Freezing Technology Basics

Thank you for visiting. We hope you find it useful and informative.

We ask that you consider these two notes of caution:

First, this section has been created for the food processor that is looking for basic information about food freezing and cryogenics. It has been written in the language we use with our customers, using terms and concepts that are universally understood by the food processing industry.

We know that our customers live in a very real world ruled by Murphy's Law, dealing everyday with practical issues and concerns, dollars and common sense. They face capital budget constraints, inadequate floor space, overtime, safety issues and personnel problems, but they aren't allowed any excuses.

Our customers are plant engineers, business owners, complex managers, entrepreneurs, maintenance supervisors, line superintendents, purchasing agents, team leaders and operation managers. They are all the people that it takes to run a processing plant and our commitment to you is that if you come to us with a freezing or cooling project, we will find away to make your world a little easier to live in.

Second, this section is called Freezing Basics because it is just that... the basics. Use this section to get ideas or become familiar with freezing processes, but we urge you not to use it to specify a piece of freezing equipment.

There are many, many variables, and exceptions to every rule. Please pick our brains! Give us a call or send us a fax or an email.
Tell us about your product and processing requirements, and let us work with you to find the best solution. There are always several ways to get the job done, but usually only one BEST way. Whether we have a product to offer you or not, we'll give you the best advice we can. We strive to treat our customers the correct way while building lasting relationships that encourage the customer to return in the future. 

Freezing Basics:

There are many reasons why processors freeze their food products. Increasing shelf life, stabilizing the product, lengthening lines of distribution and satisfying customer convenience are just a few reasons why the frozen sections of our supermarkets continue to expand. At CES we know that when choosing a method to freeze his product, the producer must consider the economics of freezing, the impact on his processing operations, and the expectations and concerns of his customers. We are here to help you evaluate the facts so that you can find the right solution.

Food freezing can be classified in two very broad categories: Offline freezing and inline freezing.

Offline freezing refers to physically removing the food product from the production line in order to freeze it in a separate manufacturing step or location (such as a cold storage area or commercial blast freezer).

Inline freezing refers to a process that freezes products as part of the continuous manufacturing assembly line, so that products exit the assembly line frozen.

For the rest of this section, the systems we are describing are inline freezing systems.

Regardless of what you are freezing or chilling, you will need refrigeration. And refrigeration is a purchased product. Refrigeration can be mechanically produced (in which case you are buying electrical power and transforming that power into refrigeration). Alternatively, refrigeration can be purchased as a pre-cooled substance, such as liquid nitrogen (LN2) or liquid carbon dioxide (LCO2) and maintained in storage tanks. Freezing systems that use either of these refrigerants are generally referred to as being cryogenic* freezing systems.

*The National Institute of Standards and Technology has suggested that the term "cryogenics" be applied to temperatures below -238° F. However, correctly or incorrectly, the term " cryogenic freezing" is widely used in food processing to identify freezing systems using either liquid nitrogen (-320°F) or carbon dioxide (-108°F as a solid).

What Is Freezing Cost?

Refrigeration is a purchased product. However, it is only part of your freezing cost. Freezing cost is the total cost to freeze a product. Not every processor is going to measure freezing cost the same way, but the following are all components of the freezing cost equation:

Cost of Refrigeration: The cost of refrigeration or BTU's required to freeze the product expressed in cost per pound of product. If enough information is known about the product and proposed production parameters, CES can accurately project these costs during the equipment evaluation process. An existing system can be best calculated by looking at monthly refrigeration cost divided by pounds of production. For mechanical systems, this value is based on the cost of electrical power. For cryogenic systems, this is the cost of liquid nitrogen (expressed in either cubic feet or pounds) or liquid carbon dioxide (expressed in pounds) used in the freezing system.

Monthly Lease costs: The cost of a freezer system lease (either mechanical or cryogenic) and cryogen storage tanks should be taken into consideration.

Operating and Maintenance Cost: The total cost of operating the freezing system in freezer parts, downtime (such as defrost cycles for mechanical freezers), and maintenance man hours.

Production Cost: Some systems require an employee to either operate or monitor a freezer.

Lost Yield Cost: Some products are susceptible to dehydration damage during the mechanical freezing process. Not only can this lead to reduced product quality, but in some products this can also lead to yield losses as high as 6%. Cryogenic dehydration losses rarely measure over 1%.

Freezing Costs

Other Factors to Consider:

Product Market Life: Food products, especially new entries into the marketplace, have varied degrees of success and market life. Sometimes a leased cryogenic system is a low-risk means of introducing a new product to the market place, and is then converted to a mechanical system once the capital can be justified by known sales volume.

Plant Flexibility: Regardless of what kind of freezer is acquired, the larger the range of products it can produce, the more flexibility and capability the processor will acquire.

Turn-Up Capacity: Since processor needs can change so rapidly, a major consideration should be the ability of a freezing system to grow with a business

Don't be dismayed! CES can help with your evaluation process from the beginning. We have a wide range of practical data on the heat characteristics of food products, and we understand the economics and practical aspects of freezing all food products.

The first step in evaluating your options is to tell us about your product.

At CES we have the knowledge and resources to help you get the facts. We can help you calculate your heat load (the amount of energy or cryogen required), establish dwell time (the amount of time it takes to freeze the product), and size a freezing system accordingly. We can tell you how much it will cost to acquire equipment, install it, and your freezing cost. We know what works, and how to maximize yield and production performance. Our motive is to provide you with the best possible system for your process, and be your long term source for process and maintenance services and parts.