Batch boil vs. Continuous flow

[Rick M]

Last year I decided to run about 18 taps in my yard in order to get a gallon or two of syryup and show my kids what is all about. To my pleasant surprise, both the kids and my wife thought it was great...so much so that they cannot wait to boil again this season.

We boiled on a block arch using 2 turkey fryer burners and a 30" x 30" x 18" deep flat stainless pan boiling down 25 gallon batches at a time over 8 or so hours each.

I am looking to upgrade to about 30 taps, and find a more efficient way to boil. Here are my concerns and questions:

By using a preheater on top of a flat pan (no dividers), and constantly adding sap as the pan evaporates, will I develop alot of niter and get dark syrup? Or would it be more advisable to acquire a larger flat pan (2 x4) and run small batches, concentrate it, and then combine all the concentrate and finish it once I have a couple gallons of "almost syrup". The final option I was considering was a 2 x3 or 2 x 4 divided pan and continually trickling in sap off of a preheater, and drawing off 219 degree "just about finished" syrup.

Any help or comments would be great.

[adk1]

A divided flat plan would be the best. Look around for a leader half pint evaporator or a we mason or similar. They are good for about 50 taps or better

[On the ledge]

I have 50 taps and a Leader 1/2 pint, I have to boil off at least 70 to 80 gallons of sap to be able to draw off near syrup. With 50 taps I wish I had a 2x4, with good runs I have many times had 1 or 2 days of boiling all day. The best I could seem to do was 7 gallons per hour . If you ever plan on adding more taps go with a 2x4.

[adk1]

Check out we mason. He makes a nice 2x4 evap for a reasonable price

[Rick M]

Thanks for the input. I've looked into both Mason & the 1/2 pint, and it seems like both are nice rigs. I guess my question is more along the line of what would be the advantage of a 3 section divided pan over a flat pan w/o dividers.

Furthermore, if I went with just a plain flat pan, would it be beneficial to use a preheater and trickle sap in while boiling without drawing anything off. I am worried that by doing it that way sap sits in the pan too long and makes a really dark syrup.

[adk1]

The divided pan allows for the gradient to establish.

[TonyL]

I'm new to this myself, but I can tell you that last season we batch boiled on a 2 x 3 flat pan, no dividers. We do utilize a smaller tank as a preheater, and it trickles into the main pan constantly. Our procedure was to boil 50 gallons or so, then shut down for the night. Next morning we would pour off the concentrate from the day before, give the pan a quick clean, and refill with sap and repeat the procedure. The concentrate was finished over propane in the shack while we were boiling sap. Once a rhythm was established, it went pretty smoothly, and our finished syrup was not what I consider dark. I considered trying to run 100 gallons through without draining off concentrate, but like you I worried about syrup being too dark....may experiment this season. 50 gallons at a time, batch style with preheater trickling into pan, made beautiful syrup however.

[optionguru]

Last year I batch boiled every other day when I had 40 to 60 gallons of sap and I used a homemade oil tank arch with 5 steam table pans, my syrup wasn't light amber but it's also not too dark and everyone who got some loved it. I think batch boiled darker syrup tastes great, I've been toying with doing continuous flow with my new pan and added taps but I think I'm going to batch boil again. I think it's easier to just keep adding sap and finish and filter a few gallons at a time instead of constantly watching the thermometer. It's a learning experience though and I could change my tune a week into this years season with my new pan and arch.

[Big_Eddy]

With 30 taps I feel there is no benefit to trying to run a continuous flow. TonyL nailed it above. Keep it simple, save your sap up until you have 60-80 gallons, then boil it all down and finish it off in 2x3 flat pan on a block arch. 3-4 days collecting, 10 hours boiling. Final finishing on the stove.

If you finish today what you started today, your syrup will be no darker than a continuous flow process where the whole first day of boiling goes into sweetening the arch and syrup starts to flow out day 2. The syrup will be EVERY BIT AS GOOD done that way as if you try to sweeten your pans, and you won't have 1-2 weeks "investment" tied up in the pan.

I've done both. I feel ~100 trees is the point beyond which continuous flow is better. Below that I'd batch boil.

[maple flats]

The longer it stays in the pan, the darker it gets, but dark has more flavor. While I make light, medium and dark, I sell lots more dark, by customer request. In fact at retail I sold about 240 gal dark in 2014, about 3 gal light, and about 15 gal medium. I still have all 3 grades in stock, but I'm out of half gal in medium only. I also sold about 18 gal B. Of the light and medium that I did sell, most was on internet sales, my local demand is almost all dark.

