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The chemical secrets that help keep honey fresh for so long

bbc.com

91–100 of 173 posts

Re: The chemical secrets that help keep honey fresh for so long

#91
post #30

Same principle, reducing water activity (aw), is how Nutella keeps fresh for so long without refrigeration: its water activity is even lower than honey. Most bacteria need an aw of around 0.85 to thrive, Nutella’s aw is around 0.4, honey’s around 0.5-0.6. Peanut butter is 0.7, so it stays fresh for relatively long, too. Here’s the definition of water activity from FDA: https://www.fda.gov/inspections-compliance-enfor…

This is something that I think about sometimes. Life on Earth has had billions of years and expanded to fill so many niches, but they're nearly all damp niches. Nothing has ever really managed to really thrive in deserts. Sure, there are a few cacti, succulents, a bit of scrub, a few palms and rodents and a few birds that eke out an existence. But really it's mostly barren, compared to temperate or tropical climates where nature takes over land entirely within years. Yes, the soil in deserts is poor, but that's a consequence: it was poor everywhere before plants conditioned it. It's just that evolution has never in a billion years hit on a way to capitalise on all that sunlight and those day/night temperature gradients without enough water to float all the microbiology in.

Probably just as well (invoke some kind of anthropic principle here if you like) or we'd have, say, fungus there can quickly eat dry things and storing food or building anything with longevity would be much harder.

Re: The chemical secrets that help keep honey fresh for so long

#92
post #89

Earlier quoted context omitted.

I've recently been embracing the idea of co-evolutionary pressure. Reading the article I thought that if it was just the dryness, bacteria would have evolved to tap such a rich energy source. Hence the biology of bees must have something to do with the preservative nature of honey. I'm feeling vindicated!

I think co-evolution should be investigated for encoder-decoder architecture training. The idea being that you pair multiple decoders with each encoder, and multiple encoders with each decoder (randomly sample if large populations). The selective pressure is a feedback loop between the encoder and decoder populations that requires the members to produce and interpret the latent vector as well as possible. In theory,…

I remember playing around with RapidMiner about 10 years ago and it had a hyper parameter optimizing primitive that uses evolutionary search. It was quite pleasing. RapidMiner doesn't do any of the modern stuff though. Asking chatgpt turns up mostly pretty old (abandoned) projects from around 2017.

Re: The chemical secrets that help keep honey fresh for so long

#93

This article is missing what I think is a pretty important PSA on the topic of bacteria in honey: Honey commonly contains small amounts of the anaerobic bacteria Clostridium botulinum, which causes botulism. This is why you should not feed honey to infants, because their immune systems cannot safely handle any amount of it yet. Even though the levels apparently are small enough for the rest of humans to consume worry…

same with immunocompromised folks, though all that only applies to raw honey; pasteurized honey is more common in grocery stores and totally safe

Pasteurization would also destroy the delicate honey taste. It takes almost nothing to do that, and heating honey above about 40 C even for 30 seconds will kill any honeyness and all you have left is the sweet.

I'll bet only the imported Chinese honey is pasteurized on the supermarket shelf. Most of that goes to industrial use anyway.

Re: The chemical secrets that help keep honey fresh for so long

#94
post #30

Same principle, reducing water activity (aw), is how Nutella keeps fresh for so long without refrigeration: its water activity is even lower than honey. Most bacteria need an aw of around 0.85 to thrive, Nutella’s aw is around 0.4, honey’s around 0.5-0.6. Peanut butter is 0.7, so it stays fresh for relatively long, too. Here’s the definition of water activity from FDA: https://www.fda.gov/inspections-compliance-enfor…

This is something that I think about sometimes. Life on Earth has had billions of years and expanded to fill so many niches, but they're nearly all damp niches. Nothing has ever really managed to really thrive in deserts. Sure, there are a few cacti, succulents, a bit of scrub, a few palms and rodents and a few birds that eke out an existence. But really it's mostly barren, compared to temperate or tropical climates…

Cacti aswell, mostly thrive because of desert floods. They've evolved to quickly suck up as much water as they can, then they use a special acidic form of photosynthesis to make it last as long as possible.

