Wikipedia:Reference desk/Archives/Science/2017 August 11

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August 11

Why do vanilla ice cream manufacturers have to color the vanilla ice cream?

I think vanilla ice cream is supposed to be white. I made vanilla ice cream in chemistry classes, using two methods. One method was to lower the temperature of the ice in the plastic bag with salt by shaking. Another method was to use liquid nitrogen on the cream. The only ingredients used were half and half cream and vanilla extract. The finished result looked white. Why can't ice cream manufacturers just make the ice cream look white? Why do they add annatto for color? 50.4.236.254 (talk) 01:46, 11 August 2017 (UTC)

Because pure white is a very fragile tone, set off by the tiniest portion of a color, like in Aquarelle starting on a clean white paper. In contrast adding very cheap beta-Carotene for color causes an orange tone which is most appealing and a very good disguise especially for tone setoff's naturally caused by aging (Rancidification) which also usually causes an orange tone. --Kharon (talk) 02:46, 11 August 2017 (UTC)

Milk looks white. Ice cream is derived from milk. So, why is it cheaper to add a color than to keep it the way it is? 50.4.236.254 (talk) 03:10, 11 August 2017 (UTC)

Its not cheaper than not adding anything ofcourse but beta-Carotene is very cheap and very little of it is needed to get the orange on top. They simply dont want to sell white ice cream for multiple reasons and add beta-Carotene for multiple reasons. You cant make ice cream more appealing and cheap any other way. --Kharon (talk) 03:34, 11 August 2017 (UTC)

Note: Real vanilla isn't white, but is rarely used in common ice-cream today, to reduce production costs (more than retail cost). Likewise, real cream is only used in the costly brands, but was also traditionally off-white. If the goal was to make the icecream very white, there would be other options like titanium dioxide. —PaleoNeonate – 03:39, 11 August 2017 (UTC)

What do you mean by "costly brands" and "real cream"? In NZ, Tip Top (ice cream) the retail price where I live in Auckland for a 2L tub of ice cream tends to be $4.50-5.50 although occasionally is available for $4. This would be considered by most to be ordinary ice cream, not the real premium or fancy ones which come in smaller containers and tend to be twice as much or more per L. It's also sold as ice cream meaning it I presume meets the legal requirement of [1] "consisting of not less than 100g/kg of milk fat". (Tip Top also has 55% of the market share in NZ [2], not just from their tubs of course.) By comparison, Much Moore (formerly Kiwi) Marvels brand products are generally $3.80-$4.50 for 2L. Some products under their Marvels brand are ice cream, some are frozen dessert (i.e. either don't have any cream, or don't have enough to meet the legal requirement to be called ice cream in NZ/Australia). Some cheaper products which are I believe all frozen dessert are generally $3.29-$3.79. The Much Moore 'premium' range, which is still just sold in a normal 2L tub is generally $4.30-$5 (sometimes, more often than Tip Top $4) and I believe is all ice cream. Other products tend to be similar price ranges and many of them are ice creams. Admittedly not all ice creams use something which may be called cream in their production, e.g. I believe the Much Moore Marvels range uses milk solids but the point remains most or all of the fat is milk fat. In any case, Tip Top ones do say they use cream e.g. [3]. Some may also use thickeners for various reasons. Nil Einne (talk) 07:28, 11 August 2017 (UTC)

Forgot to mention that Tip Top is of course nowadays owned by Fonterra Co-operative Group one of the largest dairy countries in the world (and who by their dairy coop nature are mostly focused in dairy products, unlike say Nestlé which is a general food and beverage company, or likewise Danone) , so it's not particularly surprisingly they generally use cream or otherwise use milk fat. Nil Einne (talk) 15:30, 12 August 2017 (UTC)

• Most of the vanilla ice cream I've seen is cream-colored, which is to say very pale yellow. On occasion I have seen the heavy yellow vanilla, which is associated here with cheap store brands. Is the yellow ice cream you guys get the norm outside the US? Abductive (reasoning) 06:23, 12 August 2017 (UTC)
  • Vanilla is cream-coloured; that is, it's not pure white. I wouldn't refer to it as yellow. Maybe you're confusing it with the unique NZ variety of ice cream called hokey pokey. Akld guy (talk) 09:26, 12 August 2017 (UTC)

