Introduction to Food Engineering

FOOD

Food is defined as anything solid or liquid which when swallowed, digested and
assimilated nourishes the body.

Foods are materials, in a raw, processed or formulated form, that are consumed orally
by humans or animals for growth, health and satisfaction or pleasure. Chemically, foods
are composed mainly of water, lipids, proteins, and carbohydrates with small
proportions of minerals and organic compounds. Minerals are salts, and organic
substances are vitamins, emulsifiers, acids, antioxidants, pigments, polyphenols,
flavors, etc.

FOOD SCIENCE

Food Science is the systematic study of the nature of food materials and the scientific
principles underlying their modification, preservation and spoilage.

It is the study of characteristics of foods including chemical, biochemical, physical,

physio chemical and biological properties and effect of these on the quality of the
product. It also covers application of this information in development of new products
and efficient processing techniques.

The textbook Food Science defines food science in simpler terms as "the application of
basic sciences and engineering to study the physical, chemical, and biochemical nature of foods
and the principles of food processing"

FOOD ENGINEERING

It is a multidisciplinary field which combines microbiology, applied physical sciences,

chemistry and engineering for food and related industries. Food engineering includes,
but is not limited to, the application of agricultural engineering, mechanical engineering
and chemical engineering principles to food materials.

Food engineers provide the technological knowledge transfer essential to the cost-
effective production and commercialization of food products and services. Physics,
chemistry, and mathematics are fundamental to understanding and engineering
products and operations in the food industry.
Food engineering encompasses a wide range of activities. Food engineers are employed
in food processing, food machinery, packaging, ingredient manufacturing,
instrumentation, and control. Firms that design and build food processing plants,
consulting firms, government agencies, pharmaceutical companies, and health-care
firms also employ food engineers. Specific food engineering activities include:

 drug/food products;
 design and installation of food/biological/pharmaceutical production
processes;
 design and operation of environmentally responsible waste treatment systems;
 marketing and technical support for manufacturing plants.

Typical topics include:

 Advances in classical unit operations in engineering applied to food

manufacturing
 Progresses in the transport and storage of liquid and solid foods
 Developments in heating, chilling and freezing of foods
 Advanced mass transfer in foods
 Advances in cleaning and sanitation
 Low moisture content foods
 New chemical and biochemical aspects of food engineering and the use of
kinetic analysis
 Process design and development of various alternative non-thermal food
preservation methods using lethal agents such as high pressure, pulsed electric
field, UV, ultrasound, ozone and cold plasma.
 New techniques in dehydration, thermal processing, extrusion, liquid food
concentration, membrane processes and applications of membranes in food
processing
 Shelf-life, electronic indicators in inventory management, and sustainable
technologies in food processing
 Modern packaging, cleaning, and sanitation technologies.
 Development of sensors systems for quality and safety assessment.

FOOD CHEMISTRY

It is the science that deals with the composition, structure and properties of food along
with the chemical reactions. It forms a major part of food science and is closely related
to food microbiology. Changes can be desirable and undesirable which can lead to
contamination of the food and further leads to food poisoning, food infection or just
spoiling and thus rendering it unfit for consumption.

Food chemistry is the study of chemical processes and interactions of all biological and
non-biological components of foods. The biological substances include such items as
meat, poultry, lettuce, beer, milk as examples.

It is similar to biochemistry in its main components such as carbohydrates, lipids, and

protein, but it also includes areas such as water, vitamins, minerals, enzymes, food
additives, flavors, and colors.

This discipline also encompasses how products change under certain food processing
techniques and ways either to enhance or to prevent them from happening. An example
of enhancing a process would be to encourage fermentation of dairy products with
microorganisms that convert lactose to lactic acid; an example of preventing a process
would be stopping the browning on the surface of freshly cut apples using lemon juice
or other acidulated water.

FOOD TECHNOLOGY

Food technology is a branch of food science that deals with the production processes
that make foods.

Food technology uses and exploits knowledge of Food Science and Food Engineering to
produce varied foods. Study of Food Technology gives in-depth knowledge of science
and technology, and develops skills for selection, storage, preservation, processing,
packaging, distribution of safe, nutritious, wholesome, desirable as well as affordable,
convenient foods. Another significant aspect of food technology is to save and utilize all
the food produced.

Developments in food technology have contributed greatly to the food supply and
have changed our world. Some of these developments are:

 Instantized Milk Powder: D.D. Peebles (U.S. patent 2,835,586) developed the
first instant milk powder, which has become the basis for a variety of new
products that are rehydratable. This process increases the surface area of the
powdered product by partially rehydrating spray-dried milk powder.
  Freeze-drying: The first application of freeze drying was most likely in the
pharmaceutical industry; however, a successful large-scale industrial application
of the process was the development of continuous freeze drying of coffee.
 High-Temperature Short Time Processing: These processes, for the most part,
are characterized by rapid heating and cooling, holding for a short time at a
relatively high temperature and filling aseptically into sterile containers.
 Decaffeination of Coffee and Tea: Decaffeinated coffee and tea was first
developed on a commercial basis in Europe around 1900. The process is
described in U.S. patent 897,763. Green coffee beans are treated with water, heat
and solvents to remove the caffeine from the beans.
 Process optimization: Food Technology now allows production of foods to be
more efficient, Oil saving technologies are now available on different forms.
Production methods and methodology have also become increasingly
sophisticated.

