Foods of Αnimal Origin Exam 2

What are the 3 principles of food preservation

Shelf life, food safety, and food quality

What are the steps food goes through before reaching consumer

Production, processing, storage, distribution, retail, and consumption

What is the term that describes the process or change which renders a product undesirable or unacceptable for consumption

Food spoilage

How much total food is wasted in the food supply

30-40%

What are the 3 categories for foods in terms of how long they can be kept without any treatment

Non-perishable, semi-perishable, and perishable

What is an example of a non-perishable food

Grain, flour, or sugar

What is an example of a semi-perishable food

Potatoes, apples, or onions

What is an example of perishable foods

Milk, eggs, or meat

In terms of amount of water and protein where do nonperisable food items lie

Very little water and/or protein

In terms of water and protein amounts how much do semi-perishable foods have

Contain less water and protein

Majority of semi-perishable foods come from

A. Animal sources

B. Plant sources

B

What is the water activity and protein concentration for perishable foods

High water activity and high protein concentration

What are the 3 main aspects of perishable animal derived products

High level of protein, moisture, and carbohydrates

What is the rate of spoilage dependent on in animal derived products that are perishable

Temperature, moisture, or dryness of environment

What are the 4 main reasons for processing and preserving animal products

Extend shelf life, increase food safety, enhance quality, and add value

Because foods are derived from __________ they are subject to the natural process of decomposition

Living matter

In terms of food spoilage what is often not detectable

Contamination

What are the 3 main causes of food spoilage

Biological, chemical, and physical changes

What are the biological components of food spoilage?

Bacteria, yeast, and molds

What foods do bacteria infect for food spoilage

Meat, eggs, and milk

What foods do yeast infect for food spoilage

High-sugar foods

What foods do molds infect for food spoilage

High-sugar foods such as cheese and bread

How do chemicals cause food spoilage

Enzymatic action accelerates spoilage

What in the function of proteases

Breaks down protein and causes food spoilage in fish

What is the function of lipases

Breaks down lipids and causes rancidty in food

What is the function of carbohydrases

Break down carbohydrates and spoil fruits and vegetables

What are some exmaples of physical changes that cause food spoilage

Evaporation, drip loss, syneresis, and separation

What is the term used to describe the conversion of raw animal and plant tissue into forms that are convenient and practical to consume

Processing

What is the term used to described the use of specific thermal and nonthermal techniques to minimize the number of spoilage microorganisms in food

Food preservation

Principles of food preservation are based on controlling environmental conditions of the food. What are these conditions?

Water activity, temperature, and pH

What are the 4 principles of food preservation?

Inhibit the growth and activity of microorganisms, protect from invasion and spoilage by insects and rodents, protect against loss due to mechanical/processing causes, and delay/prevent food self-decomposition

What are the 7 aspects of food preservation methods

Moisture, Temperature, pH, fermentation, irradiation, chemical, and packaging

What is the goal of food preservation methods

To reduce or remove conditions that allow spoilage microorganisms to grow

What are the 2 factors that affect preservation methods

Food items and quantity to be preserved

What are the 2 classification categories for food preservation methods

Bactericidal and Bacteriostatic

What happens to microorganisms in bactericidal methods

Most are killed

What are some examples of bactericidal methods

Cooking, canning, pasteurization, sterilization, and irradiation

What do bacteriostatic methods do to microorganisms

Prevent them from growing/multiplying

How is the prevention of microorganisms growth/multiplication in bacteriostatic methods

Removal of water, addition of acids, oils, or spices, and keeping the foodstuff at a low temperature

What are examples of bacteriostatic methods

Drying, freezing, pickling, salting, and smoking

What are ways of moisture-based preservation

Drying, curing, and smoking

In moisture-based preservation moisture content is reduced to inhibit microbial growth usually by adding ______________

Salt, sugar, or nitrates

What are different drying methods for moisture removal

Sun drying, drum drying, spray drying, and freeze drying

T or F: foods of equal/similar moisture content can have different water activity

True

At what water activity can most molds grow

70%

At what water activity can most yeasts grow

80%

At what water activity can most gram positive bacteria grow

85%

At what water activity can gram negative bacteria grow?

