Has anybody else noticed this? This week, I have drained honey from 4 Flow frames in total. The frames were at least 90% to fully capped. I was expecting about 2 liters (2 quarts) per frame. I was wrong - the half gallon jars looked about to overflow. The Flow continued after an hour, so I ran inside and brought out some more jars. Finally the Flow ended after about 3 hours, but there wasn’t nearly as much honey per minute for the second and third hour. So is it really worth waiting for the last few drops? That is a whole different set of questions!
Per frame, I have different sized jars of honey. First jar from the frame is about 1/2 gallon (2 liters) - collected in one hour. Second jar is about a pint (a bit less than 500ml) - collected in the next one to two hours. So in total I now have 2.5 liters, but is it all the same quality? In scientific terms, they are “fractionated”, perhaps according to their viscosity?
Think about it. The less viscous (runnier) honey will flow out first. The more concentrated stuff takes longer to run out. So the first hour is the runnier honey, and the next one to two hours is the thicker stuff. But can we prove that? Enquiring minds want to know, and fortunately, I also have a refractometer.
OK, let’s cut to the chase here. The answer is that the first Flow honey had a water content of 17.5% and that was about 2 liters or 2 quarts per frame. The last pint (500 ml) or so of honey had a water content of only 16.5%. So I strongly suggest that you wait for the last few drops to drain out of your Flow hive, because your water content will drop dramatically!
Sorry if this was a bit too scientific, but these things fascinate me, and I intend to use them to improve the quality of the honey I extract.
Think about this - the honey at the bottom flows out first because the honey at the top can not get past it, not a lot to do with viscosity. What is the temp gradient in the vertical axis through the frame? if the frame is cooler the further toward the top, the honey will be less viscous. So if you wait for the lost 500ml (20%) it gives you a moisture content of 17.3% ( check my math please). not sure if you can taste the difference between 17.3 and 17.5% , but 2 hours to increase your harvest by 20% seems worthwhile and good housekeeping.
My thinking may be incorrect, I am not a scientist just a partially retired construction guy who was a contractor and I measure cost vs benefit.
We came to the same conclusion by different means
QED
cheers
In general- I want to get every last drop out! The only thing that might mitigate against that is a time constraint. Recently I harvested my hybrid super off the hive so I had as much time as I liked. the vast majority of the honey dripped out over a few hours. After that was done there was a tiny trickle so I increased the angle of the frames and left it overnight.
In the morning it was still trickling at the slowest rate imaginable. After some time I thought it was pretty much done and left the frames outside for the bees to clean up. The next day I was surprised to find several tablespoons more honey had dribbled out ever so slowly and made a puddle on the ground… bees gathered and cleaned 90% of that up… My honey is VERY thick around 16%- and it takes forever to fully drain out.
It makes sense that a percentage of the thickest honey would be end up being the last to flow out- though I think at the start a goodly amount of that would be pushed out by the thinner honey above.
I understand what you are saying. However I would suggest that there is another contributing factor, Gravity.
In the early part of the collection gravity will be pushing down on the honey, as you say it weighs about 2.5kg, ~25 newtons of force, I suspect this is enough to significantly increase the flow rate, as the honey flows out of the frame, the “weight” (actually Mass) of honey decreases and so the “Flow” decreases.
That does not explain why the Honey has a lower water content in your “last batch”, if the Water and Honey were “Moving through each other”, the honey is heavier and so we would expect to see the latter honey with a higher water content.
To me that implies that the Honey and Water, to a large extent, come out “in order”, they do not mix (much).
Which enables me to suggest that (as I believe the bees have probably “Fanned” the honey to lower the water content prior to capping) the Bees need to “Fan” so that the wettest honey is dry enough, but to an extent they may need to “Fan the whole frame”, here I make an assumption that they “Fan out of the top”, i.e the water goes away from the top cells first. But they have to keep on fanning until the “Worst” (Wettest) Cells are low enough in water content to be capped.
(I understand they cap “individual” cells so they COULD cap each cell as it is ready, but I am not sure they make such a precise calculation for each cell)
Or they find it easiest to expel water from the top cells, so kind of “overshoot” their specific target.
I’ll think on how that “wetter” mechanism you described could work.
But I am fairly convinced that your flow decreases simply because there is less honey pushing the lower honey out.