Wikipedia:Reference desk/Archives/Science/2020 September 26

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September 26[edit]

What's the lowest specific gravity recorded for a drinkable wine?[edit]

What's the lowest specific gravity recorded for a drinkable wine? Also, could it be that a wine will have as low gravity as 960-965 or around it? (according to google the normal range is between 992-996, but I didn't find more information regarding my question) ThePupil (talk) 01:41, 26 September 2020 (UTC)[reply]

That would have a 20% or more alcohol concentration, which yeast does not make in wine.[1] If you heated up your wine, perhaps you could get the density that low. Graeme Bartlett (talk) 01:45, 26 September 2020 (UTC)[reply]
The requirement for 20% or more alcohol is based on the assumption that only alcohol affects the density, or there are other factors that have an effect on the final specific gravity?--ThePupil (talk) 02:14, 26 September 2020 (UTC)[reply]
In closed container that won't explode of course. Sagittarian Milky Way (talk) 01:54, 26 September 2020 (UTC)[reply]
If you check out the reference I gave, you can see there is quite a difference due to temperature. But supercritical wine could be quite low in density. Yet another way to lower density is via bubbles - EG carbonated wines. Graeme Bartlett (talk) 06:31, 26 September 2020 (UTC)[reply]
And maybe if you heat it in an open container fast enough it won't evaporate more alcohol than water fast enough to prevent temporarily reaching 960. Sagittarian Milky Way (talk) 13:59, 26 September 2020 (UTC)[reply]
Fortified wine can have up to a 20% ABV, in the EU even up to 22%. For lower ABV values, the wine has to have a high percentage of ether and ester components, which in low percentages are what (next to sweetness from sugars and tartness from acids) give wine its specific nose. I have no idea how high up this can go before it becomes so overwhelming that it turns the wine undrinkable, or makes one pass out by sniffing it.  --Lambiam 08:59, 26 September 2020 (UTC)[reply]
You can mitigate acid fault through Malo-Lactic fermentation (MLF) which converts Malic acid into Lactic acid. Lactic being more pleasant. Although I've drunk both acids and they weren't too nasty.
You'll typically get more acid from grapes that have lower sugars. Sugar in grape juice is measured by its refraction relative to distilled water, the unit for this is Brix.
From my brief time in the Southern California wine industry, I recall 18-23 brix being a good range for white wines and around 24 for red, although for heavier GSM blends maybe up to 28 brix could be possible given a strong season.
There's a relationship between sugars and alcohol, and therefore specific gravity, so perhaps you could look at the brix levels for different regions to work this out.
For low sugar/alcohol my guess would be sparkling Syval Blanc from Northern England, without added fructose. Alsace is a low-brix region in bad seasons, but I know they often add sugar. Higher sugar/alcohol regions would probably be ones in Australia growing grapes like Shiraz etc
Being drinkable is a bit subjective, for instance some people find the creamyness from oak-exposed Chardonnay nice, whereas others massively prefer Chardonnay that's only ever been in steel vessels. Regards, Zindor (talk) 16:18, 26 September 2020 (UTC)[reply]
And some of us have never found a wine that could be considered drinkable at all. --Khajidha (talk) 03:16, 27 September 2020 (UTC)[reply]
Us with better taste, that is :} 93.142.121.167 (talk) 18:53, 27 September 2020 (UTC)[reply]
I always laugh at people who say "you have the taste buds of a child" and things like that, because apparently bullying and peer pressure are more mature than liking tater tots. --Khajidha (talk) 15:06, 28 September 2020 (UTC)[reply]

Jumping ability of kittens compared to that of cats[edit]

At what age is the jumping ability of kittens 99% from that of mature cats? Thanks.--109.166.129.7 (talk) 18:02, 26 September 2020 (UTC)[reply]

At week 7, they can: confidently jump off of furniture and week 8: Their agility and coordination will be nearly fully developed.
  • Sullivan, Megan (Jan 22, 2018). "Kitten Development: Understanding a Kitten's Major Growth Milestones". www.petmd.com.
2606:A000:1126:28D:ADC6:7A08:1D3C:354B (talk) 19:18, 26 September 2020 (UTC)[reply]
That page only addresses jumping down, though. --174.89.48.182 (talk) 20:32, 26 September 2020 (UTC)[reply]
Has this author or the other veterinarian authors mentioned at the site written something about the development of kittens beyond the 8th week, like around 14-15 weeks? The context of the previous question is given by having watched a kitten of about 14 weeks who seems not to be able to jump a height jumpable by mature cats (like its mother) in order to reach roofs in the yard of a house nearby where it has been living in the past 2-3 months, accidentally sometimes falling from the mentioned roofs, but succeeding in getting back on roofs (with or without mother cat's help) by going around the yard where the walls are easier to climb due to lower height than the height of falling and to additional supporting elements on the wall that facilitate climbing and not jumping like metal wires and/or brick contours. But in the past 3-4 days it has not been able due to some unknow factors to get back on roofs, thus remaining at ground level and crying after midnight or early in the morning and hiding during the day, now that at this age its mother is no longer very present around it to guide it in case it has forgotten how to go around the walls of the yard for an easier climbing.--109.166.129.7 (talk) 21:05, 26 September 2020 (UTC)[reply]
There's a discussion by non-professionals about a 22-week-old kitten with similar problem (here). It could just be reluctance due to a previous mishap. Or (less likely) it could be related to something like Cerebellar hypoplasia (non-human). "I'm not a veterinarian but a play one on Wilipedia." 2606:A000:1126:28D:ADC6:7A08:1D3C:354B (talk) 03:14, 27 September 2020 (UTC) ... In the 1st case, mom will probably work things out; you can boost its confidence by encouraging it to make progressively longer/higher jumps. You should check to see if it limps or is otherwise impaired. As always: "consult a professional" (rather than random folks on the internet). [04:00, 27 September 2020 (UTC))][reply]
It doesn't limp or seem impaired. It is an outdoor kitten from the neighbouring house that can be seen from my apartment window so I can't do much to help it with jump encouragement. It has just come out of hiding, but has returned to the unknown/unspotted hiding place after trying to follow him.--109.166.129.7 (talk) 10:57, 27 September 2020 (UTC)[reply]
I've just seen the mother cat of the kitten at the usual spot on the roof of the kitchen from the yard where there is a small window where the people from the house put some food and water for outdoor cats. It seems that the timing of encounter has been missed, it would have been an interesting moment to see whether the mother on the roof would do something when hearing the kitten (at this age) crying for help at the ground level near the wall of the house kitchen.-- 109.166.129.7 (talk) 11:33, 27 September 2020 (UTC)[reply]
You might get better answers on pets.stackexchange.com. —Tamfang (talk) 00:57, 29 September 2020 (UTC)[reply]
Thanks for the suggestion, I'll also try there. Still, it seems that there aren't to much data about height - age tables for kittens.--109.166.135.35 (talk) 23:54, 30 September 2020 (UTC)[reply]