ert 426 food engineering semester 2 academic session 2010/11 bb lee @ unimap 1
TRANSCRIPT
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Introduction to Food Engineering
ERT 426 Food EngineeringSemester 2 Academic Session 2010/11
BB Lee @ UniMap
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Subtopics1. Background2. Food Industry in Malaysia3. Typical Food Manufacturing
Processes4. Recent Developments in Food
Engineering Research5. Present Trends and the Future of
Food Engineering6. Sociocultural Aspects of Some
Critical Points Limiting ProgressERT 426 Food Engineering BBLee@UniMAP
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1. BackgroundFood engineering is a
multidisciplinary field of applied physical sciences which combines science, microbiology, and engineering knowledge for food and related industries.
Food engineering includes, but is not limited to, the application of agricultural, chemical, mechanical, civil and electrical engineering principles in addition to food sciences to food materials. ERT 426 Food Engineering BBLee@UniMAP
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BackgroundFood Engineers:provide the technological knowledge transfer
essential to the cost-effective production and commercialization of food products and services.
• When foods are used as raw materials they offer unique challenges.
Perhaps the most important concern in food processing is the variability in the raw material.
To achieve consistency in the final quality of a processed food, the processes must be carefully designed to minimize variations caused by processing.
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BackgroundFood engineering is a very wide field of
activities.Prospective major employers for food
engineers include companies involved 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 hire food engineers.
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2. Food industry in MalaysiaMalaysia's food industry is as diverse as the
multi-cultures of Malaysia, with a wide range of processed food with Asian tastes.
In 2008, the food processing industry contributed about 10% of Malaysia's manufacturing output.Companies in this industry are predominantly
Malaysian-owned. In Malaysia, the food industry is dominated by
small and medium scale companies. The major sub-sectors are fish and fish
products, livestock and livestock products, fruits, vegetables and cocoa.
ERT 426 Food Engineering BBLee@UniMAP
Information is taken from Malaysian Industrial Development Authority (MIDA)
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Food industry in MalaysiaIt is estimated that the present global retail sales in
food products are worth around US$3.5 trillion, and are expected to grow at an annual rate of 4.8 per cent to US$6.4 trillion by 2020. Malaysia's food exports amounted to RM17.9
billion in 2008, while imports totalled RM28 billion.
Malaysia remains as a net importer of food.Malaysia exported food products to more than 200
countries. The main products exported were:
1. cocoa (RM3 billion), 2. fisheries products (RM 2.5 billion), 3. margarine and shortening (RM 2.4 billion) 4. animal feed (RM1.2 billion).
ERT 426 Food Engineering BBLee@UniMAP Information is taken from Malaysian Industrial Development Authority (MIDA)
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Food industry in MalaysiaMajor food imports in 2008 were cereal and
cereal preparations, cocoa, vegetables and fruits, dairy products and animal feed.
Raw materials such as cereals and dairy products will continue to be imported for further processing for human consumption as well as for the production of animal feed.
ERT 426 Food Engineering BBLee@UniMAP
Information is taken from Malaysian Industrial Development Authority (MIDA)
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Food industry in Malaysia
Currently, Malaysia is the largest cocoa processor in Asia and ranks fifth in the world. However, most of the cocoa beans are
imported. Malaysia is one of the world major
producers of spices.In 2008, Malaysia's was ranked as the fifth
largest exporter of pepper and pepper-related products (specialty pepper, processed pepper and pepper sauces).
ERT 426 Food Engineering BBLee@UniMAP
Information is taken from Malaysian Industrial Development Authority (MIDA)
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Food industry in MalaysiaThe halal industry in Malaysia provides
immense opportunities for Malaysian manufacturers.
With a global Muslim population of about 2 billion, the market for halal food is estimated at US$547 billion a year.
The concept of halal is associated with food products which are of high quality in terms of cleanliness, sanitation and compliance with religious requirements.
Local halal food products can gain easy access into world wide halal markets as Malaysia‘s halal certification is globally recognised.
ERT 426 Food Engineering BBLee@UniMAP Information is taken from MIDA
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3. Typical food manufacturing processesDuring the last 30
years, the food engineering discipline has evolved to encompass several aspects of food processing.
The diversity of processes typically employed in a food processing plant is illustrated in Figure 1.
ERT 426 Food Engineering BBLee@UniMAP (Heldman & Singh, 1981)
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Typical food manufacturing processesTypical food processes may include:i. sorting and size reduction, ii. transport of liquid foods in pipes, iii. heat transfer processes carried out using heat
exchangers,iv. separation processes using membranes, v. simultaneous heat and mass transfer
processes important in drying, and vi. processes that may involve a phase change
such as freezing.
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4. Recent Developments in Food Engineering ResearchResearch in food engineering was initially
focused on: the analysis of food manufacturing, the processing and packaging operations, the utilization of agricultural materials and
energy, the environmental issues.
