What causes a 'haze' to form on some sugar based syrups?

[PureCajunSunshine]

I read somewhere (don't remember where) that sometimes a haze will appear on the surface of some syrups and that it is harmless. Occasionally this has formed on the surface of my syrups, but eventually it disappears.

 

Does anyone know what causes this haze?

 

On my blog, someone asked me about a 'questionable' film that formed on the surface of her recently made elderberry syrup that was made with a stout concentration of 70% sugar...

 

http://purecajunsunshine.blogspot.com/2009...ed-to-know.html

 

 

Here's what I told her:

 

It is possible your sister may be seeing what I call a ‘sugar haze’. It’s harmless, but it sure does look weird, floating against the dark background of the darkness of elderberry syrup! Although I have never had it happen, it may be possible to contaminate a newly made 70% sugar solution with molds and bacteria. Molds are common culprits in spoiled medicinal syrups, which is why I favor going with a 70% sugar solution over the standard 65% called for in most recipes to make shelf stable syrups.

 

By shelf stable, I mean it needs no refrigeration ever. Not before or after opening.

 

A couple of times over the years, I mis-measured my sugar/liquid ratio and ended up with a batch of spoiled syrup. The mold started out looking exactly like the typical sugar haze but it continued to progress until it eventually bloomed into full spoilage.

 

Because sugar is the only preserving agent in some old fashioned syrups, and because my elderberry syrup does not contain a myriad of chemical preserving agents found in commercial products, I prefer to bottle it in pint jars and halfpint jars. That way it gets used up in a reasonable amount of time, and so the risk of contamination is reduced.

 

If your syrup was freshly made under sanitary conditions, and the measurements were correct (or pretty close to it), chances are very, very good that the ‘questionable film’ is a sugar haze. If it has been sitting around for more than a couple of weeks before developing a film or haze, and bottling procedures were less than stellar, it *might* be contaminated with growing mold spores. If this is the case, one way to find out for sure: leave it alone for a few more days, and see if it develops further into sure enough mold.

[Cricket]

Hard water?

[Violet]

Sharon,

Something, even a sugary syrup, with no processing, will mold. Remember jellies with a paraffin wax coating on top ? They molded all the time. Even though they are full of sugar. There is no vacuum seal, no heat treatment to kill molds or yeasts that cause fermentation. That is why paraffin is not considered safe to use on jams. So, it really may not be something called sugar haze. I think it is the start of spoilage microorganisms.