<table border=0 cellpadding=2 cellspacing="0"><tr><td>
<pre>Dear all

It's interesting to read you're discussions on chemical parameter
measurement.

Our company, DiaMed has developed a test system for measuring:

FFA
Aldehyde
Peroxide

In food stuffs, including olive oil.

The system is faster, cheaper and is more ecologically friendly than
standard methods.

If you want to know more, contact me at

d.bashforth@diamed.ch <mailto:d.bashforth@diamed.ch>

Best

David Bashforth

-----Original Message-----
From: Hanna Meier [SMTP:hannameier@socialinsight.ch]
Sent: Donnerstag, 26. Oktober 2000 09:23
To: OliveOil@egroups.com
Subject: [OliveOil] re: Definitions

Hello Peter Caird

What means "Rancimat reading"? I have never heard of this process.
Can you
do it by yourself or is it done by a chemist?

Regards,
Hanna

PS: What ist FFA, does it mean acidity?



-------------------------- eGroups Sponsor


------------------------------------------------------------------------
You have an olive or olive oil recipe you want to share with others,
visit our sister group:
http://www.egroups.com/group/OliveOilRecipes

------------------------------------------------------------------------
This link is the key to an exciting bonus for you! Read below.

https://trading.etrade.com/cgi-bin/gx.cgi/applogic+lpmasterpage?SCS=ONCR759&
RID=1830155029

JOIN E*TRADE AND EARN A $75 SIGN-UP BONUS FOR YOURSELF, ALONG WITH
$50 FOR OLIVEOIL!

------------------------------------------------------------------------

Five steps to help promote OliveOil:

1- Add a general link to the group on your website:
http://www.egroups.com/group/OliveOil
2- Mention the group and its URL in your newsletters and
publications.
3- Invite others to visit:
http://www.egroups.com/group/OliveOil
4- Add a subscription link on your website. See how here:
http://www.egroups.com/promote/OliveOil
5- If you would like me to send a formal invitation to people you
know, write to me at OliveOil-owner@egroups.com
</pre>
</td></tr></table>

<table border=0 cellpadding=2 cellspacing="0"><tr><td>
<pre>Hanna

FFA - Free fatty acids. Have a look at my home page for a chemical analysis
of oil.

Rancimat testing. A test to see how long it takes before oil goes rancid.
Involves heating the oil to 120C and determining rancidity by measurement of
chemical change. A chemist's job altho a good nose and palate can determine
same.

Regards
Peter Caird
www.victorianolivegroves.com
</pre>
</td></tr></table>

<table border=0 cellpadding=2 cellspacing="0"><tr><td>
<pre>Rancimat test - used to test the keeping qualities of an edible oil eg
Palm oil, olive oil, peanut oil etc. A high temperature is used which
can be extrapolated to room temperature. Oils with low rancimat levels
(measured in hours) are less stable than oils with a high rancimat
level. Essentially the test is an accellerated stability test.

The stability of the oil depends on the fatty acid composition of the
triglycerides and the amount of antioxidants present - polyphenols and
tocopherols.

The equipment is expensive eg $30,000. Industry uses the rancimat test
because it is quick and easy.

Regarding Free fatty acid - this is present in very low quantities in
olive fruit and olive oil made from high quality fruit. Normally in the
synthesis of triglyceride (the 985 oily fraction of olive oil) the
following reactions take place.

Carbon Dioxide + Water + sunlight -----> sugars (eg glucose)

Sugars break down to many smaller molecules including those required to
make trigliceride.

The net effect is

Sugars ---------> Glycerol and Fatty acids + many other molecules

Glycerol + fatty acids ----------> Triglyceride (here the fatty acid is
bound)

With fruit that is of poor quality through harvesting damage and
prolonged storage or disease the reaction goes:

Triglyceride ------------> fatty acid (here the fatty acid is free) +
glycerol - fatty acid derivatives so the levels of free fatty acid
starts to increase

The free fatty acid will also increase in olive oil throgh hydrolysis
reactions.

Triglyceride + Water -----------> Free fatty acid + Glycerol fatty acid
derivatives

A high free fatty acid in olive oil gives off flavours and is ass
ociated with other off flavours due to oxidation reactions.

