I want to test my own food - where do I start

[Philippo Möller]

Hello

I live in a third world country and it seems like there is no bio hack community here. I am concerned about food and drinks I am buying and consuming here on a daily basis. I do not trust the food safety authorities here. For example, there are rumors here that diary products in the stores are not made from milk but from palm oil. I would like to test such things myself. Furthermore, I am conscious about excessive use of antibiotics in meat and vegetable production. Is it possible to test such things myself?  What about pesticides? What about other poisons and pollutants that might end up in food products?

Basically I would like to test all of my food before I consume it. I am willing to invest time in studying the subject and I am also happy to build a little home lab. I'm also planning to publish my findings for other people in my country to read.

So where do I start? Are there any good websites? When I google "food testing at home" all I get are pages for food intolerant people. I am looking for a website with instructions on how to perform tests and what equipment I will need to buy for my lab.

Any help would be greatly appreciated and I am sure this question has been answered somewhere already but I couldn't find it.

[Heather Dewey-Hagborg]

Great question +1

--
-- You received this message because you are subscribed to the Google Groups DIYbio group. To post to this group, send email to diy...@googlegroups.com. To unsubscribe from this group, send email to diybio+un...@googlegroups.com. For more options, visit this group at https://groups.google.com/d/forum/diybio?hl=en
Learn more at www.diybio.org
---
You received this message because you are subscribed to the Google Groups "DIYbio" group.
To unsubscribe from this group and stop receiving emails from it, send an email to diybio+un...@googlegroups.com.
To post to this group, send email to diy...@googlegroups.com.
Visit this group at http://groups.google.com/group/diybio.
To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/5159e0c4-7fad-4fa5-90aa-7cdb86466bcc%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

--

Heather Dewey-Hagborg

www.deweyhagborg.com
@hdeweyh

[Otto Heringer]

Hello Philippo,

the good thing about do this kind of work in underdeveloped or developing countries is the ease of good impact you may cause alone doing relatively simple sutff. Particulary I see it as an open field of good things to do. :)

I was looking for similar food tests some time ago and started this thread. But the kind of analysis was oriented to biocontamination or "biofraud" and not chemical analysis. At the time I got stuck on correct keywords in searching, but the forum solved this problem. Anyway, just FIY, take a look on this paper that might be useful.

In a quick search, the papers doing this kind of milk analysis use gas chromatography. So, to simply analyse the milk I would try a fractional distillation (this might be useful) and analysis by infrared spectrometry (I think someone here already mentioned that is building a DIY one) of the distilled products.

Good luck on your project!

To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/CAHxgum16ZjCLpdGXxkAvNdB-9M7Yr0GzBnZ68ap0iDj-oyavAw%40mail.gmail.com.

[Nathan McCorkle]

Can you tell us what country you're in? It can help determine what the
best path forward might be, from a supply-chain standpoint, legal,
etc...

The answer to your question lies largely in the domain of chemistry
and physics. You need to figure out how to determine naturally present
chemicals from the non-naturally present chemicals. For example, milk
fat vs palm oil: these are likely to be mostly the same chain-length
(number of carbons in the oil molecule chain) but probably differ
slightly in their populations (maybe milk fat has mostly 16 carbons,
but some percentage of 14 carbon molecules too... while palm oil is
mostly 16 carbon molecules, with some percentage of 18 carbon
molecules). Along with the chain-length population differences, which
way the molecule is bent at each carbon could be slightly different.
It is much easier to distinguish chains of different length which all
have the same bending configuration, than it is to distinguish between
chains of different length with different bending configurations...
for example... with simple techniques (bending configuration aside,
the chain-length largely determines the melting/solidification point).

So when you move on to other molecules... searching antibiotics
amongst all the tens/hundreds of thousands of different molecule types
floating in all the cells of the food you buy... you can see the task
is HUGE.

You have to be very clever (for example, some very powerful machines
use very smart and beautiful solutions to extract data and make sense
of it, often these use tools or data-processing based on complex math)
, or very patient.... or usually both.

Personally, I think there are some common-sense techniques that you
could start applying now, to avoid food that is worse quality...
without investing in equipment, rather spending time learning about
which foods are more susceptible to contamination to begin (i.e. sweet
fruits tend to have heavier pesticide use). Also humans have an immune
system and other ways to deal with toxicity... so for example if you
wanted to have a baby and raise it, the food the mother consumes
during pregnancy and while nursing, and the food the baby receives in
general the first few years... is much more important to be concerned
with. After early development, humans are much more able to defend
against bad chemicals and infections.

