Manufacturing Techniques for the Home
Depending on whether a food product is being made at home or in the industry, different manufacturing techniques are used. The table below highlights examples of these differences when making a cherry bakewell tart.
Assembling raw ingredients Computerised machinery Assembling raw ingredients Each
to accurately weigh each component component added, weighing on scales
Mixing Large scale mixers used Mixing Domestic equipment used
Cutting Industrial cutters used to slice accurately Cutting Knife used to cut blocks
Slicing Large scale slicers used to slice accurately Slicing Sharp knife used
Glazing Spray guns used to release the glaze evenly Glazing Pastry brush and jug with egg
Piping Large scale machine used controlling the Piping Piping bag and nozzle filled
amount of mixture to be piped with icing
Cost is a very important factor to consider when designing products for manufature and sale; the product must make a profit to be viable.The process of costing a product is a balancing act. The following costs must be taken into consideration:
- Set up and initial design ideas
- Factory and distribution
- Marketing and advertising
- Retailer's cost and profit
The breakdown of costs is:
- Ingredients - 30%
- Labour - 5%
- Packaging - 5%
- Factory and distribution - 20%
- Marketing and advertising - 10%
- Retailers cost and profit - 30%
When deciding on a price for a product the following factors need to be considered:
- The target market - how much would they be willing to spend on the product?
- The price of similar products on the market
- Where it is going to be sold
If the product is overpriced it may not sell so the market limits the price manufactuers can put on the product
Food packaging needs to fulfil the following criteria:
- Protect the food product from damage in transportation and storage
- Keep bacteria and dirt away from the food
- Attract consumers to look at and hopefully buy the product
- Increase the shelf life of the product
- Contain the food product
- Provide the consumer with information about the product
- Discourage tampering with the product and make tampering evident
Some packaging also needs to be:
- A good heat conductor to enable reheating
- Suitable for microwaving
Labelling on food packaging informs and advises the consumer. For manufactuers it is legal requirement to include the following on a food label:
- The name of the product
- The ingredients
- The net weight
- The name and address of the manufacturer
- The 'use by' or 'best before' date
- The storage instructions
Scaling Up Recipes
Scaling up is a term used in the food industry which means that small-scale recipes are increased for factory production. The amount of each ingredient is increased but the proportions of each ingredient stay the same. Scaling up should not affect the quality of a product.
When scaling up recipes for large scale production in industry, food technologists must also consider adding ingredients to maintain flavour, texture, colour and the shelf life of a product. Small batches are produced to see whether production in quantity affects the sensory characteristics of the product. After testing, modifications may have to be made to the product. The food technologist also has to consider large scale mixing and baking temperatures, and the effect these may have on whether the product meets the specification. The calculations for scaling up are carried out by a computer which calculates the percentage of each ingredient in the original recipe.
A specification is used to ensure that the product being manufacturered is suitable for the intended market or user group. Food technologists produce a design specification first. This is then developed into a more detailed product specification, and type of food materials and the production processes chosen for the food product depend on it. A manufacturing specification is developed from this for large scale food production.
The following should be included in a specification:
- Target group
- Nutritional requirements
- Retail price
- Method of production
- Method of reheating
- Colour and Labelling
- Garnish and Safety
- Appearance and Quality
Manufacturers might modify an existing product for the following reasons:
- To adapt a recipe for larger/smaller scale productions
- To extend the product range
- To respond to lifestyle changes
- To create new products ideas
- To respond to what the competition is developing
- To enhance the qualities of an existing product
- To increase or maintain sales of a product when its life cycle is coming to an end
- To meet the needs of the user group
Primary Foods and Primary Processing
Primary foods include milk, meat, fish, eggs, wheat, vegetables, fruit, maize, vegetable oils/fats
Simple primary processes can be achieved by:
- washing or cleaning vegetables or salad plants
- peeling fruit or vegetables
More complex primary processing is achieved by:
- producing flour from wheat
- pasteurising milk
Simple tasks such as peeling, chopping, slicing and grating are all primary processes. They produce ingredients that can be combined and assembled with other ingredients to produce sweet or savoury products. These primary processes ensure that the food products will be edibe and safe to eat. Futher primary processing carried out on primary foods converts them into secondary foods e.g. milk>cheese, wheat>bread
Secondary Processing and Cutting
Secondary Processing using large pieces of electrical equipment can change the shape and size of raw materials by:
Large scale equipment is used to cut, slice, mince and grate very large quantities of food materials. This process is often computerised to achieve consistent results. Mechanical cutters are also used in the initial stages of cheese making.
Large electrical graters are used in the production of grated cheese for use as a standard component for the food industry. Standard components are ready prepared ingredients and are used during the manufacture of food products.
Shaping and Moulding
Pasta and biscuits are a good example of a mixture being cut into shape or extruded into a variety of different shapes. Extrusion is when a mixture such as a biscuit dough is passed through a series of pipes which gives the finished shape to biscuits before cooking. Pasta dough can also be extruded to give the different shapes avaliable on the supermarket shelves
Moulding is a technique used with pastry to produce different shapes and sizes for flan cases and pipes etc
Functional properties are the qualities a food ingredient possesses. Starch particles found in wheat flour can thicken a mixture when mixed with a liquid and heated.
