'Fermentation': When Food Goes Bad But Stays Good.

June 13, 2012

Guests: Sandor Katz – Lynn Shelton

TERRY GROSS, HOST: This is FRESH AIR. I'm Terry Gross. Yogurt, pickles, cheese, sour cream, salami, vinegar, sauerkraut, soy sauce, breads, chocolate, coffee, wine and beer are just a few of the most popular fermented foods and beverages. My guest, Sandor Katz, a self-described fermentation fetishist, has spent nearly two decades exploring the realm of fermentation and learning about the digestive benefits of bacteria present in living fermented foods.

Katz has written a new book called "The Art of Fermentation." It has a forward by Michael Pollan. The book is about the hows and whys of fermentation with advice about how to make fermented foods at home. Katz grew up in Manhattan but now lives in Tennessee, where he has a garden and ferments many of the vegetables he grows. He's taught hundreds of fermentation workshops across America.

Sandor Katz, welcome to FRESH AIR. I think the biggest surprise to me in your book was thinking of fermented foods as probiotic foods. To me, probiotic foods, that's yogurt. I never think of, like, sauerkraut or other fermented foods as being probiotic.

SANDOR KATZ: Well, yogurt is a fermented foods, and, you know, many different types of fermented foods, particularly those fermented by lactic acid bacteria, can be thought of as probiotics.

GROSS: So what other foods does that include?

KATZ: Well, fermented vegetables, not only yogurt but kefir and many other types of fermented dairy products and, you know, a large group of beverages might be kombucha, but there's kavas, there's mauby, there's tepache.

GROSS: I have no idea what you're talking about.

(LAUGHTER)

KATZ: Well, I'm giving you names of beverages that people around the world drink. I mean these lightly fermented beverages, you know, of which, you know, kombucha has burst upon the American scene, you know, are popular in the places that they come from. And so this is a pattern of fermentation seen around the world, these lightly fermented beverages that contain live lactic acid bacteria, which really are very beneficial and stimulating for human beings.

GROSS: So getting back to the probiotic qualities, the good-guy bacteria qualities of fermented foods, something like sauerkraut, I've always thought of that as being kind of vinegary and acidic and therefore not great for my digestive system, but are you saying that it has probiotic qualities?

KATZ: Yeah, sure. I mean, sauerkraut does not have vinegar in it, at all. Vinegar is an acid that is acetic acid. The acid in sauerkraut is lactic acid, and this is the same acid that's found in yogurt. And, you know, almost all of the probiotic foods are probiotic by virtue of the presence of lactic acid bacteria, and they produce as their metabolic byproduct lactic acid. So that's, you know, a characteristic of, you know, almost all probiotic foods.

GROSS: So while we're on the subject, you recommend eating fermented foods, you know, on a regular basis but not a lot at a time.

KATZ: Yeah, in general these foods have been used as condiments, as embellishments of food. And, you know, every spoonful has billions of bacteria, and it's not really a matter of eating huge quantities of it. It's a matter of eating them pretty regularly. And really what's probiotic about these foods, you know, is that the lactic acid bacteria in them can help to replenish and diversify the populations in our gut, which due to a number of chemical factors in our contemporary lives, including antibiotic drugs, antibacterial cleansing products, chlorine in water, are subjected to more or less constant attack.

So for us in the 21st century, more than for people in the past, we need to consciously thinking about replenishing and diversifying these populations.

GROSS: And just briefly, what do the good-guy bacteria do in your gut?

KATZ: Well, bacteria in our gut enable us to live. You know, we could not survive without bacteria. We've all grown up, you know, indoctrinated by what I call the war on bacteria and this idea that bacteria in general are dangerous and bad for us, and our lives would somehow be better or safer if we could, you know, eradicate them.

But, you know, in fact we could not live without bacteria. They enable us to digest food, they enable us to assimilate the nutrients in our food, and they play a huge role, just beginning to be understood, in our immune functioning and in many other regulatory processes in our bodies.

I mean, remember, all life has evolved from bacteria, and no other form of life has lived without bacteria. So our bacteria perform all sorts of essential functions for us, and because we are continually attacking them effectively with, you know, all of these chemicals in our lives, you know, we simply, you know, replenishing and diversifying these populations has a benefit for us.

GROSS: I love the way you describe fermentation as a flavorful space between fresh and rotten.

(LAUGHTER)

GROSS: Do you want to describe what you mean?

KATZ: Sure. I mean, I think that one of the most, you know, basic lessons that we learn as, you know, small children from our parents is, you know, what is appropriate to put in our mouths. We reject certain food because it is rotten. You know, certain food we can see is fresh.

But there is this creative space between fresh food and rotten food where, you know, most of human culture's, you know, most prized, you know, delicacies and culinary achievements exist in this space. If you walk into a gourmet food store and start thinking about the nature of the foods that we, you know, elevate on the gourmet pedestal, almost all of them are the products of fermentation.

