1. Food processing is the use of suitable methods and techniques to transform raw edible substances into food for human consumption

2. The purpose of food processing are to :a) Prevent microorganisms (e.g. bacteria and mold) from putrefying or fermenting

food b) Prevent oxidation from spoiling food c) Extend the shelf life of foodd) Make food looked better and tastiere) Remove toxinsf) Prevent excess food from spoiling and going to wasteg) Produce different varieties from a single food substance , for instance milk is

processed into cheese, milk powder, butter and yogurth) Enable easy food distribution to consumers i) Increase food consistency for marketing

3. A short history of food processinga) When prehistoric humans first discovered fire, they processed food by cooking

it (burning, baking over hot stones and boiling) and later smoking it.b) Then they leave meat, fruits and vegetable in the sun and wind to remove their

moisture c) Much later, people discovered the salting of fish, meat and vegetablesd) Today, we use some of these main methods to process our food like canning,

drying, dehydration, freezing (first commercial use in 1842), freeze-drying, pasteurization, fermentation or pickling and irradiation

a) Pasteurization1 Pasteurization is a process which slows microbial growth in food. The process was

named after its creator, French chemist and microbiologist Louis Pasteur. The first pasteurization test was completed by Louis Pasteur and Claude Bernard on April, 1862. The process was originally conceived as a way of preventing wine and beer from souring.

2 Unlike sterilization, inventor Nicolas Appert, pasteurization is not intended to kill all pathogenic micro-organisms in the food or liquid. Instead, pasteurization aims to reduce the number of viable pathogens so they are unlikely to cause disease (assuming the pasteurization product is refrigerated and consumed before its expiration date). Commercial-scale sterilization of food is not common because it adversely affects the taste and quality of the product. Certain food products are processed to achieve the state of commercial sterility.

3 Pasteurization typically uses temperatures below boiling since at temperatures above the boiling point for milk, casein, micelles will irreversibly aggregate (or "curdle"). There are two main types of pasteurization used today: High temperature /short time HTST and Extended Shelf Life (ESL) treatment. Ultra High Temperature (UHT or ultra-heat treated) is also used for milk treatment Pasteurization methods are usually standardized and controlled by national food safety agencies. These agencies require milk to be HTST pasteurized in order to qualify for the "pasteurization" label. There are different standards for different dairy products, depending on the fat content and the intended usage. For example, the pasteurization standards for cream differ from the standards for fluid milk, and the standards for pasteurizing cheese are designed to preserve the phosphates enzyme, which aids in cutting..

Pasteurization process

4. Products that can be pasteurized:a) Cheese b) Water c) Milkd) Beere) Eggsf) Almondsg) Juice

b) Fermentation1. Fermentation in food processing typically refers to the conversion of sugar to

alcohol using yeast, bacteria or a combination thereof, under anaerobic conditions.

2. More general definition of fermentation is the chemical conversion of carbohydrates into alcohols or acids. When fermentation stops prior to complete conversion of sugar to alcohol, a stuck fermentation is said to have occurred.

3. The science of fermentation is known as zymology. Fermentation usually implies that the action of the microorganisms is desirable and the process is used to produce alcoholic beverages such as wine, beer, and cider.

4. Fermentation is also employed in preservation to create lactic acid in sour foods such as pickled cucumbers, kimchi and yogurts.

Beer fermenting at brewery

Natto, a Japanese fermented soybean food

5. The main purpose of food fermentation: Enrichment of the diet through development of a diversity of flavors,

aromas, and textures in food substrates. Preservation of substantial amounts of food through lactic acid, alcohol,

acetic acid and alkaline fermentations. Biological enrichment of food substrates with protein, essential amino acids,

essential fatty acids, and vitamins. Detoxification during food-fermentation processing. A decrease in cooking times and fuel requirements.

c) Cooking

1. Cooking is the process of preparing food by applying heat, selecting, measuring, and combining of ingredients in an ordered procedure for producing safe and edible food.

2. The process encompasses a vast range method of methods, tools and combination of ingredients to alter the flavor, appearance, texture or digestibility of food.

3. Factors affecting the final outcome include the variability of ingredients, ambient conditions, tools and the skill of the individual doing the actual cooking.

4. Applying heat to food usually, though not always, chemically transform it, thus changing its flavor, texture, consistency, appearance and nutritional properties.

5. Methods of cooking that involve the boiling of liquid in a reacceptance have been practiced at least since the 10th millennium BC, with the introduction of pottery.

d) Preservationa) salt1. Salting is the preservation of food with dry salt. It is related to pickling (preparing

food with brine, i.e. salty water) 2. It is one of the oldest methods of preserving food, and two historically significant

such foods are dried and salted cod (usually referred to as salt fish) and salt-cured meat.