Addition of raw egg may bind dry ingredients in place. Eggs are useful ingredients to food maufacturers because they have the ability to coagulate on heating and are an important ingredient when making:
- egg custards
- quiche fillings
- cake mixtures
- meringue cases
Food technologists need to know how these foods react when combined so that they obtain the best possible results
Composites have recieved more complex processing and can be used in different ways to make different products. They can be made cheaply in large quantities and are quick and easy to use for both the consumer and the food industry. Composites are parts of a recipe that come ready prepared to the food manufacturer
In order to ensure successful results in a food product it is important to understand how the properties of food react with the following:
- Other ingredients
Setting, fermentation, fortifiation, tenderising, laminating, shotening, aeration, browning, crystalisation, foaming and solutions are all different functional properties of foods used in manufacturing
In order for some ingredients to set into a firmer, more pliable texture gelling agents are used in food preparation to set liquids. Gelling agents are used to:
- Create a smooth set texture
- Set meat or fish in a savoury jelly
- Stabilse (prevent separation) which ensures a smooth consistency
Examples of gelling agents include gelatine, pectin, rennet and commercial additives. Gelatine is prepared commercially from bones and tissues of animals and is sold in powdered or sheet form. It is used to set jellies and mousses. It does not set some fresh fruit juices because they are too acidic and the mixture remains a liquid. There is a vegetarian alternative which is made from seeweed. Pectin is found in different amounts in fruits e.g. strawberries contain very small amounts and lemon juice is needed to set strawberry jam. Pectin can also be prepared commercially and is avaliable in liquid or powdered form. Rennet sets milk during the production of cheese making. Rennet is an enzyme found in the lining of a calf's stomach, it is used in a dilute form. There is a vegetarian source of rennet made from vegetables and used in cheeses which are labelled 'suitable for vegetarians'. Commercial additives are manufactured gelling agents extracted from natural substances such as beans, seaweed, plants etc. and used in the following products: - Instant desserts - Meringues - Spray cream - Low calorie spreads
Fermentation and Fortification
Fermentation is used in wine/beer making, bread making and pickling. It is biological process and involves a series of chemical reactions.
Fortification is when food products are enriched with vitamins and minerals to compensate for the loss during manufacture and to make the nutritive value of the product similar to the original ingredients. The following table shows how some foods are fortified:
Food Fortified nutrient
Fruit juice Vitamin C
Textured vegetable protein Iron and vitamin B complex
Margarine and low fat spreads Vitamins A and D
White bread and flour Vitamins B1, B3, iron, calcium carbonate
Yoghurt Vitamins A and D
Tenderising and Laminating
Tenderising meat ensures that the meat is palatable and easily digested. Tenderising breaks down the tissue and tough muscles which makes the meat more tender. This can be done by:
- Mechanical techniques
- Marinating. This softens the tissues as well as adding flavour
- Ageing is used mainly for game meat
- Hanging meat causes the connective tissue and the muscles to loosen which makes the meat more tender
Laminating is a process which adds another layer to a food product. It adds colour, texture and flavour as well as nutritive value.
Shortening and Aeration
Shortening is the addition of a pure fat in order to make short crust pastry and biscuits crumbly and 'short'. The correct proportion of fat is important to achieve good results. Too little fat will make tough pastry; too much fat will make the pastry difficult to handle and taste unpleasant.
Aeration produces a light, open textured mixture and can be achieved by mechanical techniques such as sieving, beating, whisking, creaming or folding. Chemical techniques can also be used. These involve the reaction of a chemical agent with an ingredient in a mixture in order to produce carbon dioxide which expands and raises the mixture when heated. Chemical raising agents which produce carbon dioxide include biocarbonate of soda, baking powder and yeast. Steam can also be used to aerate a mixture providing there is sufficient liquid in the mixture which heats up, evaporates and turns into steam which in turn raises the mixture. Steam is used to aerate mixtures in batters.
Browning is an important process in food manufacture because colour and appearance affect the consumers' decision whether to buy the food product. Making products the right colour is an important aspect of product development. Knowledge of what causes colour changes in food must be applied when designing and making food products. There are four causes of browning:
- Non-enzymic browning happens when a carbohydrate reacts with a protein in the same food. This produces a more appetising product which smells good, has a good flavour and a brown colour
- Enzymic browning occurs when fruits such as apples, bananas and pears are peeled and cut and exposed to the air. Substances in the fruits react with the oxygen and turn the cut surfaces brown which is unattractive to the consumer. Adding an acid such as lemon juice to the cut can prevent this.
- Caramelisation occurs when heating sugar to a temperature above its melting point which in time gives a pleasant toffee-like flavour as well as turning brown. OVerheating will burn the sugar and the flavour is very unplesant. Carmelisation is used in toffee apples and créme brulee. It is crunchy and sweet to taste.
- Dextrinisation occurs when starch is turned into dextrin during dry cooking.