Fermentation creates strong flavors. They're not always flavors that everybody can agree on. I think cheese illustrates this really well. So, you know, around the world you find these iconic foods produced by fermentation that create strong, strong flavors that become really markers of cultural identity, and in many cases people who have not been raised within the culture, you know, find these foods, you know, very challenging.

GROSS: So what are the fermented foods that are part of your cultural identity?

KATZ: Well, growing up in New York City, one of my very favorite foods were sour pickles, what some people might know as kosher dills, and these are pickles that are made without any vinegar, simply in a brine, and the acidification comes from fermentation.

And I feel like I was just imprinted with this flavor of lactic acid from a very young age. You know, this was just a flavor that I really, really loved.

GROSS: So tell us how the kind of pickle you love is made.

KATZ: To ferment sour pickles, you take small cucumbers, and you mix up a brine, which is simply salty water. The strength of the brine has implications, you know, usually a 5 percent brine, which means in relation to the weight of the water, 5 percent salt, and usually I'll add grape leaves as a means of helping to keep the cucumbers crunchier longer.

And then lots of dill and lots of garlic, and then it's just a matter of waiting, you know, from a couple of days to a couple of weeks, depending on the temperature. The metabolism of all of these fermenting organisms speeds up in warmer weather. So in summer heat, which is when cucumbers tend to be ripe, the process goes faster. So it might be as few as, you know, three or four days.

In more moderate temperatures, or if you have a cellar, it could be a couple of weeks.

GROSS: So you just let it sit out, or do you have to put in an incubator?

KATZ: No incubator, just at room temperatures and actually the cooler the better. You know, a cellar is really best if you're looking to preserve sour pickles for any length of time, but you can really do it at any ambient temperatures, as long as you understand that it'll go faster when the temperatures are warmer.

Because the cucumbers will have a tendency to float to the surface, where they can be exposed to oxygen, which can promote the growth of yeasts and molds, I'll usually place a plate on them to keep them weighted down below the surface of the water.

GROSS: One of the reasons for fermenting food is that it lasts longer. Like, pickles will last longer than cucumbers will if just left out. In fact, like, when you buy a pickle, it's usually in a pickle barrel. It's just, like, not sitting in a refrigerator, it's just sitting in a pickle barrel. How long will it last?

KATZ: Well, fermentation is really the classic means of preserving, especially in relation to vegetables, but in relation to many other types of foods, as well. And, I mean, actually I am nearing the bottom of a barrel of radish kraut that I made at the beginning of November. So that has just passed its seven-month mark, not in any refrigeration, just in a cellar, and it is wonderful.

You know, it really - once it reaches a certain stage of acidity in a cool environment and in a salty environment, it pretty much plateaus, and for a very long time, you can eat it. It's not forever. It's not the way we think of, you know, canned foods that you can put into a pantry or storm cellar and forget about for 10 years and still eat. I mean, these foods are alive, they're dynamic, but they're extremely effective strategies for preserving food through a few seasons, which is really the point.

I mean, you're taking your harvest at the beginning of the season, when you won't have fresh vegetables, and you're preserving it through the season where there are no fresh vegetables, and it's easy to make it last, you know, until there are fresh vegetables again.

GROSS: If you're just joining us, my guest is Sandor Katz. He's the author of the new book "The Art of Fermentation." And we'll talk more about fermentation after we take a short break. This is FRESH AIR.

(SOUNDBITE OF MUSIC)

GROSS: If you're just joining us, my guest is Sandor Katz. He's the author of the new book "The Art of Fermentation." So you suggest that if you want to start making fermented foods that a good place to start is sauerkraut because it's really easy. What's your recipe for making sauerkraut?

KATZ: Well, sauerkraut is incredibly easy to make. It's fast, you don't need any special equipment, you don't need any special cultures, and it is intrinsically safe. So you take a cabbage or a combination of vegetables or really any vegetable you want, and the first thing is to create surface area. So you chop the vegetables or grate the vegetables, and then in a large bowl, lightly salt them. There's no magic number for how much salt to use.

Most of the commercial manufacturers who I've encountered work with somewhere around 1.5 percent salt. I never measure the salt. I just try to...

GROSS: What does the salt do?

KATZ: The salt pulls water out of the vegetables. The salt actually crisps up the vegetables a little bit because salt has the quality of hardening pectins. And it also - all ferments are a matter of creating a selective environment that favors certain types of organisms while discouraging other types of organisms. And lactic acid bacteria, what we're trying to cultivate in the production of sauerkraut, are very salt tolerant, while certain other bacteria that might also be present cannot tolerate salt.

And it also slows down the whole process, which really helps in terms of preservation.

GROSS: So after you shred the cabbage or whatever it is that you're fermenting, whatever vegetable it is, you have to kind of like pound it a little bit to release the juices, and what does that do?

