Syrup & HMFs

[Kate Atchley]

I know HMFs can be created when making sugar syrup and this is harmful to bees.

Terry Clare advises always making oxalic trickle syrup with cold water (whizzed in blender) to avoid HMFs ... partly, I gather, because of the added HMFs effect of the oxalic acid.

For feeding, I generally heat syrup as I make it to speed the process.

Can anyone explain the science and best practice re heating water/sugar when making sugar syrup from cane sugar? If some heat is okay, how much?

Kate :confused:

[gavin]

Protracted boiling may be harmful, but I just make up syrup with hot water from a kettle. The cool sugar immediately brings down the temperature and the sugar dissolves with 5-10 min of stirring. Some recommend water from the hot tap which will be less hot. OK, there are still a few stubborn crystals at the bottom but let them settle and just leave these for the next batch or discard after you pour off the syrup.

You should see some colour change if you are making up strong sucrose solutions and some of it is being converted to HMF, but some sources of sucrose have a hint of yellowness anyway.

Yes, oxalic acid accelerates the process but again you have a colour change to indicate that changes are happening. I suspect that Terry may be a little OCD there - my oxalic solutions have been warmed to help everything dissolve and they don't discolour until months later (if I keep any that long!). Also, you are applying only 5 ml to each seam of bees unlike the many litres of feed which colonies get fed.

The things that accelerate sugars being turned into HMF are acids, chemical catalysts such as bromides, and heat. Needs time too. Honey and oxalic acid solution are acidic and so convert faster - but prolonged heat is necessary to make a lot of HMF. There is a Czech paper that suggests that microwave heating of honey generates less HMF than the usual warming of honey and that may be because the heating is for a short period.

[Adam]

I make up syrup as Gavin - kettle of hot water and when it's cooled enough it's about OK to use. There's a pale straw colour to syrup. it shouldn't need re-heating. If all the sugar doesn't dissolve, I leave the sludge for next time or slosh some more water in.

I assume syrup is the same as honey - the HMF increases as a product of temperature and time. High temperature is OK for a short while. Combine high temperature AND time and you get HMF much more quickly.

For honey, it takes a while for the heat to get through to the set or setting honey in the jar so a quick zap with the microwave could well produce less HMF that the pan of hot water for re-heating or a protracted time in a warming cabinet. Especially if you forget the warming cabinet is on. Fortunately my sister-in-law and niece both like slightly caramelized honey.

[Kate Atchley]

Thanks and good ... I'll go on making syrup as I always have: short burst of heat from the hot water I pour the sugar into and briefly beneath the pan then stirring. Doesn't discolour much.

Agree with Gavin that oxalic syrup is given in such small quantities and is so light a mix that making it from cold seems rather over-cautious.

Thankfully, as yet, haven't had to use it in Lochaber though I still have stores of oxalic and formic acids brought from Edinburgh where I used to live.

Kate

[Jon]

I make up my own oxalic solution for myself and association members in the ratio of 7.5g Oxalic, 100g sugar and 100ml warm water and have not managed to kill any colonies with it yet.
We distributed about 3 litres at an association meeting last December.
This will be my 4th winter application of Oxalic.
Bees seem to be quite tolerant of it.
There has been some suggestion that a nosemic colony will be killed off quickly by the Oxalic acid but this is just bringing the day of reckoning forward a bit.

I make up syrup the same way as Gavin and Adam.

[Mellifera Crofter]

To add to Kate's question - I'm reading the Mid Bucks module study notes (http://blog.mbbka.org.uk/category/education/) for Module 1. It says to sterilise the honey by boiling it before feeding it to the bees. I only have one apiary, so I don't do that. Does anybody here actually boil their honey, and for how long would you boil it to be on the safe side?
Kitta

[Neils]

I, personally, would not boil honey full stop.

I also don't give honey back to bees from different apiaries.

The honey for jarring might mix, the supers don't.

While I think honey is better for the bees, I would not take honey from one apiary to feed another.

[Mellifera Crofter]

Thanks Nellie. I think I'll also say, "I won't boil, full stop" - particularly as I only have one apiary.
Kitta

[gavin]

Apart from the change in the quality of the food for bees, I would doubt that boiling would effectively deal with AFB spores.

[Trog]

Given that sugar and water are boiled to a high temperature when making candy, is this now considered dangerous due to HMFs?

[Poly Hive]

I buy my fondant pre made and with all the ails and ills in the world to consider HMF due to making candy/fondant is not high on my list. Candy has been made for a good 100 years and the bees are still with us aye?

PH