Wiki: Semi-Sealing Rind Development

Gouda With Natural Rind & Natural Protective Geotrichum candidum Mold Development - CheeseForum.org

This wiki article discusses semi-sealing traditional natural rind development of pressed cheeses during aging. These encompass a range of rind development methods commonly used by cheese makers of old and still very common. This article does not cover high sealing and often more modern cheese protection systems such as:

  • Wax Coating (common on Gouda and Edam cheeses for protection during shipping).
  • Sealed Vacuum Plastic (common on many cheeses).
  • Cheesecloth wrapping and larding (common on some cheddars).
  • Milk based edible casein based bag or cloth wrapping cheese as common with large Gouda wheels. This is the same material used for modern labels on large cheeses.

Rind’s Function

Gouda With  Natural Rind & Natural Protective Geotrichum candidum Mold Development - CheeseForum.org
Gouda With Natural Rind & Natural Protective Geotrichum candidum Mold Development - CheeseForum.org

Rinds of cheeses are started to be formed during the pressing stage of making cheese, they are a critical component of cheese during aging as it protects the interior of the cheese to allow it to ripen harmoniously by acting as a barrier to unwanted micro-organisms and to dehydration. Its presence thus affects the final flavor of the cheese.

Salting plays an important role in natural rind formation. Heavily surface salted cheeses develop a thick, tough outer rind, typified by the Swiss range of cheeses. Cheddar, another natural rind cheese, is less salted than the Swiss varieties, and consequently has a much thinner rind.

Different natural rind developments are discussed below:

Clean Natural Rind

To create a truly hygienically clean natural rind with no induced microorganisms is very hard to do due to high chance of airborne wild contaminants and thus this method is almost never done.

Brine & Salt Rubbed Rind

Cheeses can be intermittantly once per week washed with saturated brine and then rubbed with coarse salt to build a hard thick neutral pH natural rind. It is important to keep the humidity of the aging environment down after rubbing the salt on as the resultant moisture on the rind as the salt is absorbed as brine can cause areas of unwanted yeast infection. Cheese makers often oil their cheeses after several weeks of brining and salting.

Oiled Rind

Gouda At 25 Days, Natural Rind With Natural Protective Geotrichum candidum Mold Development (Finger mark on left) - CheeseForum.org
Gouda At 25 Days, Natural Rind With Natural Protective Geotrichum candidum Mold Development (Finger mark on left) - CheeseForum.org

Oiling rinds with food grade oil is very common and discussed in the Wiki: Oiling Rinds article.

Benign Microorganism Rinds – Added During Pressing/Brining Phase

A protective rind is preferred from ????bugs.

Benign Microorganism Rinds – Added After Pressing/Brining Phase

Many cheeses have their natural rind coated with a permeable barrier to control unwanted microorganisms during aging. Examples are washing the rind with a fluid with live microorganisms such as beer, cider, wine.

Wiki: Oil Types

Several oils used on rinds to protect against moisture loss and against unwanted surface micro-organisms.

This Wiki Article discusses different oil types use to oil rinds of aged cheeses. Oiling cheeses is, along with having a rind with high salt and low moisture, a traditional method of protecting cheeses from unwanted surface micro-organisms. Why, frequency, and methods of applying oil to rinds are discussed in the Wiki: Oiling Rinds article.

Selection of oil type for aging oiled rind cheeses is a personal preference, any edible oil (when used in moderation) with relatively long shelf life before oxidizing and going rancid will work. Oxidation can be mitigated by adding citric acid to the oil. Saturated fats like tallow or lard are the most resistant to rancidity. Mostly monounsaturated oils like olive oil and canola oil have long life before going rancid. Mostly polyunsaturated oils like grape seed oil go rancid quickly.

The following list is of oil types and their pros and cons effects, listed from most to least popular.

Olive Oil

Several oils used on rinds to protect against moisture loss and against unwanted surface micro-organisms.
Several oils used on rinds to protect against moisture loss and against unwanted surface micro-organisms.
Olive Oil is about 75% monounsaturated oil (liquid at room temperature and semisolid or solid when refrigerated).

  • Extra Light Olive Oil imparts a light flavor.
  • Extra Virgin Olive Oil imparts a strong fruity flavor.
  • Herb infused olive oils will impart additional flavors. Basil is good for stronger cheeses, dill or crushed fennel for milder cheeses.

Rapeseed Oil

Rapeseed (canola) oil is about 58% monounsaturated and imparts a mostly neutral aroma and flavor.

Peanut Oil

Peanut oil, slight odor and flavor.

Butter

Butter has heavy saturated fats that last a long time before going rancid. However butter also contains proteins that over time degrade causing the oil to go rancid and thus it is not popular for oil sealing cheese rinds.

Butter does impart a popular buttery flavor.

Clarified Butter / Ghee

Clarified butter (commonly known as Ghee in India) is unsalted butter that has the milk solids and water removed so all that remains is pure liquid golden-yellow butterfat. The heavy saturated fats in clarified butter make it last a long time before going rancid. As clarifying removes the protein, it is comparable to lard.

As the process of clarifying the butter removes the milk solids, clarified butter imparts a light less rich buttery flavor than regular unsalted butter. But it can provide a nutty caramely “beurre noisette” aroma and flavor depending on how much the butter was cooked in the clarifying process.