KATZ: So you can pound it with a tool. What I usually do at a small scale is just use my clean hands and squeeze the vegetables for a couple of minutes. And what this does is it bruises the vegetables, it breaks down cell walls and basically enables the cells to give up their juices, which facilitates our being able to submerge the vegetables under liquid, which really is the point.

We're trying to protect it from the air by submerging the vegetables under liquid. And then stuff it into a jar. You want to press really hard to force out any air bubbles, and you want to make sure that the vegetables are pressed down under their juices. And then just seal the jar.

But be aware that pressure will be produced. So you don't want to leave it sealed for days and days. I like to leave it on the counter, and each morning while I'm making my tea, I just open it and release the pressure. And then after a couple of days, you can really start enjoying it.

I mean, the flavors transform very quickly. The bacteria proliferate. The texture changes, and what I recommend to people experimenting for the first time, is to just taste it at periodic intervals. You know, taste some after two days. Taste some after four days. Taste some after a week. And then you can get a sense of whether you're liking it more and more as the flavor gets more acidic or whether it's acidic enough, and you want to move it into your fermentation-slowing device, which is your refrigerator.

GROSS: So you're adding water, or you're just using the juices of the vegetable?

KATZ: I hardly ever add water. You get a much more concentrated flavor if you can just get the juices out of the vegetables. You know, if for whatever reason you can't squeeze the vegetables, if you're using very old vegetables that have sat in a warehouse, often they have, you know, evaporated some of their juices. So sometimes it's not possible, but almost always it's possible to get the juices out of the vegetables, and you'll get a much more concentrated flavor if you don't add any water.

GROSS: But you can add water if you need to?

KATZ: Yeah, and also, you know, like I described sour pickles. If you want to leave a vegetable whole or in large chunks, then it's impossible to pull the water out of the vegetables. So that's when you mix up a brine. But typically in sour pickles or other brined vegetables, you know, when you have it floating in a bunch of salt water that you're adding to it, you add lots of spices to sort of compensate for that dilution of flavor.

And you can certainly flavor this with any kind of spices. I mean, in the German sauerkraut tradition, often people used juniper berries or caraway seeds. In Russian traditions, often they'll at a little bit of fruit like cranberries or apples. In the Korean kimchi tradition, it's usually hot pepper and ginger and garlic and onions. But really you could experiment with, you know, any kind of seasonings that you like to spice it up.

GROSS: Since we're dealing with bacteria here and hopefully with the correct bacteria, if you make any kind of fermented vegetable yourself, and you eat it, what are the odds you're going to make yourself sick because it grew the wrong kind of bacteria?

KATZ: Well, according to the U.S. government, there has never been a single case of food poisoning in the United States from fermented vegetables. I mean, this food is about as safe as it gets. You couldn't say that about raw vegetables. I mean, all the time we hear about people getting sick from, you know, lettuce, spinach, tomatoes or, you know, other raw vegetables.

And, you know, the point with sauerkraut is that, you know, even if your vegetables had been subjected to some sort of incidental contamination, the indigenous populations of lactic acid bacteria, you know, are so great that, you know, once you create an environment that's hospitable for them, they easily dominate, you know, any kind of incidental contaminant that might also be present.

And then the acidification basically would destroy any pathogenic bacteria. You know, none of the pathogenic bacteria that we hear about or worry about can survive in an acidic environment. So this is actually a process that makes food safer, as well as preserves it.

GROSS: Let's talk about yogurt, which is, you know, one of the most popular fermented foods. What's the principle behind yogurt?

KATZ: The principle behind yogurt is almost the same as the principle behind sauerkraut. We are using lactic acid bacteria to preserve food. The method for it is somewhat different. There are many different types of lactic acid bacteria.

And the ones that are used in most yogurt traditions are bacteria that we would describe as thermophilic, meaning that they are most active in an elevated temperature range. So usually when you make yogurt, you want to incubate the yogurt by creating an environment that stays between 110 degrees and 115 degrees Fahrenheit.

GROSS: Do you need a starter to introduce the right bacteria to the milk that you're making the yogurt from?

KATZ: Yes, absolutely. Yogurt is the classic example of what is often called a cultured food. And the cultures are - is the community of bacteria that you're introducing, and the act of introducing it is called culturing the food. So yes, to make yogurt you always need basically a batch of mature yogurt, and that's what you introduce is just a little spoonful of mature yogurt into the fresh milk that you want to turn into yogurt.

GROSS: And then what?

KATZ: Well, OK, first what you do is you take your milk, and you heat it up. I usually heat it to about 180 degrees and then cool it down to about 115 degrees and introduce my starter culture. And then for an incubation space, usually what I do is I take an insulated cooler, and I preheat it with hot water. So it's preheating while I'm heating up the milk and cooling down the milk.

