I went to a good friend's funeral(Philip Grandio age 80) that I had known and worked with as a Chemical Engineer for 30 years who is from Tampa but has lived in Texas since the 50s.

Well, my friend was a Chemical Engineering graduate student at U of Florida in the 1950s and part of the team who was doing early research into the process for making OJ concentrate using propane to form propane hydrates.

I suppose someone may have invented and tried such a method for concentrating orange juice. But that method has never been of any significant commercial importance (I've never heard of it). As far as I know, all commercial FCOJ in the world is and has always been made using Florida technology -- juice is flash pasteurized, then evaporated in stages in a TASTE evaporator, in which the warm juice is sprayed down through a series of towers under a partial vacuum. Volatile essences are recovered from the vapor stage and added back, along with some fresh juice, to make a uniform product. Here are some links on the history and methods used.


http://www.practicallyedible.com/edible.nsf/pages/frozenorangejuiceconcentrate

http://www.ultimatecitrus.com/pdf/fcoj.pdf

http://www.jbtfoodtech.com/Solutions/Equipment/~/media/JBT%20FoodTech/Images/Modules/TASTE%20Evaporator/PDF/408%20GB_LRRGB.ashx

I enjoyed looking at the last site as it helped me to picture the process of FCOJ.


Back in the '80's I worked for Eastman Kodak (no they didn't do just film) in one of their maintenance shops. One day a large centrifuge was brought in. I can't remember if Eastman has purchased it or if we were repairing it for some company. It was 316 stainless steel in it's entirety. Anyway, the mechanics began dis-assembling it. All too soon, it became apparent that it had come from an orange juice processing plant. Raw fermented orange juice spilled out onto the floor and the men all ran outside to get away from the odor!!

Inside the cavity was a wall with pencil sized holes evenly spaced all over it. Further inside it was vanes that spiraled around and down the length of it. From my experience, I now know that was probably an extractor. The centrifugal force extracted the juice and oil from the rinds and then the juice concentrate was fed out through the holes in the wall separating it from the pulp. The pulp was then funneled down the centrifuge on to a collection bin.

Thanks for sharing that Malcom!