If you really want to get into equipment... I recommend learning
about: UV/Vis spectrophotometry, FTIR, Gas-Chromatography, Mass
Spectrometry, Raman spectrophotometry, Thin-layer chromatography,
fractional distillation, redox indicators, ELISA, antibiotic
susceptibility assays, PCR... and as many related topics as you come
across.

Cheers!
-Nathan

> --
> -- You received this message because you are subscribed to the Google Groups
> DIYbio group. To post to this group, send email to diy...@googlegroups.com.
> To unsubscribe from this group, send email to
> diybio+un...@googlegroups.com. For more options, visit this group at
> https://groups.google.com/d/forum/diybio?hl=en
> Learn more at www.diybio.org
> ---
> You received this message because you are subscribed to the Google Groups
> "DIYbio" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to diybio+un...@googlegroups.com.
> To post to this group, send email to diy...@googlegroups.com.
> Visit this group at http://groups.google.com/group/diybio.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/diybio/5159e0c4-7fad-4fa5-90aa-7cdb86466bcc%40googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.



--

-Nathan

[djwr...@gmail.com]

Along those lines, it's tough to be downhill of a field doused with pesticides.

http://www.theguardian.com/us-news/2015/aug/23/hawaii-birth-defects-pesticides-gmo

> To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/CA%2B82U9KgQCK3isCPnUwJHT%2B5-51UUX-%2Bu%3DfioA0FkpgRkRyoQQ%40mail.gmail.com.

[Cathal (Phone)]

I only need to see the website and the headline stub to know that article's nonsense.

Not meaning to be rude, but don't trust newspapers in general and particularly Mother Jones or The Guardian with science, or facts about Agriculture or Nutrition.

--
Sent from my Android device with K-9 Mail. Please excuse my brevity.

[Daniel C.]

I think you'll find that this group is not sympathetic to the anti-science position in that article. GMOs substantially reduce pesticide use and genetic engineering has been consistently shown to be a perfectly safe technology.

On the flip side, organic farming uses pesticides that are far more dangerous to humans.

To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/16123033-3E89-405E-BFB2-FC2841EBF679%40gmail.com.

[Nathan McCorkle]

On Mon, Aug 24, 2015 at 3:57 AM, Daniel C. <dcroo...@gmail.com> wrote:
> I think you'll find that this group is not sympathetic to the anti-science
> position in that article. GMOs substantially reduce pesticide use and
> genetic engineering has been consistently shown to be a perfectly safe
> technology.

To be fair, I think, that article seems to be more about outdated and
grandfathered-in laws about chemical discharge, and the discharge
being in close proximity to a school and hospital. The main theme is
that on these islands the companies test GMOs... so it does make some
sense that they would use higher amounts to have strong selection
during breeding and development. It mentioned some possible connection
with similar birth defects in areas of chemical application (or
synthesis factories, I'm not sure) on the mainland, but it didn't seem
to cite anything about that. I am not sure how much credibility such
studies have behind them.

The article really didn't complain much/at-all about GMOs, as far as I
could tell, aside from the significant pesticide application during
their development process.

[Jonathan Cline]

On Monday, August 24, 2015 at 3:57:20 AM UTC-7, Dan wrote:

  genetic engineering has been consistently shown to be a perfectly safe technology.

There are no long term studies which prove genetically engineered food products are safe.  Your statement is a dangerous one.  "Long term" is defined in relative terms to a human lifespan which is what it would require for a proper medical study today.   Science can't even decide simple questions, such as, to what degree sugary drinks are harmful to health.  It's naive to think that sweeping changes in agriculture are harmless by default when science is not yet anywhere close to fully understanding microbes in the human gut.  Science has no idea what happens when people eat genetic engineered product other than that they seem to not die quickly afterwards.  That adjective phrase "perfectly safe" is a ridiculous assumption.  DIYbio groups especially should be more clued-in to the political/economic biases of science which might make such statements seem plausible.

Note. I am not anti-GE.  I am anti-"just be naive and hope for the best and when it all turns bad just deny any knowledge or involvement".


