Speaker 1: Welcome to Stuff to Blow Your Mind production of My
Speaker 1: Heart Radio. Hello, and welcome to Stuff to Blow Your
Speaker 1: Mind Listener Mail. My name is Joe McCormick. My regular
Speaker 1: co host, Robert Lamb is out today, so I'm going
Speaker 1: to be recording this episode. Sol one announcement. Rob and
Speaker 1: I are both going to be out the rest of
Speaker 1: this week and the very beginning of next week. So
Speaker 1: we've got some vault episodes lined up for you starting tomorrow.
Speaker 1: But I should be back with all new listener mail
Speaker 1: on Monday then, and we'll have other new episodes for
Speaker 1: you sometime that week, I believe on Wednesday. So right
Speaker 1: on to your messages. This first message comes from Raphael
Speaker 1: and it's a response to our episodes on t Rafael says, Hello,
Speaker 1: Robert and Joe. I just finished part three of your
Speaker 1: Exploration of Tea, and I wanted to say I really
Speaker 1: enjoyed these episodes. I'm not a big tea drinker, though
Speaker 1: various tea varieties seem to proliferate in our kitchen cabinet.
Speaker 1: That said, Rob's poetry readings made me brew a cup immediately.
Speaker 1: As a food scientist, I always appreciate episodes where you
Speaker 1: get into the history, science, and culture of foods. What
Speaker 1: put the t series over the top for me was
Speaker 1: the digression in part three on the topics of reology
Speaker 1: and philosophy. This is why I love your show. I
Speaker 1: wanted to expand on a few comments you made in
Speaker 1: part two while talking about you lose preference for blue
Speaker 1: glazed teacups. Uh and plenty of the elder I couldn't
Speaker 1: agree more with your point that visual presentation can really
Speaker 1: influence our perception of the flavor of foods and beverages.
Speaker 1: I've been involved in proprietary research that showed that changing
Speaker 1: food color can influence taste perception. Broadly speaking, the effect
Speaker 1: of color on food is well known and significant. A
Speaker 1: quick web search found an open access review by Charles
Speaker 1: Spence titled on the psychological impact of food color. Flavor, intensity,
Speaker 1: detection thresholds, and even basic flavor identification can all be
Speaker 1: manipulated with color changes. It is amazing what a little
Speaker 1: food coloring can do. Uh. Yes, Raphael, that is true,
Speaker 1: and so we made general reference in the episode to
Speaker 1: the idea that say, changing the color of the plates
Speaker 1: or cups in which food and beverage are presented can
Speaker 1: affect the perception of the properties of that food or beverage.
Speaker 1: I wanted to highlight a few specifics about the background color,
Speaker 1: in particular because that was the original context youlu talking
Speaker 1: about blue glaze teacup. So how much does the color
Speaker 1: of a cup or a plate affect what you taste
Speaker 1: or or how you consume food? I found a review
Speaker 1: article but the same author you mentioned, Raphael This is
Speaker 1: also by Charles spin Charles Spence is a psychologist at
Speaker 1: Oxford University who studies food perception. UH. This was a
Speaker 1: different review. It was called Background Color and its Impact
Speaker 1: on Food Perception and Behavior, published in Food Quality and
Speaker 1: Preference in the year eighteen and so after reviewing the
Speaker 1: existing research as of this year, Spence writes, UH, this
Speaker 1: year being when it was published. Spence writes that there
Speaker 1: is clear evidence that quote, while people obviously cannot literally
Speaker 1: taste the plate, the color of the plate, bowl, glass, cup, cutlery, pot,
Speaker 1: and package in slash against which a product is seen
Speaker 1: can certainly influence how appealing of food looks, what it
Speaker 1: tastes like, and even how much we end up consuming
Speaker 1: and or serving ourselves. However, that the interesting thing I
Speaker 1: found from reading His conclusions is that background color and
Speaker 1: food perception relationships are not static and linear, they are
Speaker 1: dying amic and complex. So it's not just like, oh,
Speaker 1: food tastes better on a red plate or something like that. Instead,
Speaker 1: Spence writes that one example is a trend of findings
Speaker 1: that desserts taste sweeter when served off of white plates,
Speaker 1: then when served off of black plates. And meanwhile, black
Speaker 1: plates may enhance the experience of savory dishes. And so
Speaker 1: the dynamic aspect is that whether these effects are desirable
Speaker 1: or not may depend on the properties of the food
Speaker 1: itself and the expectations of the diner. So uh, if
Speaker 1: a if a dessert tends to taste sweeter off of
Speaker 1: a white plate, and that dessert is already considered too
Speaker 1: sweet in isolation, it may actually be more enjoyable if
Speaker 1: it's consumed off of a black plate, dulling the sweetness,
Speaker 1: Whereas the opposite holds true as well. A dessert that
Speaker 1: people consider not sweet enough can be enhanced by a
Speaker 1: white plate, heightening the perception of sweetness. And there are
Speaker 1: other interesting findings well that Uspence mentioned and his conclusions.