3. Salting is used because most bacteria, fungi and other potentially pathogenic organisms cannot survive in a highly salty environment, due to the hypertonic nature of salt.

4. Any living cell in such an environment will become dehydrated trough osmosis and die or become temporarily inactivated

Preservation using salt

b) Sugaring1. Sugaring is a food preservation method similar to pickling. Sugaring is the

process of desiccating a food by first dehydrating it, then packing it with pure sugar.

2. This sugar can be crystalline in the form of table or raw sugar, or it can be a high sugar density liquid such as honey, syrup or molasses

3. The purpose of sugaring is to create an environment hostile to microbial life and prevent food spoilage. Sugaring is commonly used to preserve fruits as well as vegetables such as ginger.

4. From time to time sugaring also has been used for non-food preservations.

5. A risk in sugaring is that sugar itself attracts moisture. Once a sufficient moisture level is reached, native yeast in the environment will come out of dormancy and begin to ferment the sugars into alcohol and carbon dioxide.

6. This leads to the process of fermentation. Although fermentation can be used as a food preservation method, it must be intentionally controlled, or the results will tend to be unpleasant

c) Vinegar1. Now a relatively common practice to bottle vegetables, herbs and spices in oil,

vinegar or mixture of both.2. This is done both commercially and domestically and the products should be

refrigerated below 4°C.3. Products which are treated in this way include chopped garlic, garlic cloves, sun-

dried tomatoes, chili, ginger and capsicum. 4. Acetic acid in the vinegar prevents microbial growth. The more concentrated

vinegar absorbs water from food and microorganisms by osmosis5. While these products are safe if refrigerated, they represent a potential food

poisoning hazard unless certain basic precautions are taken in their preservation.

e) Canning1. Canning is a method of preserving food in which the food is processed and sealed

in an airtight container. The process was first developed as a French military discovery by Nicolas Appert. The packaging prevents microorganisms from entering and proliferating inside.

2. From a public safety point of view, foods with low acidity (a pH more than 4.6) need sterilization under high temperature (116-130°C). To achieve temperatures above the boiling point requires the use of a pressure canner. Foods that must be pressure canned include most vegetables, meats, seafood, poultry, and dairy products. The only foods that may be safely canned in an ordinary boiling water bath are highly acidic ones with a pH below 4.6, such as fruits, pickled vegetables, or other foods to which acidic additives have been added.

(a)

(b)Figure (a) and (b) shows the canning of food

f) Drying

1. Drying is a method of food preservation that works by removing water from the food, which prevents the growth of microorganisms and decay. Drying food using the sun and wind to prevent spoilage has been known since ancient times. Water is usually removed by evaporation (air drying, sun drying, smoking or wind drying) but, in the case of freeze-drying, food is first dried and then water is removed by sublimation.

2. Bacteria and micro-organisms within the food and from the air need the water in the food to grow. Drying effectively prevents them from surviving in the food. It also creates a hard outer-layer, helping to stop micro-organisms from entering the food.

3. Many different foods are prepared by dehydration. Good examples are meat such as prosciutto (a.k.a. Parma ham), bresaola, and beef jerky. Dried and salted reindeer meat is a traditional Sami food. First the meat is soaked / pickled in saltwater for a couple of days to guarantee the conservation of the meat. Then the meat is dried in the sun in spring when the air temperature is below zero. The dried meat can be further processed to make soup.

4. Fruits change character completely when dried: the plum becomes a prune, the grape a raisin; figs and dates are also transformed.

5. Drying is rarely used for vegetables for use in the household however dehydrated vegetables are often found in commercially packaged meals as well as meals made for backpackers, hunters, military, etc. The exceptions to this rule are bulbs, such as garlic and onion, which are often dried. Also chilies are frequently dried. Edible and psilocybin mushrooms, as well as other fungi, are also sometimes dried for preservation purposes, to affect the potency of chemical components, or so they can be used as seasonings.

6. For centuries, much of the European diet depended on dried cod, known as salt cod or bacalhau (with salt) or stockfish (without). It formed the main protein source for the slaves on the West Indian plantations, and was a major economic force within the triangular trade. Dried shark meat, known as Hákarl, is a delicacy in Iceland.

A collection of dried mushrooms

g) Refrigeration

1. Refrigeration slows bacterial growth. Bacteria exist everywhere in nature. They are in the soil, air, water and the foods we eat. When they have nutrients (food), moisture, and favorable temperature, they grow rapidly, increasing in numbers to the point where some types of bacteria can cause illness.

