Saturday, 10 January 2009

Temperatures, an Experiment

So, as part of learning some of the stuff I feel I need to learn to really get a handle on trying to make skyr, I did some experiments in maintaining a temperature.

A number of cheeses have a much quicker process time; higher acidity, and higher temps, may work to form a curd in a shorter time period. The recipes for skyr all seem to suggest a coagulation time of 12 to 24 hours. That’s a long time to maintain a temperature. Certainly 24 hours means going overnight, and a period of unsupervised sitting.
Up until now I had been following an idea I’d read somewhere of putting the pot in the oven with the oven light left on. (Mind you, I also had a less concrete idea of what temperature I was trying to maintain.)

Today I tried a series of tests.
First, a whole lot of reading had suggested that a good temperature to maintain during this process would be between 100 and 110 F. Apparently that’s an optimum temperature for rennet to coagulate the milk solids into curd. Even if it ends up not being the temperature I finally decides works best for skyr, it was still a good starting point.
So I tried a container of water at 110F in the oven. I had preheated the oven just a fraction, by turning it to it’s lowest setting for a few minutes only, then placed the uncovered container in the center and left the light on and door closed. Within an hour and a half the temperature had dropped to 96 degrees.

A second test had water at a temperature of 106 F in a wide-mouthed thermos. (I felt that I had better thermoses with narrow mouths, but didn’t fancy the idea of trying to get coagulated milk out of them. Certainly it wouldn’t work for anything that I’d hoped would form a firmer curd!) In the hour and a half, the temp had dropped to 96 degrees.

A third test had water of 109 F in a crockpot. Unfortunately, it’s a slightly older style slow cooker, and has only a low or high setting. I gather the new models also have a warm feature. In an hour and a half, the temperature ROSE to 126 degrees.

These had been my first and easiest ideas. And I guess I haven’t found an easy answer. I have a couple of other things to try next…

Tuesday, 6 January 2009

Not Skyr

Yet again, I have been vanquished in the quest for skyr.
This time I again tried the skimmed milk recipe. I was hopeful, because early on I was seeing some curd separation, but in the end didn’t get anywhere near a useful degree of coagulation. (Is there a happier word one can use to describe the actions of rennet when making cheese products?) And to my sense of taste, there really wasn’t any kind of marked degree of change from the flavour of milk. It was ‘not milk’ in flavour, but without any of the tang or faint acidity I’ve come to associate with skyr.
I did get to try out the new piece of equipment my loving husband gifted me with for Christmas.

A nylon jelly strainer system from Lee Valley. Far simpler for clean up. Cheesecloth may really be washable, but I think I prefer to save it for theatrical costume uses, because it’s nothing but a pain for use in the kitchen. (Well, perhaps if I had a kitchen dedicated to culinary experiments that wasn’t also full of the rest of our lives…)

But I’m starting to think that some of the comments I’ve made about the iron-smelting experiments that go on outside our house also apply here. Too many unknowns and too many variables, and never working towards setting some constants.

I’ve had several recipes I’ve been playing with simultaneously. There are several possible types of milk I can use; some of the recipes specify, some don’t. I have two different kinds of rennet, both of which are vegetable-based, so are a variable in themselves. There are a couple of different methods suggested. There is the variable of quantity: do the reactions I’m looking for require certain quantities before they occur? Are the proportions for reaction a constant?

In many ways as with the iron smelting, some of the same questions occur, and I can just plug a different noun or verb into the question, and it’s just as valid when applied to my experiments with skyr. (Scary, eh?)

* To begin with, I’m trying to experiment to create a product I don’t have much familiarity with. There is almost no experience with skyr in Canada, other than in specific communities with a cultural heritage that has kept it alive. (As in so much else in my life, I had never particularly heard of skyr, or had any interest in its existence, when I was growing up in Manitoba, a stone’s throw from Gimli and its Icelandic community. Turns out my mother knew about it, and liked it, and used to be able to buy it in the grocery store when she was younger! Thanks to the whole new world of major grocery store chains, and countrywide supply lines, that’s no longer possible. And now I live a wide province away…) So all I really know of skyr is from other people’s descriptions, which are never quite the same, and recently, thanks to a friend’s importation of some from a small producer in Manitoba, or some commercially-produced skyr brought back from Iceland. And whether either of these is typical, true skyr, or the skyr one might expect to make from the few available recipes, is as much a guess as any other.
Even from the few tastes I’ve had of skyr, I can’t really describe to my own satisfaction how it tastes. Before I’d ever had any, my interpretation of other descriptions led me to think it would be a little bit like yoghurt meets creamed cottage cheese. (Again, I had to work with products I’d already tasted. I’ve never had Quark; so don’t know where it fits in the spectrum.) When I did taste skyr, I think I was surprised that it wasn’t tangier. Because I’d been thinking about yoghurt, perhaps like a yoghurt cheese, I was expecting the same amount of acidity. (One of the things that keeps me from really enjoying yoghurt in large quantities. Too sharp a taste.) It wasn’t. But it also wasn’t like clotted cream, though the texture wasn’t that far away. It was less ‘glossy’ and loose than sour cream. (Oddly, although much sour cream is “sour” in taste, I find it less acidic than yoghurt. I feel there’s probably science involved here, which I need to know more about.) And again sour cream is still too sharp a flavour. And skyr can be more dense-seeming.
I have had some cream cheeses that are more like skyr in taste than either yoghurt or sour cream. They seem to be less typical of cream cheeses though.