Speaker 1: One is that when a food is considered an unhealthy indulgence,
Speaker 1: people seem to naturally eat less of it when it
Speaker 1: is presented on a red plate, and the reasons for
Speaker 1: these effects of color on food perception and consumption behavior
Speaker 1: are still up for debate, like do the colors function
Speaker 1: by triggering environmentally salient associations between certain colors and certain
Speaker 1: types of nutrient contents? You know? Could it be that
Speaker 1: when you see this color in the natural environment, it
Speaker 1: often has this kind of uh, maybe a poisoning danger
Speaker 1: associated with it, or this kind of nutrient reward associated
Speaker 1: with it? Or are these associations learned or are they
Speaker 1: simply a result of color effects on mood? And questions
Speaker 1: like that, uh, And I think those are not fully
Speaker 1: solved yet. But anyway, back to Rafhaile's message, however, I
Speaker 1: think you may both have done Plenty wrong. There was
Speaker 1: a bit of chuckling over Plenty. This is our reference
Speaker 1: to Plenty the elder. Uh. There was a bit of
Speaker 1: chuckling over Plenty writing that sappa boiled in copper pots
Speaker 1: tasted bitter, while the same beverage boiled in lead pots
Speaker 1: tasted sweet. At least in this case, Plenty may have
Speaker 1: been accurately reporting a real phenomenon. If his starting grape
Speaker 1: juice had been sitting around long enough to form some
Speaker 1: acetic acid, Plenty may well have been cooking up some
Speaker 1: lead acetate, also known as sugar of lead. Lead acetate
Speaker 1: is a toxic compound with a sweet taste. By the
Speaker 1: same token, dissolved copper has a metallic and bitter taste
Speaker 1: at least according to determination of the taste threshold of
Speaker 1: copper in water by Zacharias. At all the lead pot
Speaker 1: might actually have made the sappa taste sweet, though also poisonous.
Speaker 1: And to come back on this, Yes, Raphael, this is
Speaker 1: a great point to explore for those of you who
Speaker 1: don't know or don't remember the original context of this
Speaker 1: little digression we did some years back. Rob and I
Speaker 1: had an episode where we talked about people intentionally consuming
Speaker 1: lead acetate as a medicine or a food additive, which
Speaker 1: you absolutely should not do. It is highly poisonous. But
Speaker 1: one of the examples we discussed was a passage in
Speaker 1: Plenty of the Elder where he writes that leaden pots
Speaker 1: and not copper pots, should be used for the production
Speaker 1: of sappa. Sappa was a like a sweet syrup used
Speaker 1: by the ancient Romans, I think used kind of in
Speaker 1: the way that you know a bartender might use simple
Speaker 1: syrup today. It was a sweetening agent, though not as
Speaker 1: sweet as today's simple syrup would be, but um, it
Speaker 1: was a It was a sweetening agent to syrup that
Speaker 1: the ancient Romans made by boiling down and reducing a
Speaker 1: liquid called must, which was a type of lightly fermented
Speaker 1: grape juice, kind of a weak wine. And the reasoning
Speaker 1: we discussed in that episode is exactly what Raphael is
Speaker 1: saying here that Plenty's recommendation was probably because boiling must
Speaker 1: in a metal pot would cause some chemical reaction between
Speaker 1: the acetic acid, which is the type of acid that
Speaker 1: is in vinegar, uh and uh, the acetic acid in
Speaker 1: the juice and the metal walls of the pot. So
Speaker 1: if it's copper pot, this is going to result in
Speaker 1: copper acetate salts, which tastes disgusting, bitter, nasty, metallic flavor.
