FOOD ENGINEERING

CONCEPT

Agricultural Processing

A study that deals on the principles and practices of processing agricultural products suitable for food or feed

Food Engineering

A study that deals with the application of engineering principles of converting agricultural products into different kinds of food

Durable Crops

Crops produced and harvested with normally low moisture content of about 20% to 30% and are not easy to deteriorate or spoil.

Perishable Crops

Crops that have high moisture content (30% and above) such as fruits and vegetables including dairy, meat, and fish are easily to deteriorate and spoil

Primary Processing

Processing operation which does not heavily change the physical characteristics of the product. Drying and dehydration of grains and fruits are examples of this operation

Secondary Processing

processing operation which change the physical properties of the product. On-plant processing such as converting banana into catsup or mango to puree are examples of this operation

Tertiary Processing

These are industrial-scale processing that produces ready-to-eat (RTE), convenience foods, or highly processed products. Examples are canned goods, instant noodles, etc.

Gases

Compressible in nature and when compressed some gases change their state of matter

Liquids

Not highly compressible. They can be compressed into a very small degree only

Newtonian Fluid

Characterized by the rate of fluid shear that is linearly related to shear force

Non-Newtonian Fluid

The characteristics of fluid is not linear with the shear force

Streamlined Flow

Direction of motion of each element is parallel with the other element

Turbulent Flow

Fluid moves in elemental swirls or eddies

Reynold’s number

Ratio of inertial forces to viscous forces within a fluid serving as a predictor of whether the flow will be laminar or turbulent

Viscosity

The internal resistance of fluid to shear

Static Pressure

Pressure resulting from elevation and indicates forces perpendicular to the walls of a container

Dynamic Pressure

Pressure that results from force due to change in velocity of the fluid

Porosity

Indicates the percentage volume of spaces over the volume of the product plus the volume of the product plus the volume of the spaces within the product

Cono elliptical cylinder

The surface area of a product, especially paddy grain, is commonly regarded as having the shape of

Bulk Density

This is defined as the mass of the group of individual particles divided by the space occupied by the entire mass, including the air space

Particle Density

mass divided by the volume of the particle alone

True Density

density of the solid material excluding pores or void spaces

Angle of repose

The angle at which a product forms a conical pile from the horizontal after freely flowing from a discharge spout is called the __________

Angle of friction

Refers to the angle measured from the horizontal at which a product will start to move downward over a smooth surface.

Thermal conductivity

This material property indicates the amount of heat transfer from one side of the material to the other side by conduction

Specific heat

The amount of heat required to raise the temperature of a unit mass of a material by one degree Celsius

Coefficient of thermal expansion

The property that describes the change in volume of a material due to temperature change

Thermal Diffusivity

Measure of how quickly heat spreads through a material relative to its ability to store heat

Thermal Coefficient

General term describing how a material’s physical properties change with temperature, often related to thermal expansion and cracking behavior in materials like grains

Heat of Vaporization

Amount of heat required to convert a unit mass of a liquid (or moisture in a product) into vapor without changing temperature.

Process

It is defined as a set of actions in a specific sequence, to a specific end.

Unit operations

the actions that constitute a process called when they are grouped based on the same basic principles and similar purposes

Batch process

A process in which a portion of the materials to be processed is separated from the bulk and treated separately.

Continuous process

A process in which the materials pass through the system continuously, without separation of a part of the material from the bulk

Mixed process

A process that is composed of a sequence of continuous and batch processes

Flow charts

Shows the major operations of a process in their sequence, the raw materials, the products, and the by-products

Gels

Refers to a semirigid three-dimensional network formed by polymers trapping water

Emulsions

Refers to a mixture of two immiscible liquids where one is dispersed as droplets in the other

Foams

Refers to a structure consisting of gas bubbles trapped in liquid or solid walls

Powder

Refers to solid particulate materials typically ranging from 10–1000 μm in size

Pasteurization

This heat treatment aims to destroy all pathogenic microorganisms

Blanching

the process by which foods (usually fruits and vegetables) are briefly submerged in boiling water and then immediately cooled to stop further cooking.

Sterilization

A process that completely destroys all microorganisms in food, equipment, or materials through heat, chemicals, or other methods. (more than 100°C)

Filled milk

Refers to milk or cream reconstituted with fats from non dairy sources such as vegetable oils

Low-fat milk

Milk that typically contains around 1% milk fat

Whole milk

cow’s milk that contains no less than 3.25% milk fat by weight

2% milk

also known as reduced-fat milk, is a type of cow's milk that contains 2% milk fat by weight, making it a lighter option compared to whole milk.

Skim milk

also known as fat-free or nonfat milk.

Water activity

Measures available water for microbial growth.

Equilibrium moisture content

The property of grain that describes the moisture level it retains when exposed for a long period under a constant temperature and relative humidity condition is called __________.

Drying

The removal of excess moisture for safe storage.

