food processing and preservation

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PROCESSED AND PRESERVED FOODS, SEASONINGS AND ADDITIVES

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Page 1: Food Processing  and Preservation

PROCESSED AND PRESERVED FOODS, SEASONINGS AND ADDITIVES

Page 2: Food Processing  and Preservation
Page 3: Food Processing  and Preservation

FOOD PROCESSINGWHAT?

Food processing is the transformation

of raw ingredients into food, or of food

into other forms. Food processing is typically a

mechanical process that utilizes large mixing, grinding, chopping and emulsifying equipment in the production process

Page 4: Food Processing  and Preservation

HOW? Food processing typically takes

clean, harvested crops or butchered animal products

WHY? To produce attractive,

marketable and often long shelf-life food products

Page 5: Food Processing  and Preservation

ADVANTAGES OF FOOD PROCESSING1. Toxin removal2. Preservation3. Easing marketing and

distribution tasks4. Increasing food consistency,

improves taste

Page 6: Food Processing  and Preservation

5. It increases yearly availability of many foods

6. Enables transportation of delicate perishable foods across long distances

7. Makes many kinds of foods safe to eat by de-activating spoilage and pathogenic micro-organisms.

8. Large profit potential for manufacturers

Page 7: Food Processing  and Preservation

RISKS AND DISADVANTAGES

1. Loss of nutritive value2. Possible Contamination• physical ( hair,

metals,fingernails,stones)• chemical (excess salt, sugar,

acids,cleaning agents• Microbial (Salmonella, E. coli,

parasites,fungi)

Page 8: Food Processing  and Preservation

Nearly every food preparation process reduces the amount of nutrients in food. In particular, processes that expose foods to high levels of heat, light, and/or oxygen cause the greatest nutrient loss. Nutrients can also be "washed out" of foods by fluids that are introduced during a cooking process. Similar losses also occur when you broil, roast, or fry in oil, and then drain off the drippings

Page 9: Food Processing  and Preservation

FACTORS TO BE CONSIDERED Hygiene, e.g. measured by number of micro-

organisms per ml of finished product Energy efficiency measured e.g. by “ton of

steam per ton of sugar produced” Minimization of waste, measured e.g. by

“percentage of peeling loss during the peeling of potatoes'

Labour used, measured e.g. by ”number of working hours per ton of finished product”

Minimization of cleaning stops measured e.g. by “number of hours between cleaning stops”

Page 10: Food Processing  and Preservation

FOOD PRESERVATION

Food preservation is the process of treating and handling food to stop or slow down food spoilage, loss of quality, edibility or nutritional value and thus allow for longer food storage.

Page 11: Food Processing  and Preservation

METHODS OF PRESERVING FOOD1. Drying - one of the most ancient food

preservation techniques, which reduces water activity sufficiently to prevent bacterial growth.

2. Refrigeration - preserves food by slowing down

the growth and reproduction of micro-organisms and the action of enzymes which cause food to rot

Page 12: Food Processing  and Preservation

3. Freezing- (0 to -17 C)4. Vacuum packing A vacuum environment, usually in an

air-tight bag or bottle strips bacteria of oxygen needed for survival, slowing spoiling. Vacuum-packing is commonly used for storing nuts to reduce loss of flavor from oxidation.

5. Addition of salt/ curing Salt draws water through Osmosis,

Prague powder(NaNO2 + Salt) gives it a distinctive pink colour)

Page 13: Food Processing  and Preservation

6. Sugar7. Smoking Chemical components from the smoke of

burning wood: a. Nitrogen oxides form nistrosamines with

meat and fish b. Polycyclic

aromatichydrocarbons,phenols,furans,tar8. ArtificiaL Food Additives Common antimicrobial preservatives include

calcium propionate, sodium nitrate, sodium nitrite, sulfites (sulfur dioxide, sodium bisulfite, potassium hydrogen sulfite, etc.) and disodium EDTA. Antioxidants include BHA and BHT. Other preservatives include formaldehyde (usually in solution), glutaraldehyde (kills insects), ethanol and methylchloroisothiazolinone.

