Dear Mr Gerry, For the details of deodoriser design you will have to speak to some one experienced in that field, on which I am not. There are three basic designs: Batch deodorisers which can be said to have one stage, semi-continuous ones which have 4-6 trays (stages) and continuous ones which are designed to provide the required number of theoretical plates, not stages. You have not said which type you are working on, but I suppose it is the semi-continuous one and here you decide the number of trays according to the throughput you want and comparative costs. Regards, FP (17.10.2011)

Dear Mr Sujan, There is no such thing as best frying oil any more than there is best car or best bicycle and I do not even know the price of oils in your country. All I can tell you is that PO and P.Olein are the ones most widely used in the world and they are also usually the cheapest, although that depends on the country. Regards, FP (13.10.2011)

Dear Mr Liew, None of the trading specifications I have seen for these oils mentions soap content. But as the normal refining processes for these oils do not involve use of alkali, no soap is formed and if you tested them I would expect the answer to be nil. Regards, FP (08.10.2011)

Dear Mr LMY, You are making many mistakes in your English and cannot understand your description very well, but I am not an analyst. I have not heard of this trouble before but you must be doing something wrong somewhere. If you re not getting a blue colour after addition of starch, then some thing is wrong with your starch or the way you are preparing it. My advice is to get a good original copy of the method and follow it to the letter. Regards, FP (04.10.2011)

Dear Mr Awasthi, There is no formula that gives the refining losses in oil processing because there is a very wide range of methods: physical, chemical, caustic soda, soda ash, weak caustic, strong caustic etc an equally wide range of plant: batch, continuous, semi continuous etc and a big variety in the quality of crude oils. The only figures I have seen is from plant manufacturers who give guarantees about the performance of their own plant in a country like Malaysia where the quality of CPO is very uniform. Regards, FP (02.10.2011)

Dear Mr LMY, I have not compared all the analytical methods in existence and I have not heard of the Spectrum method. The AOCS method is recognised every where. But I do not know how one would judge accuracy in a PV test, or why you are concerned with such trivia. The best policy is to use the same methods as your suppliers and customers so you can minimise disputes, rather than worry about meaningless accuracy. Regards, FP (02.10.2011)

Dear Mr Adi, Not only P.Olein but also PO and PSt darken during frying, but we do not know exactly what is causing it or how to prevent it. All oils suffer from this, and PO most of all. The cause is not carotene formation because it is destroyed by heat. But PO is particularly rich in tocotrienols and although these are good, natural, antioxidants, some of them seem to develop dark colours when oxidised. The problem has so far defeated MPOB, Unilever, Cargil and all the other multinationals who deal in PO, although it must be said that these organisations do not have any strong incentive to spend money on the problem. It is the frying industry that has the strongest incentive, but they are not in the habit of doing much research. Regards, FP (29.09.2011)

Dear Mr Saad, You are a student training for an honourable profession. I do not think it would be honest behaviour for me to give you the answers so you can pass them as your own. If you have weak areas in your knowledge now is the time for your professor to identify them and correct them. Regards, FP (28.09.2011)

Dear Mr Sethi, I find it incredible that you have been buying something of which you do not even know its name. I do not know either, because all you told me is that it is in white lumps and melts above 55C. It could be RBD palm stearin or stearic acid, but to be sure I would have to know its proper melting point and IV. As it is, only your supplier can help you further. Regards, FP (29.09.2011)

Dear Mr Azreen, You are asking some very good questions for which we only have partial answers. The colour always changes for the worse whenever you do anything to the oil and it is probably due to oxidation of some of its trace components which vary in different crudes. Some times the change is very small and you can hardly see it and some times it is quite large. The PS always suffers most because the pro-oxidants tend to concentrate in it. The source of the trouble is the quality of the crude oil. There is no standard method for measuring colour stability, but surely you can improvise a simple test to use in your refinery? There is also the DOBI test which correlates well with the bleachability of the crude oil and it may correlate with colour stability too. In refineries you have fantastic opportunities to do simple, practical, useful research work. Do that and do not wait for research institutes and universities to do it for you. You can waste all your life waiting like that. Regards, FP (23.09.2011)

