Further Links Contact Us Search Help

Syllabus | Exams | Assessment | Glossary | Site reviews | Careers

Food Technology

Home > Food Technology > Contemporary food issues - Nutrition > Controlling quality

Food Manufacture

Controlling quality

In the core, Food manufacture, you will learn about the quality and quantity control in the selection of raw materials for food processing. This tutorial focuses on the strategies used to control food quality.

Outcomes

This material addresses aspects of the following syllabus outcomes:

H1.1 A student explains manufacturing processes and technologies used in the production of food products.

Extract from Stage 6 Food Technology Syllabus Board of Studies NSW 1999.

When customers purchase mass produced food products they expect consistency in taste, texture, appearance and smell. Food companies need to ensure that the raw materials selected for food production produce desirable characteristics in the end product.

Food technologists are responsible for checking the quality of raw materials using scientifically valid experiments. The Riverina Environmental Education Centre web site http://www.reec.nsw.edu.au/geo/scient/text/rscc4.htm uses a case study approach to the manufacture of cracker biscuits, describing how raw materials, in this case, flour, are selected and tested. The experiments include:

In the first experiment, different types of flour are evaluated to determine which variety produces the most desirable characteristics of cracker biscuits.

This is followed up with simple experiments to investigate the freshness of self-raising flour, an important characteristic in the quality of raw materials used in baked flour products.

The final experiment compares the relationship between price and quality. Is the cheapest brand of flour able to perform as well as more expensive brands in producing quality end results?

The importance of having a control in producing valid data is emphasised in each experiment so that comparisons and conclusions can be made.

Testing the quality of raw materials

Testing the quality of raw materials which are then transformed into food products can be done in a number of ways:

Sampling involves tasting a number of similar products which have been prepared for uniformity. For some raw materials used in food production, sensory methods that use taste testing are impractical, however, when this method of quality control is implemented, serving temperatures, size, shape and colour of the food is important. The food tasting environment should be neutral and the same white serving dishes are preferred. Samples are coded and ranked by the judges according to the requirements of the food manufacturer.

Objective methods of evaluating the quality of raw materials depend on measures other than the human senses. They offer a permanent record of results, that can be reproduced and they are less likely to be subject to error.

Objective methods of evaluating raw materials include:

Chemical experiments, for example, determining the nutritive value of ingredients before preparation and after preparation.

Physiochemical experiments which analyse the chemical quality of raw materials that will influence their use in food products, for example, pH concentration or the hydrogenation of fats.

Microscopic examination which will influence the structure and properties of the final food product, for example, studying the microscopic qualities of cake batter could give valuable information as to its influence on the structure of the cooked cake.

Physical properties of raw materials such as temperature, length or amount of liquid drained from the food can be simple observable experiments that are frequently used.

Raw materials are transformed into food products in various ways: from adding or removing heat, water, air or micro organisms. In cooking, freezing, canning, drying, pasteurising and fermenting processes, the quality of the raw materials will have a significant effect on the final product.

Activity

1. Outline the desirable end characteristics for the following processed food products:
   • apple pie
   • cup of noodle soup
   • caramel syrup
   • tomato sauce
2. Why is comprehensive testing of commercial food products such an important aspect of quality control?
3. What role does food packaging play in maintaining the quality of raw materials?

Answers

1. Apple pie: crisp pastry, gold in colour, no fatty residue. Firm well packed filling, desirable apple flavour.
   Noodle soup: Flavoursome stock, soft noodle, visible ingredients.
   Caramel sauce: golden colour, absence of sugar crystals, pouring consistency.
   Tomato sauce: red colour, tomato flavour, smooth texture.
2. Consistency and food safety are important standards for food manufacturing. Consumers need to know that they will not suffer from food poisoning and that each time they purchase a food product it will taste and perform in the same way.
3. It should keep out vermin and insects, e.g. flour kept in paper and stored close to the ground is likely to become infested with insects.
   It should clearly identify the raw material so that confusion does not occur, e.g. salt can be mistaken for sugar.
   It should protect the raw material from heat, moisture and air, e.g. raw materials are often packaged then shrink wrapped to prevent damage from the environment, such as humidity or air.
   For more detailed information about packaging requirements visit the NSW Office of Fair Trading.