Food processing equipment is an umbrella term referring to the components, processing machines and systems used to handle, prepare, cook, store, and package food and food products. Although this equipment is primarily aimed toward the transformation—i.e., increasing the palatability, consumability, and digestibility—or preservation—i.e., extending the shelf life—of food, some pieces of equipment are also employed to perform preliminary or auxiliary functions, such as handling, preparation, and packaging.
Employed for food and food product applications ranging from bakery goods to beverages and dairy to produce, a wide range of food processing equipment is available to execute the various unit operations necessary during a complete production cycle, such as washing, separating, mixing, baking, freezing and sealing. Depending on the demands of the operation (and the overarching food processing application), this equipment can be designed and constructed to handle solid, semi-solid, or liquid food products by batch or continuously.
Some of the other design considerations include the food grade material used for construction, hygienic and governmental standards, sizing, cost and integration of automation or analytical components. Each of these characteristics can influence the performance and efficiency of the equipment but choosing the optimal design and construction is dependent on the specifications and requirements of the particular food processing application.
Types of Food Processing Equipment
The food processing production cycle can be broken into several stages, characterised by a specific function and during which individual unit operations are performed. For example, within the preparation stage, the primary function is to prepare the food material for further processing, and some of the unit operations performed include washing and separating. Other secondary functions provide support to the primary functions of the production cycle, such as material handling and system control operations which convey food materials between process stations or maintain the required processing conditions and standards, respectively.
Preparation Equipment:
As indicated previously, within the food processing production cycle, initial preparatory operations focus on preparing the raw food material for subsequent processes—typically mechanical or chemical processing—by separating the desirable material from the low quality, substandard, or undesirable material. In doing so, manufacturers are better able to ensure the production of uniform and high-quality food and food products, as well as remove foreign matter and contaminants which may degrade or damage the food material or equipment.
Some of the unit operations which manufacturers employ during the raw material preparation stage include cleaning, sorting, grading, or peeling (or skinning).
Mechanical Processing Equipment:
Mechanical processing operations are employed (without the application of heat or chemicals) to reduce, enlarge, homogenise, or otherwise change the physical form of solid, semi-solid, and liquid food matter. By altering the form and size of the food matter, manufacturers can facilitate and increase the efficiency and effectiveness of subsequent processes, improve the overall quality and edibility, and allow for a greater range of food products to be produced.
Within the general mechanical processing classifications—i.e., size reduction, size enlargement, homogenisation—there are numerous unit operations, such as cutting, forming, and grinding/crushing, which fall below them.
Heat Processing Equipment:
Depending on whether the application (and the specific unit operation) is aimed towards heating or cooling the food material, heat transfer equipment can be used to direct heat towards or away from the material, respectively. This section of the article will focus primarily on the applications and equipment aimed towards heating food products, while the following section—Preservation Equipment—will touch on the applications and equipment aimed towards cooling food products, as well as those intended to preserve and extend the shelf life of food products.
Heat processing equipment—i.e., equipment which heats food—can cause not only physical changes in the food material but chemical, biochemical, and biological changes as well. These changes can transform and affect the overall quality of the resulting food products—such as by altering the chemical structure or enhancing the flavour—and serve as a preservation method by inhibiting or destroying the microorganisms or enzymes which cause spoilage.
There are many unit operations employed during the heat processing stage, including blanching, baking, roasting, and frying.
Preservation Equipment:
As indicated above, many of the heat processing operations used in the food processing industry demonstrate preservative qualities. Although there is significant overlap between heat processing equipment and preservation equipment, the previous section already covers the former category—i.e., preservation methods (and their respective equipment) which apply heat. Therefore, this section will focus on other preservation methods, processes, and equipment.
The preservation stage of the food processing production cycle ultimately aims to prevent or inhibit the spoilage and increase the shelf life of food products. There is a wide range of preservation methods available ranging from refrigeration to irradiation, each of which acts to destroy microorganisms and enzymes within the food material or, at the very least, limit and depress their activity.
Packaging Equipment:
Following the preparation and processing stages, food material generally undergoes one or more post-processing operations, which help to produce the final food product and complete the food processing production cycle. While there are several post-processing operations involved with the production cycle, this section will focus on packaging operations and equipment.
