UGRC 145: FOOD AND NUTRITION IN EVERYDAY LIFE

Transcription

1 UGRC 145: FOOD AND NUTRITION IN EVERYDAY LIFE SESSION 13 - TRADITIONAL FOOD PROCESSING Lecturer: PROF. MATILDA STEINER-ASIEDU, SBS, CBAS; University of Ghana, tillysteiner@gmail.com College of Education School of Continuing and Distance Education 2014/ /2017

2 Session Overview Learning Objectives: At the end of this lecture you should be able to: identify some technologies used in food processing and preservation to describe some traditional technologies used in food processing and preservation (Ghana). explain the effects of food processing on the nutritional value of food list examples of traditionally processed foods in Ghana and the processing technology employed Prof M. Steiner-Asiedu Slide 2

3 Session Outline Topic One: Introduction Topic Two: Why Food Processing Topic Three: Traditional Food Preservation Methods Topic Four: Other Industrial Processes Prof M. Steiner-Asiedu Slide 3

4 Topic One: INTRODUCTION Prof M. Steiner-Asiedu Slide 4

5 Introduction The following factors have put pressure on the world s food supply: Population growth Climate change Seed for growth quality Soil quality And many others Can you think of a few? Prof M. Steiner-Asiedu Slide 5

6 Introduction Cont d Other challenges to food supply are sustainable affordable food supply demand for specific foods stability in food supplies accessibility Achieving access to food by all people at all times in the right amount and quality remains a global challenge to ending world hunger Prof M. Steiner-Asiedu Slide 6

7 Improving food supply This can be achieved through Food production: this has to do with agricultural technologies Food processing: this has to do with prolonging shelve life of foods and transforming raw foods into different forms or new food products. Prof M. Steiner-Asiedu Slide 7

8 Improving food supply Cont d The field of science and technology have been used for thousands of years to help provide adequate food. This have been possible because of knowledge and new techniques gained from research investigations attempts to increase efficiency reduce environmental impact on production competition between large scale food companies Springing up of traditional or local food companies consumer demand and preference Prof M. Steiner-Asiedu Slide 8

9 Improving food supply Cont d It is important to note that innovation in food production processing new product development can offer benefits for consumers and the environment Prof M. Steiner-Asiedu Slide 9

10 Topic Two: WHY FOOD PROCESSING Prof M. Steiner-Asiedu Slide 10

11 Why food Processing The progression from hunter-gatherer to agriculture led to the need to store and preserve foods Abundant harvest Without some form of processing, foods deteriorate rapidly due to the action of microorganisms and enzymes. Prof M. Steiner-Asiedu Slide 11

12 Why food Processing Cont d Extend shelf life Maintain sensory properties Maintain or improve nutritive properties Ensure safety Make more convenient To increase digestibility, nutritive and health value To attract & satisfy the consumers, to develop the food market To preserve foods To maintain or enhance the quality Bottom line: $$ (economic value) Slide 12 Prof M. Steiner-Asiedu

13 Processing and Preservation Use of chemicals such as acid, sugar and salt: Examples: Vegetables pickling in vinegar (ACID) Salting meat or fish (SALT) Jam making (SUGAR) Use of Temperature control Examples Sun drying of fruit, pepper, cassava Ice blocks to preserve fish, meat, fruits Prof M. Steiner-Asiedu Slide 13

14 Common preservation techniques used in Ghana Freezing: (0 C) -Change in water from liquid to solid. This will reduce spoilage by making water unavailable for microorganisms and chemical reactions. (Fresh foods - fruits and vegetables, meat, poultry, fish, dough, minimally processed vegetables, pasteurized dairy products) DRYING: Probably oldest and most widely used form of food preservation. Reducing the amount of free water will prevent microbial and chemical spoilage Examples: sun/solar drying, hot air drying oven Prof M. Steiner-Asiedu Slide 14

15 Common preservation techniques used in Ghana FERMENTATION: Use of microorganisms to convert foods (raw commodities) into a more stable form by reducing the ph of the food or produce substances which make the environment uninhabitable by other organisms - acid or alcohol, some antimicrobial compounds (Cheese, Yogurt, Wine, beer, Sauerkraut, Pickles, Vinegar, Soy sauce) Prof M. Steiner-Asiedu Slide 15

16 What is Preservation? Prof M. Steiner-Asiedu Slide 16

17 Food Quality Prof M. Steiner-Asiedu Slide 17

18 Other reasons for Food Processing To make sure food is safe Destruction of toxins To improving properties of food that people desire in food. These include Physical and chemical Sensory (taste, texture, flavour) Aesthetic (appearance and look) Prof M. Steiner-Asiedu Slide 18

19 Topic Three: TRADITIONAL FOOD PRESERVATION METHODS Prof M. Steiner-Asiedu Slide 19

20 Introduction These include Drying and dehydration Smoking Salting Fermentation Prof M. Steiner-Asiedu Slide 20

21 Sun Drying This is the oldest methods of food preservation in Ghana and other developing countries. Common food dried are fruits, vegetables, roots and tubers, legumes, fish and meat. It is best to dry on raised plat forms to avoid contamination The open air drying also has the disadvantage of contamination from insects, dirt, rodents, and birds. To avoid contamination solar driers are best and they also offer good temperatures for drying and minimize damage to nutrients such as vitamins. Prof M. Steiner-Asiedu Slide 21

22 Smoking This is commonly used for fish and meat. Smoke contains chemicals which come from the burning wood and help to preserve the product. The heat produced help to dry up the product and thus prolong the shelf life. Important to note that not all wood is good for smoking fish or meat since some contain chemicals that are toxic Prof M. Steiner-Asiedu Slide 22

23 Salting This is the oldest most common method and food flavouring method. Two common processes are used Brine salting or pickling (Pig feet, Dry salting (koobi) Gives special flavour that most people like Prof M. Steiner-Asiedu Slide 23

24 Fermentation This method depends on the use of microorganisms to produce chemical and physical changes which alter the appearance, body and flavour of the original food material. Examples of foods that used this method are: Gari Corn dough Cassava dough Dawadawa Momoni (Stink Fish) SEE HANDOUT FOR DETAILS Prof M. Steiner-Asiedu Slide 24

25 Topic Four: OTHER INDUSTRIAL PROCESSES Prof M. Steiner-Asiedu Slide 25

26 Food fortification Fortification involves the addition of nutrients to foods irrespective of whether or not the nutrients were originally present in the food. Preseason fro fortification replace nutrients lost during food processing nutrients are sometimes added to produce a substitute product with similar nutritive value Enrich product by adding extra nutrients that would not normally be there e.g. added fibre in yogurt, folic acid in breakfast cereals. Prof M. Steiner-Asiedu Slide 26

27 Conclusion Food processing Essential for human well-being and health Influenced by the state of the society Driven by consumer demand Understanding of the connection between food, nutrition and health is key eating well and making right food choices. Prof M. Steiner-Asiedu Slide 27

28 REVISION MAKE SURE YOU READ HANDOUT 11 TO SUM UP EVERYTHING FOR YOU. GOOD LUCK Prof M. Steiner-Asiedu Slide 28

29 UGRC 145: Food and Nutrition in Everyday Life IT HAS BEEN A JOY INTERACTING WITH YOU. THANK YOU!!!! Prof M. Steiner-Asiedu Slide 29