And so if I get that insulated chamber to be in the 110- to 115-degree range, then I just take my milk that I have cultured with the yogurt starter and put it into that 110- to 115-degree chamber and leave it there for somewhere between four to eight hours. And when I take the jars of milk out, they have solidified into yogurt.

GROSS: So what's the difference between curdled milk and yogurt?

KATZ: Well, OK, let me talk a little bit about milk and drinking milk. You know, the milk that we grew up with, you need a refrigerator for that. Fresh milk is really a phenomenon of the 20th century in regions of the world where refrigeration became widespread.

The milk that most people in the world have historically enjoyed and that, you know, many people in the world continue to enjoy are sour forms of milk. Yogurt could be considered a sour form of milk. Kefir could be considered a sour form of milk.

But we have a word in the English language - clabbering. Clabbered milk, and clabbered milk is essentially raw milk that is allowed to sit at ambient temperatures. And after, you know, approximately 24 hours, you know, give or take, depending upon the temperatures, that milk begins to thicken. And when it begins to thicken, you know, then we call that clabbered milk.

But the flavors of clabbered milk will be very, very different with different milks in different environments and different seasons and different temperature ranges. And so, you know, when people have a flavor in their clabbered milk that they especially like, they seek to perpetuate it by adding a little bit of that batch that they really liked into the next batch.

And this is really the story of fermented milk products all around the world. And, you know, yogurt is just the one that became, you know, the global superstar that's, you know, sold in every supermarket.

GROSS: Sandor Katz is the author of "The Art of Fermentation." In part two of our discussion, which we'll hear another day, he'll talk about cheese, meat, beer and wine. I'm Terry Gross, and this is FRESH AIR.

TERRY GROSS, HOST: This is FRESH AIR. I'm Terry Gross. My guess, screenwriter and director Lynn Shelton, first became known for her Indie film, "Humpday," about two straight men who decide to make a gay porn film and submit it to an annual Indie porn festival.

"Humpday" led to her directing an episode of "Mad Men." Her new film, "Your Sister's Sister," like "Humpday," relies on a lot of improvisation from the actors. Mark Duplass, who plays Jack in the new film, also starred in "Humpday." Duplass and his brother, Jay Duplass, also direct films that rely on improvisation.

"Your Sister's Sister" begins a year after the death of Jack's brother. He's not taking it well, so his good friend, Iris, played by Emily Blunt, tells him to go to her father's cabin in the woods and spend some time getting himself together, but he doesn't find the solitude she promised. Her beautiful half-sister, Hannah, played by Rosemarie DeWitt, is there and then Blunt comes to visit and the relationships get very complicated.

In this scene, Iris and Hannah are telling Jack how their father had been involved in multiple romantic relationships over the years.

(SOUNDBITE OF MOVIE, "YOUR SISTER'S SISTER")

EMILY BLUNT: (as Iris) OK. He was with her mom for 10 years. Had an affair with my mom, who was his secretary.

ROSEMARIE DEWITT: (as Hannah) Got your mom, Lenore(ph), pregnant.

BLUNT: (as Iris) Yes.

DEWITT: (as Hannah) Married her.

BLUNT: (as Iris) Moved to London.

DEWITT: (as Hannah) Moved to London.

BLUNT: (as Iris) Got bored of Lenore and then he moved on and then he kind of philandered around for, like, seven years.

DEWITT: (as Hannah) He went through his crazy Warren Beatty phase. The funny thing, though, about those years when he was so bad with the ladies - he was so good with us because that was...

BLUNT: (as Iris) He wasn't.

DEWITT: (as Hannah) No. But that was, like, six summers that it was just the three of us here.

BLUNT: (as Iris) I know, but you were OK with it. I had no respect for that. He just went - he dodged from one to the other and it was gross.

MARK DUPLASS: (as Jack) That's so crazy. So he would just, like, date all of these women, like, for short periods of time with not a lot of emotional investment and...

BLUNT: (as Iris) Yeah, it was horrible.

DUPLASS: (as Jack) ...they were very similar and then he would just move on?

BLUNT: (as Iris) Yeah.

DUPLASS: (as Jack) God, that's just weird. Who does that? Oh, and the patterns emerge.

BLUNT: (as Iris) What are you doing?

DUPLASS: (as Jack) I'm sorry. Skinny jeans George. Skinny jeans Harry. Skinny jeans Vinnie. Vinnie lasted for at least two weeks. He was one of the longer ones.

BLUNT: (as Iris) I don't like dating. You know that. I don't like dating. I don't like dating.

DUPLASS: (as Jack) No. Technic - I think, technically...

BLUNT: (as Iris) I don't like it.

DUPLASS: (as Jack) ...this is...

BLUNT: (as Iris) I get bored. I don't like it.

GROSS: That's a scene from "Your Sister's Sister." Lynn Shelton, welcome to FRESH AIR. So the scene that we just heard explains the relationship between the two sisters. They have the same father. One of the sisters grew up in America, the other in England. Did you write that England-America thing because you wanted to cast Emily Blunt, who's British?