Speaker 1: And uh. If you boil it in a lead pot,
Speaker 1: on the other hand, the same thing happens, but it
Speaker 1: forms lead acetate, which is very poisonous but is also sweet.
Speaker 1: So yes, Raphael, your analysis is spot on. I think
Speaker 1: Plenty's advice about pot metal selection was exactly right from
Speaker 1: a flavor point of view, just without any understanding of
Speaker 1: the dire health effects that could flow from this. Uh
Speaker 1: And to supplement this, I wanted to read from the
Speaker 1: entry on sugar of lead in the Oxford Companion to
Speaker 1: Sugar and Sweets. This entry was written by the American
Speaker 1: chemist Michelle in FRANCEL. Francile Wrights quote. Chemical analysis of
Speaker 1: sappa produced according to the recipes dating from the Ascle
Speaker 1: Roman period using kettles of similar metallic composition as those
Speaker 1: found at Pompeii and other sites, suggests that the lead
Speaker 1: content of sappa was eight hundred and fifty milligrams per leader,
Speaker 1: many thousand times higher than what is generally allowable in
Speaker 1: drinking water, even diluted and used sparingly. Sweetening with sappa
Speaker 1: posed a serious risk. However, to come back on what
Speaker 1: you said, Raphael, about the validity of Plenty's idea that
Speaker 1: that it really did make the sapa sweeter to use
Speaker 1: a lead pot France, Will argues in this entry in
Speaker 1: the Oxford Handbook here that the amount of sugar of
Speaker 1: lead produced by boiling down a pot of must probably
Speaker 1: would not have made a major contribution to the sweetness
Speaker 1: of the syrup, because it would only represent a taste
Speaker 1: change equivalent to adding a pinch of sugar to a
Speaker 1: product that was already pretty sweet. So you know this,
Speaker 1: sappa would already have levels of glucose and fructose equivalent
Speaker 1: to roughly one cup of table sugar per leader of liquid.
Speaker 1: So in the specific example of sappa, the preference for
Speaker 1: lead pots over copper might be more due to the
Speaker 1: fact that lead pots do not produce the disgusting bitter
Speaker 1: copper flavor than to the small amount of additional sweetness
Speaker 1: that the lead would add. And while we're on the subject,
Speaker 1: I just thought I should add that the practice of
Speaker 1: intentionally adding lead to food products was not limited to
Speaker 1: this sweetening effect for sappa. In ancient Rome. Up until
Speaker 1: the nineteenth and twentieth centuries, lead metal and lead salts
Speaker 1: were used in a number of ways. Were used as
Speaker 1: a preservative and an antimicrobial agent, and just got into
Speaker 1: foods because people used lead machinery and cookware to make
Speaker 1: foods with, but it was used as an antimicrobial agent
Speaker 1: and beverages like wine and cider because sugar lead is
Speaker 1: poisonous to bacteria. In the same way it's poisonous to
Speaker 1: us and Francile writes quote Vintner's observed the filtering fermentation
Speaker 1: mixtures through lead sieves or dropping some lead shot into
Speaker 1: bottled wine noticeably reduced spoilage. A firm connection between ingesting
Speaker 1: low levels of lead in these beverages and lead poisoning
Speaker 1: was finally made in the early nineteenth century, in part
Speaker 1: because of the correlation between outbreaks of colic of Potu
Speaker 1: uh and the arrival of wine shipments containing lead. Colic
Speaker 1: of Potu, by the way, is the name for an
Speaker 1: originally mysterious condition also known as Devonshare colic, which was
Speaker 1: observed I believe beginning in the seventeenth century, but it
Speaker 1: affected uh people in France I think, mostly through wine,
Speaker 1: and people in Devonshire, England through their cider. In both
Speaker 1: cases it was eventually determined that lead was the was
Speaker 1: the culprit lead used as a preservative in some cases,
Speaker 1: or because of production processes using lead lined machines. Finally,
Speaker 1: coming back to the end of Raphael's message here file rites. Lastly,
Speaker 1: I have noticed Joe building confidence in understanding rayology and
Speaker 1: fluid dynamics over the years. I don't know about that, Raphael,
Speaker 1: but I appreciate uh. He says, you both did a
Speaker 1: great job making the physics behind the teapot effect more accessible.
