Several words about our Maple operation. Like the other aspects of our farm we try to proceed in a way that is more artisanal than industrial. We are not fans of Earl Butz.
That outlook, together with inherited proclivities and inclinations, conspire to guide our choices about what we do and do not do in our Maple Sugaring operation.
Although we use plastic tubing for about 3/4 of our taps, they are on gravity. We do not use vacuum. All the research shows that vacuum has no ill effects in the orchard but in my experience, it is a pain in the neck. One more electrically or gasoline driven system to break down at, of course, the least convenient time. Not using vacuum means that we do not get runs on marginal days, so our overall production is reduced.
We do not use Reverse Osmosis, commonly referred to as "RO". This process uses very fine membranes and high pressure electric pumps to concentrate sap to a higher density before it is boiled. Sap comes out of the tree at typically somewhere between 1.5 and 3.0 % sugar. Syrup is 66% sugar. That's a lot of boiling to send all that water out through the cupola as steam. If you double your density with an RO, you halve your boiling time, so you can see the attraction. All the research shows no degradation of flavor or quality in syrup that has been made from concentrated sap. RO's are a mechanical system subject to the same untimely breakdowns as vacuum setups.
We bottle in glass. While we do use plastic tubing to collect sap, the amount of time the sap spends in contact with the plastic is pretty minimal compared with a jug of syrup sitting on a shelf. I like to be able to see what we are selling and assume folks appreciate seeing what they are buying. All the research shows no degradation of flavor or quality of syrup stored in plastic.
The last modern technique that this iconoclastic curmudgeon eschews is using a Filter Press. Another electrically driven pumping machine, the process requires adding a significant quantity of diatomaceous earth (food grade, of course) to the syrup in order to make the process work. (Check it out: https://www.youtube.com/watch?v=S77te5xuja0). This produces an impeccably clear product. We filter through a paper cone filter when we draw "almost syrup" off the rig, then filter again after we have "finished" to exactly syrup just before we bottle. It comes out clear enough for me and does not involve a mining operation of a limited resource in the Southwest or cross country material transit. All the research shows no degradation of flavor or quality of syrup filtered through a filter press.
On a final note of obstreperousness, we bottle in English measure: Quarts, Pints, Half-Pints. I have nothing against the metric system. English measure is just what I grew up with and what is familiar to me. Besides, it is in no small part the influence of our metric measuring Canadian friends who are helping to drive the (to me) regrettable industrialization of Maple Sugaring. So there.