LYNN SHELTON: Originally, the two sisters were both British. They were always going to be half-sisters, but Rosemarie DeWitt came in and saved our production by replacing an actress that we lost three days before the shoot started, believe it or not. And so it was a really - because they were always meant to be half-sisters with two different moms and one dad - this sharing a dad - it was actually a really easy adjustment to make her American and Emily remain British.

So - yeah. It's funny. And, in a way, I think it's almost better because you're wondering from the very beginning, why do they have different accents if they're sisters?

GROSS: I was wondering. Yeah.

SHELTON: And your ears are sort of pricked up waiting for the explanation and then, by the time it comes, you're kind of really listening and you're like, oh, I see. I see. I see. So they only spent summers together and they have this sort of age difference and you're ready to hear all that exposition and kind of get it.

GROSS: How did Rosemarie DeWitt end up being the actress to save the day?

SHELTON: We had, again, a very limited amount of time to find a replacement, so I started running down the list in my mind and, as soon as I thought of Rose, she leapt to the top of my, you know, wish list. And I mentioned her name to Mark Duplass and he said, if she's available, she'll do it. It was a pretty confident statement, but about a year before, they had been in an airport on their way to New Orleans, each to work on a different movie, and she had accosted him at the airport and said, I never do this, but I saw "Humpday" - which is a movie that Mark and I had done together previously - and I really, really loved it and you were great in it. And, you know, she was a fan and she was, more importantly, versed in the kind of work, you know, that I do and...

GROSS: I'm going to stop you right there.

SHELTON: ...so that was really helpful.

GROSS: How would you describe the kind of work that you do?

SHELTON: I incorporate input from the actors - an enormous amount of input from the actors. They participated - the original actors all participated for eight or nine months in the development process and I would ask for their input about who these characters were, what was their back story.

By the time we get to set, we have an enormous amount of back story so that they really know who they are. When they open their mouths to say something, it's going to be like second nature what comes out. And then, on set, I'm asking them to actually write dialog because, you know, I had 70 pages of dialog written out in this case and I asked them not to memorize the lines, just to glance over those scenes and really get a sense of the shape, the content, the emotional trajectory that needs to, you know, take place.

But then to find their way, you know, through each beat of the scene. Again, I'm - what I'm looking for is naturalism, an extreme level of naturalism to the degree that, you know, it almost feels like a documentary, you know, that it just feels like real flesh and blood people having real conversations onscreen.

And I have found that incorporating improvisation to a certain degree really, really helps in that quest.

GROSS: Now, here's the thing. It seems to me, it really helps in getting a kind of naturalistic feel at the same time - and I don't know what I'm talking about here - but it seems to me like, if you're an actor and you have the lines written for you, those words help you embody the character because that character isn't you and that character speaks different from you. And the writer has imagined how that character would speak and, by speaking those words in the way that the writer has imagined it, you become that character.

But, if you're finding your own words for that character, it means that that character is going to be more like you because you're more likely to play it like yourself with the words that you would speak.

SHELTON: It's true. I'm really looking for the overlap. You know, where does the character, which is distinct from the actor as a person, but where does the character overlap?

Mark and Emily and Rose are very distinct from the characters that they're playing. You know, I would not say that they share all of the traits or all of the personality that these characters have, but it's really about finding the connection between yourself and the character and this is what actors do all the time. It's just that, in this case, I'm asking for, you know, you to provide the actual speech.

For instance, there's a scene early on in the film where we're getting to know Iris and Jack, played by Emily Blunt and Mark Duplass, and what their relationship is, which is a relationship of best friendship. And it's the second scene in the film, so it's really early on and we're sort of establishing this report that they have.

There are certain turns of phrase and certain - the way that they tease each other and the way that they sort of push each other in a gentle, loving way. They are able to draw on the friendship that had been established between Mark and Emily over the course of the shoot because it was the last thing we shot in the production schedule. And they were able to pull that report into this relationship.

GROSS: So why don't we hear that scene? And this is an excerpt of Lynn Shelton's new film, "Your Sister's Sister."

(SOUNDBITE OF MOVIE, "YOUR SISTER'S SISTER")

BLUNT: (as Iris) I've been watching you for a year now and whatever you're doing and whatever you think is helping you, I have a responsibility as your friend to tell you that it's not.

DUPLASS: (as Jack) I knew this was coming, by the way.

BLUNT: (as Iris) OK.

DUPLASS: (as Jack) Just tell me what to do.

BLUNT: (as Iris) OK.

DUPLASS: (as Jack) That's basically where I'm at.

BLUNT: (as Iris) OK.

DUPLASS: (as Jack) Just tell me what...

BLUNT: (as Iris) All right.

DUPLASS: (as Jack) You know better than I do. You know I'm...

BLUNT: (as Iris) I have a plan.

