31 January 2010

A Guide To Liquid Nitrogen

Liquid nitrogen allows us (chefs) to instantly freeze ingredients and products in a way that was previously impossible. This method has opened up new possibilities in the kitchen. Here at Burch & Purchese we are always on the lookout for new and improved techniques and methods, so we use large quantities of liquid nitrogen and we have done for some time now. If you are new to this method of rapid freezing, here is some useful information. We recommend though that you research thoroughly before attempting to use a potentially dangerous product.

Nitrogen makes up nearly 80% of the earth's atmosphere by volume and the element was discovered in 1772. Liquid nitrogen is a cryogenic liquid that is created by fractional distillation, (separating chemical compounds by their boiling points), of liquid air. Nitrogen has a low boiling point, lower than oxygen, so it can be distilled easily. Liquid nitrogen has a boiling point of around -196 degrees C and freezes at -210 degrees C. It also boils upon contact with warmer temperatures, this is called the Leidenfrost effect http://en.wikipedia.org/wiki/Leidenfrost_effect, as it boils it evaporates into nitrogen gas. Inhalation of too much nitrogen can cause dizziness, nausea, loss of consciousness and death, so it is VERY important to work with liquid nitrogen in well-ventilated areas.

Liquid nitrogen is stored in specially designed containers called dewars. Dewars are insulated, pressurized containers equipped with safety releases and rupture discs that help prevent pressure build up and explosions. As highlighted above, the canisters should be stored in a well ventilated area.

As well as adhering to correct storage methods, there are other important safety issues to remember. The extremely cold contents of the canister means that any uninsulated metal piping will be at LOW temperatures, so do not touch with bare flesh to prevent freezing and possible tissue damage. When using liquid nitrogen, protective gloves, goggles and face shields are recommended.

Heston Blumenthal brought liquid nitrogen to the attention of most people with his scrambled egg ice cream, although he certainly was not the first to use it in the kitchen. We associate liquid nitrogen with ice cream making and this is probably the most common use of it but really the possibilities are endless. For a quick 'nitro' ice cream, take a bowl with some ice cream base of choice and stir with a spoon/spatula whilst pouring in (slowly) liquid nitrogen. Once the correct consistency is achieved you can serve the ice cream immediately. Be careful not to add the nitrogen too quickly and ensure the ice cream is not consumed at too low a temperature to prevent frozen burn to the tongue or other areas of the mouth.

Egg & Bacon' at The Fat Duck including 'nitro scrambled egg ice cream'

Advantages of making ice cream with this method is the lack of traditional preservatives and anti freezing ingredients that normally ensure a smooth and consistent product. Sugar, of course is added to ice cream, not just for its sweet flavour profile but to prevent ice crystals forming and ensuring a 'scoopable' product. Sugar derivatives and alcohols do the same thing but are now not needed as liquid nitrogen ensures a smooth and consistent product every time. 

Obviously, being able to rapid chill a product has huge benefits to the safety conscious. Being able to chill a stew or custard in seconds significantly reduces the chances of bacteria development in foods.

Powders and fine preparations can also easily be achieved, in particular tricky high fat products such as nuts. When grinding nuts or other high fat products, less than satisfactory results are often achieved due to friction increasing temperature and leaching out oils. Now, almonds say, can be frozen in liquid nitrogen and blitzed to produce a superior result.

Vegetables and fruits can also be frozen to tenderize them. Ice crystals are formed which prick tiny holes in the membranes of cells inside these ingredients. Once thawed, the fruits & vegetables are tenderized but still retain some of their original texture and flavour. Fruits and vegetables once frozen to a low enough temperature can also be broken or shattered to produce a different presentation to finishing a dish or for other applications. 

Liquid centres! This is an area we are looking closely at, as the possibilities are seemingly endless. Imagine freezing something that normally can't be frozen? e.g. vodka in a normal freezer won't work, but in nitrogen it freezes hard. Now take this frozen 'ball' and encase in chocolate or ice cream and allow to defrost. What would happen? Well, we wil be working on this in the next couple of weeks and will post our results here.

As long as the medium is respected and all of the important regulations and safety measures are in place then liquid nitrogen is an extremely exciting and useful tool for the modern chef. 

http://www.restaurantecalima.com/ - Chef Garcia's restaurant is at the forefront of low temperature cooking.

http://cookingissues.wordpress.com/?s=liquid+nitrogen - Nitrogen articles on Cooking Issues

Happy experimenting!!