Food Packaging can serve several functions, including:
Containment: Holds (i.e., contains) food contents until they are used
Protection and Preservation: Creates a physical barrier between processed food products and physical, chemical, microbial, and macrobial variables during storage, transportation, and distribution which can cause spoilage, contamination, or loss of quality
Convenience: Enables food products to be portioned out (by weight or volume) for easier consumer use, and stored, transported, and distributed
Communication: Helps identify the food contents and indicate handling, storage, and use instructions, as well as allows for an opportunity for branding and marketing
Additionally, food packaging is available in several forms—e.g., boxes, jars, bottles, cans, etc. Depending on the packaging form used to package the food material, packaging operations, and the equipment employed to execute them, can significantly vary. Some of the other factors which may influence the type of packaging equipment employed include the type and form of food product and the storage, handling, distribution, and marketing requirements.
Food Quality Measurement Instruments
An important aspect of food processing and food preparation is the topic of food quality control. Food quality in a production setting can be degraded and compromised by any number of contributing factors, the most common of which include the presence of :
Pesticides
Pathogens
Heavy metals
Organic toxins
Foreign objects
In addition to these factors, food quality needs to be validated in terms of nutritional content and consistency, be assessed for the presence of allergens, verified with respect to adulteration and certification for GMO, and tested for shelf life.
There are a number of instruments used in food laboratories that can be applied to assure food quality which applies to solids as well as beverages. Some of the most common examples of these instruments and their use are described below.
Alcoholic beverage analysers – Can be used to measure the alcohol content, density, color, and pH of alcoholic beverages.
Carbonated beverage analysers – measure product density, temperature, current/fresh/inverted sugar concentrations, degree of inversion, and CO2 levels.
Food analysis equipment – various instruments that can be used to measure the fat, protein, and oil concentrations in food samples and detect the level of gluten in foods.
Pesticide detection instruments – detects the presence of pesticides in food samples.
Electron Spin Resonance Spectrometers – also known as electron paramagnetic resonance (EPR), these instruments can be used to test the purity of products without physically destroying or altering samples.
Cell and colony counters – can be used to measure the colonies of microorganisms that have grown on an agar plate prepared from a sample.
Incubators – are used to provide a controlled environment (i.e. temperature, humidity, CO2 level) for food safety testing.
Chemical imaging (NIR/Raman) systems – devices that use analysis of samples by detecting and analysing light that is in the near-infrared, visible, or near-ultraviolet light areas of the electromagnetic spectrum.
Magnetic analysers – detect low levels of iron in food samples by measuring the imbalance in resonance between two air core coils which can be translated into a signal that reflects the level of iron present in the sample.
Moisture analysers – also known as moisture balances, these devices are used to establish the percentage of moisture in a food sample, either by weighing the sample before and after an evaporation process or by using an absorption spectrometer to analyse the gas emitted during evaporation to establish its content.
Polarimeters – devices that pass polarized light through a sample and measure the angle at which the emitted light emerges. Optically active substances will cause a change in the polarization angle of the emitted light, which can be used to establish concentrations of sugars such as glucose and sucrose.
Refractometers – are devices that measure the angle of refraction from light that is passed through a liquid, gel, or solid substance and using that to establish parameters such as the salinity and sugar content.
Rheometers and Viscometers – are instruments that can measure the viscosity of a fluid and the behaviour of fluids when shear or stress forces are applied to it. Having this information can reveal the properties of the fluid that relate to its structure and elasticity.
Saccharimeters – are instruments that specifically measure the concentration of sugars present in a solution. They do so by measuring the refractive index of the liquid as light as passed through it.
Titration Equipment – can be used to detect and measure the concentration of a substance within a liquid through acid/base titration. The addition of titrant of known concentration to a known volume of solution with unknown concentration can determine that unknown concentration through a reaction neutralisation.
Other equipment – additional equipment often employed in food quality applications includes ovens, centrifuges, water baths, and dry baths.
Additional Equipment
Beyond the aforementioned equipment, there are other types of auxiliary equipment that may not directly contribute to the various food processing stages but are still critical to the food and processing industries and their operations. This equipment can serve or support several functions throughout the overall production cycle, including:
Utilities: Utility equipment provides the resources necessary for operating and maintaining a food processing facility, such as pumps, generators, power supplies, and combustion equipment. Typical resources include electricity, heat, water, steam, compressed air, and waste disposal options.