DUPLASS: (as Jack) You have a plan?

BLUNT: (as Iris) I just want you to hear me out. It's just a plan right now.

DUPLASS: (as Jack) I love your plans.

BLUNT: (as Iris) You might not love this one, but just hear me out.

DUPLASS: (as Jack) But I don't have any plans.

BLUNT: (as Iris) That's good news. You know that nice red bicycle that you have?

DUPLASS: (as Jack) Yes.

(SOUNDBITE OF BURP)

BLUNT: (as Iris) Yikes.

DUPLASS: (as Jack) Sorry.

BLUNT: (as Iris) What you're going to do...

(LAUGHTER)

BLUNT: You're going to dust off Old Red. You're going to wheel him out of the shed and you're going to get on a ferry. I'm sending you to my dad's place. You know, my dad's place on the island - it's beautiful in the winter. It's idyllic and crisp and peaceful and...

DUPLASS: (as Jack) Like, by beautiful, you mean rainy and cold.

BLUNT: (as Iris) I'm sorry. I got so distracted because all I heard was pissing and moaning.

DUPLASS: (as Jack) Right. Sorry. I started pissing. I'm not pissing. I'm not pissing and moaning. I'm done. I'm done.

GROSS: That was Mark Duplass and Emily Blunt in a scene from "Your Sister's Sister," which was written and directed by my guest, Lynn Shelton. Let's take a short break here, then we'll talk some more. This is FRESH AIR.

(SOUNDBITE OF MUSIC)

GROSS: If you're just joining us, my guest is screenwriter and director, Lynn Shelton. Her new movie is called "Your Sister's Sister" and it stars Mark Duplass, Emily Blunt and Rosemarie DeWitt.

Now, your previous film, "Humpday," starts off with a married couple and they're surprised when the husband's old buddy shows up unannounced at the door after being on the road and so they were living opposite kind of lives. There's like the husband, who's settled down, and the friend who's been on the road.

They go off to this party - the two men - and where the subject ends up being this, like, independent porn film festival known as the Hump Film Festival and they decide to make a gay porn film together and star in it, though neither of them is gay. What an odd idea for a movie. How did you come up with that premise?

(LAUGHTER)

SHELTON: Sometimes, the best stories can come out of just the simple premise of putting characters into a situation that's out of their comfort zone and I came up with this crazy notion of two straight guys daring each other to do something that was completely beyond their ken and totally uncomfortable for both of them.

There really is a festival in Seattle and it's called Hump and it was founded a few years ago by Dan Savage and the idea is to sort of reclaim - it really is this idea of having fun with your sexuality and, you know, being an exhibitionist just for a night, you know, and instead of this sort of mainstream porn industry, like actually celebrating sexuality onscreen in a more personal and interesting - maybe artistic and maybe comedic way.

And I had a friend who went to the festival and saw gay porn for the first time. He'd never seen it before and he was really fascinated by it and I thought his response, as a straight guy, to this gay porn was really interesting. And that was where the wheels started turning for me. I thought, well, what - this interest - this relationship between straight men and gayness, in general, is, I think, really rich territory.

GROSS: So, you know, I've been reading about you and you were quoted as saying - which may or may not be true - but you were quoted as saying that you would describe yourself as a shy bisexual who has crushes on gay men. And I'm going to ask you about this because, you know, "Humpday" and "Your Sister's Sister" involves sexual orientation.

SHELTON: Um-hmm. Yeah. No. I mean, I don't remember saying shy bisexual. Maybe I did say that and I'm just blotting it out. I mean, I'm married, you know, so I'm in a straight relationship and have been for decades, for a really long time. So it's not like I'm an active bisexual, but I've fallen for all stripes of human beings in this world, you know, and I've fallen for straight men. I've fallen for gay men. I've fallen for straight women and gay women. I really have, you know, had crushes on just every single kind of person in the world.

And so, you know, there was this period of time in my life when I had this sort of romantic idea that everybody was like that, you know, that we're all human beings and that a person is a person and if there weren't these sort of societal ideas about gender and sexual orientation that, you know, anybody could fall in love with anybody.

And it was really, you know - making "Humpday" was the experience that really showed me that is so not true. You know, that some people really, truly are straight. You know, there is a spectrum and that there are people who are really at one or the other, you know, and I was - one of the things that was most moving to me after "Humpday" came out was a friend said that her dad, who had been really on the fence about gay rights, saw "Humpday" and really was convinced that gay people should have all the same civil rights as straight people because he could really - it really hit home for him that you are who you are. You are born how you're born and that - here are these two straight guys who really, just for a couple of hours, wanted to not be straight and they couldn't, you know, do it.

GROSS: If you're just joining us, my guest is Lynn Shelton. She wrote and directed the new film, "Your Sister's Sister," which stars Mark Duplass, Emily Blunt and Rosemarie DeWitt. She also wrote and directed the comedy, "Humpday" and she shot an episode of "Mad Men." Not just any episode. This is a pretty famous episode.