Crystallisation and Foaming
Crystallisation is water and sugar in a solution used in the manufacture of confectionary. Because the temperature is raised to above boiling point the water evaporates leaving a higher level of sugar which forms crystals
Foaming provides structure, an open texture and lightness to a product such as meringues and soufflés. It is achieved by whisking egg whites into a foam and folding it into a mixture to make mousses. It is important to know that egg yolks contain fat which can prevent a foam working if the yolk is present when whisking egg whites
Shelf Life and Fats/Oils
Fresh food cannot be kept indefinately and in time it will decay, deteriorate and no longer be safe to eat. Food manufacturers have to ensure that products remain at their best during production, storage and until they are consumed.
Food manufacturers enhance the shelf life of a product such as bread, cakes, biscuits, soups and sauces by adding fats/oils, sugar or chemical preservatives
Fats and oils are sometimes added to food products to improve the shelf life and enhance texture, flavour and nutritive value. There is a wide range of fats/oils avaliable and they are used extensively by food manufactures for a variety of reasons. They have the following properties:
- Melt on heating - Do not mix with water - Contain vitamins A and D - Retain moisture in a cake mixture which helps to prolong shelf life - Have good shortening properties - Give flavour to fried or baked products - Give colour to fried/roasted foods
Sugar is a useful commodity, it is a sweetener, a preservative and an energy giver. Sugar is used in sweet and savoury products such as tomato sauce, baked beans etc. Sugar is useful because it:
- Dissolves readily in water, especially hot water
- Can be heated to high temperatures and caramelises which acts as a colour and flavour enhancer
- Sweetens food products
- Can help aerate mixtures with the help of fat in a cake mixture
- Attracts water and therefore prevents the drying out of cakes so will prolong shelf life
- Can act as a preservative in jams and jellies
- Can add texture to a food product
Food manufacturers often use chemical additives which help to keep food safe to eat for longer. Adding chemical additives makes it possible to store food longer at home and for food to e avaliable out of season. Sugar and vinegar are classed as additives and have been used for centuries to preserve food. Preservatives (E200s) protect food against the action of microbes, extend shelf lif and are used in foods like cured meats, cheeses, salad creams etc. Antioxidants (E300s) prevent fats going rancid, protect fat-soluble vitamins and prevent fruit and vegetable browning. They are found in fruit drinks, vegetable oils, low fat spreads and stock cubes. Emulsifiers and stabilisers (E400s) form an emulsion between oils and water and prevent separtion on storage
Food products can be improved in quality, flavour and nutritional value by the addition of other ingredients. This is called enriching and food manufacturers often enrich products to improve the nutritional profile or to replace the nutrients lost during processing. Fibre, iron and vitamins are added to promote 'healthy foods'. Vitamins A and D are added to margarine by law. Eggs, cheese and pulses can also enrich food products by adding proteins and other nutrients. Eggs can enrich food products such as cakes/ pastries, mashed potato, custards, sauce and yeast doughs. Cheese can enrich food products such as quiches, scones, pizzas, sauces. Pulses such as peas, beans and lentils are a good source of NSP (non starch polysaccharide) as well as energy and the B group of vitamins. Pulses are useful ingredients to manufactures because they can enrich foods cheaply by adding lentils to soups etc
Physical Finishing Processes
To make food products look more attractive and appetising food manufactures use a variety of physical finishing processes which include glazing, icing, colouring, piping and garnishing. Glazing is a finishing process which adds a smooth and shiny surface to either a sweet or savoury product. A glaze can also add colour and texture:
-Milk can be brushed onto scones/pastries -Beaten egg used to give shiny glaze on scones/pies -Sugar and water gives a sweet sticky layer on danish pastries/chelsea buns -Warmed jam can be brushed onto flans/cakes -Quick gels can be added to fruit flans -Aspic jelly can be added to pork pies
Icing can be used to attract children and adults to food. Icings can imprve the appearance and flavour of a sweet product. Some icings can be of a consistence which is suitable for piping onto a cake. Piping is also used to create patterns on savoury products. Garnishing is the process of adding another ingredient to make a dish look more attractive. It can also add nutritive value such as:
- Sliced hard boild egg on kedgeree
- Sliced tomatoes on a quiche
- Chopped parsley on a fish pie
Carried out by food maunfacturera to see if a new product meets the needs of the product specification and to provide information for the product label. Nutritional analysis of a new product takes place after the recipe has been developed. Then the product is put through a factory trial run where a batch is made under the same conditions that the final products would be in. Portion sizes are tesed in a laboratory for nutritional content. If the nutrients have been lost then the following procedures can be undertaken:
- The recipe can be modified and the product fortified
- More vitamins, minerals and additives can be added
- The recipe can be altered so that certain claims can be made about the product
This process is called a nutritional profile
By law some nutritional information must appear on the packaging. Nutritional analysis is carried out to ensure correct information is on the food label. This is an essential stage of food manufacture.