Measurement and Control: Measurement and control equipment is used to ensure that the food processing equipment operates correctly, and the food processing stages proceed as specified. These instruments can be used to analyse ingredients and machines, as well as allow manufacturers to perform and duplicate processing procedures. They can also be used to monitor existing systems and machinery, such as logging data during product testing or quantifying typical performance statistics. Measurement devices are particularly crucial during food production, as minor changes in cooking temperature, ingredient ratios, and operation times can lead to drastic changes in the finished product. Some of the measurement and control devices commonly used for food processing include:
Precision controls
Pressure gauges
Scales and weighing systems
Thermometers
Timers
Material Handling: Material handling equipment is used to transport food material through and between preparation, processing, and post-processing stations. Types of equipment used for material handling in the food and food processing industries include:
Conveyors system
Fluid transport devices (e.g., pumps, hoses, tubes, and piping)
Storage: Storage equipment allows food material to be held between processing stages (or operations), and the final food product to be stowed and warehoused prior to distribution. Food and food products can be stored by a variety of methods depending on the type of food being stored, the length of storage (i.e., short-term or long-term) and the storage requirements, and include:
Bags, bins, boxes, and silos (i.e., types of storage containers for solids)
Tanks, vats, and vessels (i.e., types of storage containers for liquids)
Cold storage rooms (for chilled or frozen products)
Product Distribution: Distribution equipment prepares and packs completed food products for transportation to their final destination (generally a store or other type of marketplace). Smaller packaged food products are typically grouped and packed together prior to transportation to optimise efficiency, while larger packaged food products can be wrapped and shipped individually on pallets.
Equipment Cleaning: Regular cleaning and sanitation operations are essential to maintaining the hygienic environment required for food processing. Food processing equipment is often designed to help optimize these operations with components assembled such that can be cleaned after dismantling or via cleaning in place (CIP) methods. Cleaning and sanitation equipment used for food processing applications includes:
Cleaning in place systems
Ball spray devices (for process and storage tanks)
Dry steam vapour cleaners (for food processors and beverage equipment equipment)
Design and Selection Considerations for Food Processing Equipment
As outlined above, there is a wide range of food processing equipment available to satisfy the various functions which are integral to the food and food processing industries. While individual pieces of equipment may have some distinctive considerations—typically based on the specific functions and unit operations which they perform—to keep in mind when designing and selecting equipment for a particular food processing application, there are also a few factors an industry professional or procurement agent can consider across the board to ensure that their food processing equipment fulfils their needs. These factors include:
Function
Form
Hygienic design
Sizing
Construction requirements
Operational characteristics
Cost
Function
The particular function for which a piece of equipment is intended largely determines the general type of equipment employed. For example:
Material handling equipment includes conveyors and tube systems
Preparation equipment includes sterilisers or wash systems
Heat processing equipment includes ovens and fryers
Preservation equipment includes freezers and dehydrators
Product distribution equipment includes wrapping and palletising systems
Form
The form in which the food material being processed comes in significantly influences the specific type of equipment employed as some food processing equipment is better suited for one form over another. For example, among material handling equipment, pumps are better suited for transporting liquid food material, while conveyors are better suited for transporting solid food material.
Hygienic Design
As the products produced by the food and food processing industries are intended for consumption, the equipment employed to execute the necessary processes and unit operations is designed with consideration to hygiene and sanitation standards and regulations set by a variety of government agencies and private organisations. These standards and regulations outline the requirements and best practices aimed towards ensuring the manufacture of safe food and protection of public health and safety. For example, industrial professionals must select not only appropriate food-grade materials but design and construct the equipment such that the risk of contamination and food quality degradation is minimized and the methods of cleaning and sanitizing are optimised.
Sizing
There are several factors which help determine the optimal size for food processing equipment, but ultimately, the goal is to balance the material and resources used for each unit operation and the required production output. Typically, processing equipment is oversized between 10–20 per cent to compensate for potential operational issues, such as equipment breakdown or demand fluctuation, or environmental conditions, such as temperature or humidity changes. However, depending on the production requirements of the particular facility, multiple, small-sized equipment can also be employed to allow for greater operational flexibility.
Construction Requirements
As indicated above, food processing equipment must be constructed with consideration to hygienic design. Beyond this requirement, equipment must also be designed and built to withstand the stress from the various mechanical, chemical, thermal, and physical processes and unit operations of the food processing cycle. Other construction requirements to keep in mind include:
Dimensional and weight restrictions
Facilitation of cleaning and maintenance operations
Use of standard vs. custom parts
Operational Characteristics
Food processing equipment is typically designed and built with a particular function or unit operation in mind. However, the method in which these functions and operations are executed can vary depending on the design of the equipment, and additional components can be integrated to facilitate smoother operation. Some characteristics of food processing equipment to consider include:
Batch vs. continuous processing
Manual vs. automatic operation
Integration of analytical or quality control units Integration of ergonomic or safety components
(The author is head chef at Health By Mondo. He can be reached at healthbymondo@gmail.com)