So much happened in this episode back in 2010 in season four. Among the things that happened is Joanie told Roger that she was pregnant with his child. She went to have an abortion and, at the end of the episode, we don't know if she goes through with it or not. The ad agency had gotten a new client, which was a defense department company and doing ads for them required getting a security clearance, so Don Draper was being investigated for a security clearance and he was sure his cover would be blown, that the defense department or FBI, whoever was investigating would find out who he really was and he'd be in jail.

And, at the very end of the episode, Megan, his new secretary, has kind of not even bothered to tell him about this because she doesn't understand the significance of this investigation, and Megan, who now is Don's wife - and then, with his new secretary, kind of bungles it, apologizes. At the end of the episode, she asks if she can leave now and go home and she's putting on some lipstick before leaving the office and Don looks at her like he's seeing her for the first time and he's seeing for the first time how beautiful she is and how interesting she is. And who knew back in 2010 that that character would end up becoming his wife? Did you know? You directed that episode. Did you know?

SHELTON: No. No. No, I had no idea.

(LAUGHTER)

SHELTON: No. It was such an incredible privilege to work on that show. I was an enormous, an enormous fan.

GROSS: How did you get to shoot a "Mad Men" episode?

SHELTON: Well, I, you know, yeah. It was great. I had been trying to get TV work. I was trying to break into episodic directing work, because I am a big admirer of a lot of television. I think there's some incredible quality on television right now, and "Mad Men" was at the top of my list.

I mean, I really felt like it was kind of pie-in-the-sky to try to get onto a show of that caliber, but Scott Hornbacher, one of the producers, somehow saw "Humpday." And so I had a great meeting with him, and he said, you know, I'm going to try and get Matthew to see it, but it's going to be hard, because he's incredibly busy.

And then a few, gosh, a month and a half later or something, I got the call that Matt was interested in meeting with me. And, I mean, just the meeting - I remember I had an hour and a half with him in his office, and I thought even if nothing comes of this, I will remember this forever, you know, just getting to sit and talk to Mr. Weiner in his office for an hour and a half.

GROSS: So you didn't know that Megan and Don were going to get married, and that happened further down the line.

SHELTON: Right.

GROSS: But you knew pretty soon whether, you know, maybe in the next episode - maybe not. I can't remember when it was revealed - whether Joan had the abortion or not. Did you know when you were shooting the episode whether she was going to go through with it or not? Or were you left hanging?

And were you supposed to know in order to get whatever nuance was supposed to be about what was going through her mind? Did you need to know what was going through her mind to really shoot it right?

SHELTON: It was a huge, huge secret, and so he let me know, and I think he told Christina at the very last minute, as well. And so she, I believe...

GROSS: Christina Hendricks, who plays Joan.

SHELTON: Who plays Joan. Yeah. I believe we were the only two people on the set who knew. Because he realized that we really needed to know that for the scene on the bus. There's this bus where she's coming back into town, and she's staring out the window, and it's very ambiguous. You know, we don't know if she's sad or if she's sort of, like, thinking about this experience she's just had, or if, you know, what it is. It's open-ended.

GROSS: How do you think knowing that affected the way you shot that scene?

SHELTON: Well, it was such a simple scene. The bus scene, in particular, it was very, very simple and elegant. You know, it was just a very romantic shot, basically. I mean, we had a couple different frames of view of it, but it was just her staring out the window and - lost in thought. And so it was something that was very subtle.

You know, we just got a lot of variation, but it was a very nuanced variation on the expression on her face and, you know, how her eyes looked. And, you know, just - yeah. It was very subtle.

GROSS: Well, Lynn Shelton, thank you so much for talking with us.

SHELTON: Oh, thanks for having me, Terry. It's such a privilege.

GROSS: Lynn Shelton directed the new film "Your Sister's Sister." Coming up, Ed Ward profiles Bobby Charles, one of those rock n' roll figures whose work you're almost certainly familiar with, even though you've probably never heard of him. This is FRESH AIR.

TERRY GROSS, HOST: Bobby Charles was one of those rock n' roll figures whose work you're almost certainly familiar with, even though you've probably never heard of him. He lived in isolation, recorded very little, never performed, and died in 2010. Rock historian Ed Ward tells us about the memorable body of work he left behind.

(SOUNDBITE OF SONG, "WHY ARE PEOPLE LIKE THAT?")

BOBBY CHARLES: (Singing) They'll take your love and your money. They'll take your sugar and your honey. They'll take you skinny or fat. Why are people like that? They'll take your child and your home.

ED WARD, BYLINE: When he was around 13, Robert Charles Guidry began singing with a band around his home town of Abbeville, Louisiana, deep in the Cajun swamps. The band played Cajun music and country music, and, after he passed through town and played a show, Fats Domino's music. It was a life-changing experience for the young man, and he found himself with a new ambition: to write a song for Fats.