Essential in the development of a new product, it is a scientific measurement of the quality of the food being developed. A taste panel from the development team carry out the sensory analysis tests to check the taste, texture, appearance and smell of the food product. These sensory tests have to meet the needs of the consumer so they will enjoy eating the product and will buy it again. Panels of testers are trained so that they understand the meanings of the words being used to describe the qualities of the food. Using this format willl mean the results are accurate and reliable. In industry sensory analysis can be carried out as a team disscussion to ensure the changes being made are an improvement or it can take place in individual booths. The conditions for undertaking individual sensory analysis must be:
-Hygenic -Well lit -Free from smells -Quiet -A glass of water should be provided to clean the palate -There should be no outside influences or comments
The food samples should be randomly labelled and be the same size. This method of testing ensures accurate results which can be used by the food manufacturers to adapt new products and modify existing ones. If the results are unsatisfactory the product will be modified and a new taste panel will evaluate and assess the product. Some foods cannot be tested because the presence of micro-organisms and they rely on technical specification for good quality products
There are a variety of sensory tests that are used by food manufacturers to carry out the analysis of a food product. The type of test used depends on what the manufacturer wants to find out. The different types of test can be divided into:
-Difference tests -Ranking tests -Rating tests -Star profiles
Sensory Tests- Difference Tests
Are used when an ingredient or a process has been changed or when comparing a competitor's product. The difference tests are:
-Paired Comparison Test: This is when a taste panel tests two samples of the same food in order to find out if there is a difference between them in relation to one specific quality e.g. Comparing the moistness of a fruit cake with that of a competitor's fruit cake.
-Duo-Trio Test: This test uses three samples, two of which are the same. The taste panel is told one of the identical samples and they are asked to select the sample that is differnt from the other two. This is a useful test when testing a modified version of a low fat product for example against the original product to see if they have similar sensory characteristics.
-Triangle Test: This test uses three samples, two of which are the same. However, the testers are not told which two are identical and they are asked to select the sample that is different from the other two. This is a useful test when the difference between products is very small
Sensory Tests- Ranking and Rating Tests and Star P
Ranking Tests -In ranking tests the taste panel are asked to put the samples in order of preference (hedonic ranking). Symbols are usually used so that the tester is not influenced by product names. The testers may be asked to rank the samples according to the strength of a particular characteristic, e.g. how salty it is.
Rating Tests -Rating tests have been designed to find out how much someone like or dislikes a product. A scale is used with discriptors (a hedonic scale). There can be up to nine identified points on the scale ranging from like extremely to dislike extremely. An odd number of points is always used because the mid-point is needed to obtain more realistic results.
Star Profiles -Star profiles are used to describe the exact taste, texture and appearance of food products. Several sensory characteristics can be compared at the same time and the results are used to write a product profile. A star profile is a diagram drawn in a star shape with marks from 0-5 on each line. Each line is labelled with a characteristic. The food is tested and the results are plotted on the star diagram, the marks are then joined together. This gives a detailed at a glance profile of the product.
Quality of Manufacture
In spite of all the sophisticated machinery avaliable to food manufactures there is still difficulty in getting every batch of a product identical. The product specification makes allowances for variations in the desired weight, temperature, colour and size. This variation is called tolerance level and is shown by a plus (+) or minus (-) at either side of the target value. If the product weight is within the tolerance level then the manufacturer knows the final product will be of the required quality.
In the food industry large scale computer operated machinery is used to make sure each item or portion is the same size and shape and has the same quantity of ingredients as all the others.
Computerised weighing machines are used to weigh out ingredients accurately, electronic scales are also used. Random samples of a food product are removed from the production line at any stage in the process and weighed. The weight is recorded every 20 minutes.
If the tolerance level is exceeded, either by too much or too little, then the product is rejected.
Planning For Production
Quality asserance is the assurance given by the manufacturer to ensure high quality products that fulfil all the requirements of the product specification. It is the responsibility of every member of the design and manufacturing team to follow the guidelines of quality assurance because it is about improving, maintaining and promoting a quality food product.
Quality assurance involves:
- Documentation is needed to record everything that is happening at each stage of production
- Daily records are kept of all the processes at each stage of production
- Identity numbers are provided for all raw ingredients
Quality assurance ensures a product will meet the requirements of the specification in all areas including:
-Appearance -Flavour -Size -Finish -Shape -Price -Chemical and micro-biological standards
Planning For Production 2
Quality control is part of the quality assurance procedure. The main function of quality control is to make sure the food is safe to eat.
Quality control is a snapshot of what is happening during the production process at any moment. Checks are regularly carried out during production to ensure the specifications are met. Inspection and testing are practical ways in which quality control is applied.
Quality control checks include:
- Visual checks- checking food and packaging passing on the conveyor belt
- Sensory testing- check food ingredients
- Chemical analysis- samples taken and analysised for nutritional content/contamination
- Micro-biological analysis- samples are tested for bacteria
- Weight- tested at the packaging stage, the computer set to rejet anything below set weight to make sure the product is consistant
- Temperature checks- made at various stages.
- Metal detectors- often computerised and at end of production line. Dectors reject any faulty packages.
By law commercial food must be safe to eat. Bacteria can infect easily and food manufacturers must comply with Health and Safety regulation and prevent food comtamination.
