Home >
News Archive > November 2006
Brie & Camembert problem solved.
by Egon Skovmose on Wednesday, November 15, 2006
Here is a response we would like to share, which with the help of Dave Burley came out to the client’s satisfaction.
Question 1.
At this point I bought a refrigerator and replaced the
temperature control so, that the correct temperatures could be
achieved.
These solved many uncertainties in brie manufacturing, but one
problem is still evident. I add the mould growing culture directly to the vat, and although the mould grows well at some point, there is always a 1 mm layer of yellow, slimy layer under it.
This layer is ammonical in flavor and undesirable.
Question 2.
What could be done to prevent the formation of this layer?
Andrei
-------------------------------------------------------------
Answer by Dave:
I know exactly what your problem is and have seen it in others'
Brie and Camembert.
The condition is often called "slip skin" and the ammonia or
fishy smell can go along with it. Undesirable organisms which
have proteolytic enzymes (and make ammonia and other amines
by attacking the cheese proteins, softening them) and populate
the new cheese surface first, since these are happy - and need -
a low pH. You need to raise the pH of the cheese surface
quickly so that the P. candidum can get an early start (it needs a higher pH to grow.)
You to can use Geotricum candidum,
http://www.danlac.com/store/index.asp?product_id=449 along with the P.candidum
http://www.danlac.com/store/index.asp?product_id=253 a ratio of about 1 to 5. The G. candidum will populate the surface quickly and deplete nutrients needed by proteolytic organisms and raise the pH quickly to stop their growth and encourage the P. candidum.
This combination of these two molds will give a nice mushroomy aroma and prevent the slip skin and the ammonia odor.
In nature G. candidum comes in three forms:
1) 100% yeast (aka "lactum oidium"),
2) intermediate yeast/mold and can be used to produce a fragile white coating you may have seen on some French cheeses, but is not the P. candidum (or aka P. Camemberti) of Brie and Camembert and
3) the 100% mold form
http://www.danlac.com/store/index.asp?product_id=253 used in combination with the other desirable surface microorganisms in combination (never alone) like P. candidum or B.linens, which need a higher surface pH. Maintain about 80% humidity in the curing chamber for the Brie. I believe Danlac's G. candidum can also be used with B. linens and is the mould only form.
Put dried cultures directly in the cheese milk no typtone or glucose
or nothing.
I do not recommend you dip or spray a solution of the mold as is often recommended, as you will be inviting contamination of the wet surface. It is important that the cheese surface be dried in a low humidity – between 50 and 70% - for a day before placing it in the curing chamber. This dry surface helps prevent overgrowth by undesirable organisms.
Response from Andrei:
Thanks a lot again. I wish I could get in touch with you about half a year ago.
It would save me from a lot of mistakes. I guess it would not be as much fun then.
Cheese Yield Facts.
by Egon Skovmose on Sunday, November 5, 2006
Cheese yield.
The amount of cheese manufactured from a given weight of milk is cheese yield.
Factors which influence cheese yield are:
1. Composition of milk
While butter manufacturing/production is mainly depending on the content of fat, you will not find that in cheese production, here you have to consider the milk’s content of protein, lactose, salts and water content – although butter has water. Cheese making is also more complicated then butter making. Cheese has to be cured for a certain time, depending on the type. Therefore, it is not normally easy to set general norms for cheese yield.
You can though, give average numbers to compare to an estimate how much milk is used to make how many kg of uncured (fresh) cheese is made.
Milk used per kg of cheese can roughly be given as:
% fat in solids------------- 40% 30% 20% 10%
Kg. cheese milk / kg cheese 10 - 11 - 12 - 13
Fluctuations in the milk’s content of protein and milk fat has the largest influence on variation of cheese yield at a constant moisture level. According to Danish Dairy Research Station (86. report) you can anticipate that approx. 90 % of the milk fat, approx 75 % of protein and approx. 5 % of lactose and half of the salts from the milk go into the cheese. A higher content of fat & protein will obviously give higher yields.