Dear Mr Jain, Your questions are on commercial and shipping matters which have nothing to do with technology. Re minimum quantities, I would think one 20 ft container carrying about 20 tonnes in drums would be feasible. For the rest you better find a shipping agent in India with experience this trade, or an export merchant in Malaysia and have a good talk with him. Regards, FP (22.09.2011)

Dear Dr Derrick, The problem is because the material is PFAD, not because it is hydrogenated. Several years ago, it was found that straight, natural, PFAD contained some very variable amounts of dioxins. Some batches were well within legal limits, but a high proportion of them were far outside and the research institutions in Malaysia and Indonesia started working urgently on the problem to find out where the dioxins were coming from. I did not hear what happened afterwords, but since the animal feed industry kept quiet I assumed the problem had been solved. If you use copra, I suggest you look into that too. As you know, dioxins are extremely hazardous and extremely persistent and. so for animal feeds you should only use PFAD which has a certificate of analysis or similar. Regards, FP (19.09.2011)

Dear Mr Khadka, On the effects of reprocessing I have given you my expert opinion. If the law does not mention reprocessing, then it is permitted and I cannot see how any government official can stop you doing it. If the reason they give is that it produces toxic compounds, it is for them to prove it. I think your problem is legal rather than scientific and as it affects the whole of your industry you should be able to engage a good lawyer and challenge it in court. Scientific papers are not published on the internet. I can only help you further on a private consultation basis. Regards, FP (19.09.2011)

Dear Mr Khadka, When there are disagreements like yours, things are never as simple as they appear. You only wrote to me 3 or 4 lines, you have not read every word of the law in question and the devil is always in the detail. I think if your law prohibits reprocessing, the reason is not that reprocessing of pure old oil will generate any toxic compounds but that you my then start taking back old oil from the end users. Such oil would present a very big health risk as people can put anything in it before returning it to you. I regret I cannot send you any papers. Regards, FP (17.09.2011)

Dear Mr Khadka, If the reprocessing of the old oil is done like the crude oil, there would be no risk of any changes in its composition, trans formation etc. The only change you can expect is that its natural antioxidants will be depleted and its flavour stability and shelf life will be reduced. So have a policy of blending it off in similar percentages every time, to ensure uniform out going quality. Regards, FP (16.09.2011)

Dear Mr Abhishek, In a perfect world, the price fob Indonesia should be lower. But how do you know some one else in the chain will not use it as an opportunity for extra profit? The mills may raise the price of their CPO, or the refineries may increase their margins, or the traders can do the same. Also I expect Malaysia will be watching the situation and getting ready to act if required. As for the rest of your question, sorry it is inadmissible. Regards, FP (15.09.2011)

Dear Mr Sunny, The number of litres of palm olein per tonne of palm olein depends on the temperature, but at 40C will be 1110 litres. The grades available are crude or RBD, There is another similar product called superolein, with lower cloud point but a little more expensive. Regards, FP (14.09.2011)

Dear Mr Irfan, As in most industries, the bigger the scale of production the lower the operating costs will be and 10 tonnes per day seems to me near the minimum possible quantity. On the questions you asked I can only help you privately for a fee. Please contact me on my private email address if you wish to go ahead. Regards, FP (14.09.2011)

Dear Mr MY, The quantity you want is called specific volume and shipping companies want to know it because their tanks are calibrated in litres while cargoes are sold in tonnes. For CPO it is 1.120 and for PFAD it is 1.155 litres/kg at 50C. Regards, FP (07.09.2011)

Dear Mr Rao, I do not think the straight biodiesel from PO or PSt will pass the ASTM cold test, but in the West this BD is normally blended with other grades to make it acceptable. If you distil it, the cold test on the whole product will not change, but you can select a fraction which will give better figures. The problem then will be what to do with the rest of it. Regards, FP (09.09.2011)