Freeze drying

drying method is best for heat-sensitive foods like coffee

Powdered milk

Spray drying is commonly used for

Tray drying

a conventional drying method where wet solids are spread thinly on trays inside an oven, and hot air is passed over them to evaporate the liquid

Freeze drying

a dehydration process that removes water from a frozen product by converting it directly from ice to water vapor through sublimation, preserving the product's quality, texture, and nutrients.

Spray drying

an industrial process that atomizes a liquid or slurry into fine droplets, which are then rapidly dried by a hot gas (usually air) to form a dry, fine powder

Latent Heat of Vaporization

Refers to amount of energy required to convert a liquid into a gas without changing the substance's temperature

Latent Heat of Fusion

Refers to amount of energy required to convert solid into liquid without changing the substance's temperature

Radiation

Refers to the transfer of heat energy through electromagnetic waves without requiring direct contact

Conduction

The transfer of thermal energy from one material to another through direct physical contact between particles

Convection

The transfer of thermal energy caused by the movement or circulation of liquids or gases

Desorption

The condition in which the vapor pressure of the grain is greater than the vapor pressure of the surrounding air.

Direct-Fired

A type of burner where the flue gas and other products of combustion goes into the dryer

Indirect-Fired

A type of burner where the heat exchanger is used to prevent smoke and other products of combustion to go with the drying air

Preheating period

The stage of drying where very little moisture content change occurs because the heat is used to raise the grain temperature

Constant rate period

The stage of drying surface moisture evaporates continuously from the grain surface, allowing the amount of moisture removed to remain at its maximum, constant rate over time

Falling rate period

The stage of drying where moisture removal slows down because internal moisture takes longer to reach the grain surface.

First falling rate

Drying rate decreases due to reduction of wetted surface area

Second falling rate

Internal liquid diffusion controls the drying process, further reducing moisture removal rate

Tempering

The process of allowing the grain to rest in order for the moisture at the innermost portion of the kernel to equilibrate with the outer layer

Thin layer drying

Refers to the drying of a layer of grain that is only one kernel thick, allowing uniform exposure of all grains to the drying air

Material Handling

Term that pertains to the art and science involving the moving, packaging, and storing of substances in any form

Belt Conveyor

A type of conveyor that uses a continuous moving belt to transport materials from one point to another

Bucket Elevator

A material handling equipment designed to move bulk materials vertically using buckets attached to a belt or chain

Screw Conveyor

consists of a conveyor screw in a trough supported by end hanger bearings

Pneumatic Conveyor

Most common method of handling of large volume of gas is through pipes by the help of compressor, blower etc

100 m2

A processing plant is designed to handle 5 tons of commodity. What is the recommended minimum area for the processing plant?

2-5 processing days.

The storage area of a processing plant shall have a capacity for temporary storage of raw materials for _____

Bin

Refers to any vertical walled vessel used for storing solids.

Silo

Bins with height to diameter ratio > 1.5

Bunker

height to diameter < 1.5

Retaining

A silo that has an aspect ratio less than or equal to 0.4 (h/d ≤ 0.4) with a flat bottom

Intermediate

A silo that has an aspect ratio greater than 1.0 and less than 2.0. (1.0 < h/d < 2.0)

Mass Balance

Refers to the conservation of total mass in a process, where mass entering a system must equal mass leaving plus accumulation.

Material Balance

Focuses on tracking individual materials or components (water, sugar, fat, solids, etc.) throughout a food process to determine yields, compositions, and efficiencies

Energy Balance

Involves accounting for heat and energy entering and leaving a food processing system to analyze heating, cooling, drying, and refrigeration requirements.

Codex Alimentarius

or the “Food Code” is a collection of internationally adopted food standards and related texts presented in a uniform manner

Good Manufacturing Practice

A system that ensures that manufactured products—such as food, cosmetics, and pharmaceutical goods—are consistently produced and controlled according to set quality standards.

Hazard

A biological, chemical or physical agent in, or condition of, food with the potential to cause an adverse health effect.

Control point

Is a point, step, or procedure in a food process at which control should be applied so that a food safety hazard can be prevented, eliminated, or reduced to an acceptable level

Critical limits

Represents the boundaries that are used to ensure that a process step produces safe products.

Corrective actions

Any action to be taken when the results of monitoring at the CCP indicate a loss of control

Hazard Analysis and Critical Control Points (HACCP)

a preventive system to guarantee the safety of food for the consumer. It focuses on the prevention of physical, chemical and biological hazards rather than on carrying out inspection of the finished products

Sanitation Standard Operating Procedures (SSOP)

written procedures that an establishment develops and implements to prevent direct contamination or adulteration of product

Environmental Management Plan (EMP)

Consists of the set of mitigation, monitoring, and institutional measures to be taken during implementation and operation to eliminate adverse environmental and social impacts, offset them, or reduce them to acceptable levels.

International Organization for Standardization

What does the abbreviation “ISO” mean

ISO

stands for the International Organization for Standardization. It is an independent, non-governmental international organization that develops and publishes standards to ensure the quality, safety, efficiency and interoperability of products, services and systems across various industries

ISO 22000

What is the ISO standard number commonly associated with food safety management systems?