Protein and fat percentage varies during the season and you should observe these and modify the anticipated yield.
Use the LactiCheck from Danlac Canada Inc.
http://www.danlac.com/lacticheck.shtml to check these variations in fat, protein content and to get results in 85 seconds, so you don’t have to wait on other labs to provide these. From the above and from talking to experienced cheese makers you will get to know the ratio between fat and protein (casein) importance. In the 113. report from the same Danish source, using Danish milk the research lab found following correlation:
Protein percentage = (0.5 x fat percentage) + 1.4
This formula gives following correlating values:
Fat % ---- 3.00 3.50 4.00 4.50 5.00
Protein % 2.90 3.15 3.40 3.65 3.90
Note: do not use these numbers as pure science but only as example. Make your own calculations for your part of the world and animals.
The insoluble fraction of the milk: fat, casein and some salts, contribute almost wholly to the solids of milk (some are lost in the whey though such as lactose, lactoalbumin, lactoglobin and certain salts).
Cheese yield is important in determining the unit cost of cheesemaking. A yield of 9.5 kg of cheddar cheese, accepted as a general standard factor in evaluating costs, indicates that a cheese plant produces 9,500 kg of cheese form 100,000 liter milk, but if in practice the actual yield is 9.0 kg and only 9,000 kg of cheese are realized, and then the original cost figures estimates are not truly representative.
Yield by the Van Slyke Formula:
In 1894, Van Slyke observed the composition of incoming milk and the resulting Cheddar cheese weight in a number of small cheese factories. From these data, the classical formula for estimating Cheddar cheese yield was derived.
[(0.93 X Fat + casein-0.1) x 1.09] "divided by"
[100 – Moisture percent]
= Cheese yield (kg cheese from 100 kg 3.5% fat milk
Loss and shrinkage in cheese production:
In cheese production as was mentioned before there are certain conversion numbers for the milk components. These losses are unavoidable, although it would be in your interest to limit them.
As far as protein is concerned, will be coagulated by the rennet, following can influence these.
Also the fat loss will depend on curd handling technique. Fine cutting and stirring will increase losses. So be gentle when cutting and stirring until the curd has a good strength.
Using mechanical separation of the whey to regain much of the fat in the whey, however you do not want to loose so much fat that the content in the cheese becomes too low.
Under all circumstances the whey will contain a part of the cheese milk fat and at normal cheese technique will the whey average fat content be:
Cheese type 45+ ----- 30 +--------- 20+
Whey fat % 0.3 – 0.5 ; 0.1 – 0.2 ; 0.1 – 0.2
As mentioned before, we have to make sure the cheese milk fat percent is high enough so the desired fat in solids gets high enough. Normally you should calculate cheese fat in solids as 1 -2 % higher then desired. Why? Cheese milk fat percent must be adjusted carefully as a variation of 0.05 % in it will give a variation in the fat percent in solids in the fresh cheese of a size which can be seen in following numbers:
Cheese type (fat/solids) 45+ 40+ 30+ 20+ 10+
Variation in fat in solids 0.45 0.55 0.60 0.80 0.90
Storage loss.
Matured cheese requires storage of 2 – 4 months and in this period you can expect a certain loss, as cheese under storage will give off moisture and different gasses due to microbial / enzymatic activity. So, limiting, controlling and understanding these will be part of controlling losses. This does not apply to rindless cheese although some semi-permeable plastics packages allow some gasses to escape. Gases are an insignificant part of the yield in any event.
Conclusion.
As you can see from the above comments, controlling yield losses can make a difference in the bottom line and there the better the yield the darker the bottom line is going to shine. High quality cheese should always be the aim as that will always result in better prices and demand.
Good control of yield will mean a consistent and profitable product and a solid customer base.
____________________________ _________________________________ ____________________________