Speaker 1: Reyology is one of those areas where the concepts can
Speaker 1: be really hard to understand, but once you do, you
Speaker 1: will see its principles in action everywhere, especially in the kitchen. Also,
Speaker 1: I can confirm that the periodically mentioned on the rayology
Speaker 1: of cats is hilarious to rayologists in equals three sample
Speaker 1: of three. I think thanks for the great show, Rafael. Ps. Unsurprisingly,
Speaker 1: I'm also a fan of Lauren and Annie over at Savor.
Speaker 1: Everyone should go listen to them too. So yes, thank
Speaker 1: you for the message, Rafael, and absolutely people should go
Speaker 1: check out Savor. That is a podcast hosted by our
Speaker 1: friends Lauren Vogelbaum and Annie Reese and it's a wonderful
Speaker 1: home for food nerds everywhere. Again, it is called Savor
Speaker 1: s A v O R. You can find it wherever
Speaker 1: you get your podcasts. Tell him we sent you. Okay,
Speaker 1: This next message about Tea comes from Stephanie. Stephanie says, Hello,
Speaker 1: I was listening to the first episode on t and
Speaker 1: you've got about nine of the way to explaining one
Speaker 1: of my favorite facts about tea. In English, the word
Speaker 1: tea can refer to all sorts of beverages, including those
Speaker 1: made with Camillia senensis, but also herbal teas and other
Speaker 1: usually hot steeped beverages. The French language differentiates between unta
Speaker 1: rhymes with bay made with Camillia senensis and untizan made
Speaker 1: with other plants. The lack of this easy distinction in
Speaker 1: English can definitely cause some confusion. Interestingly, French also differentiates
Speaker 1: between caffeine and teen or I think in English, I've
Speaker 1: heard it pronounced theene, but tayene or theene the caffeine
Speaker 1: found in Camilia senensis in common parlance. At least that
Speaker 1: distinction is made in the Quebec dialect of my husband
Speaker 1: and in laws. I had wrongly assumed that this was
Speaker 1: another example of French being more precise about tea related
Speaker 1: vocabulary than English, and thought there were two different chemicals,
Speaker 1: caffeine and taine. I only realized through listening to your
Speaker 1: episode that they are in fact the same compound, despite
Speaker 1: the different names. I also learned today the English word theene,
Speaker 1: which means the same as the French one, but which
Speaker 1: I had never heard before despite being an avid drinker
Speaker 1: of teas and tissan's. Thanks for always expanding my knowledge
Speaker 1: and my concept of what stuff can be fascinating. Stephanie,
Speaker 1: Thank you, Stephanie. Okay, this next message is from Andreas.
Speaker 1: Andrea said, Dear Robert, Dear Joe, I'm a longtime listener
Speaker 1: and currently very much enjoying your episodes about te I
Speaker 1: write in to tell you a little bit about a
Speaker 1: t tradition in Germany, especially in the region called East Frisia.
Speaker 1: Even though I live around two hours removed from that area,
Speaker 1: several vacations there made me really appreciate the fine drink
Speaker 1: called post freeze and tea. It is a quite strong
Speaker 1: blend of black teas, almost exclusively a psalm tea, and
Speaker 1: it never fails to pick me up on those gray
Speaker 1: and rainy days. There is a special ritual to drink it.