## Jonathan Cline
## jcl...@ieee.org
## Mobile: +1-805-617-0223
########################

[Bryan Jones]

The great thing about the DIYbio movement is the possibility for diversity. If you are worried about eating transgenic foods you don't need to lobby your congress critter for mandatory labeling or write a RO1 grant to do a placebo controlled human study. Thanks to groups like this and cheap/open source hardware that is becoming available, you can test the food yourself. Build a thermocycler and test for the presence of the CP4 EPSP synthase gene in your food.

I might think you are silly for worrying about the insertion of a single transgene when traditional breeding does orders of magnitude more mucking about with the genome, but it doesn't matter what I think if you have the power to take your food into your own hands.

[Vincent Danos]

 

great discussion!

Would you think there is a way to harness the worries and suspicions of some of the more

scientifically minded anti-GMO people

to organise a long term collective experience to quantify the problem

in a scientifically meaningful way?  

[Daniel C.]

Anyone sufficiently "scientifically minded" should have already found the thousands upon thousands of studies, performed over the past 20+ years, which have failed to demonstrate any harm from consuming GMO foods.

Oh, and that's just the studies funded by the EU, which is politically slanted against genetic engineering. So if there's any bias there it would go against the findings, not toward them.

--
-- You received this message because you are subscribed to the Google Groups DIYbio group. To post to this group, send email to diy...@googlegroups.com. To unsubscribe from this group, send email to diybio+un...@googlegroups.com. For more options, visit this group at https://groups.google.com/d/forum/diybio?hl=en
Learn more at www.diybio.org
---
You received this message because you are subscribed to the Google Groups "DIYbio" group.
To unsubscribe from this group and stop receiving emails from it, send an email to diybio+un...@googlegroups.com.
To post to this group, send email to diy...@googlegroups.com.
Visit this group at http://groups.google.com/group/diybio.

To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/bb65a401-c3aa-4e7f-ae02-ce3e1b719e2b%40googlegroups.com.

[Jonathan Cline]

You can test GE food yourself however it is still financially out of reach for the pro consumer considering the continual need for tests.  It would be easier if food were simply labelled properly.

To Philippo, you should perhaps try categorizing the types of harm and see which are important for you depending on where you are, and only after that, can you decide on protocols and equipment.   For example:  water testing (most important),  chemical (pesticides and insecticides but also, chlorine, fluorine, iodine),  metals and related (mercury, lead, arsenic), small organisms (like cysts), microbial, purposely fraudulent additives (plastics and large molecules), least importantly GMO testing.  Some crazy things the 1st world doesn't worry about:  Is DDT used in your region?  Are common insecticides sprayed everywhere including on meat and fruit?   (Rural farmers generously spraying cans of RAID over food in their stalls at local markets.)  The important area and also easiest is I believe the metals.  Unfortunately if food suppliers are fraudulently putting adulterants into the food (to boost profits) it is not possible to easily identify.  For most of these topics you need a mass spec and the technical ability to maintain it.    You might find some specific tests can be done with a pH meter.

The reason Philippo didn't find much about this topic so far is because much of it is out of reach of the DIY realm.  Kind of the best you can do is buy and install the best multi stage water filtration system you can at home and then shop for food wisely.  You can test for metals and related with some simple chemical colorimetric tests.  Otherwise cook everything well, don't eat meat or fish, and eat nothing raw unless it's fermented.

It is possible to do a DIY test for example, to find:

" Organic rice baby cereal, rice breakfast cereals, brown rice, white rice—new tests by Consumer Reports have found that those and other types of rice products on grocery shelves contain arsenic, many at worrisome levels..  Worrisome arsenic levels were detected in infant cereals, typically consumed between 4 and 12 months of age. "  http://www.consumerreports.org/cro/magazine/2012/11/arsenic-in-your-food/index.htm    " Roughly 10 percent of our juice samples, from five brands, had total arsenic levels that exceeded federal drinking-water standards. Most of that arsenic was inorganic arsenic, a known carcinogen.  As for lead, about one fourth of all juice samples had levels at or above the 5-ppb limit for bottled water. "  http://www.consumerreports.org/cro/magazine/2012/01/arsenic-in-your-juice/index.htm


It is unlikely you will be able to test for anything like these:

"The 2005 Indonesia food scare was a food scare in 2005 in Jakarta, Indonesia, when the government found that 60% of noodle shops in the capital had been serving noodles laced with formaldehyde, a known carcinogen. Noodles in the 2007 Vietnam food scare also had the same contaminant, and the chemical preservative had also definitely been found on tofu, noodles, and salted fish.  Other food contaminants found by Depok Health agency in elementary schools in 2006 were sodium benzoate, cyclamate and borax exceeding the permissible levels."  https://en.wikipedia.org/wiki/2005_Indonesia_food_scare