FOOD MICROBIOLOGY

Microbiology is the study of micro-organisms. They are very small, usually single celled
organisms which are not individually visible to the naked eye

Food microbiology is the study of the microorganisms that inhibit, create, or

contaminate food. This includes the study of microorganisms causing food spoilage; as
well as, pathogens that may cause disease especially if food is improperly cooked or
stored. Those used to produce fermented foods such as cheese, yogurt, bread, beer, and
wine. Then those researchers with other useful roles such as producing probiotics.

Microorganisms are of great significance to foods for the following reasons:

 Microorganisms can cause spoilage of foods,

 Microorganisms are used to manufacture a wide variety of food products, and
 Microbial diseases can be transmitted by foods.

UNIT OPERATION vs UNIT PROCESS

In unit operations only physical change takes place and no chemical change takes place
or we can say no chemical reaction takes place.

Evaporation, Distillation, Liquid liquid extraction, Drying, Size reduction,

Crystallization are the examples of unit operations. In these operations only physical
change takes place like phase will be change or two or more substances are separated
from each other or particle size will reduce. Their chemical structure is same as before
when they were sent for operation.

While in unit process only chemical reaction takes place. For example nitration,
sulfonation, oxidation, reduction of any compound.

PROSPECTS OF FOOD ENGINEERING

There are many lucrative positions open to food technologists like Quality Assurance
Manager, Laboratory Supervisor, Production Manager and food packaging manager.

Production Managers/Supervisors: They are responsible for the entire the processes in
the manufacturing of a product, right from the purchase of raw materials to the
production of the final product.

Quality Assurance Managers/Supervisors: They are responsible for ensuring the

quality of food throughout the whole production process. This includes the quality of
raw materials, equipment, finished goods, packaging, processing and storage
procedures.

Laboratory Supervisors/Technicians: They carry out or supervise quality tests, such as

microbiological and chemical analyses, before any product is released.

Food Packaging Managers/Technologists: They are responsible for the research and
development of new food packaging systems and filling equipment.

Research Scientists: They are responsible for the continuing research and development
programmes within the industry. Research scientists are employed in a wide variety of
projects with Government, Food Research Institutes and Food companies.

Product Development Managers/Technologists: They are responsible for the

improvement of the existing food products as well as for the development of new
products.

Lecturers and Advisers: They work in a range of posts in the Government sector and in
Universities, as college lecturers or in advisory and inspection jobs.

Food processing and equipment manufacturing organizations: Developing new

equipment and production methods
ROLE AND RESPONSIBILITIES

As a food technologist, you'll need to:

 modify existing products and processes and develop new ones

 check and improve safety and quality control procedures in your own and
suppliers' factories, from the raw material stage through to the finished product
 research current consumer markets and latest technologies to develop new
product concepts
 select raw materials and other ingredients from suppliers
 prepare product costing based on raw materials and manufacturing costs to
ensure profitable products
 audit suppliers or manage internal audits
 run trials of new products - either alongside or together with product
development
 coordinate launches of new products
 deal with any customer complaint investigations or product issues
 compile, check and approve product specifications and labelling
 undertake long-term projects with other departments, such as reducing waste by
improving efficiency
 work on packaging innovation and technology
 conduct experiments and produce sample products
 design the processes and machinery for making products with a consistent
flavor, color and texture in large quantities
 build relationships with suppliers and customers
 ensure products are profitable.

Depending on the sector you work in, you may also do the following additional tasks.

In food manufacturing:

 develop the ability to repeat processes to ensure consistency and safety

 liaise with technical and commercial colleagues in procurement, sales, technical
services and marketing and distribution, and with official food inspection and
hygiene agencies (this takes up a considerable proportion of time on the
manufacturing side)
 work with engineering and production to develop solutions to production issues,
while maintaining food safety.
In retailing:

 work with suppliers on quality issues and new product ideas

 manage the safety, legality and quality of food produced.

In the public sector:

 carry out administrative tasks and devise policy for government departments
 implement enforcement roles in local authority environmental health
departments.

SKILLS NEED TO SHOW

 Food science, food chemistry, microbiology, food processing, safety/ quality

assurance, good manufacturing practices and nutrition.
 Analysis of raw and cooked/manufactured foods for composition, quality and
safety.
 Food ingredients, their uses in food preparations and food production on a large
scale.
 Product specifications and food product development.
 Sensory evaluation and acceptability.
 Industrial practices, systems control, distribution channels, consumer purchase
patterns.
 Food packaging and labeling.
 Ability to use information technology to support product design.
 Carry out sensory evaluation.
 Skills in food preparation and cooking.
 Ability to design, analyse, follow a design brief and adapt recipes.
 A genuine interest in science and how it is applied to food and cookery
 High standards of cleanliness and the ability to adhere to strict hygiene rules
 Excellent attention to detail
 Strong written and verbal communication skills
 Leadership qualities
 People and team working skills
 A flexible approach to working
 Numeracy and problem-solving skills
 Time management and organisational skills
 An awareness of the consumer market.