Different desert plants use similar ideas, the Aussie outback for example blooms for about a month after a given flood, reproduces, then dies out near completely except around the occasional waterhole.

Re: The chemical secrets that help keep honey fresh for so long

#95
post #85
post #57

Earlier quoted context omitted.

It's pasteurised to stop you from making mead, not because it does anything to Clostridium spores.

Pasteurization doesn't in any way prevent honey from remaining fermentable.

OK. So?

Re: The chemical secrets that help keep honey fresh for so long

#96
post #30

Same principle, reducing water activity (aw), is how Nutella keeps fresh for so long without refrigeration: its water activity is even lower than honey. Most bacteria need an aw of around 0.85 to thrive, Nutella’s aw is around 0.4, honey’s around 0.5-0.6. Peanut butter is 0.7, so it stays fresh for relatively long, too. Here’s the definition of water activity from FDA: https://www.fda.gov/inspections-compliance-enfor…

This is something that I think about sometimes. Life on Earth has had billions of years and expanded to fill so many niches, but they're nearly all damp niches. Nothing has ever really managed to really thrive in deserts. Sure, there are a few cacti, succulents, a bit of scrub, a few palms and rodents and a few birds that eke out an existence. But really it's mostly barren, compared to temperate or tropical climates…

More counterintuitively: why hasn't any major bacteria evolved to feast on lipids like oils? Much denser source of energy than desert dirt.

Re: The chemical secrets that help keep honey fresh for so long

#97
post #82

Earlier quoted context omitted.

Millions of years!

The fact that they navigate by memorising visual landmarks like trees, buildings, and flowers to recognise familiar routes is unbelievable

Amazing what well trained small neural networks can achieve.

Re: The chemical secrets that help keep honey fresh for so long

#98

Earlier quoted context omitted.

This is something that I think about sometimes. Life on Earth has had billions of years and expanded to fill so many niches, but they're nearly all damp niches. Nothing has ever really managed to really thrive in deserts. Sure, there are a few cacti, succulents, a bit of scrub, a few palms and rodents and a few birds that eke out an existence. But really it's mostly barren, compared to temperate or tropical climates…

More counterintuitively: why hasn't any major bacteria evolved to feast on lipids like oils? Much denser source of energy than desert dirt.

https://en.wikipedia.org/wiki/Lipophilic_bacteria

Re: The chemical secrets that help keep honey fresh for so long

#99
post #45

I’d be curious to see if similar principles could be applied to non food preservation. Nature’s solutions often scale better than synthetic ones, especially when stability over long timeframes is needed.

Honey's hydrogen peroxide production and hygroscopic properties have already inspired antimicrobial coatings for medical devices and water-resistant biomaterials for tissue engineering.

Re: The chemical secrets that help keep honey fresh for so long

#100
post #30

Same principle, reducing water activity (aw), is how Nutella keeps fresh for so long without refrigeration: its water activity is even lower than honey. Most bacteria need an aw of around 0.85 to thrive, Nutella’s aw is around 0.4, honey’s around 0.5-0.6. Peanut butter is 0.7, so it stays fresh for relatively long, too. Here’s the definition of water activity from FDA: https://www.fda.gov/inspections-compliance-enfor…

This is something that I think about sometimes. Life on Earth has had billions of years and expanded to fill so many niches, but they're nearly all damp niches. Nothing has ever really managed to really thrive in deserts. Sure, there are a few cacti, succulents, a bit of scrub, a few palms and rodents and a few birds that eke out an existence. But really it's mostly barren, compared to temperate or tropical climates…

If there were an evolutionary advantage for more things to being in an arid region over being in a place with abundant, easily accessible water, I reckon the niche would have been filled. the natural world isn't really "interested", for lack of a better term, in maximal efficiency outside the context of following the path of least resistance in any given domain. Lightning might strike your chimney even tho there's a giant metal tower 300 feet in the air a quarter mile down the road that appears to be a much better path to ground.
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