So, here I am, trying to make something I’ve only tasted occasionally, can’t happily describe, even to myself, and have only very intermittently had brief access to.

Good start!

*I’m also not finding a lot of concrete information about skyr. Mostly just the same stuff re-paraphrased elsewhere, or some vague descriptions. And not much by way of recipes. I have one recipe that came via a friend, and one cookbook of Icelandic recipes from the Lake Winnipeg area that has two or three different takes on it. There’s a bit of discussion on the internet, which I’ve gleefully bookmarked, but nowhere near the amount I thought I’d find. Which is odd, because I know I’ve talked about skyr and figuring out how to make it for years now, and only recently got down to seriously trying to do something about it. I am sure I’m not the only one. In fact, by the number of Google searches that have hit on this blog by the search word ‘skyr’, I KNOW I’m not alone in this quest!

*What recipes I can find, seem to have no consensus as to what milk to use, skim, partly-fatted, whole milk, buttermilk… Admittedly, in searching for information on Viking Age skyr, it’s not like there’s likely to be a recipe or archaeological evidence, so information from traditional practices would be a good starting point. But even that seems a bit vague.

[I should point out that I’m mostly working from my own culinary library, which isn’t totally sketchy, or what I can find on the internet. I live rurally and have no easy access to libraries anymore. Give me a lovely university library and I might make some more headway. Or not. Even if the information is really available and out there, sometimes it can be well hidden!]

Part of my brain says higher fat content milk would give more milk solids. And that maybe my lack of coagulation is because I was using skim milk. But common sense suggests that historically milk would be processed differently and separated into different components for different uses. Cream becomes butter. So it would be the thinner milks and whey that might be made into cheeses. And there are Scandinavian cheeses that are made from whey: Gjetost and Mysost. Some of the things I’ve read about skyr, say it is a low-fat cheese. But then some of the recipes don’t mention that at all. I may not be able to find a definitive answer to that, but some further experimentation may be able to tell me how I need to make it to have it work.

*I need to figure out what the differences are between animal- and vegetable-based rennet. I have no particular preference which I use, being a carnivore, but if I can get the vegetable-based version to work, then it will be suitable for my non-meat-eater friends and relations. In the long run, it will probably hinge on what’s available to me. But I do need to learn if there are variations in how well each work, and in the amounts that should be used. The recipe I was just trying asked for twelve drops per 4 quarts of milk. I noticed that the rennet bottle itself suggested five drops per 1 litre. Hmmm… Mind you, I based my amount of rennet on that 5drops per litre, and did NOT get any really tangible curd formation. It ‘looked’ liked it was working, but when I went to strain off the liquid, it was far more liquid than solid.
And I don’t think that just giving it more time is the answer either. I did that with one of the very first attempts, and by the time I’d developed some thickness that was strainable, the milk was somewhat past human consumption. Even our cats, who adore dairy in any way, shape or form, were completely disinterested!

*Temperatures. When they say heat to boiling, do they mean heat it till it IS boiling, or until it reaches that temperature? Or maybe even boil for a bit of time? And cooling to lukewarm… What is lukewarm exactly? Does it matter? Am I over analyzing?

Hmmm… I was just grubbing about in yet another cookery book, thinking about an offshoot from this project that would involve trying to make something else, where I can find more info, and lo and behold! Have come across some instructions to do with yoghurt making that say: Sterilize 1 litre milk by bringing it to the boil, and simmering for two minutes to kill off any undesirable bacteria.
Now, there is the first reason I’ve seen for heating to the milk to boiling. No other source has given a reason. Is this why I should be heating the milk? And this one gives the instruction about two minutes of simmering.
This same recipe also gives a temperature for ‘lukewarm’ of 38-43 degrees C, or 100-110 F. (which is different than what I’d been doing in this last experiment.) I’d found some other suggestions of 80 – 85 F.

Entirely possible that temperature is one of the variables that is contributing to the different results. Certainly I suspected that the temperature I’ve been leaving it to sit at might have an effect on coagulation and formation of a curd, and is a bit hard to control. It is winter here in Canada, and I live in a cold house (electric baseboards and a programmable thermostat to save on hydro costs.) At a different time of year, the ambient temperatures will be greatly different.

I think I also need to experiment with some other methods for maintaining a temperature, and maybe try a higher ‘lukewarm’ temp.

I do believe, though, that I need to put aside questing for skyr until I’ve learned a little more about the rennets I have available. If I can get a handle on the processes and results when I’m working with something a bit more obtainable, like making a yoghurt, where I can easily buy commercial yoghurt for a starter, and know what it should taste like, or some soft cheese, then I may be able to apply the experience again to trying for skyr. Though I may also be limited to the suggestions of how to make a skyr starter, since the availability of real skyr is extremely intermittent.

Sadly, all my previous experiences with cheese-making and the like are just too many years behind me now to be of use. I’m really starting at the beginning all over again. I just have to hope I’ve learned a bit of patience, and can approach this methodically, and solve the mystery!