By law all food handlers must be trained in Health and Safety requirements. Food handlers have to understand why personal hygiene and protective clothing are necessary.
Food poisoning can easily happen when bacteria infect food from:
- Dirty equipment/tools - Incorrect food preparation
- Pests (flies, vermin) - Poor timings of cooking and chilling
- Dirty food areas - Inaccurate temperatures for cooking/
- Incorrect food storage refrigeration/ serving
- Foreign objects e.g. jewelery in food - Poor standards of serving foods
- Poor personal hygine habits - Disinfectants from cleaning materials
Food safety 2
Employers are required by law to provide safe working conditions for employees. All surfaces and equipment must be easy to clean and regularly disinfected. To prevent contamination, equipment and tools are thoroughly cleaned and sterilised aftereach production run. Swabs are taken from work surfaces to check for bacterial contamination. Industrial premises must be free from pest infection and a pest control policy must be in place.
Meat, fish, cream, eggs and soft cheeses are known as high risk foods. They are likely to contain food poisoning bacteria and should be storedat below 8 C to reduce the risk of the bacteria multiplying. In food factories all foods are checked by quality control and if accepted the high risk foods are stored in refrigerators at 5 C, and frozen foods at -18 C. Separate refrigerators must be used for different foods to prevent cross contamination e.g. raw food is stored separately from cooked food.
Hazards and Risk Assessment
A hazard is anything that may cause harm to a consumer. There are three kinds of hazard:
- Physical e.g. mice droppings, glass in food
- Biological e.g. bacteria, moulds
- Chemical e.g. disinfectants, cleaning materials
Food manufacturers have to identify levels of risk at each stage of production. They must identify:
- The risk of a hazard happening
- The seriouslness of the risk e.g. food poisoning
- Ways of preventing, reducing or eliminating the hazard
The analysis is Risk Assessment
Food Safety Systems
HACCP (Hazard Analysis and Critical Control Points) is a food safety system used in all stages of production. The critical control point at which a hazard could occur and where action must be taken to eliminate the risk. All food maunfacturers have HACCP in place to ensure the safety of their products.
The production area is a food plant is divided into low and high risk areas. Low risk areas are where the ingredients are handled before being processed. The high risk area is known as the clean area, this is where the ingredients are processed. Once food has passed into the high risk area it is never sent back into the low risk area to avoid contamination.
Food handlers will work in either the low risk area or the high risk area, never both, and they must wear protective clothing all the time when on the production line. PPC (Personal Protective Clothing) consists of the following:
- Hair nets - Clean aprons
- Hats - Plastic gloves
- Clean overalls - Plastic overshoes
Use of ICT in the Food Industry
Using a computer speeds up the time it takes to carry out many tasks . ICT is increasingly being used by the food industry in the design process to:
- Identify needs - Develop detailed specifications
- Develop production ideas from the specification - Communicate product ideas
- Produce detailed work schedules
When identifying needs the Internet is useful for researching food issues from the Food Standards Agency website and visiting the websites of supermarkets such as Tesco/Sainsburys. E-mail is useful if you need to send design ideas to potential customers or manufacturers for advice. It can also be very useful when promoting a new product.
ICT has many other uses within the food industry. Spreadsheets are used for recording and analysising results from questionnaires etc. Clipart packages are useful for providing images suitable for labels and packaging. Specifications can be drawn up using a word processor and saved on disk and opened when modifications to the product are required.
CD-ROMS produced by the British Nutrition Foundation include up to date information. They can help: with nutritional requirements, modifying recipes, analysing results, and researching recipes
Using CAD in the Food Industry and Domestic Use
In Food Industry
Computer aided design (CAD) can help with the design of new product ideas, new shapes and patterns and colours. All the design ideas can be modelled using a food modelling program; the ingredients are input and the program will model the final product without the actual product having to be made. Food modelling programs can be used to modify a food product by changing the ingredients or by altering the proportions of the ingredients.
Digital cameras are useful in the food industry. They provide a visual record of the original and modified product. A digital image of the original product could be altered in a CAD package to show the effect of changing the colour or shape of the product.
In the home small scale is now used regularly include:
-Microwave ovens - Bread makers -Timers -Deep fat fryers
These pieces of equipment have similar benefits to those used in the food industry:
- Save time - Help ensure consistent results -Ensure good quality
Microwaves ovens are good examples of CAM because they have computerised programming facilities and are suitable for one-off products. The advantages of using a microwave oven are:
- Speed and ease of defrosting
- Speed of cooking and reheating
- Different settings for different foods
- More accurate cooking temperatures and time control
Features of the more updated microwave ovens include the following:
- Computerised touch pads which operate the oven. Instructions are provided on the screen.
- Weight sensors which weigh the food so the program can automatically calculate the cooking time required.
- The oven automatically reheats and cooks chilled food when you enter the weight
Timers and Bread Makers
Computerised timers are used in the food industry. They ensure that each stage of the process is exactly the same length of time; this is need for consistent results.
