enough
AI> that the expected X log reduction in pathogens leaves a residual
AI> load in the finished product that is of concern?

So additional research is needed.

AI> We focus primarily on the methods used for producing compost
AI> teas. I think that there should be an equal focus on the raw
AI> materials used for producing compost teas.

AI> The methods that were used to produce the raw materials used
AI> for making compost and compost teas must be scrutinized.

AI> I do not think that it is possible to create composting and
AI> compost tea production systems that can accommodate an infinite
AI> variability in the raw material quality.

AI> In short, the HACCP concept may be useful, but only if it is
AI> applied from one end to the other of the food production system.

Very true.

AI> One of the problems that we will face with this concept is that
AI> we may find a chicken and egg scenario. In a predominantly
AI> non-organic food production system, it may be difficult to find
AI> sufficient quantities of suitable materials to process for
AI> organic farming inputs, especially for large scale organic
AI> farms.

AI> Alan Ismond, P.Eng.
AI> Aqua-Terra Consultants

Unlike ISO standards, HACCP standards are designed specifically for
food. Alan refers to meat, which is in fact the area in which HACCP
has bee applied the most, since the danger of bacteriological
contamination is greatest there.

However, HACCP systems do exist for fruit and vegetable (try running
<"fruit and vegetable"+HACCP> through a search engine) and probably do
for grains also.

I can't take issue with any of what Alan said above. HACCP is a
discipline I intend to study further and suspect that some benefit
will result from doing so.

As for it being "difficult to find sufficient quantities of suitable
materials to process for organic farming inputs" from off-farm
sources, perhaps standards for community based organic input
production can be developed and implemented. The standards will help
drive doing what's necessary.

Written standards may be part of what distinguishes Man from other
organisms (although I can't swear they don't have their own and in
fact suspect they do, probably better ones than ours), so perhaps
well grounded, complete written standards are needed to help put Man
back on track.

Douglas

.