"In February 2006, an unnamed former chemist at the FDA publicly revealed that benzene may be created as part of a chemical reaction during production of soft drinks, particularly those having an orange flavor.  The United Kingdom's Food Standards Agency released results on March 31, 2006 for 150 beverages. Its results showed 43 beverages contained benzene, four of which contained levels above the World Health Organization drinking water standards (10 ppb). "  https://en.wikipedia.org/wiki/Benzene_in_soft_drinks#2008


"In February–March 2013 several European countries, including Romania, Serbia, Croatia reported nationwide contamination of milk for human consumption (and possibly of derivative products) with aflatoxins. It was also reported in March that tests revealed contamination in milk produced by two Dutch farms."  https://en.wikipedia.org/wiki/2013_European_aflatoxin_contamination

" The 2011 Taiwan food scandal was a food safety scandal in Taiwan over the use of the plasticizer - DEHP to replace palm oil in food and drinks as a clouding agent as a way to keep cost down and improve profits. The chemical agent has been linked to developmental problems with children as it affects hormones.   The food affected includes beverages, fruit juices, bread, sports drinks, tea, and jam"  https://en.wikipedia.org/wiki/2011_Taiwan_food_scandal

"The 2013 Taiwan food scandal refers to food safety incidents in the Republic of China (Taiwan) that began in October 2013. Affected products included cooking oil, health pills, alcoholic beverages, milk and rice.  Chang Chi Foodstuff Factory Co. was found to have used copper chlorophyllin, an illegal coloring agent for cooking oil, in its olive oil and have adulterated its higher-end cooking oil with cheaper cottonseed oil."  https://en.wikipedia.org/wiki/2013_Taiwan_food_scandal

" The 2014 Taiwan food scandal came to light in 2014. Adulteration of cooking oil with recycled waste oil and animal feed oil was discovered in September 2014.  .. The company was found to have blended cooking oil with recycled oil, grease and leather cleaner. "  https://en.wikipedia.org/wiki/2014_Taiwan_food_scandal

On 8/25/15 2:06 PM, Bryan Jones wrote:

you can test the food yourself. Build a thermocycler and test for the presence of the CP4 EPSP synthase gene in your food.

On 8/26/15 9:29 AM, Daniel C. wrote:

Anyone sufficiently "scientifically minded" should have already found the thousands upon thousands of studies, performed over the past 20+ years, which have failed to demonstrate any harm from consuming GMO foods.

Failing to demonstrate harm over a couple decades is different from claiming a technology is 'perfectly safe'.  

[Cathal (Phone)]

If you think there's a need, then make a test kit. You've got the know-how and you evidently believe GE food is a hazard, so why not?

The fact that no consumer-facing kits exist isn't a matter of difficulty, it's because virtually everyone *capable* of making such a kit also feels it's unnecessary because they've acquired lots of domain knowledge.

You're not wrong to assert that there is a nonzero risk. There's a nonzero risk I'll be hit by a car even if I never leave my house. The question is whether a risk is worth considering.

People are generally poor at gauging risks in this way: terrorists kill fewer than falling televisions and yet.. war on terror. GEOs have literally killed nobody, while Organic/Biodynamic methods often pose real and quantifiable food safety risks (manure, humanure, failure to medicate sick animals...), yet most people are more wary of GE foods.

If you think a GE test would help people track what they eat, do it! While you're at it please include complementary E.coli and Cryptosporidium testing, which might actually save some lives.

Oh, and you've got your GE-free label, it's called Organic. Keep your mitts off the rest of our food, kthx.

[Jonathan Cline]

Cathal, It's nice that you ignore 95% of the content of a post and then slip in your bias.   Stop arguing and collaborate for a change.

## Jonathan Cline
## jcl...@ieee.org
## Mobile: +1-805-617-0223
########################

On 8/26/15 11:27 AM, Cathal (Phone) wrote:

(trolling argument)  Keep your mitts off the rest of our food, kthx.

 

[Cathal Garvey]

Asking for people to stop unnecessarily hiking the work undertaken by
farmers who feed me isn't bias, it's common sense. For people who are
willing to pay a premium for oversight and traceability, there are
already plenty of options. Calling for labels is calling for the rest of
us to pay that premium without our choice or consent.

