Syrup “honey”

[Tony Slater]

The honey bee has 3 variants of alpha-glucosidase (invertase) in 3 locations (ventricle, hemolymph, and hypopharyngeal glands). It is the latter, alpha-glucosidase III found in the hypopharyngeal glands, that is naturally transferred to honey. This invertase is not present in nurse bees, so age is a limiting factor in honey production or the ability to process nectar.

Thanks, that’s helpful. So when a bee is taking syrup from the feeder into its honey stomach, it is involuntarily mixing invertase - other enzymes - with it and the sucrose is being broken down into glucose and fructose. Its then stored in comb and dehydrated in the normal way, presumably down to 18% water (or thereabouts).

I think this is all accurate. So, m

 

[JamezF]

I agree with your reasoning. However, if I understand correctly, the way the molecules are positioned/shaped in corn syrup caused differences in the way it is digested. I have heard from other beekeepers that corn syrup can cause gut issues for bees although it is not very significant. I am currently studying organic chemistry so I am going to give this a deeper look.

There is possibly a precedent for this and if you're studying organic chemistry you may be aware of it. For example, to the best of my recollection, the chemical responsible for the smell of both oranges and lemons is limonene. In both instances the chemical is the same -- same atoms, same bondings and so on. But the two fruit smell different. That's because in each case the molecule is the mirror image of the other and our olfactory system responds differently depending on the "handedness" of the molecule. My son (who is doing some research into this for his MSc.) tells me that some drugs work the same way, so it can be that for example the "right-handed" form of a molecule is effective as a treatment whilst the "left-handed" form (which is otherwise chemically identical) does nothing.

I guess it's possible that something along the same lines is at work in the case of corn syrup?

James

 

[Dr. Abe]

There is possibly a precedent for this and if you're studying organic chemistry you may be aware of it. For example, to the best of my recollection, the chemical responsible for the smell of both oranges and lemons is limonene. In both instances the chemical is the same -- same atoms, same bondings and so on. But the two fruit smell different. That's because in each case the molecule is the mirror image of the other and our olfactory system responds differently depending on the "handedness" of the molecule. My son (who is doing some research into this for his MSc.) tells me that some drugs work the same way, so it can be that for example the "right-handed" form of a molecule is effective as a treatment whilst the "left-handed" form (which is otherwise chemically identical) does nothing.

I guess it's possible that something along the same lines is at work in the case of corn syrup?

I did not know that differing enantiomers (Left hand and Right hand) cause the differences in the smell of oranges vs. the smell of lemons. I absolutely understand that concept and was actually learning more about it in Organic Chem class today. And yes, that is a very important concept in the drug industry. Sometimes one sided enantiomer may fight a ailment while the other side actually fights a person's cells. This must be known before drugs are produced and used.

Regarding sugars, I am not sure that this is what causes the differences between corn syrup and sugar water. However, the way in which the carbon is bonded in glucose chains makes a big difference. Glucose polymer chains are normally called starch. If the carbon is bonded in a specifically different way, then those chains of "glucose" molecules are actually cellulose such as cotton or wood fiber. The mirror images could possibly be a factor but I believe there are other differences that are more important.

I do know that sugar contains mostly sucrose. Sucrose is a molecule that is simply a combination of glucose and fructose. Because of that, is is called a disaccharide and is not as quickly absorbed into life systems in comparison to glucose and fructose (monosaccharides). Nectar is a combination of glucose, fructose, and sucrose. A difference that I see between sugar and regular corn syrup is that while sugar contains fructose and glucose, corn syrup is just pure glucose. However, high fructose corn syrup has both glucose and fructose. I really would need to better understand honey bee metabolism of sugar to know whether there is any serious differences in the way they use corn syrup vs sugar water.

The following link offers some very interesting information regarding what nectar really is. Sweet solutions: nectar chemistry and quality

 

[fian]

I have read the article and only at the end does it offer a key that we beekeepers should take into account. "When a bee arrives at the hive, the concentration of sugars is usually double that of the original nectar."
Thus, we must understand the two basic processes that modify this value:
A. The energy expenditure of the flight that reduces the concentration of sugars.
B. Bees expose the nectar to the air through regurgitation in order to reduce its water content, since for the same capacity of the honey stomach, concentration is a key factor to compensate for the expense of collection.

 

[fian]

The solubility of glucose, fructose and sucrose in water at 25°C is 910, 4000 and 540 gr/L. It is also useful to remember that the hydrolysis of sucrose releases energy and that a sucrose solution held between 50-60°C is 85% dissociated.
On the other hand, for humans, the processing of glucose and fructose is not the same and therefore, although the chemical formulation is the same, the internal balance is different. I don't know if it is the same in bees.