[Ausable]

Hi Rick M - You have received some excellent advice so far - That is about to change...........LOL ---Kidding. Either way is good and which You choose depends on the amount of Sap You have and the time You have to boil it. My lightest color came when I batch boiled. My first batch in my small - 2'x5' continuous flow will be medium and after I sweeten my pans (I'll assume You know what I mean) The color gets darker with following boils. Now in my part of Michigan - most folks prefer medium to dark - 'cause that is what maple syrup is supposed to look like. Now in Your area - Lighter is probably preferred by folks that know maple and darker for the city folks because they were raised on pretend maple syrup - like me. Yes - rig a preheater when you batch boil - saves some boiling time. I batch boiled till I exceeded my own 55 spiles. Some of my kids and grandkids started tapping in their area 75 to 150 more spiles and I was swimming in sap and couldn't keep up. So --So one of my Sons and one of my Grandsons built me a 2'x5' Fuel Oil Tank Arch and a 2'x5' continuous flow flat pan (no flues) with five divided sections (2 sap and 3 syrup). It is a basis continuous flow - but it keeps up. I have 6 storage barrels so I can handle approx. 300 gallons on site. With my old 30"x30" batch pan - I would start a boil with about 50 gals of sap on hand. With my little continuous flow I have to have at least 100 gallons to start a boil and prefer more. I kind of jumped around with my reply - but - as You discovered --- ask questions -- You will get answers. LOL --- You will get answers to questions You didn't even ask. -- Good Luck and Have Fun. ------Mike------

[Rick M]

Considering your input and advice, two factors have me leaning toward batch boiling again as I did last year. First, I already have a homemade 304 stainless pan I welded up a few years back to boil lobsters in. I don't want to spend upwards of $500 on a new continous flow pan if I'm not gonna see a marked difference in evap rate or quality of finished product. Although it is a little warped, I can bring my ice cold sap down from 16" deep (28+gallons) to just about 1" deep ( <1 gallon) before I kill the burners, and pour it off to be finished. Secondly, is with a flat pan there is less of a need to watch over it while it boils...especially with propane burners.

For what it's worth, I was able to get 5 GPH evap rate most days using that flat pan and block arch w/ 2 propane burners. So I am not sure how much more efficient I'd get with a 2 x 3 Mason, 1/2 Pint, or similar rig. As for propane consumption, I got 2- 28 gallon batches out of each 20lb tank. I was able to get $12 refills on my tanks at a local commercial propane distributor Although the money can add up with the propane, the idea of "set it & forget it" is kinda nice.

I think I'll spend this year's "Syrup Addiction Allowance" on some smaller items like a few candy molds, hydrometer cup (instead on my Thermos bottle), and maybe that nice little single cone filter unit that Leader makes

[Pete S]

If I appear to "high-Jack" this thread I apologize but this is a huge interest of mine.

I currently have a 2 x 3 flat pan with a 1 x 2 preheater pan. By the end of the day the preheater is boiling and we can run straight through most of the time from tank to preheat, to pan.

I heat with wood on a 250 gallon rig I built myself with an 8" flue.

This season (nothing like waiting till the 11th hour) I was considering to go bigger as the boil time seems too long for the amount of syrup we produce,..............but we're not BIG producers by any means, hobbyist at best. Moving inside in 2014 was HUGE.

A 2 x 4 Continuous Flow pan caught my eye. Not too pricey, and we don't have to lift it off to empty it. (although there has to be some lifting as it won't all come out under heat)

I will be visiting a friends shack this weekend who has a 2 x 6 continuous flow pan. He thought that although the continuous flow was a nice feature, "square footage is square footage" in reference to evaporation rate.

I had also considered building a new arch to accommodate the new 2 x 4 pan. He thought I may want to consider creating a continuous flow pan with what I already have, thus a 2 x 3 continuous flow.

We'll have about 70 taps this season, and don't plan to grow over 100,......seriously,............right? :-)

Thoughts and information, links, and the like greatly appreciated.

Thanks!

[tcross]

just my 2 cents... if you do ever plan on expanding your tap count to the point where you think continuous flow is necessary, you may want to consider trying continuous flow so you can get the hang of it? I started with 30-40 taps on a block arch, batch boiling, and once I moved to continuous flow, I realized it was more enjoyable for me! it's enjoyable to draw off syrup every (sense of accomplishment) so often rather then waiting till you're out of sap at the end of the day... I have a hard time sitting still watching a pan boil... so it could just be me!

again, just my 2 cents!

[tcross]

Pete, if you are considering or are going to build an arch for the 2x4 pan, you might as well build it 7' long and use your 2x3 as your syrup pan and your 2x4 as your warming/back pan and keep the preheater set up the same??!! connect them and you'll be boiling at a much higher rate then with just the 2x4!

[Super Sapper]

I assume that your 2 x 3 pan does not have dividers so I would look at a 2 x 2 syrup pan and build a 2 x 6 using all three of your pans and will be set to change over to a 2 x 4 flue pan in the future. I built a 2 x 6 a couple years ago that works well for me and you are more than welcome to look at it as I am only a few minutes west of you.

[Pete S]

Thanks! I just may take you up on that. Plymouth address,............actually Greenbush location, so I may be closer!

[Super Sapper]

I'm about 3 miles west of B&B Express.

[lisound]

Can you burn with wood? More btu's.

I use block arch and 3 steam trays. get about 7gph when the fire is real hot with hard wood.
And Batch is the way to go. Syrup always gets darker as you progress through the season. you can't beat the real light stuff on ice cream.

good luck