2. Bacteria grow most rapidly in the range of temperatures between 40° and 140°F, the “Danger Zone”, some doubling in number in as little as 20 minutes

3. A refrigerator set at 40°F or below will protect most foods.4. For safety it is important to verify the temperature of the refrigerator. Refrigerators

should be set to maintain a temperature of 40°F or below.

STORAGE TIMES FOR REFRIGERATED FOODS:

FOOD REFRIGERATION TIMEEggs

Fresh in shell 3-5 weeksRaw yolks, whites 2-4 daysHard-cooked 1 weekLiquid pasteurized eggs, egg substitutes Unopened, 10 days

Opened, 3 daysCooked egg dishes 3-4 days

Deli and vacuum-Packed products

Stored prepared egg, chicken, tuna, ham, and macaroni salads

3-5 days

Lamb chops, and chicken breasts 1 dayStore-cooked dinners and entrees 3-4 days

Raw Hamburger, Ground and Stew Meat

Ground beef, turkey, veal, lamb 1-2 daysStew meats 1-2 days

Refrigeration of food

1. Food spoilage means the original nutritional value, texture, flavour of the food are damaged, the food become harmful to people and unsuitable to eat.

2. There are 3 factors that cause food spoilage:a) Microbial spoilageb) Autolysisc) Other factors

3. Bacteria are round, rod or spiral shaped microorganisms. Bacteria may grow under a wide variety of conditions. There are many types of bacteria that cause spoilage. They can be divided into: spore-forming and no spore-forming. Bacteria generally prefer low acid foods like vegetables and meat. In order to destroy bacteria spores in a relatively short period of time, low acid foods must be processed for the appropriate length of time at 116°C (240°F) in a pressure canner. (Temperatures higher than 100°C [212°F] can be obtained only by pressure canning.)

4. Eating spoiled food caused by bacteria can cause food poisoning.5. Enzymes are proteins found in all plants and animals. If uncooked foods are not used

while fresh, enzymes cause undesirable changes in colour, texture and flavour. Enzymes are destroyed easily by heat processing.Atmospheric oxygen can react with some food components which may cause rancidity or color changes.

6. Other factors

Infestations (invasions) by insects and rodents, which account for huge losses in food stocks.

Low temperature injury - the internal structures of the food are damaged by very low temperature.

The picture of spoiled food

SEKOLAH SULTAN ALAM SHAH

PUTRAJAYA

PORTFOLIO:

BIOLOGY

(Form 4)

NAME: MUHAMMAD ADLI BIN BADIAU ZAMAN

CLASS: 4 USAHA

1. Food processing dates back to the prehistoric ages when crude processing incorporated slaughtering, fermenting, sun drying, preserving with salt, and various types of cooking (such as roasting, smoking, steaming, and oven baking). Salt-preservation was especially common for foods that constituted warrior and sailors' diets, up until the introduction of canning methods. Evidence for the existence of these methods exists in the writings of the ancient Greek , Chaldean, Egyptian and Roman civilizations as well as archaeological evidence from Europe, North and South America and Asia. These tried and tested processing techniques remained essentially the same until the advent of the industrial revolution. Examples of ready-meals also exist from pre industrial revolution times such as the Cornish pasty and the Haggis

2. Modern food processing technology in the 19th and 20th century was largely developed to serve military needs. In 1809 Nicolas Appett invented a vacuum bottling technique that would supply food for French troops, and this contributed to the development of tinning and then canning by Peter Durand in 1810. Although initially expensive and somewhat hazardous due to the lead used in cans, canned goods would later become a staple around the world. Pasteurization, discovered by Louis Pasteur in 1862, was a significant advance in ensuring the micro-biological safety of food.

3. In the 20th century, World War II, the space race and the rising consumer society in developed countries (including the United States) contributed to the growth of food processing with such advances as spray drying, juice concentrates, freeze drying and the introduction of artificial sweeteners, colouring agents, and preservatives such as sodium benzoate. In the late 20th century products such as dried instant soups, reconstituted fruits and juices, and self cooking meals such as MRE food ration were developed.

4. In western Europe and North America, the second half of the 20th century witnessed a rise in the pursuit of convenience, food processors especially marketed their products to middle-class working wives and mothers. Frozen foods (often credited to Clarence Birdseye) found their success in sales of juice concentrates and "TV dinners ".Processors utilised the perceived value of time to appeal to the postwar population, and this same appeal contributes to the success of convenience foods today.

There have seven methods of food processing:

a) Pasteurization

b) Fermentation

c) Cooking

d) Preservation

e) Canning

f) Drying

g) Refrigeration