Note that French vanilla ice cream adds egg yolks, making it more yellow: [4]. This is considered a premium version, so it's not surprising cheaper vanilla ice creams may be made to imitate it. StuRat (talk) 16:16, 12 August 2017 (UTC)

Vanilla ice cream is generally yellowish in the UK. Only the very cheap stuff is white. Wall's Ice Cream is probably the market leader here; it lists "Colours (Annatto, Curcumin)" amongst the ingredients, but no actual vanilla. Alansplodge (talk) 17:22, 12 August 2017 (UTC)

Interesting. There seems to be regional variations. Abductive (reasoning) 18:54, 12 August 2017 (UTC)

Metabolism of high-fiber food

I don't understand how dietary fiber affects metabolism and how it affects the stated calories in package labeling in the US.. Consider a bean dish (Gefen Cholent Mix) in which one portion is supposed to provide 70 kilocalories of energy, with 0 fat, 23 grams of carbohydrate, which includes 13 grams of dietary fiber, and 8 grams of protein, per the package's nutritional label. Each gram of carbohydrate should provide 4 kilocalories, as should each gram of protein. The 31 grams of combined carb and protein should provide 124 kilocalories rather than the stated 70 kilocalories. If the 13 grams of fiber (presumably not metabolized by humans) are deducted from the 23 grams of carb, then there would be 18 *4=72 kilocalories of energy per serving., 3% more than the stated amount. Would 23 grams of carbohydrate be converted into glucose in the bloodstream. or would only 10 grams of carbohydrate be converted into glucose? This would seem to be a big deal vis a vis the amount of glucose which enters the bloodstream after such a high fiber meal. Edison (talk) 03:52, 11 August 2017 (UTC)

That's presumably because, as stated in Food energy#Nutrition labels, energy is estimated, and obviously the labeling authorities do not care for few % difference, as they themselves use an official table were, for foodstuff, 4 cal = 17 kJ instead of 16.736 kJ that a physicist would use, that's a 1.5% difference. Add some rounding issues and tolerated variations in content: things will quickly add up to 3% difference you noticed.

Gem fr (talk) 10:05, 11 August 2017 (UTC)

Calories are generally rounded off to the nearest 5 Calories (kcal), which means that for any food greater than 60 Calories (kcal) the 3% would be statistically insignificant, as it would have been rounded off. In the example above, 2 kcal is within the rounding, so it was just rounded off. Statistically speaking 72 and 70 are identical when you're rounding to the nearest 5. --Jayron32 14:50, 11 August 2017 (UTC)

Fiber is metabolized by humans, the USDA gives a value of 2 kcal per gram. Abductive (reasoning) 06:25, 12 August 2017 (UTC)

That depends on if it's soluble fiber or insoluble fiber. StuRat (talk) 16:20, 12 August 2017 (UTC)

Presumably the 2 kcal/g is an average...Abductive (reasoning) 18:52, 12 August 2017 (UTC)

Hmmm, the wiki article says that what matters is whether the fibers are broken down by bacteria and then absorbed by the body, the energy content is then attributed to whatever the body will absorb and metabolize. However, the breakdown of fibers in the gut also releases energy and this is not accounted for at all. Count Iblis (talk) 19:29, 12 August 2017 (UTC)

Eat fewer Calories to lose the weight or eat the same amount or greater Calories to build muscle and thus increase metabolism?