Bread makers are good examples of small scale use of CAM. The advantage of a bread maker is that the machine does all the work that is traditionally done by hand. New features of modern bread makers include the following:
- Automatic programming so that the bread can be made at any time in the day
- A digital timer can be pre-set up to 13 hours ahead of time
- Touch control panel for simple programming
Deep fat fryers
The main feature of a computerised deep fat fryer is safety. The computer controlled program can set the length of cooking time and the temperature of the fat/oil depending on the type of food being fried. The deep fat fryer is an enclosed unit which is an added safety feature.
One off production
One off production is used to produce highly skilful products made to the customer's own specification. Highly skilled craftspeople use general purpose tools and equipment. Products made in this way are very expensive in relation to similar products that have been batch or high volume produced because they take large amount of time to complete.
Examples of one off products are:
- Wedding cakes
- Birthday cakes
- Iced chocolate eggs
- Foods designed for special occasions
Batch production is used when a fixed number of products are required. This process will involve the use of specialised machinery and the different stages in the process are combined in a production line. All machinery in the production line is cleaned between each production run.
The cost of batch materials is more economic than one off production because greater volumes of ingredients are needed and these can be bought more cheaply in bulk. Also, automation means that fewer, less skilled workers are required.
Products made in batch production include:
- Fruit and meat pies
High Volume Production
High volume or continuous flow is a process that uses a highly efficient machine. Identical products are produced continously 24 hours a day, seven days a week. The machinery is kept running without stopping unless there is a breakdown, a problem with the products or essential cleaning is required.
High volume or continuous flow may be used for the following products:
- Frozen peas - Breakfast cereals - Margarine and spreads
- Bread - Crisps
Only a small workforce is needed to maintain the continuous flow process because the processes are automated. The operatives may not come into contact with food at all; they are there to maintain the correct running of the machines.
The scale of production determines the size of the manufacturing plant and the kind of machinery within it. Food manufacturing plants can range from a small local bakery to very large factories. The systems in these food plants are often computer controlled to maintain quality. Large scale machinery is often specially designed for a specific task. Some of the specialised equipment only have one task and therefore the cost is high. Products which are in high demand are made with this type of machinery.
Advantages of ICT
An effective computer system is advantageous to the food manufacturing process for the following reasons:
- It provides efficiency in the processes and systems as well as in managing the workforce
- It provides a faster product time to market
- It can help reduce/control waste
- It is cost effective (can lower costs)
- It provides information and feedback
- It monitors quality
- It enables consistency and high quality products to be produced
Uses of ICT in food manufacture
Computers are used at every stage in the production process:
- Market research and analysis
- Design and packaging
- Nutritional analysis
- Product and process modelling
- Manufacturing processes, e.g. automated production lines
- Bacterial modelling
- Control systems during production: -weight sensors -temperature controls
- Food storage
- Stock control
- Bar codes
- E.P.O.S (Electronic point of sale)
Databases and Electronic Data Interchange
Databases are a means of storing every detail about a food product. A database will include information about the following:
- Raw materials - Pre-manufactured components - Recipes - Specification
- Costings - Quality control data - Date and time of delivery of ingredients
- Source of ingredients - Visual check records
If a problem occurs every member of the production team will have access to this information and be able to resolve the problem
Electronic Data Interchange
Electronic Data Interchange (EDI) is a computerised system which provides up-to-date information about the orders coming into the food manufacturer from the distribution centre. Orders can change for many reasons such as:
-The season of the year dicgating the demand of a particular product -Promotional activities having an impact on expected sales
Manufacturing need to know this information to enable them to adjust their products.
The Internet and Electronic Point of Sale
E-mail and the Internet are electronic links which make the exchange and gathering of information faster and easier that before. The Internet includes up-to-date information on food related topics such as:
-Recent food laws -Health and safety information -Recipes -Consumer issues
Home shopping can now be done on the Internet; a customer can place an order to the supermarket and the order will be delivered at a convenient time to the customer
Electronic point of sale (EPOS) is a system used at checkouts in supermarkets and is valuable at gathering information. Every product has a different unique barcode.
When the barcode is scanned the name and price are provided and the product is itemised on the reciept.
All this information is transmitted to a File Maintenance Depot (FMD) which records the daily sales and enables the supermarket to monitor stock. The FMD updates the stock levels overnight, and this information is transmitted to the distribution depots who then re-order stock as required to deliver it to the store.
Food Micromodel is a computer software program used in the food industry to model bacterial growth in food products. It can also predict ways in which food spoilage bacteria will grow under certain conditions.
Recipes and formulations can be analysed micro-biologically, so that it is then possible to model the effect of changes in formulation and to design safety into a product.
Computer aided design (CAD) is used in the food industry for designing and making packages. The product and its packaging can be modelled in 2D and 3D. Using CAD enables different colours and images to be tried out on screen ti find the most appropiate design.
2D modelling is used for designing nets in the food industry. A net is a 2D shape but when cut out and folded it becomes 3D packaging. The information about the net profle can be transmitted from the computer ti a card cutting machine. In industry the net profile is multiplied many times and the computer is able to plan the nets in such a way that maximises the use of the paperboard as economically as possible. All the artwork and information about the food product will have been included into the paperboard before the manufacture of the packages.