Speaker 1: I copied a text from a German website of one
Speaker 1: of the traditional suppliers of the tea and ran it
Speaker 1: through an Ai translation for you to enjoy. Thanks for
Speaker 1: all the great content. I hope you will do this forever.
Speaker 1: Regards Andreas. Okay, so this is how you make the
Speaker 1: post freeze and tea, at least as mediated through an
Speaker 1: AI translator. It says placed the loose tea leaves in
Speaker 1: a well preheated pot of fresh boiling water so that
Speaker 1: they are covered. Allowed the tea to steep for three
Speaker 1: to five minutes, preferably in a kettle or teapot. Then
Speaker 1: fill the fragrant infusion with the remaining water. It is
Speaker 1: best to pour the finished teeth through a strainer into
Speaker 1: a preheated serving pot and keep it warm on a
Speaker 1: tea warmer. Now comes the pleasure in the cup, as
Speaker 1: East Frisians love it. First, a cluntia, a white sugar candy,
Speaker 1: is placed in the cup. When the hot tea is
Speaker 1: poured over it, the rock candy crackles, creating anticipation and
Speaker 1: giving the tea a fine sweetness as it melts. A
Speaker 1: few drops of fresh, high percentage cream, which is not
Speaker 1: stirred in the East Frisian way, conjures up the famous vulcia,
Speaker 1: the little cloud, which makes the enjoyment of the tea perfect.
Speaker 1: The cream is added to the tea counterclockwise to symbolically
Speaker 1: stop time. That's nice. East Frisian connoisseurs divide the unstirred
Speaker 1: experience in to three phases. The first sip of tea
Speaker 1: with cream is followed by the second sip of tea
Speaker 1: with cream. Something might have been lost in translation there.
Speaker 1: I'm not sure which completes the three tiered pleasure with
Speaker 1: the sweet finish. It offers the courtesy to enjoy at
Speaker 1: least three cups, which is why it is not called
Speaker 1: for nothing. Dree u dree dry dree st uh ost
Speaker 1: Friesian wrecked or three is East Frisian right, It's better
Speaker 1: by a country mile. The small teaspoon is only used
Speaker 1: to signal to the host after the tea has been
Speaker 1: poured into the cup that you do not want any more.
Speaker 1: So thanks for sharing this, Andreas, and I've never heard
Speaker 1: of this before I looked it up. I encourage everyone
Speaker 1: to go look up images of East Friesian tea to
Speaker 1: see the patterns left by the unstirred cream. That seems
Speaker 1: to be the most interesting thing about it, the the
Speaker 1: visual uh flower. Coming back to the how the appearance
Speaker 1: of food affects the flavor, the appearance of the unstirred
Speaker 1: cream dropped into the cup forms mostly beautiful but occasionally
Speaker 1: disgusting shapes, and I only say, disgusting, because there are
Speaker 1: some cases where it looks like maybe it's when there's
Speaker 1: a bit more dribbling of individual drops. To me, this
Speaker 1: has the unfortunate effect of looking like the spots that
Speaker 1: form in a petrie dish when bacterial colonies are blooming,
Speaker 1: especially when the you know, the translucence of the tea
Speaker 1: naturally somewhat resembles an agar plate. But in most cases
Speaker 1: this tea looks lovely. I think it's a nice variation
Speaker 1: on that other beverage art tradition, the designs that people
Speaker 1: make in latte foam. So if latte foam is a
Speaker 1: bit more controlled, a bit more representative, maybe making a
Speaker 1: hard or a cat face or whatever, the East Frisian
Speaker 1: tea is a bit more abstract. It's kind of fractal,
Speaker 1: an emergent, but very cool. Thank you, Andreas. Okay. I
Speaker 1: think we're gonna finish up to day with a message
Speaker 1: about weird House cinema. This one comes from Pat and
Speaker 1: it's in response to our Weird House Cinema episode on
Speaker 1: let Sleeping corpses Lie, which was the nineteen seventy four
Speaker 1: Italian Spanish horror movie about how science is bad and
Speaker 1: if we don't kill Science once and for all, it
Speaker 1: will inevitably raise the dead from their graves with ultrasonic radiation. Uh.