Page 14: Food Processing  and Preservation

9. Jellying10. Irradiation ( exposure to Xrays, gamma

rays)11. High Pressure processing12. Burying in the Ground(lack of light,

oxygen,lowpH,cool temp, dessicants in soil)13. Biopreservation (addition of LAB)14. Pickling a. Chemical (brine,vinegar, oil) b. Fermentation (lactic acid produced by the

food itself)15. Addition of Lye -NaOH prevents bacterial growth,

saponifies fats16. Canning and Bottling

Page 15: Food Processing  and Preservation

FOOD ADDITIVES

These are substancesadded to food to preserve flavor or enhance its taste and appearance.

a. Intentional(added on purpose)

b. Incidental (unintentional)

Page 16: Food Processing  and Preservation

TYPES OF

FOOD ADDITIVES

Page 17: Food Processing  and Preservation

Acids -added to make flavors "sharper", and also act as preservatives and antioxidants. Common food acids include vinegar, citric acid, tartaric acid, malic acid, fumaric acid, and lactic acid.

Acidity regulators  are used to change or otherwise control the acidity and alkalinity of foods.

Anticaking agents  keep powders such as milk powder from caking or sticking. Antifoaming agents 

Antifoaming agents reduce or prevent foaming in foods.

Page 18: Food Processing  and Preservation

Antioxidants  such as vitamin C act as preservatives by inhibiting the effects of oxygen on food, and can be beneficial to health.

Bulking agents  such as starch are additives that increase the bulk of a food without affecting its taste.

Food coloring are added to food to replace colors lost during preparation, or to make food look more attractive.

Color retention agents are used to preserve a food's existing color.

Page 19: Food Processing  and Preservation

Emulsifiers  allow water and oils to remain mixed together in an emulsion, as in mayonnaise, ice cream, and homogenized milk.

Flavors  give food a particular taste or smell, and may be derived from natural ingredients or created artificially.

Flavor enhancers  enhance a food's existing flavors. They may be extracted from natural sources (through distillation, solvent extraction, maceration, among other methods) or created artificially.

Flour treatment agents  are added to flour to improve its color or its use in baking

Page 20: Food Processing  and Preservation

Glazing agents provide a shiny appearance or protective coating to foods.

Humectants  prevent foods from drying out.

Preservatives  prevent or inhibit spoilage of food due to fungi, bacteria and other microorganisms.

Stabilizers  thickeners and gelling agents, like agar or pectin(used in jam for example) give foods a firmer texture. While they are not true emulsifiers, they help to stabilize emulsions.

Page 21: Food Processing  and Preservation

Sweeteners  are added to foods for flavoring. Sweeteners other than sugar are added to keep the food energy (calories) low, or because they have beneficial effects for diabetes mellitus and tooth decay and diarrhea.

Thickeners  are substances which, when added to the mixture, increase its viscosity without substantially modifying its other properties.

Page 26: Food Processing  and Preservation

Referrences

Riddervold, Astri. Food Conservation. ISBN 978-0-907325-40-6.

Abakarov, Nunes. "Thermal food processing optimization: algorithms and software". Food Engineering (http://tomakechoice.com/paper/OPTPROx.pdf.

Abakarov, Sushkov, Mascheroni. "Multi-criteria optimization and decision-making approach for improving of food engineering processes". International Journal of Food Studies (http://tomakechoice.com/paper/MCDM&OD_IJFS.pdf).

Page 27: Food Processing  and Preservation

Fábricas de alimentos, 9th edition (in Spanish) Nutritional evaluation of food processing, Food preservation 2nd edition, by Normal W.

Desrosier Department of Food Technology, University

College of Technology, Osmania University, Hyderabad, Andhra Pradesh, India

University of California directory of academic and industry literature

FOOD ADDICTION | The Perils of Processed Foods in America’s Diet