I'm the EU. I already deal with prohibitionism thanks to scaremongering,
and I am forbidden from choosing what to eat based on my own
environmental conscience. You can be sure that if I had the choice, I'd
choose GE foods, but thanks to very well-paid lobbyists I can't.

I call 'live and let live' collaboration, what do you think?

> --
> -- You received this message because you are subscribed to the Google
> Groups DIYbio group. To post to this group, send email to
> diy...@googlegroups.com. To unsubscribe from this group, send email to
> diybio+un...@googlegroups.com. For more options, visit this group
> at https://groups.google.com/d/forum/diybio?hl=en
> Learn more at www.diybio.org
> ---
> You received this message because you are subscribed to the Google
> Groups "DIYbio" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to diybio+un...@googlegroups.com

> <mailto:diybio+un...@googlegroups.com>.

> To post to this group, send email to diy...@googlegroups.com

> <mailto:diy...@googlegroups.com>.

> Visit this group at http://groups.google.com/group/diybio.
> To view this discussion on the web visit

> https://groups.google.com/d/msgid/diybio/55DE12D5.70009%40ieee.org
> <https://groups.google.com/d/msgid/diybio/55DE12D5.70009%40ieee.org?utm_medium=email&utm_source=footer>.

> For more options, visit https://groups.google.com/d/optout.

--

Scientific Director, IndieBio EU Programme
Now running in Cork, Ireland May->July
Learn more at indie.bio and follow along!
Twitter: @onetruecathal
Phone: +353876363185
miniLock: JjmYYngs7akLZUjkvFkuYdsZ3PyPHSZRBKNm6qTYKZfAM
peerio.com: cathalgarvey

[Virari Ueb]

Cathal I would argue that there might be other reasons for  the lack of avalable   consumer GMO testing kits. If it would be that simple, somebody would sell it, it is a good bussiness even if you personally dont take GMO as issue. The problem with GMO testing is that the major GE crops are used in highly processed form such as starch, oil or   sugar in composite foods. No significant amounts  of DNA or  proteins are present.  Even well equipped labs have difficulties to detect and quantify presence of GE variety in such complex mixture. So you would need to analyze the supply chain which is out of reach of most consumers. Also you would need multiplex test to detect the increasing number of GM traits, sampling will actually destroy the food you want to eat etc. I think that the simplest way would be to buy organic or NON GMO verified for those who are so inclined and happen to  live  in US or Canada or to trust mandatory labels in counties, where labeling is mandatory. 

[Margret Storm]

I'm rather curious as to how one would go about testing for whether or not random genes were manually tweaked (and not naturally mutated/introduced through bacterial/viral horizontal gene transfer) in the first place. Besides, you realize all human-grown crops have been manipulated from the natural state through centuries of inbreeding, yes? If anything, new GMO methods are less damaging to the genome.

[Xabier Vázquez Campos]

And don't forget that aside of the traditional crop selection, and way before transgenics, crops have been genetically modified by radiation-induced mutagenesis since early XX century

[Winnie Poncelet]

Margret raises a valid point. Where do you draw the line? 

I've worked on markers to determine both parent plants in red clover, to optimize the breeding process. No direct genetic modification involved, but months and years of labwork and an indirect genetic impact on resulting populations from the breeding programme. If you were to follow every bee around and determine the father plant (source of pollen) of each seed in a motherplant that way, you have the same effect. Genetic markers make it less laborious. 

It would be a more mature question to ask what effect any sort of breeding has on genetic diversity and the role genetic diversity plays, although these questions have already been the subject of investigation.

[Cory Tobin]

> I'm rather curious as to how one would go about testing for whether or not
> random genes were manually tweaked (and not naturally mutated/introduced
> through bacterial/viral horizontal gene transfer) in the first place.

Any transgenic sequences can be detected by PCR or, even better
RT-PCR. You would purify DNA from the plant, design primers for the
specific sequences you are looking for, do the PCR and then run it out
on an agarose gel.

Most approved traits will have the CaMV 35S promoter sequence so you
can use primers for that promoter. Although, it's not guaranteed to
be in every transgenic line. If you have a have a particular trait
you are looking for, use this website to find it. It will have links
to detection information that includes details of the transgenic
sequences and suggested primer sequences.
http://www.isaaa.org/gmapprovaldatabase/

For example, if you're looking to detect Hercules RW maize
(Glufosinate tolerance and root worm resistance), the search function
will bring you to this page:
http://www.isaaa.org/gmapprovaldatabase/event/default.asp?EventID=112
which details this particular trait. Click on "Documents and Links",
then on "GMO Detection Method Database". That will take you to a page
with sequences, primers, recommended detection methods, etc. The
recommended detection methods tend to be primers and Taqman RT-PCR
probes.

