Food Engineering

Food Engineering (Food Processing & Manufacturing Science)

Dr. Mukund V. Karwe ([email protected])

C

(http://foodsci.rutgers.edu)

Food Engineering • Food Manufacturing Industry the second largest manufacturing sector in the US with sales over $650 billion covering a very wide range of prepared foods

Example: Frozen foods Total frozen food sales $29.2 billion

What is Food Engineering ? FLOUR

Bagel

Bread

Croissant

Filled Croissant

MILK

Milk Powder

Yogurt

Ice Cream

Cheese

What is Food Engineering ? Application of engineering and science principles to enable the development of food processing operations for the manufacture of foods in large quantities and with narrow tolerances to deliver to the consumer high quality, safe and healthy foods.

Raw materials Process design and optimization Equipment design Process control Packaging

Processed foods

The History of Convenience Foods • Convenience foods (packaged soups, frozen meals, prepared sauces and flavorings) date back centuries. • Humans have always needed to obtain food and store a portion for later use. Prehistoric humans may have dried fruits in the sun and stored meat in cold areas, such as caves. • The modern food processing and preservation industry was born in 1800s. • In 1809, when French chef and inventor Nicolas Appert searching for a better way to provide food for Napoleon’s army, devised a method for sterilizing food in tightly sealed glass bottles.

The History of Convenience Foods • In 1882 Swiss Public Welfare Society offered a series of recommendations, including an increase in the consumption of vegetables. • The Society commissioned Julius Maggi, a miller with a reputation as an inventive and capable businessman, to create a vegetable food product that would be quick to prepare and easy to digest. • The results-two instant pea soups and an instant bean souphelped launch one of the best known brands in the history of the food industry. • By the turn of the century, Maggi & Company was producing not only powdered soups, but bouillon cubes, sauces and flavorings.

Milestones in Food Technology in the last 200 years 1809

Nicholas Appert used glass containers to sterilize food (for Napoleon)

1818

Tin Can used for food storage (in U.S.) Peter Durand (U.K.)

1840

Instant gelatin (Peter Cooper, NY)

1870

Margarine as a substitute for butter

1871

Chewing gum introduced (Philadelphia)

1886

Coca Cola introduced (Atlanta pharmacist John Pemberton)

1890

Peanut butter introduced

1894

Cold cereal cornflakes introduced (W.K. Kellogg)

1904

Thermos flask developed (Dewar) Ice cream cone

1941

M&M candy introduced (Forrest Mars)

1946

Teflon as a non-stick cooking surface (DuPont)

1947

Microwave oven to heat food

1953

Saran Wrap by Dow Chemicals (MW safe plastic): polyvinylidene chloride

1955

First McDonald’s in California

1961

Space foods (Lunar missions)

1973

Plastic (which?) bottles for soda (soft drink)

1976

Pop-top soda can

1980s

High Pressure food processing

1990s

Food Processing using ‘field’

~1995

Outer space (Mars mission) food technology initiated

2002

Food Nanotechnology, Food Informatics

How bakery products and frozen dough are made?

Industrial-scale bread production 1) Ingredient mixing and dough development, 2) Automatic dough slicing and depositing into bread pans/trays,

Thank You

3) Proofing/second rise, 4) Baking the loaves in hot-air convection oven, 5) Cooling the bread, 6) Separating the loaves from the bread pans, 7) Slicing and packaging, 8) Delivery to retail outlets.

http://encarta.msn.com//Industrial_Scale_Bread_Making.html

Bread production

Dough mixer

Dough divider

Proofing of dough: allowing dough to rise to get all the bubbles that give it a great texture

Conveyor belts

http://www.foodprocessing-technology.com/contractors/materials/habasit/

Moulding and stamping of bakery products on the continuous processing line

www.foodprocessing-technology.com/

Baking of dough requires large ovens Tunnel oven

Industrial tunnel oven

www.foodprocessing-technology.com/

Ice cream • Ice cream, popular frozen food made of milk, cream, sugar, and flavoring. • It was first made in Italy in the 17th century and appeared in the US in the early 18th century. The US ice-cream manufacturing industry began in 1851. • Early production methods consisted of placing the ingredients in a metal container, surrounded by a freezing mixture of ice and coarse salt, and mixing them until smooth. • The story of its popularity is connected with the invention of technology to make it on an industrial scale, and to keep it cold once made. • At the end of the 19th century, both making and freezing it became easier, and together with the invention of the ice cream cone, made the product boom.