Speaker 1: This movie was a real hoot to cover, and one
Speaker 1: thing we discovered in that episode was this movie has
Speaker 1: a very long list of alternate titles. One was let
Speaker 1: Sleeping corpses Lie, which is okay, but others were things
Speaker 1: like the Living Dead Manchester Morgue, which is strange because
Speaker 1: the movie does not take place at a Manchester morgue,
Speaker 1: though I think some scenes were shot at a Manchester
Speaker 1: adjacent morgue or hospital. Uh. And finally, there was one
Speaker 1: title of the movie which was Don't Open the Window,
Speaker 1: which as far as we could tell, has absolutely nothing
Speaker 1: to do with the film at all. A onto the message,
Speaker 1: Pat says Robert Joe. The last Weird House was a
Speaker 1: good one. I'll have to see this one. You guys
Speaker 1: talked about the strangeness of one of the release titles,
Speaker 1: don't Open the Window. Seems that this phrase is idiomatic
Speaker 1: in Spanish and means quote to bring something to light.
Speaker 1: It seems the title suggests that the enemy Science is
Speaker 1: invoked and leads to horror. Thanks for all the fun, Pat,
Speaker 1: Pat I've never heard that idiom before. I tried to
Speaker 1: kind of look it up and didn't find much. But
Speaker 1: I believe you other Spanish speakers in the audience please
Speaker 1: right in about that. What's the deal with with opening
Speaker 1: the window? Is science opening the window of knowledge? And
Speaker 1: thus according to this movie, uh, you know, don't open
Speaker 1: the window, like don't don't do those experiments. I'm not sure,
Speaker 1: but despite never hearing that one, I do know of
Speaker 1: a a window idiom in Spanish which is tire lacasa
Speaker 1: poor love antana, which basically means uh to well, literally
Speaker 1: it means to throw the house out the window, and
Speaker 1: from what I understand, this means like to go all out,
Speaker 1: as we say in English, to spend a lot of
Speaker 1: money on something, to spare no expense. That's a really
Speaker 1: good one. Okay, I think that does it for the
Speaker 1: mail bag today. Just a reminder that we will be
Speaker 1: running Vault episodes this week and Tuesday of next week
Speaker 1: while Rob and I are out. But I should be
Speaker 1: back with a new Listener mail episode on Monday, and
Speaker 1: then we will have more new episodes for you that week,
Speaker 1: probably on Wednesday, March one. In the meantime, if you're
Speaker 1: new here, this is the Stuff to Blow your Mind podcast.
Speaker 1: Please subscribe wherever you get your podcasts uh we. We
Speaker 1: do different episodes throughout the week. Our core episodes publish
Speaker 1: every Tuesday and Thursday. Those are most often about science
Speaker 1: in one way or another, but we like to jump
Speaker 1: across disciplines. On Monday's we read back listener mail in
Speaker 1: episodes like this one, though usually my co host Robert
Speaker 1: Lamb is here with me. On Wednesdays we do a
Speaker 1: short form scripted episode called The Artifact or the Monster Fact.
Speaker 1: And then on Friday's, when the week is done, it's
Speaker 1: time for Weird House Cinema, which is an episode where
Speaker 1: Rob and I feature and discuss a weird movie. They
Speaker 1: can be good, they can be bad, they can be classic,
Speaker 1: they can be obscure. All movies are fair game as
Speaker 1: long as they are weird. And then, finally, on Saturday's
Speaker 1: we uh we highlight an episode from the vault from
Speaker 1: the olden days uh Big thanks to our audio producer
Speaker 1: J J. Pauseway. If you would like to get in
Speaker 1: touch with us with feedback on this episode or any other,
Speaker 1: to suggest a topic for the future, or just to
Speaker 1: say hello, you can email us at contact at Stuff
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