-cory

[Cathal (Phone)]

I think the question was "For any given gene how would you detect modification of that gene". More of an informatics exercise than a molecular one: I imagine hidden markov modelling of the surrounding genome would help identify areas that are "too simple" because of our present difficulty and disinclination towards matching deep genomic patterns.

That's assuming you don't just glance at it and say "that's awfully prokaryotic for a plant!". :)

[Cory Tobin]

> I think the question was "For any given gene how would you detect
> modification of that gene". More of an informatics exercise than a molecular
> one: I imagine hidden markov modelling of the surrounding genome would help
> identify areas that are "too simple" because of our present difficulty and
> disinclination towards matching deep genomic patterns.
>
> That's assuming you don't just glance at it and say "that's awfully
> prokaryotic for a plant!". :)

Oooh, I see. Yeah, I misinterpreted that question.

The good thing is that today, at least, all of the traits on the
market are large transgene insertions that look very different from
the plants' innate sequences. Prokaryotic and viral sequences spliced
to eukaryotic sequences surrounded by restriction sites. Plus, the
variety of sequences used in practice is quite limited: a handful of
promoters, herbicide tolerance genes and pest resistance genes. So
the number of things to look for is quite small.

In theory, though, someone could make single nucleotide changes that
would be completely indistinguishable from naturally occurring or
random X-ray or EMS induced mutations. In that case, like Cathal
says, there's not much you could do except build a statistical model
of what "natural" sequences look like and compare your observed
mutations against the model.

Ultimately, though, I think it will be more useful (but more
difficult) to judge plants on the functionality of their mutations
rather than how those mutations arrived. IMO, good traits are good
traits regardless of whether it came from a lab or cross-breeding or
HGT. Same for bad traits.

-cory

[Nathan McCorkle]

On Thu, Aug 27, 2015 at 11:47 PM, Cathal (Phone)
<cathal...@cathalgarvey.me> wrote:
> I think the question was "For any given gene how would you detect
> modification of that gene". More of an informatics exercise than a molecular
> one: I imagine hidden markov modelling of the surrounding genome would help
> identify areas that are "too simple" because of our present difficulty and
> disinclination towards matching deep genomic patterns.
>

Yeah I was thinking along these lines... the answer to the question
"is this stuff (contaminated with) GMO" seems lie in some sort of
statistics or mathematical analysis.

That said, Cory's answer is perfect for a question like "aside from
statistical analysis, what is a good way to start checking for common
agro-industry-standard GMO". Rightfully as he pointed out, this is a
very crude test, as sequence construction can change at any point when
industry developments alternatives.

At that point, if you're really concerned about presence of GMO, you
might have much much bigger problems. If you want to /just/ detect Bt
corn, you can search for CaMV promoters, if that comes up empty you
can search for Bt protein sequence fragments, if that doesn't turn up
results maybe you want to check a Western Blot or ELISA for
functional/binding domains of Bt protein, if that doesn't turn up
results well who knows... maybe the engineers altered the structure
vastly and that turns up nothing. Or maybe this is really a GMO-free
sample.

So at that point the logic and procedure becomes quite circular in
terms of GMO, detection, form, function, role, etc...

If you screen only for common standards, you may find all standard
GMOs, but you will not catch non-standard (or newer standards that you
are not updated to, because they are trade-secrets, etc...). The only
reasonable thing to do at that point seems to be statistical analysis,
unless you have a BIG engineering budget and some serious reason to
get into blotting and enzyme function assays.

[Nathan McCorkle]

On Fri, Aug 28, 2015 at 12:26 AM, Cory Tobin <cory....@gmail.com> wrote:
> Ultimately, though, I think it will be more useful (but more
> difficult) to judge plants on the functionality of their mutations
> rather than how those mutations arrived. IMO, good traits are good
> traits regardless of whether it came from a lab or cross-breeding or
> HGT. Same for bad traits.
>
> -cory

Thinking about it now, I think this is really a MUCH harder test,
which is why no one wants to talk about it. They all want to assume
change is bad, because there's no way to really validate except
through randomized real-world trials... which takes time, is plagued
by incomplete and bad/incorrect/biased reporting... etc.