Industrial-scale ice cream production In modern plants the ingredients are poured into a tank, where they are mixed and pasteurized. The mixture is then homogenized to break up particles of butterfat, cooled, piped to a freezing tank, and beaten until smooth; at this stage nuts or fruits are added. The ice cream emerges from the freezing tank partially frozen and is packed into containers that are stored in a refrigerated room until hard. http://www.bosgear.com/segments/food.html

Industrial freezer

Ice cream structure under electron microscope

www.foodprocessing-technology.com/

Manufacture of dairy products - Cheese - Yogurt - Milk powder

Collection of milk from farms with large milk tankers

www.foodprocessing-technology.com/

Skim milk and yogurt manufacture

Milk evaporators

Yogurt fermentation vessel

Cream separators

Yogurt filling

How milk powder is made?

Spray dryer Falling film evaporator www.foodprocessing-technology.com/

Milk powder

How cheese is made? [left] separating and cutting curds [right] cheese maturation and warehousing

Curds and whey pumped into the vat

Maturation of cheeses on environmentally controlled racks

How cheese is made?

Cheese moulding machinery Cheese blocks Cheese wedges

Truckle of cheese being sliced http://www.repete.com/solutions.html

How are these made?

Food Extruder

Pasta & Cereal manufacturing

8,000kg/h spaghetti production line

Close-up of the pasta press

8,000kg/h pasta press

www.foodprocessing-technology.com/

Spaghetti drying Pasta packaging

www.foodprocessing-technology.com/

Twin Screw Extruder (making corn pops)

(Dr. Karwe’s lab)

Food extrusion die

Corn flakes production line

aerator mixing head used in confectionary industry

Mixer for continuous aeration of fat based creams and chocolates

marshmallow chicks

Marshmallows extruded in continuous ropes on starch-dusted conveyors. www.foodprocessing-technology.com/

Robots in food industry

packaging-line robot

www.foodprocessing-technology.com/

parallel-arm robot for highspeed picking and packing applications.

Packaging • Regardless of the processing or preservation method used, proper packaging of food is essential to make sure the food remains wholesome during its journey from processor to consumer. • Packaging helps the delivery to the consumer of carefully metered or weighed quantities of foods in a pleasing way and also protects the food from spoilage and increases its shelf life. • Packaging contains food and makes it easier to handle during transport and storage. • Selection of packaging material is critical and depends on the characteristics of the product to be packaged. For example, milk is often stored in opaque containers to prevent vitamins from being destroyed by light. • Individualized delivery of food requires very fast packaging lines filling millions of packages a week (sometimes a day).

Thermal Processing Objectives: • Render foods free of pathogenic & spoilage organisms • Impart changes in texture, color, flavor • Improve digestibility • Improve shelf life

Blanching carried out before sterilization, dehydration, and freezing to deactivate enzymes and reduce surface load of microbes in vegetables and some fruits Pasteurization is carried out for low acid foods (pH > 4.5) to kill pathogenic microorganisms. (Milk: 15 s at 71.5 °C) and for acidic foods (pH < 4.5) to extend shelf life by killing spoilage microorganisms (molds, yeasts) Heat sterlization is carried out to kill the enzymes and microbes (high temp > 100 °C). Canned food and aspectically packaged food

Microwave Heating • Interaction of EM field with food (containing water and fat) • Conversion of electrical energy to heat • More penetration at lower frequency • Non-contact • Rapid heating • Surface does not overheat (but no crust formation)

What are microwaves? • Electromagnetic waves of radiant energy • Just like light or radio waves, and different only in wavelength • Longer than IR, shorter than radio waves

Properties of microwaves • • • •

Travel in straight lines Reflected by metals, Pass through air Generally pass through glass, paper, plastic Absorbed by water and other food components Does oil heat in a microwave oven?