24 January 2010

Burch & Purchese Dishes - 19 Sweetcorn Cream, Curried Popcorn & Maple Jelly

We've been working on these flavours for a while and they seem to compliment each other very well. Smooth, slightly sweetened sweetcorn cream sits in a bowl with popcorn ice cream and curried warm popcorn. Maple gels and microplane toasted pecans finish this simple dessert. The curry really lifts the dish and the popcorn add contrasts in texture and temperature. Really fragrant young corn shoots are an added garnish and we are happy with this dish so far. Lots to do though before this is the finished article, we have just got to keep refining our work.

23 January 2010

Books For Inspiration

Regular readers of this blog will know of our passion (obsession?) with cookbooks, we greedily snap up the latest titles and hoard a substantial amount of books, to the extent we run out of room! These books come in most useful when researching dishes or ingredients, when looking for a particular cooking technique, or just to help us decide what to cook on a Sunday. The books above though, and books of that sort, often help us in more ways than a cookbook. When creating dishes or designing new creations we find books on food science, art & design and historical books an inspirational source of ideas. The science books help us determine the best ingredients to use for a specific technique, for example 'Food - The Chemistry Of It's Components' highlights new and interesting uses for hydrocolloids. It also has invaluable nutritional information which helps us decide quantities of fats, carbohydrates, sodiums and so on in developing a balanced dish. Cookbooks, depending on the author, can't always be trusted to provide the most accurate information. Usually a cookbook is the product of one chef/cook's opinion and as you know opinions are not always based on fact. The research we conduct, partly utilizes fact based food chemistry book reading and we find this really helps our understanding of ingredients.
We find art & design books fascinating and it is surprising how much a chef can take inspiration from these. On a practical level some of these books help us here at Burch & Purchese, in forming new ways to package our products. Sometimes the packaging helps to evolve product but making us think 'outside the box' so to speak. The design material we have also provides excellent examples of shape and structure, these help us in creating new designs for a cakes and dishes. Just as nature can inspire structural design, eg. Gaudi, structural design can inspire pastry chefs in their creations. These books help us in our work.
Books by chefs/cooks from another era are also immensely useful, not to mention enjoyable. The works of Careme, Brillat-Savarin and even further back Apicuis provide astounding facts on nutrition, dish construction and ingredients. It is amazing they were able to conclude things that we take for granted because of technology available to us. We take inspiration from these chef's notes on seasonality, menus and other subjects and try to incorporate their teachings in our work. In all it helps to broaden your reading spectrum, you may be surprised at what you discover! Below are Amazon links to the books mentioned.












Further Links To Burch & Purchese

Earlier this month we posted a piece on a special dinner in Sydney in which we were able to work with the talented Australian chef Adam Melonas. Well here are two blog accounts of the dinner for you to have a look at. The first one is on the lovely Lyndey Milan's website, Lyndey has been a friend of ours
for years now and hosted Adam's dinner click here to see:


We hope you enjoy reading these posts and discovering the other interesting articles on these blogs, we will keep you posted on lots of exciting events planned for later in the year.

14 January 2010

Great Time To Start Making Jams

We don't seem to have much time on our hands these days but when we do we like to indulge in our hobby of jam, preserve and spread making. It is such a great way to capture and preserve a flavour and really the only limit to what you can jar is your imagination.
We make product for retail, but often produce conserves if we see some appropriate fruit at the market. At least twice a week we get to one of our local markets early to see what is available, this morning we managed to pick up some beautiful, plump Tasmanian cherries which we are going to preserve in an acidulated vanilla syrup.
If you are living in the Southern Hemisphere as we are, now really is the time to start looking for fruits, flavours and aromas to bottle or jar for the coming Autumn months. We saw some  excellent quality Victorian strawberries this morning which were very inexpensive and would be ideal to jam or puree (and frozen) for when these fruits are unavailable.
Just follow a few basic sterilisation rules and these will all be perfect for consumption for a long time, long enough even to give as Christmas presents which is exactly what we did this year. If you are interested in preserving then there are a number of great books on the subject which will help you with sterilisation and some of the trickier details such as ph levels of fruits, brix and instruments you may need to invest in. We would love to know of your successes so please let us know how you get on.