On one hand, people recommend to the general public to eat less. On the other hand, athletes are recommended to eat more to complement the intensive physical activities. Okay, what happens if an overweight person doesn't want to lose weight so he eats the same amount of food (or more, not less) and adds an intensive strength-training and aerobic exercise (such as doing push ups and running) to nourish muscle growth? 140.254.70.33 (talk) 16:32, 11 August 2017 (UTC)

He has better health outcomes. Well, possibly not him, because of individual variability, but if you got some statistically large enough sample of such people, a significant portion of them would have a better quality of life.[5] --Jayron32 17:38, 11 August 2017 (UTC)

You have to note here that being able to burn a significant additional amount of calories compared to the total calorie intake requires being very fit to begin with. E.g. a 60 kg man running fast for an hour will burn roughly 1000 Kcal more due to this exercise. But you won't be able to do this unless you have excellent cardio fitness. Strength training burns only a small amount of energy. That's why body-builders do some cardio training besides the massive amount of strength training. Count Iblis (talk) 17:58, 11 August 2017 (UTC)

A doctor I do research with began his research with an interest in football and studied obese linemen. They are clearly obese, yet they exercise extensively. So, are they healthy? No. Obese NFL players tend to have cardiometabolic syndrome. After retirement, that quickly leads to hypertension, diabetes, and hyperlipidemia, all of which quickly lead to life-ending problems such as congestive heart failure or renal disease. There is a lot (more than you'd think) research on obesity in the NFL, which gets right to the issue of obesity and exercise. Check scholar.google.com. 209.149.113.5 (talk) 19:31, 11 August 2017 (UTC)

I would say that they were not obese when they were athletes, as then the weight was mostly muscle. But, yes, ex-athletes do tend to continue to eat as much, but get less exercise, turning that muscle into fat, at which point they become obese.

As for them being "clearly obese", that sounds like you are only looking at weight, not muscle and fat percentages, although there are some "athletes", like sumo wrestlers, who really are obese. StuRat (talk) 21:55, 11 August 2017 (UTC)

Indeed. Count Iblis (talk) 23:37, 11 August 2017 (UTC)

It is preseason. Watch an NFL game. That flab on the linemen is not muscle. It is fat. They are obese. 71.85.51.150 (talk) 00:40, 12 August 2017 (UTC)

Yes, it is possible that they get "out of shape" between seasons, then "shape up" at the start of the next season. One problem with massive muscles is they take massive exercise just to maintain. Otherwise, they are replaced by fat. StuRat (talk) 01:05, 12 August 2017 (UTC)

As far as I can tell, the 71 IP is not suggesting that linemen have fat not muscle only preseason. I'm not sure why they mentioned preseason but I think they're suggesting perhaps people have forgotten what linemen look like since it's preseason so they should go back to a (non preseason) NFL game. Even if the IP was suggesting that the flab on linemen was fat and not muscle only during pre season, I seem no reason to think that is correct.

I'm under the impression the NFL is a professional sport where atheletes are often paid multimillion dollar salaries. I'm not sure if those salary ranges apply to linemen but at a minimum I'm assuming their positions are still highly competitive. In general, while professional athletes may lose a bit of fitness during the early parts of an offseason, they can't afford to let themselves go as badly as you suggest because they won't be able to recover in time for the season and will find themselves not very popular with the people who can significantly affect their careers like coaches.

According to [6]/[7]/[8]/[9] the average body fat percentage for offensive and defensive linemen was 24.8%. Okay this is for high school and NCAA football players and was during an off-season training season and high school was 26.1% and college was 22.9%. However none of the authors expressed any concerns these players had really let themselves go so they weren't looking at a good sample. (I'd also note that when in the off-season is unspecified. Even if you believe that athletes can get very bad during the first month or so of the off-season, you've surely, I hope, got to realise a month before the season starts athletes need to be close to their peak condition.)

This [10]/[11]/[12] looked at NFL players and suggests offensive line has an average body fat percentage 25.1%. It also says:

The only exception was observed with the offensive line, where values for BMI were higher, accompanied with the classification of ‘‘poor’’ in health estimation, but the %body fat still did not represent extreme values as noted by the BMI.

The extreme here is likely referring to the fact that BMI show them to severely obese category but clearly whether you want to call them obese or not their body fat percentage has reached levels not considered healthy in the general case. Again this was during a summer training camp, prior to the start of the season. I'm not sure how far away the season was, but the authors seem to have similar thoughts to mine:

As such, we felt that each player would be in top condition after an off-season conditioning program and summer minicamps.