Microwave Oven  Transfer of microwave energy from a magnetron to the food product  Electromagnetic spectrum between 300 MHz and 3000 MHz frequency

 2450 MHz for domestic microwave ovens 2450 MHz or 915 MHz for industrial systems Source: http://www.zebu.uoregon.edu/~js/ast123/ lectures/lec03.html

Inherent disadvantages of thermal processing

Loss of original flavor, taste, appearance, color nutritional quality

“Newer” Processing Methods

Non-Thermal Processing

Objectives: • Render foods free of pathogenic & spoilage organisms • Retain color, flavor • Improve shelf life • Improve texture

Examples of Non-thermal Processes • • • • • • • •

High Hydrostatic Pressure (HHP) Pulsed Electric Field (PEF) Ultrasound Pulsed Light (PL) Irradiation Electron Beam Oscillating Magnetic Field (OMF) Gas, plasma

High Pressure Processing

High pressure processing (HPP), or high hydrostatic pressure (HHP), or ultra high pressure (UHP) processing, subjects liquid or solid foods, with or without packaging, to pressures between 40 and 1000 MPa ( 1-20 min).

Three African elephants (~5 tons each) standing on a 18 mm (dia.) disk

(18 mm in diameter) 600 MPa or 87,000 psi

Traditionally shucked muscle & tissue damage

HPP shucked

Adductor muscle intact

Pericardial cavity intact

Oysters

HHP Processed Current and Potential Products in the Market Apple cider, fruit smoothies, Ham, chicken, turkey, sausages Oysters, Clams, other shell fish Hummus, Guacamole, Salsa, wet salads

High Intensity Pulsed Light Processing • Intense, short duration, broad-spectrum light is exposed to a food or package • Very effective on product surfaces • Marginally effective at penetrating to depths in foods • Reduces the need for chemical disinfectants and preservatives

Lamp

Shelf

 FDA approved Pulsed Light Technology for food (21CFR, Part 179, 1996) Source: Dr. Carmen Moraru

Radiation vs. Irradiation • Radiation: Mode of heat transfer in vacuum

Non-Ionizing Radiation: RF, microwaves, IR

Ionizing Radiation: X-rays, gamma rays, and energy from radioactive isotopes. 

Irradiation:: Ionizing radiation Irradiation

Current Food Products Processed by Ionizing Radiation Potatoes, Spices, Dry vegetable seasoning, Ground beef, pork, poultry, Some fruits and vegetables More than 150 food irradiation facilities in 40 countries

“Food irradiation is one of the most extensively and thoroughly studied methods of food preservation” Thakur and Singh (1994)

Labeling Requirements • Irradiated foods are required to have either “treated with irradiation” or “treated by irradiation” displayed prominently on the label. • “Radura” must be displayed. • Ingredients (e.g. spices) are not required to have any labeling. • Restaurant foods do not require labeling

Consumer Acceptance

“The greatest disadvantage of food irradiation is its name…evokes unpleasant associations of radioactivity, nuclear threats, high technology, genetic mutation, and cancer”

GAS PLASMA PROCESSING

PLASMA  Plasma is the fourth state of matter A higher energy state than gas, liquid or solid  Most of the universe is made up of plasma Sun Stars Lightning Neon lights

PLASMA  Plasma can be generated by passing a current between 2 electrodes through a gas. Its application in food industry includes: – Food packaging – Microbial safety

Food engineering/processing/ manufacturing delivers a wide range of high quality, healthy foods in a convenient, safe and shelf stable way to the consumer.

THANK YOU