If you think about it from a system validation standpoint, what would
you do? For every type of human proteome, for every type of GMO in
production, allow two human clones to live a full life with and
without consuming/being-exposed-to GMOs and evaluate their health and
genetics and epigenetics at many stages throughout life and at death
(comment: or maybe the exposure should be devoted to another clone or
two).

Ok, great, we wrote our test, that should clear things up. Oh, but
actually, we should expand on just iterating through each GMO and
include all non-GMO as well. (and I bet there are a lot more types of
non-GMO food to test)

So applying the best test with the best heuristics really depends on
what you want to capture. Worrying about whether something is good or
bad for you is certainly more interesting than is something is GMO or
not.... especially when there are so many /simple chemicals/ that can
be deadly/horrible contaminants.

[Branko]

Philippo, you might want to check this MOOC course ,scheduled for October :
https://www.futurelearn.com/courses/food-fraud

thanx to all posting in this thread , and pity GMO  took over .

Hopefully DIY & afforable non-labeling tech  like Raman spectrometer is close  :
https://hackaday.io/project/1279-ramanpi-raman-spectrometer
http://www.sciencemadness.org/talk/viewthread.php?tid=23422

[Cathal (Phone)]

Very excited to see personal spectroscopy take off. Would be fantastic for nutritional characterisation and accountability in food processing.

[Gordana Ostojic]

I assume that Raman would be great if one is testing a bulk substitution like if milk is replaced with palm oil. What technique is good for traces? Like traces of heavy metals or small carcinogenic compounds in food?  

I didn't look closely but that DIY Raman looks like an overkill. Raman would be a fairly easy to make with nonmoving parts. You need a lens, grating, filter and CCD (ok if you don't have a ccd and have a single detector, then you need a motor)  and laser of course. I would buy from ebay.  

[Virari Ueb]

It still doesnt solve the problem that most foods only contain highly purified raw matearial and it might be very difficult to isolate and reliably quantify bacterial ESPS gene in food containing some fraction of soybean oil. Detection of GM in finalised food is rather difficult. On the other hand it is not easy for the GM companies to change the gene sequence at their will. It would be regarded as a completely new trait and the whole  new approval process which might cost something around USD 100M and last at least several years in US up to indefinetly in EU. 

 

[Mike Horwath]

Mass spectrometry (usually ICP-MS) is the standard for detecting heavy metals, and can find extremely trace amounts.  A tandem chromatography + mass spec setup is good for detecting small organic compounds like carcinogens.  Unfortunately, this stuff is expensive.  Less sensitive methods like flame spectroscopy for metals and column chromatography + IR spectroscopy for organics may be more doable in a DIY setting.

Mike

[Gordana Ostojic]

I like the last one should be doable but I know that for IR after LC, water could be a problem. Any other  IR spectroscopy type that is suitable after LC?  Raman is a problem for low sample density so I don't think that would work. On a separate note, the equipment used in academia and big name industry is a bit of an overkill. I mean if you would test milk only, for example,  and you know what a liquid chromatography spectra should look like, you don't need MS afterwards to prove what corresponds to which peak. 

Gordana

[Mike Horwath]

Yeah...the organic component needs to be separated from the aqueous solution in order to analyze by IR, probably distillation.  UV spectroscopy works fine for aqueous phase but doesn't give ability to distinguish similar compounds.  There may be some other useful techniques I am missing!

--
-- You received this message because you are subscribed to the Google Groups DIYbio group. To post to this group, send email to diy...@googlegroups.com. To unsubscribe from this group, send email to diybio+un...@googlegroups.com. For more options, visit this group at https://groups.google.com/d/forum/diybio?hl=en
Learn more at www.diybio.org
---

You received this message because you are subscribed to a topic in the Google Groups "DIYbio" group.
To unsubscribe from this topic, visit https://groups.google.com/d/topic/diybio/Vd685lcRCS4/unsubscribe.
To unsubscribe from this group and all its topics, send an email to diybio+un...@googlegroups.com.

To post to this group, send email to diy...@googlegroups.com.

Visit this group at http://groups.google.com/group/diybio.

To view this discussion on the web visit https://groups.google.com/d/msgid/diybio/1c95023f-b860-4bb4-891c-14a40cd6cb85%40googlegroups.com.