Next there's [13] which has results for the 2006 – 2013 NFL Combine testing using Bod Pod and gives 24.6% average body fat for offensive line. Admitedly I'm confused what the source for these figures actually is since that says it's from “Current Assessment of Body Composition in Sport” but I can't find that source. Other places says it's in Sports Med 42(3) but the closests thing there is [14]/[15] "Current Status of Body Composition Assessment in Sport". Anyway I would guess it's just a typo or maybe the title was renamed after pre-release. But more importantly, AFAICT that source doesn't have such figures nor does it have any additional data. And considering it was published in 2012 it would seem weird for it to have 2013 figures. Still the BodPod is definitely used as part of the combine [16] so probably they are somewhere.

Anyway assuming we can trust in-thinair.com to accurately report the figures, wherever they were published, I presume this means the NFL Scouting Combine so technically this is off season too. But considering what the NFL Scouting Combine is for....

Either the athletes go 'you know what, the combine is coming up but I don't have to be in peak condition because it's offseason so let's not worry that this moment could make or break my life and if I was only able to keep it I'll be much more impressive since after all at least the next dude will have the same attitude as me so while I may not be better than them even though I could be, I won't be worse'. And the coaches, scouts etc say 'hey that guy is fat, but I'm sure he just let himself go in the offseason and will regain it over the next few months, let's not worry about our experience or the whole purpose of this combine; you know as that person on the RDS said, it's normal for people to let themselves go so badly out of season.'

Or these people are in top condition for assessment during the combine. (Of course it's possible that being fat is seen as impressive by observers during the combine, but is actually bad while playing but this seems to make further weird assumptions.)

Nil Einne (talk) 06:30, 12 August 2017 (UTC)

BTW, I noticed [17] in my research but it doesn't directly relate to the body fat percentage issue although I just noticed it does mention an absolute weight limit at college level which may affect the earlier figures. Looking a bit more it seems that the size of linemen is a concern in both American [18] and Canadian [19] football. I'd note that the middle source claims as those the earlier links, as well as the middle source just now both claim the linemen size has significant increased over the past few decades. Although interesting [20] it could be going down again, for reasons unrelated to health concerns. Also about Bod Pod and similar measurements, I should mention that one thing the Sports Med source does say backed by an RS is is that such devices tend to underestimate body fat for college football players (I assume this is American, or maybe Canadian since I don't think anywhere else would refer to college football players) by an average of 2%. So assuming the above figures are unadjusted, they may be a little on the low side. Although an average of 2% needs to be taken with caution if we're talking about people with fairly different body types depending on their precise position, which the differing body fat percentages suggest is the case. 07:05, 12 August 2017 (UTC)

Maintaining that level of muscle mass during the off-season would require that they exercise just as much as they do during the regular season, which is basically a full-time job. So, it's not exactly being lazy to not keep up. Do you do the same amount of work when on vacation as when at work ? StuRat (talk) 16:26, 12 August 2017 (UTC)

I mentioned that it was the preseason to indicate that it is very easy to find a video or even a photo of an NFL lineman right now. Look at Dontari Poe. There is a photo of him, during the season, when he is "in shape" right on the page. Look at his lower abdomen. That is not muscle bulging out. That is fat. Yes, he does have a lot of muscle. He also has a lot of abdominal fat. That is the norm for linemen. They have a lot of abdominal fat. You have to be very stubbornly ignorant to look at the photo of Dontari Poe and think that his spare tire is all made of muscle. I would like to have more examples right here on Wikipedia, but I've noticed that there is a distinct lack of uniform photos for linemen. I checked Albert Haynesworth, Jerome Bettis, Dan Wilkinson, etc... I didn't even go after other positions, such as Jared Lorenzen, who I believe is the most obese quarterback ever signed in the NFL. I feel that only someone who has never watched an NFL game can claim that linemen are not obese. However you want to measure obesity, when your belly is hanging inches over your belt, that is fat, not muscle. I'm not saying it to fat shame. I am trying to point out that those players are exercising daily. They are athletic. They have a lot of muscle. But, they are still obese and they still have obesity-related diseases. 71.85.51.150 (talk) 18:41, 12 August 2017 (UTC)

