How long can you store Consentrate at 35-40 degrees?

[Snow Hill Farm]

I just ran my RO for the first time, too late to boil tonight. Will it be o.k. to store it in my head tank until tomorrow night or the next night? The forecast is for temps in the high 30's and low 40's and no sun for the next couple of days and the head tank is under cover. Lost track of time watching the RO do it's thing and still have to clean up the sugarhouse!

[gearpump]

Yikes! I guess it depends on how high you concentrated the sap, but I would definitely not leave it for more than one night. The grade of syrup you get will probably change even with that length of time and higher concentrate may spoil completely. Unless you have some sort of refrigeration unit to store the concentrate in, you need to get it boiled as quickly as possible. Concentrated sap spoils much more easily and quickly than it would at 2%.

Anne (Marty's too busy checking on the releaser and I thought you needed responding to)

[tuckermtn]

I would agree with Anne- overnight tonight would be okay, but beyond that you will loose sugar. What % did you get your concentrate to?

[Snow Hill Farm]

Only 8%, it's been hanging right in the high 30's here so I figured the temp. would help. I'll be boiling it tomorrow morning so we will see what kind of grade I get. Good thing is I get more requests for dark dyrup than light by far...

[sapman]

I noticed even with recirculating sap for several hours before boiling, that I lose some grade from when I single passed it. So setting for a day or two would be very bad, I would think.

[maple flats]

I sold some sap to a producer with an RO when I couldn't keep up. When he was getting ready for Maple Weekend he concentrated to 8% on Thursday, put it in a refrigerated tank he has (set to 30 degrees) and boiled it on Saturday. What he gathered Friday and saturday was concentrated on Sunday early and he boiled it Sunday. After these holds he still made a rather light shade of med. A, on 2 day old concentrate. An argument might be made that he could have made light if boiled sooner, but I'd make medium all season and have no complaints.

[Bucket Head]

I bought an RO unit before the season started and figured I would experiment this year with storing ROed sap so I knew what I could and could'nt do for future seasons. I did'nt know what to expect but I was pleasantly surprised.

For most of the season I ROed sap late in the evening after collecting and then boiled it the following day. Sometimes I got to it early the next day and sometimes it sat until late afternoon, so the exact hours it was stored varied day to day. There was one occasion where I let the concentrate sit for two days. I kept the concentrate in insulated dairy bulk tanks. I kept the sap as cool as I could with big ice cubes- I took a bunch of 5 gal. bulk jugs and partialy filled them with water and froze them in a chest freezer. I would put some in the tank and would rotate them out with ones right out of the freezer. Most of these "tests" were on about 175gal. batches of concentrate. The batch that sat for two days was just a little under 200gal.

Using the ice cubes, I was able to keep the sap at 41 degrees or lower all season. The two day-200gal batch got up to 44 degrees. That was at the end of the season when outside air temps. were a little higher, and I gambled a little by not putting extra ice in it. Like I said I was experimenting so I figured that would be a good test.

I made medium with all of the concentrate except the 44 degree batch. That came out dark. I thought for sure that it was going to be grade b, or worse, but it was fine.

Like it was stated above, I'm sure I could have made lighter syrup if I boiled immediately. I don't have a lot of customers that ask for lighter syrup so I was'nt worried about having more dark product, and a quart of light sells for the same price as a quart of dark.

Now for everyone reading this and trying to determine if it will work for them, there are a lot of variables to think about. This season was pretty good temperature wise. No really high temps. or prolonged heat waves. It was cool for the most part. Maybe next season will be different. Maybe my results won't be repeated during a warmer season? Do you have insulated storage tanks? If not, this trick is'nt going to work for you. Where are you going to have your tank(s)? If their not shaded, this is'nt going to work as well. Mine are shaded for about 90% of the day. They are only in the sun early in the morning when its still pretty cold out. Its surprising how much the sun heats up a container of sap, even when the outside air temp. is very cold. Also, clean tanks are a must. I rinse my gathering tank out after every use and I scrub and rinse each bulk tank out after I empty it. This goes a long way in syrup quality wether you RO or not.

If you can meet these "requirements", you could probably hold concentrate for a little while and be allright. Sometimes circumstances don't allow daily boiling, but if you can keep what you have cool you can still make decent syrup. Good luck to everyone who is going to try my experiment next season. Be sure to let us know how you did.

Steve