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Recent Developments in Food Engineering Research
During the past two decades, however, chemical engineering and food engineering have shown a dramatic change in their research emphases because of revolutionary developments in three fields:1. Biotechnology particularly genetic engineering)2. Computer science and technology applied mathematics and modeling (e.g., kinetics,
neural networks, and fuzzy logic)3. Material science especially understanding the relations between the
molecular structure and functional properties of materials)
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5. Present Trends and the Future of Food Engineering
Paradigm for Product/Process Development in the 21st Century:
1. Development of key scientific "knowledge-based" components (e.g., food properties)
2. Development of quantitative relationships between food properties and quality attributes which should be:
• Quantifiable • Reproducible • Relevant
3. Relationships (models) organized in computer-based information systems similar to those available in the chemical industry for thermodynamic properties (e.g., Aspen).
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Present Trends and the Future of Food Engineering
4. Application of models in specific developmental tasks
5. Development and utilization of on-line sensing systems for key food properties (eventually similar sensing systems may be feasible for quality attributes as well).
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Present Trends and the Future of Food Engineering
Emulsification technology is important in the creation of mayonnaise, peanut butter, various full-fat and low-fat spreads, as well as many beverages and flavor preparations.
The rheological and diffusional properties of an emulsification process are of fundamental importance as new analytical and instrumental methods are available and mathematical relations relating them to process parameters can be established.
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Present Trends and the Future of Food EngineeringEmulsion Technology-Based Foods:1. Objectives of material science research:
Control of texture and mouthfeelControl of storage stability and thermal stabilityAbility to use alternative components to modify
nutritional and organoleptic properties2. Knowledge-based surface properties are :
Free surface energy, surface viscosity, dynamic tension, surface elasticity, surface charge
Rheological propertiesDiffusivity of components
3. Quantitative relational models have:Sensory response versus physical properties Physical properties versus temperature, pressure
and other variablesERT 426 Food Engineering BBLee@UniMAP
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Present Trends and the Future of Food Engineering
4. Applications:Low-fat spreads using fat mimeticsDesign of emulsification systemsIncorporation of controlled release formulations
5. Relevant new tools:Image analysis (visible, IR, NMR, ESM)Computer-aided simulation of structure New mathematical tools (e.g., fractal analysis)
6. Current status:The physical aspects have undergone advanced
research in key corporate and academic institutions
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Present Trends and the Future of Food EngineeringA useful way of presenting a material's physical
properties is with "State Diagrams," which can relate them (especially those related to molecular mobility) to temperature and aqueous system concentration.
One of their key features is a glass transition line that relates glass transition temperature (Tg) to the given solute's concentration.
Recent work at several research centers has developed information allowing construction of these diagrams for multisolute systems and food materials as well.
The knowledge of glass transition lines allows the prediction of conditions under which given desirable or undesirable changes are retarded or accelerated.
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State Diagram for food
materials
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Present Trends and the Future of Food EngineeringDeveloping Quantitative Relationships Between
Physical and Sensory Properties of Syrups:1. Mouth feel:
Sensory thickness is proportional to the shear stress on the surface of the tongue.
Sensory smoothness is inversely proportional to the friction force on the tongue.
2. Perception of properties during pouring: Subjective viscosity is related to the bottle-neck area filled by the
syrup. Subjective drippiness is related to the normalized instability growth
rate (which can be calculated from known physical parameters).
3. Perception of properties during spreading: Sensory viscosity shows a good correlation with the radial growth
of a syrup puddle. Sensory smoothness was well correlated with the aspect ratio of the
syrup mass. [Aspect ratio = Dmin IDmax , Dmin & Dmax - the minimum & maximum
diameters of a spreading puddle]ERT 426 Food Engineering BBLee@UniMAP
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Present Trends and the Future of Food Engineering
The use of enzymes that act specifically on selected substrates or intermediates to eliminate undesirable products or the localization of reactants, catalysts, or antioxidants in portions of food in which a particular reaction may be desirable (e.g., surface browning).
The requirement for the successful application of these principles lies in developing sound knowledge of the mechanism and kinetics of food reactions.
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Present Trends and the Future of Food Engineering
Potential Approaches for Controlling Complex Reactions in Foods:
1. Enzymes:Using substrate specificity of selected enzymes
reactions may be directed to produce desired products (e.g., lipoxidases to control oxidation derived compounds according to Vliegenthart of Utrecht and Pratt of Purdue).
Enzymes may also be added to remove undesirable products or intermediates.
2. Other catalysts or inhibitors:Reactions may be directed by catalyzing or
inhibiting specific reaction steps (e.g., pH control in browning reactions).
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Present Trends and the Future of Food Engineering
3. Addition of substrates or intermediates:Reactions may be modified by adding specific
precursors of desired end products.4. Localization of reactants or catalysts:As in liposomes containing proteases in
cheese ripening (Kirby)5. Controlling environmental factors:Different steps may have different activation
energies or reactants of differing solubility; regulating temperature, pressure, or water activity will control reactions.
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6. Sociocultural Aspects of Some Critical Points Limiting Progress
1. Reluctance of consumers to accept the following: Compositions perceived as unnatural (even
those that are natureidentical). Ingredients created or modified by genetic
engineering. Foods processed by nontraditional energy
input such as ionizing radiations.2. Inadequate public understanding of the
interface between diet and health resulting in temporary interests that often divert food product development from more sound long-term objectives.
ERT 426 Food Engineering BBLee@UniMAP