They exercise, but not like this. Count Iblis (talk) 18:50, 12 August 2017 (UTC)

It may be interesting to note that Dontari Poe (the example above) is being offered half a million dollars to reduce body fat with the Falcons this year. He reportedly made the first $100k so far. 209.149.113.5 (talk) 14:07, 14 August 2017 (UTC)

• See an endocrinologist who specializes in weight loss/body mass index. There are various metabolic disorders as 209 noted that you cannot self diagnose, and we certainly cannot diagnose. He can recommend a nutritionist and medication. Then folow his advice on exercise, under a licensed trainer. Don't ask for medical advice here. μηδείς (talk) 21:47, 11 August 2017 (UTC)

Is any new research still done with optical microscopes?

If not, what was the last time it was? Sagittarian Milky Way (talk) 17:26, 11 August 2017 (UTC)

This very day, I'm quite sure my wife used one. She's a forensic scientist who does microscopy as a daily part of her job. She uses a regular old, binocular optical microscope fitted with a camera to record what she sees for evidence. The McCrone Research Institute is probably one of the major players in microscopy in the U.S., and still does work with all sorts of work with light microscopy. So the last time they did active research in the field is quite likely right now. --Jayron32 17:35, 11 August 2017 (UTC)

Probably 95% or research in medicine, biology. geology, etc is done with optical microscopes. --AboutFace 22 (talk) 19:19, 11 August 2017 (UTC)

They certainly are important, but that number is too high for medicine. Don't forget about the vast amounts of work done with molecular biology techniques, and things like Western blots, flow cytometry etc etc. I know a fair few people in neuroscience who never get near a microscope. They are a minority, for sure, but they are more than 5%. Even I, a regular microscope user in neuroscience, don't do 95% of my research on them, I do too many qPCRs for that! Fgf10 (talk) 23:46, 11 August 2017 (UTC)

We used light microscopes daily in my old lab, for everything from insect ID to counting pollen. I think maybe you are undervaluing how useful it is to see little things across many, many fields of inquiry. Nobody in my old lab ever published new research specifically about a new thing that they found with a light microscope, but they certainly published new research that could not have been done without a microscope.

If you want an example of new things recently discovered with a light microscope, check out this [21] coverage of a 2013 Science paper about naturally occurring gearing mechanisms. Sure, the press photo is from an electron scope, but that's just because it is easier to see, looks cool and they had the money to do it. These features are visible under relatively low power, as shown by the video at that link, which is just a normal light scope. This is top-notch, ground-breaking research that basically amounts to "We looked at this small thing with a light microscope and found something really cool that we think all scientists should know about."

TL;DR: yes, lots of research is done every day with light microscopes, probably thousands of people are doing it as I type.SemanticMantis (talk) 19:41, 11 August 2017 (UTC)

I think you meant to link here : [22]

Very cool. ApLundell (talk) 22:55, 11 August 2017 (UTC)

You are mistaken if you think that the light microscopy is some old and stagnant technology that has not changed for a long time. On the contrary new optical methods are actively being developed. Moreover some of them like the fluorescent microscopy earned their creators a Nobel prize. Ruslik_Zero 20:00, 11 August 2017 (UTC)

• You'll have to specify which optical microscope. In my neuroscience research, I use both phase contrast and epifluorescent optical microscopes essentially every day. I frequently use dissection microscopes, and pretty regularly use a confocal fluorescent microscope or two-photon microscope. Conventional bright field microscopy is not used much in my field, but certainly is in others. Take away my optical microscopes and 90% of my research is gone. Fgf10 (talk) 23:43, 11 August 2017 (UTC)

No one has mentioned that many a biological sample would be destroyed or ruined if they were prepared and placed in the vacuum of an electron microscope. Also, did Nikolaus Pevsner have to examine every brick? One uses the right tools for the job. Aspro (talk) 01:00, 13 August 2017 (UTC)