3D 'Virtual Reality' computer soft ware is used to create food products on screen. The product can be viewed from all angles and this helps in the development of a new product. 3D modelling saves time, materials and money needed to make prototype products for batch and volume production
Computer aided manufacture (CAM) is used to help manufacture, monitor and control the automatic production of food products. Electronic sensors monitor changes in food and this information is fed back to the computers so that problems can be sorted out by the machine operatives.
Sensors used in the food industry test for the following:
- weight changes
- temperature changes in mixers, ovens, cooling ovens and freezing units
- changes in food colour
- tolerance levels for weight and dimensions
- moisure content
- humidity of cooling ovens
Meeting the specific needs of a food manufacturer is the task of the designer of CAM systems who work with food manufactuers to develop computer programs best suited for specific needs which contain fast, accurate and repeatable production properties.
Computer numerical control (CNC) means controlling machines using numbers and digital information. The machines needed for this system are highly sohpisticated and very expensive to set up. These machines are used for fast, repeatable and accurate production processes.
CAM systems use CNC machinery to carry out tasks in the production processes. CAD software can be used to drive CNC machinery
The benefits of CNC include:
- increased speed and accuracy
- increased flexibility as they can be used in batch and high volume products
- continuous operations
- economical to operate
An example if CNC machinery is a robot which is a piece of equipment that is computer driven and mimics the skills of a human being. Robots are used for 'pick and place' operations and are designed to perform specific functions such as gripping small, hot, fragile or soft components, packing biscuits into trays or stacking boxes of food product.
Computer integrated manufacture (CIM) is a system in which all stages in a food production process are integrated and controlled by computer systems. The computers are linked together in a network which controls the machinery and flow of information during the manufacturing process.
High volume product such as bread, cereals and snack foods use CIM systems. CIM systems are essential for high volume products for the following reasons:
- produce high volume of products quickly
- are highly accurate for repeatable processes
- always produce a consistent result
Effects of Technology on Society
Technology affects society and our everyday lives. Developments in technology have the following advantages:
- save labour, time and energy in industry and the home
- increased product reliablitiy and safety standards
- they have led to products being more consistent in quality and sensory characteristics
- help the food industry to produce cheap food
- give the consumer a wider and more varied choice of products. E.g. through increased oppotunities for food import due to better transport, storage and packaging; through the development of modern food materials and processes; and through the use of biotechnology
Synthetic flavours are easy to create and cheaper than using natural flavours. They are used in yoghurts, almond essence, low fat products, soups and sauces to increase the shelf life and quality of food products
Modified starch (starch treated with acid or alkali) forms a gel with cold water or milk. It is used in instant desserts, mouses, toppings, sauces, soups and gravies
Antioxidants are added to food products to prolong the shelf life. They prevent fruit and vegetables from turning brown and they inhibit the oxidation of fats, which can make fatty foods like oily fish turn rancid
Biotechnology is not new; yeast is a living organism that has been used for centuries to interact with flour, water, sugar and heat to make bread rise. This is a biological process. Cheese making is another example of biotechnology; the reaction of rennet with milk to produce curds and whey employs the activities of an enzyme. Other examples of biotechnology include the production of yoghurt, salami, vinegar, and pickles.
Biotechnology also involves the breeding of plants and animals to improve desirable characteristics. Genetic modification (GM) is the altering of genes to produce new characteristics. The benefits of GM include:
- It can make food crops resistant to pests and diseases
- It can control weeds during crop production
- It can increase the quantity (yield) and quality of food produced
- It can improve the nutritional value of foods
Genetic modification raises both ethical and safety issues. E.g do people have the right to interfere with nature in this way? are GM foods safe to eat?
The production of micro-protein (Quorn) is an exellent example of how biotechnology has brought new products to the market. It's a good source of protein, low in fat/chloesterol and high in NSP. It can now be bought in many forms: chilled/frozen, chunks, mince, fillets
The Management of GM Food Development
GM foods raise several moral issues:
- Are GM foods safe to eat? There are strict controls on the production of GM foods but we don't know the long term effects of eating them.
- Should all GM products be labelled to show that the food contains genetically modified genes could 'escape' and transfer across species which would have unknown results.
The Fair Trade Foundation has its own label, which is only awarded to Third World companies that give their producers a fair deal. By purchasing Fair Trade products you will be contributing to improved living, health and financial conditions in less economically developed countries.
Condition for animals in factory farms are often cramped with poor ventilation, limited lighting and no room for the animal to exercise or move freely. Disease and infection can spread easily in the crowded conditions
Moral Issues 2
Selective breeding produces faster growing chickens, hens that lay more eggs and cows that produce more milk. The effects of this type of breeding on animals raise moral issues.
Many consumers are concerned about the, as yet, unknown side effects of irrdiating food and would prefer not to eat foodstuffs that have been irradiated. There is also concern that irradiation affects the nutritional content of some foods. The symbol opposite is found on the packaging of foods that have bee irradiated.
