Minimum Brix in relation to spoilage potential

[woodguyrob]

As a beginning hobbyist NOT selling syrup, i'm more concerned with a batch that may spoil vs. crystalize.

So as I learn how to better use the hydrometer, and assuming syrup is heated to minimum 180*, clean jars filled close to top, seal and lay them on their side, what percentage under 66.8 brix will likely allow mold growth/spoilage occur?

For example if syrup is 66.8 brix at 60* f will 2 points/percent under @ 64.8 brix be a red flag for spoilage? Is there a rule of thumb or an established minimum brix that will lead to spoilage?

[jdircksen]

I'm not quite following your question. While you are boiling, check the brix with your hydrometer. At 211*F finished syrup is 59 brix. At that point, you have syrup so bottle it right away while it is above 180* and you're all set. I have a 2 year old bottle that I haven't opened and it still looks fine.

You do not need to let your syrup cool to 60*F in order to check it.

[maple flats]

I have bottles that are 10 yrs old, they still look fine, but I always bottle at 185-187 and have the density at 66.9%. I use a Murphy cup which corrects for any temperature without using any charts or guessing.

[tgormley358]

I think the poster wants to know if he bottles at lower density than 66.9, how much lower can you go before creating spoilage? Is that right Woody? But why would you want to do that?

[woodguyrob]

What I'm curious about is at what brix does mold/spoilage come into play. Regardless of whether or not checked at hot or cold temp.

[woodguyrob]

I'm not quite following your question. While you are boiling, check the brix with your hydrometer. At 211*F finished syrup is 59 brix. At that point, you have syrup so bottle it right away while it is above 180* and you're all set. I have a 2 year old bottle that I haven't opened and it still looks fine.

You do not need to let your syrup cool to 60*F in order to check it.
Thx jdricksen. I understand 59 brix at 211* is finished syrup. So using this example @ 211* how many brix under 59 will lead to mold growth. Just curious is there is a couple of brix/% leeway or is it that precise.

[tgormley358]

I don’t know the answer to that, but I would hazard a guess that risk of spoilage goes up rapidly below 66.9, so not a guarantee but why risk it. On the other hand if you’re not selling it and are willing to store it in the fridge, I think you’d be OK. If you put it on the shelf at room temps the risk probably isn’t worth it for all your effort to make the syrup. Just my opinion as a relative newbie (5years). Good luck

[johnallin]

At 64.8% sugar you don't yet have syrup - short answer would be yes it's a red flag. Close is only good in horseshoes...

[DrTimPerkins]

At syrup sugar levels (Brix > 66.5), you can have microbial growth, but it is very low because only a few types of very hardy things can survive the low water activity (0.86 Aw), which is a measure of the availability of water for growth. Therefore the probability of spoilage tends to be relatively low. As you decrease the sugar level below 66 Brix, the water activity increases, more types of things can grow in syrup, and the growth rates will be faster. Water activity at 64 Brix is around 0.88 (pure water is 1.0). Once you get below that point, more things can growth and the growth will be MUCH faster.

21134

In the lower right part of this diagram, M=mold, Y = yeast, B = bacteria. As you can see, at right around 0.88, the growth curves for all of these go up very fast.

Coincidentally, you can also see in this diagram, non-enzymatic browning (one part of the color/flavor development in syrup) INCREASES as water activity decreases (in the range of sap to syrup, 1.0 - 0.86), meaning that this component of color and flavor development also happens quickly across this range during evaporation.

Going above 67-68 Brix you get crystallization of sucrose, therefore the range of 66-68 Brix works well for syrup because it strikes a good balance between low spoilage tendency and low crystallization tendency.

So there really is no point at which we can say lower than proper syrup density is OK...just that: 1) it doesn't meet the legal definition of maple syrup and 2) the probability for spoilage increases as you reduce Brix level of syrup.

[TheNamelessPoet]

is there a relationship to spoilage in regard to temps also? like if temps are 36-38° (fridge) 10 brix or 20 or 40 brix you have say 5 days before it gets unusable?

asking for a friend 😉

[DrTimPerkins]

is there a relationship to spoilage in regard to temps also? like if temps are 36-38° (fridge) 10 brix or 20 or 40 brix you have say 5 days before it gets unusable?

Again, there is no line that can be drawn for such things...

This subject was beaten well beyond death at: http://mapletrader.com/community/showthread.php?35367-Safe-temperatures-to-store-Sap-vs-Concentrate-vs-Syrup&p=380498#post380498

[woodguyrob]

DrTimPerkins Thank you. Exactly what I was interested in learning.

[Big_Eddy]

The probability of spoilage is dependent on the Initial concentration of bacteria (I) in the sap, the total mass of sap (M), the storage temperature in absolute degrees Kelvin (K) and the length of time (L) since the sap was collected.

Use the mnemonic MILK


Sent from my iPad using Tapatalk