Cheese making
In parallel with the synthetic biology work, we are experimenting with cheeses made from powdered purified casein, and using vegan oils to replace milkfat. This page documents our cheese-making efforts.
Experiments
- Making normal non-vegan cheese and several partially vegan cheeses.
- Time: 1 pm on Sunday April 20th
- Location: 2429 Adeline St. Oakland, CA.
- Making non-vegan cheese starting from micellar casein powder
- Time: 9 pm on Monday July 28th
- Location: Omni, Oakland, CA.
Books and resources
- The Joy of Cheesemaking
- This is a really great book for cheese makers who want both practical step by step instructions and a decent amount of theory. What really makes it shine is its inclusion of specific instructions for dealing with e.g. lactic acid bacteria from different suppliers and extremely clear instructions that include helpful tables an illustrations. This book is targeted at home cheese makers.
- We have it in epub only (no pdf). Juul has a physical copy.
- American Farmstead Cheese: The Complete Guide to Making and Selling Artisan Cheeses
- This is a really nice theoretical and practical summary that goes into just enough detail for an interested citizen scientist without overwhelming the reader. It does not contain recipes or practical step by step instructions so it must be supplemented by e.g. The Joy of Cheesemaking, but it has much more detail on the science of cheesemaking. This book is targeted at small scale cheese producers.
- We have it in epub only (no pdf). Juul ordered a physical copy but it has yet to arrive.
- Cheese: Chemistry, Physics and Microbiology
- This is the cheese science textbook. Probably not your first stop if you're looking for an overview of cheesemaking, but goes into much more detail than American Farmstead Cheese.
- We have it in pdf. No physical copy.
- Process of Producing Synthetic Cheese
- An imitation or synthetic cheese product is produced by reacting an acid precipitated casein with a basic calcium salt to produce a calcium caseinate solution, adding acid to adjust the pH of the calcium :caseinate solution, forming a curd of the calcium caseinate by treatment with a coagulating enzyme and admixing the curd with an edible oil or fat, a non-toxic emulsifying agent and acid to produce a :cheese-like product having a taste, texture and flavor similar to natural dairy cheese.
Online cheese cave
Most hard cheeses that are the least bit interesting need to be aged at colder than room temperature and high humidity.
We've built a wifi-enabled humidity and temperature controlled logging cheese cave out of a modified wine chiller: Cheese cave.
Cheese press
The design should be mostly self-explanatory from the photos. The press has to be attached to a table somehow so it doesn't tilt, then a weight is attached to the end of the lever-arm (e.g. a bucked of water).
The cylinder is made made from a mostly non-tapered food-safe tupperware-type container. 100% non-tapered containers would be preferable but are hard to find. If you find a good source for food safe cylindrical plastic or stainless steel in appropriate dimensions then definitely let us know.
A sushi-mat should be placed under the cylinder and the curds should be wrapped in cheese-cloth and placed in the cylinder.
The white disk that presses the curds is cut from a plastic cutting-board.
The striped piece of wood is a cheap bamboo cutting board. Screws and metal likely to get in contact with water (near the bottom) are all stainless steel.
Rennet
We're using microbioally produced pure chymosin. It's what industry uses for most cheeses and it's also the most effective and preferable rennet for most hard cheeses.
We've purchased Chr Hansen CHY-MAX from The Cheese Maker online store.
This is getting a bit close to its expiration date and Chr Hansen has a new and better second-generation chymosin called CHY-MAX M. Which is also available from The Cheese maker. Perhaps we should order it.
Milk-fat / Oil
For non-vegan comparison experiments we can use ghee, but for actual vegan cheese we need a milk-fat substitute.
It may be hard to find a suitable vegan substitute. What are the important properties?
We can probably assume that melting point (stability at room temperature) is an important factor. It may also be that interaction with caseins is important for micelle formation. This should be easy to test though.