Clarified butter or Ghee is available commercially or can be made at home from unsalted butter from recipes on the web.

Lard

Two 4 pound Gouda's at 30 days age with oiled rinds, one cleaned of mold, second with blue surface mold due to improper aging humidity.
Two 4 pound Gouda's at 30 days age with oiled rinds, one cleaned of mold, second with blue surface mold due to improper aging humidity.
Lard (pig fat), is about 40% monounsaturated fat and comparable to clarified butter.

Grape Seed Oil

Grape seed oil is high in polyunsaturates which can quickly go rancid thus it is only good for short aged cheeses as it will leave off flavors in cheeses aged for several months.

Sesame Seed Oil

Sesame seed oil has similar longevity issues to grape seed oil, it imparts a sesame flavor and additionally darkens the rind.

Other Oils

  • Soy Bean Oil
  • Avocado Oil, mostly monounsaturated fat.

Wiki: Dry Salting Rinds

Four 10 cm diameter Camemberts after dry salting.

This Wiki Article discusses dry salting cheese rinds, a procedure normally performed after forming the cheese and before air drying and aging. This salting method is commonly used with mold ripened cheeses such as Camembert & Brie and with washed-rind type cheeses. 

For the dry salt to be absorbed by the formed cheese, it must first dissolve and form a brine at the cheese’s surface after which it then diffuses into the cheese. As reviewed in the Wiki: Salt’s Function article, the % salt content in the type of cheese being made is critical. Thus it is important to understand the six main factors that control this method of salting cheese. 

Ambient Humidity

Soft rind dry salted type cheeses, are aged in high ~95% ambient humidity environment after dry salting. The high humidity is to prevent excessive evaporation of moisture from the surface of the cheese which would result in a dehydrated dense and tough rind being formed. Further these cheese types normally must remain with a high moisture content at their surface to enable their surface growth of molds, yeasts, and bacteria and in time their growth into the center of the cheese. 

For hard rinded cheeses, the ambient humidity is held relatively low @ 85% to encourage expelled whey to be evaporated resulting in a dehydrated surface layer of cheese, the start of the rind development process. Repeated applications of dry salt to hard rinded cheeses result in a steadily increasing dehydrated layer. 

Cheese Size

Four 10 cm diameter Camemberts after dry salting.
Four 10 cm diameter Camemberts after dry salting.

Generally, the cheese making procedure dictates the size of the formed cheese (good examples are generally uniform sized Camembert’s and Brie’s), and thus the procedures amount and method of applying the salt is matched to the size. 

However, if deviating in size of cheese, consideration should be given to the number of applications of dry salt and thus also the time to allow the cheese to reach it’s salt % content target range. 

Note, for large cheeses this becomes a problem because in time the build up of a dense hard layer from repeated dry salting the cheese’s surface will inhibit further salty brine uptake into the cheese and the dry salt will no longer be absorbed resulting in a cheese with sub-optimal % salt content. It is for this reason that large rinded wheels of cheese are often brine salted first, and then their rinds dry salted to i) reach the target % salt content and ii) to develop their hard rinds. 

Cheese Temperature

As with dry salting curds, the temperature of the cheese will be a controlling factor of the salt’s absorption rate. However their is ample time to absorb the salt while the fresh cheese is drying so this is not normally an issue and thus the temperature during dry salting more a function of the cheese’s drying and aging requirements. 

Salt Type

Standard sodium chloride, NaCl salt is used. It should be coarse granular sized rather than very fine to slow down the speed of dissolving into brine and absorption into the cheese. As with high temperatures, fine salt can result in a rapid flush of whey and fat which can wash away other salt before being absorbed resulting in incorrect salt % content of the cheese type being made. Different types of salt are discussed in the Wiki: Salt Types article. 

Salt Amount

As reviewed in the Wiki: Salt’s Function article, final salt content of the cheese type you are making is critical. Thus follow the cheese making procedure accurately on amount/weight of salt being applied versus weight of final cheese(s). If making several cheeses such as Camemberts in one make, ensure salt is allocated evenly. 

Salt Application

There are two salt application methods for dry salting rind cheeses: 

  1. For soft rind type cheeses, sprinkle measured amount of dry salt onto the whole rind including sides. Care should be taken to ensure the salt does not land off the cheese otherwise sub-optimal % slat content will be obtained.
  2. For hard rind type cheeses, rub dry salt onto the rind.

Wiki: Surface Defects, Oily

This Wiki article discusses surface normally unwanted oily defects of cheese. Note that oily rinds is a common side product in Swiss type cheese making where those cheeses are held at room temperature for part of their riping to create the eyes in the cheese. Oily rinds are normally associated with rennet coagulated pressed cheeses but can appear on other cheeses types. This article discusses the description, cause (normally ripening at excessive temperature), and solutions to oily surfaced cheeses.

Description

  • Surface layer of cheese has small beads of oil on it.

Cause

  • The most common cause is cheese is being ripened at too warm a temperature or fat content of milk is high and milk fat is seeping or sweating out which if left unattended can result in contamination.

Solution

  • Wash rind with warm water to remove excess oil and age at cooler temperature.