Check out wikipedia's explanation of Brix http://en.wikipedia.org/wiki/Brix

Burch & Purchese To Talk Chocolate At Hotshot & Teapot At The Melbourne Food & Wine Festival 2010

Taste and compare single-origin and single-region chocolates from around the world. Darren Purchese will reveal the secrets to using the perfect variety for every occasion. For tickets click here http://www.ticketmaster.com.au/search?tm_link=tm_homeA_header_search&q=HOTSHOT+%26+TEAPOT&search.x=47&search.y=2&camefrom=CFC_AU_MFW11

13 January 2010

Burch & Purchese To Hold Pastry Demo's At Melbourne's Newest Cooking School

Ever wondered how a Pac-O-Jet Works?
What's the secret to a perfect chocolate mousse?
You would like to know what makes a great custard?
Burch & Purchese are holding a series of pastry demonstrations later this year we are pleased to announce. Melbourne's newest and best equipped cooking school 'Class' run by the talented people at Rely Services is open soon, with a fantastic schedule of chefs all on hand to help you improve your cooking. We look forward to seeing some of you and helping your skills develop. Please contact  relyservices.com.au for details of this years schedule & soon as their website is up we will post here

12 January 2010

Lemon Meringue Pie Anyone?

After the holiday season has passed you would think we have slowed down a little, well not so. Ian got to work on making these cool lemon meringue pies for a private function earlier this month. Sometimes with all of this modern cuisine, and new techniques, you can forget some of the older dishes that have stood the test of time. The reason people still make and love these creations are for one reason, they are delicious! We were ably assisted by our ever helpful commis Marie who, as you can see, really enjoys her work as well.

11 January 2010

Great Night With A Great Chef

Chef Adam Melonas

The famous Octopops

Tuna sashimi

Glad to help

Adam at work

Yoghurt Risotto

Thermo reversible Nutella spheres

Liquid centre chocolate doughnuts

If you are a regular reader of this blog, you will know of our admiration for chef Adam Melonas. An Australian chef who has worked abroad at some of the finest establishments and, who was until just recently, Paco Roncero's  main creative chef at their lab in Madrid. Adam has been extremely helpful to us in the past and he has a generous spirit and humble approach to his craft. When we heard Adam was back in the country to promote his new venture in New York later this year we offered our services in a special dinner that took place in Sydney last week. Adam politely accepted and we went to work on some of the dishes that Adam has spent years developing. It was a real pleasure to work with Adam and see first hand the famous Octopops, Tuna sashimi and surf 'n' turf. Adam was generous enough to provide insight behind the creations and we have promised to collaborate further in the future. We particularly were impressed with the thermo reversible technique developed by Adam in his liquid chocolate centre doughnuts. You can be sure that we will be exploring this technique further and will post details in due course. If you are not familiar with Adam you should check out further information on him at http://en.wikipedia.org/wiki/Adam_Melonas. The dinner was a great success and Adam received much deserved praise for his dishes from the likes of chefs Tetsuya Wakuda & Brent Savage who were present. Thanks Adam and good luck with New York.

03 January 2010

New Designs In Celebration Cakes

We have some cool new cake designs that we have been working on for 2010, as soon as we can we will let you know the new techniques and flavours we are using. We are really excited to show you some stuff Australia has never seen before. Watch this space!!!  

02 January 2010

Burch & Purchese Dishes - 18 Pinenut Cream With Gingerbread, Green Tea & Yuzu

Unusual flavour pairings that combine to create a sensational mouthful. Spiced and dried gingerbread, sharp and tangy yuzu as well as fragrant green tea all marry well with the nutty mousse. Toasted pinenuts, raspberry mayonnaise and chocolate clay garnishes add contrasts in flavour and texture as well as showcasing new techniques in cooking.

How To Get A Reservation At Elbulli

If you want to be one of the lucky few to dine at the world's best restaurant, then you have to give yourself the best chance possible. Every year close to 2 million people request one of the 6000 seats available, amazing odds that can be shortened with a few tips.


Check the website for the official reservation request time. Elbulli only consider requests that they receive in the specified time. This year it's 1st Jan to middle of Jan, so you need to get in quick!!


The email address is bulli@elbulli.com and the man in charge is Senor Garcia.


Don't be demanding - you are less likely to get a reservation if you specify a particular date, time or anything else. Best to ask for a table at any time and date for 2 persons.


Keep the email short and be polite.


Cross your fingers and hope for the best, they will get back to you regardless of the outcome probably by March.

Good luck, it's worth it!!


Happy New Year to all of our followers and readers, 2009 really was a fantastic and exciting year for us and we hope 2010 will be even better.
Since starting this blog in the middle of last year we have tried to bring you news and images on current food trends, book reviews and the latest news on our business and travels. We have had (to date) over 6500 unique readers and we hope that we have informed and entertained. Highlights last year included, trips to elbulli & El Cellar de Can Roca, working with Ramon Morato, dessert only dinners, Melbourne Food & Wine Festival, visits to Singapore & Japan and lots more which can all be found in the labels and archive files of this blog.
Next year we hope to top that impressive list and we will bring you all of the information here for you. Thanks for all of your support in 2009 and we look forward to having you here in 2010. Darren & Ian