Palm Mid Fraction Oil (PMF)
- Melting point: 35-36C
- No strong flavors
- Concerns about sustainability of palm oil farming
More info on the different types of palm oil.
Cocoa butter equivalents (CBE)
These are fats rich in symmetrical disaturated TAG (SUS) that behave like cocoa butter in all respects and are able to mix in all proportions with cocoa butter. The desirable charac- teristics of cocoa butter are due to the SUS TAG, which provide a suitable melting point and solid fat content, resulting in rapid melt in the mouth and cooling sensations. Palm mid-fraction (PMF), which has a high content of POP, is easily formulated with other SUS fats for chocolate products (Berger 1981). About 70–80% PMF with 20–30% shea or sal stearin, or 60–65% PMF with 20–30% shea or sal stearin and 15%–20% illipe, are suitable for plain chocolate and for milk chocolate with 15% milk fat. The compatibility of cocoa butter (CB) and CBE is affected by the addition of milk fat and its fractions into the product (Sabariah et al. 1998). Eutectic interactions between anhydrous milk fat (AMF), CBE and CB were noticeable due to the different polymorphism encountered in these fats. Cocoa butter-like fats can also be formulated with interesterified oils. Blends suitable for butter-cream fillings in biscuits may be formulated from palm stearin/palm kernel olein (25:75) or palm stearin/palm kernel olein/palm kernel oil (25:37.5:37.5) (Noor Lida et al. 1997).
- From Vegetable Oils in Food Technology - Composition, Properties and Uses
Cocoa butter
- Melting point: 34 to 38C
- Flavors may be a problem
- Expensive
Shea butter
- Melting point: 40 C ?
- Cost: ?
- Environmental concerns: ?
- Need more research.
Sources:
- high-melt point shea starts melting at 40 C.
Coconut butter
- Melting point: ~25C
- Flavors may be a problem
Fully hydrogenated oils
We could change melting point of oils with hydrogenation. This isn't popular due mostly to concerns about trans fats, but trans fats should only be present in partially hydrogenated oils. It seems that these "bad" oils are not easy to buy in small quantities. It may just be that no-one advertises their product as "hydrogenated".
We probably can't hydrogenate oils ourselves, since it requires bubbling hydrogen through the oil at high temperatures in the presence of a metal catalyst :/
Lactose
Since there are no vegan sources for lactose, and since Lactic Acid Bacteria (LAB) are an important part of cheese-making, we will need a replacement.
LAB can grow on other sugars, but we do not know if their expression profile or growth rate will be different or whether this will affect the taste of the cheese. We can do two things:
- Make cheese with lactose-free milk vs. lactose-free milk with lactose added back in.
- Research to understand LAB and its use in cheese better.
We know that most of the standard bacterial cultures used in cheese making can also grow on other types of sugar than lactose. Lactose is a disaccharide of galactose and glucose, so just replacing the lactose with its monosaccharides would be a good starting point. We could also replace the glucose with a glucose dimer such as maltose or even trehalose to slow down its bacterial utilization a bit.
There’s plenty of sugars to choose from, so we have no doubt we can feed the desired cheese-making “flora and fauna” with a combination that is much better human-digestible than lactose. Finding a combination that results in the same flavor profile as lactose may take some experimenting.
Our top priority for this first phase of the project is to produce the cheese proteins themselves though – that’s the core of the cheese. Everything beyond that falls more under recipe development.
For the non-vegan control, we can buy powdered lactose. We can also easily get [http://www.lactaid.com/ lactose free milk, but I'm fairly sure it still has some lactose. We may be able to break down most of the remaining lactose by adding a lactase enzyme supplement.
Casein
There is a protein supplement product available that is advertised as 100% micellar casein at $28 for two pounds. It claims to be 100% non-denatured micellar casein with no additives. It's not molecular/lab grade, but it may be the best we can get.
Sigma-aldrich sells kappa-casein but it's only >=70% pure and costs $600 for 1 gram.