I measure the free fatty acid recently in varietal oils from excellent
fruit. the levels were less tha 0.3%. Some international studies gave
ranges from 0.3-1% (the upper limit of extra virgin olive oil). Olive
fly can increase the free fatty acid in olive oil to 6%.

To give you a feel for chemical tests that are an indication of quality
- for Koroneiki olive oil (Koutsofakis and others)

Acidity - 0.5 to 0.6%
Peroxide 6 t0 8 meqO2/kg of oil
UV - K values - wavelength 232 - about 1.5 wavelength 278 about 0.1 to
0.14
Rancimat = about 10 to 11 hours

Stan kailis
</pre>
</td></tr></table>

<table border=0 cellpadding=2 cellspacing="0"><tr><td>
<pre>Regarding FA levels

High palmitic acid levels would promote an incease in LDL-cholesterol
but the net effect would also relate to the oleic acid% and the
antioxidants - polyphenols and tocopherols.

The higher the polyunsaturation - ie linoleic and linolenic acids the
less stable the oil and so prone to oxidation and formation of off
flavours.

The ratio of linoleic to linolenic is believed to be important regarding
the value of omega 3 and omega 6 fatty acids.

I know the answer is fuzzy, but is this the type of info being
requested.


Stan Kailis
</pre>
</td></tr></table>

<table border=0 cellpadding=2 cellspacing="0"><tr><td>
<pre>Stan- You seem to be the chemistry expert. I was reading that Tunisian olive
oil has a different chemistry (MUFAs vs. PUFAs???) than that found in the
Mediterranean oils. Can you comment further and shed some light on which one
is healthier?
Thanks,
Wendy
----- Original Message -----
From: Stan Kailis <kailis@ca.com.au>
To: <OliveOil@egroups.com>
Sent: Monday, October 30, 2000 5:18 PM
Subject: Re: [OliveOil] Fw: Definitions


> Regarding FA levels
>
> High palmitic acid levels would promote an incease in LDL-cholesterol
> but the net effect would also relate to the oleic acid% and the
> antioxidants - polyphenols and tocopherols.
>
> The higher the polyunsaturation - ie linoleic and linolenic acids the
> less stable the oil and so prone to oxidation and formation of off
> flavours.
>
> The ratio of linoleic to linolenic is believed to be important regarding
> the value of omega 3 and omega 6 fatty acids.
>
> I know the answer is fuzzy, but is this the type of info being
> requested.
>
>
> Stan Kailis
>
>
>
> ************************************************** ***
> Addresses:
> Post message: OliveOil@egroups.com
> Subscribe: OliveOil-subscribe@egroups.com
> Unsubscribe: OliveOil-unsubscribe@egroups.com
> List owner: OliveOil-owner@egroups.com
> URL to this page: http://www.egroups.com/group/OliveOil
>
>
>
</pre>
</td></tr></table>

<table border=0 cellpadding=2 cellspacing="0"><tr><td>
<pre>Dear All

MUFAs = refers to mainly to the Monounsaturated fatty acid - Oleic acid
PUFAs = referes to Polyunsaturated fatty acids - Linoleic (n-6) and
alpha-Linolenic (n-3) acids

The levels of these acids (actually bound to glycerol as triglycerides)
varies during the different maturation stages of the olive, varies with
the variety and the growing conditions.

It is generally accepted that cooler areas (eg Tuscany) will give an oil
with higher oleic acid than warmer climates. Most of the research
however has be reported as individual studies so that comparisons are
like apples and oranges. However there is a major trial underway in all
the major Mediterranean Producing countries with some 10 or so
varieties. This study will give more definitive information.

Regarding the PUFAs there is a wide range acceptable for EVO, however
the Linolenic has to be less than 0.9% (IOOC). There is no problem if
the levels are higher eg 1.5% regarding the olive oils nutritional
value. But the IOOC Linolenic acid level is used to establish the
authenticity of the olive oil. Seed oils like Canola have higher levels
of Linolenic acid.

Also the higher the level of unsaturation ie mor PUFAs leads to a less
stable oil, however this has to be counterbalanced by the levels of
antioxidants that protect the oil (these will also vary by similar
factors to the fatty acid profile as well as stress eg drought.

A higher Linolenic than the IOOC may actually be of benefit
nutritionally for reasons other than those associated with oleic acid.

If more inf is required let me know.

Stan
</pre>
</td></tr></table>