FFA deterioation

FFA is the most important criteria in almost all trading contracts and always a subject of contention.

This is due to the inherent hydrolysis reaction of water on oil, converting oil to water.

FFA hydrolysis rate depend on a number of factor, such as temperature, moisture content and shipment period

Of course - sometimes people cheat.

Generally based on experience, a good crude, even cpo with heating, are relatively stable in FFA. I have ever kept 3000mt Crude Soyabean Oil for 2 years and 1000mt Crude Groundnut Oil for 1 year with no significant increase in FFA. (why i keep so long, must asked the pseudo-Japanese trader)

But I also received a shipment of Crude Soyabean Oil with FFA increase 0.1% per week. When the courier sample from loadport arrived 1 week after loading, the FFA has differ from loadport results by 0.1%. At first we thought the shipper cheated, but one week later the same sample was tested FFA increase by another 0.1%. Further analysis by Dr. Verwey lab indicate the presence of certain bacteria that catalyze the FFA deterioration. Finally vessel arrive 40 days later and FFA increase by almost 0.5%

Crude Rice-Bran Oil, if not properly treated, could have FFA increase by 1% per day. I ever received an "Rice-Bran Acid Oil" of FFA 35% - too low for Acid Oil. Later found it is Crude Rice Bran Oil that has to be downgraded

The same enzymatic action on Crude Palm Oil resulted high FFA during wet season. The fruits need to be sent to the factory as soon as possible and first step is sterilization - using steam to soften the fruits and at the same time kill the enzyme. During rainy season when there is a delay in transport of fruits to the mill, FFA increases

As a summary - A good crude (with lower FFA/Moisture) will have a better stability than a poor crude. If one is loading CPO shipment from Malaysia FFA <4%, MNI < 0.25%, you shud be at east even the destination is Europe 40 days away.
Similarly A crude Soya oil from USA of FFA <0.75

Refined Oil is however, generally unstable, despite the enzyme is killed & FFA is <0.1% and MNI <0.1%. The FFA deterioration is fastest in heating oil like stearin than non-heated oil like olein. No scientific study but speculation is

a) Hydrolysis is a naturally occurring process. Chemical reaction rate generally fasten by raise of temperature
b) naturally occurring compound in crude actually protect the oil - e.g. the crude that i have been keeping for 1-2 yrs).Refining removed all these goodies
c) during Fractionation, the unsaponifiable matter is concentrated in the Stearin. Presumably, these are the "rubbish" that hasten the hydrolysis reaction

There is even an on-board study on FFA rate of increase from Msia to Korea - I remember the rate is about 0.01% for a 7-days journey. So for the rule of thumb if you want to be safe for the Chinese Market (the official surveyor is a communist bureaucrat), the safe level to ship is 0.07% + 0.01% of increase + 0.01% of testing uncertainty = 0.09% at disport

Of course time has change some Chinese port is very liberal but in those day when CCIB issue certificate of FFA 0.11%, you have to sell at a discount to local market because the oil is "olein" and not "refined olein"