One night as he left a gig, he said to his friends: See ya later, alligator. And one of them yelled back: in a while, crocodile. Bobby stopped in his tracks. What did you say? he asked. The friend repeated it. At that moment, as would happen countless times in the future, the song came to him, fully formed.

(SOUNDBITE OF SONG, "SEE YOU LATER, ALLIGATOR")

CHARLES: (Singing) Well, I saw my baby walking with another man today. Well, I saw my baby walking with another man today. When I asked her what's the matter, this is what I heard her say: See you later, alligator. After a while, crocodile. See you later, alligator. After a while, crocodile. Can't you see you're in my way now? Don't you know you cramp my style? When I thought of what she told me...

WARD: Fats didn't want the song, and he told the young man he didn't want to sing about alligators. Somehow, though, the kid wound up singing the song over the phone to Leonard Chess, whose Chess Records in Chicago was the hottest blues label in town. Chess didn't hesitate. He sent the kid a ticket, and when Bobby showed up at his office, Chess said something I can't say on the air. The sentence ended with the word "white" and a question mark, though.

Chess recorded him and put the song out, changing Guidry's name to Bobby Charles, and almost immediately Bill Haley grabbed it for himself. Haley's record was one of the best sellers of 1956, and both Chess and Bobby made some decent money from it. Bobby recorded for Chess until 1958, but his records only sold locally. Along the way, though, he seemed to have pioneered a genre called swamp pop.

(SOUNDBITE OF SONG, "AIN'T GOT NO HOME")

CHARLES: (Singing) Ain't got no home. Ain't got no place to go. Since my baby been gone, things ain't the same no more. She used to hold my hand.

WARD: He also got to realize a dream. One evening, Fats Domino played Abbeville, and Fats invited Bobby to a show in New Orleans. Bobby said he had no way to get there. Well, the fat man said, you'd better start walking. And sure enough, a song popped into Bobby's head.

(SOUNDBITE OF SONG, "WALKING TO NEW ORLEANS")

FATS DOMINO: (Singing) This time, I'm walking to New Orleans. I'm walking to New Orleans. I'm going to need to parachute when I get through walking these blues when I get back to New Orleans.

WARD: Bobby signed with Imperial, Fats' label, but again, nothing hit. He admitted freely that he was part of the problem. He didn't enjoy touring, and he had a jealous wife who didn't like him leaving town. He continued writing and selling songs, and recorded for some local Louisiana labels.

He and his wife parted company, and then, in 1971, he got busted for pot in Nashville. Rather than risk jail, he disappeared. He wound up in Upstate New York, and saw the name Woodstock on a map. He'd never even heard of the famous festival, but the name appealed to him.

Arriving in town, he asked a real estate agent about a place to rent, and wound up in a house shared with two other musicians. They introduced him around, and Albert Grossman - who'd managed Bob Dylan, Janis Joplin, and many others - got interested. The next thing he knew, Bobby was back in the studio with members of The Band, Dr. John and lots of other Woodstock musicians. The resulting album had some truly memorable moments.

(SOUNDBITE OF SONG, "SMALL TOWN TALK")

CHARLES: (Singing) It's all small town talk. You know how people are. They can't stand to see someone else doing what they like to. It's all small town talk. You mustn't pay no mind. Don't believe a word. They'll try to do it every time. You can't believe everything you hear, and only half of what you see. And if you're going to believe in anyone, you've got to believe in me. It's all small town talk.

WARD: It didn't sell, though. Bobby focused on songwriting, but he wasn't comfortable in Woodstock, and in the end, he went back to Abbeville, where he disappeared from public view for an entire decade. He had a good income from his songs, but a run of bad luck: His house burned down, and then his next house blew away in a hurricane.

He kept writing songs, and he entertained visitors who came to Abbeville to meet him, people like Bob Dylan and Neil Young and Willie Nelson. His record label, Rice 'N' Gravy, put out several homemade albums which mixed his old and new songs.

(SOUNDBITE OF SONG, "(I DON'T KNOW WHY I LOVE YOU) BUT I DO")

CHARLES: (Singing) I don't know why I love you, but I do. I don't know why I cry so, but I do. I only know I'm lonely, and that I want you only. I don't know why I love you, but I do.

WARD: At the age of 70, Bobby Charles was diagnosed with cancer, and he died in January, 2010, unknown to most of the world he'd enriched with his songs.

GROSS: Ed Ward lives and writes in France. You can download podcasts of our show on our website freshair.npr.org, and you can follow us on Twitter @nprfreshair and on Tumblr at nprfreshair.tumblr.com.

Transcripts are created on a rush deadline, and accuracy and availability may vary. This text may not be in its final form and may be updated or revised in the future. Please be aware that the authoritative record of Fresh Air interviews and reviews are the audio recordings of each segment.