Different cultures and religions have specific food requirements:
- Jewish faith- food must be kosher and dairy foods and meat kept totally separte
- Hindus- don't eat beef, mainly vegetarians
- Muslims- no pork or shellfish and only halal meat
Lacto-vegetarian- will eat milk and cheese, not meat, poulty, fish and eggs
Ovo-Lacto-vegetarian- will eat milk, chese and eggs, not meat, poutry or fish
Vegans- will eat only plants and will not consume any food that is of animal origin
Vegetarians need alternative sources of iron such as pulses, green vegetables and cereals. They also need alternative sources of vitamin B12 such as fortified breakfast cereals and yeast extract. Vegans can find alternative protien in Quorn, textured vegetable protien, soya, cereals and pulses.
In order to support sustainability, food manufacturers need to find ways of achieving the following:
- Using more energy-efficient processes and reducing the consumption of resources like water.
- Using sustainable resources e.g. recycling or using renewable resources like softwoods
- Reducing waste and using by-products of food production
- Using processing techniques and preservation methods to avoid waste, prolong shelf life and preserve food suppies
Food packaging affects the enviroment in two ways:
- resources are needed to produce packaging - packaging disposal create pollution
Recycling, redesigning and reducing the amount of packaging is the key to reducing the impact on the enviroment
Environmental Issues 2
Glass: Recycling glass uses less energy than creating new glass
Metal foils and cans: Aluminium and tin cans can be recycled indefinately and can be reformed into food containers
Paper and card: Paper and card can be recycled five times before the paper fibres weaken, although recycled paper is often of a lower standard than virgin paper
Plastics: Making new plastics results in using oil and gas which leads to air pollution
It is difficult to recycle packaging made from mixed materials because it is difficult to separate out the different layers. Packaging designers need to consider using materials that can be easily recycled or materials that have already been recycled. It is then up to consumers to make sure that packaging is actually recycled and not just thrown away.
Designers are redesigning packaging by: - reducing the amount of packaging used - developing effecienctly shaped packaging and refillable packaging
Environmental Issues 3
Food manufacturers can help to protect the enviroment by redesigning their production processes. By selling the by-products that result from producing a food product, waste can be drastically reduced.
Computerised control systems can improve efficiency. Accurate measuring and controlling processes can help to reduce waste and energy costs. Automating labour intensive processes using CIM and robots can reduce labour costs, reduce human error and speed up the processing time.
Food technologists analyse food products to give them ideas for new products. Product analysis involves several activities:
- Disassembly- taking a product apart, reading the labels, tasting it and evaluating attributes such as the way it is made, its ingredients and specification
- Research- finding out how a product is made and finding out what consumers think of it
- Evaluation- assessing the product quality, its enviromental impact, and any moral or cultural attributes
Product analysis helps designers understand how other products are produced. It also helps with the design of new products and can help to design efficient production processes. Product analysis helps manufacturers produce products that will sell successfully and ensures that products are of good quality and are safe to eat. Product analysis helps consumers select the product that is right for them. The following list gives a range of criteria that may be used when assessing a food product: -product description -target market group -function -ingredients -product data -production methods -packaging -safety issues -texture -flavour/aroma -appearance -freshness -value for money -user perceptions -moral values -enviromental issues -cultural issues
Planning involves setting out a sequence of the activities involved in the production process. A process or system can be broken down into three main stages:
- Inputs- i.e. raw ingredients, workers, machinery
- Processes- i.e. assembling, mixing, processing, cooking, cooling, packaging
- Outputs- i.e. the finished product, storage before transportation to outlets
Control and Feedback
A system will also have control and feedback built into it, e.g. making cheese involves control of temperature, time, hygiene, quality of the ingredients and the activity of the bacteria. When planning a system, the food technologist must make sure that it includes these controls.
A system may contain many sub-systems. The system therefore needs to include a process that monitors and controls the heating and cooling of the product (milk). The sub-system ensures that milk is heated to the correct temperature and will feed back information on the temperature of the milk and the speed of the rapid cooling process. Manufacturers often use components for sub-systems that monitor, control and feedback information.
Controlling the temperature if pasteurisation is important because at 71.7 C harmful bacteria are destroyed. It is therefore vital for health and safety reasons that the temperature is controlled. Food technologists identify these critical control points (CCPs) and ensure there is a sub-system in place to eliminate, reduce or monitor a hazard.
Quality of Design and Manufacture
The following checks are made at CCPs in order to maintain the quality of desogn and manufacture of food products:
- Quality control- checks are carried out throughout the production process by specialist machinery and by the production worker to ensure the design criteria are satified during product manufacture.
- Raw Material Checks- all raw ingredients will be checked prior to entering the manufacturing area.
- Weight Checks- the weight of the ingredients, the weight of the product at various stages will be checked. Cooking temperatures are monitored and controlled in cpmputer-controlled oven tunnels. The core temperatures of food products is tested with a temperature probe.
- Time Checks- computers will control the cooking and cooling times of products.
- Metal Detection- if there is the smallest trace of metal the detector will identify it, setting off an alarm.
- Micro-biological Testing- sample products are sent to independent micro- biological testing laboratories
- Other check- in addition to the above check, manufacturers may use sensors that can check a product's humidity, moisture content, size, shape and consistency of colour