90%

What is the term used to describe the use of salt to bind free water in food and thus making it unavailable for microorganisms

Curing

How is smoking cured meats able to remove moisture

Has a drying effect which also adds flavor, texture, and color

What are tempearture-based preservation methods

Chilling, freezing, and heating

What are the 4 forms of heat treatment in temperature based preservation?

Sterilization, pasteurization, blanching, and canning

What are the objectives of pasteruization

Destroy organisms that could affect public health, extend shelf life, flavor change, and nutrient loss small

T or F: once pasteurized products contain no more living organisms

False: they do still contain living organisms

What is the objective of low-temperature treatment for food preservation

To slow down the biological, chemical, and physical reactions that shorten the shelf life of food products

What is the term used to describe managing temperature of perishable food from the point of origin to final consumer

Cold chain

Fish, meats, poultry, and dairy products should be held at temperatures _________________

Just above freezing but as near to 0ºC

What is the ideal home refrigerator temperature

1.1-3.3ºC

How does freezing preserve food in terms of water activity

Freezing solidifies water which lowers water activity which makes water unavailable for microorganisms

How does freezing preserve food in terms of chemical reactions

Slows chemical reactions

All detectable water in foods is converted to ice at what temperature

-60ºC

Freezing foods at ________ or below is the least damaging to the foods original flavor, nutrient content, and texture

-18ºC

T or F: the faster the food freezes, the more the food is damaged in the process

False: the less the food is damaged in the process

What determines whether and for how long a food can be stored in the freezer

Composition

What is an example of a food that does not freeze well

Some dairy products

Why do dairy products not freeze well

The higher a food’s fat content, the shorter its life span in the freezer

Why does fat in diary products become rancid even when frozen

Damage to the milk fat globule membranes exposes the milk lipids to enzymes and oxidation

What are the problems with freezing food

Dries out surface, damages texture of foods, fluid loss, and recrystallization

What are some nonthermal processing methods for food

Irradiation, radio frequency, pulsed light, high-pressure processing, ozonation, and pulsed electric field

What are the processes of irradiation in food preservation

Treats foods with low doses of gamma rays, x-rays, and electron beams

How is irradiation able to kill of microorganisms

It causes free radials to be created with water which disrupts DNA and other components of the microorganisms

How does irradiation effect meat

It can be kept longer in the refrigerator

How is radio frequency used in nonthermal processing

Electromagnetic waves are converted into heat to increase food temperatures

What type of foods are best suited for radio frequency as food processing

Dried ingredients such as flour, seeds, cereal grains, and protein powder

How does pulsed light preserve food

Disrupts the cell membrane of bacterial cells using exposure of intense brief light flashes

How does high-pressure processing preserve foods

Deactivates enzymes that cause spoilage by exposing foods to extremely high pressure

What types of foods is high-pressure processing used on

Ready-to-eat meats and shellfish

What bacterial growth is ozonation effective for controlling

E. Coli and salmonella

Ozone effectively kills ____________

Viruses, molds, and bacteria

How does pulsed electric fields preserve food

Disrupts biological cells in the food matrix with short high voltage pulses

Compared to all other heat treatments what one is most economical

Pulsed electric fields

What type of foods is pulsed electric fields used on for food preservation

Milk and liquid whole eggs

What is the term for antimicrobial chemical additives

Preservatives

What are some examples of preservatives

Food acidulant additves, sucrose, sodium chloride, sulfur dioxide, and antioxidant compounds

What are the two ways in which preservatives work

Microbial position or reduce pH to a level that prevent microbial growth

What are the common chemicals included in chemical preservatives

Nitrates and nitrites for meat preservation and sulphites to preventing browning and fungal spoilage

What is able to offer protection from biological, chemical, and physical factors that would speed up food deterioration

Packaging

What type of packaging is able to change the composition of the air around the food to prolong shelf-life

Modified-atmosphere packaging

What type of foods is modified-atompshere packing used for

Meats, poultry, seafood, and cured cheeses

What type of packaging removes air from the space of the packaged food

Vacuum packaging

How is vacuum packaging able to maintain a fresh red color to the meat

Prevents oxidative changes in myoglobin

What is the term used to describe the stress placed on a microorganism that it must overcome in order to survive, grow, and reproduce in food

Hurdle

What are the factors of innovative hurdle technologies for food preservation

Water activity, pH, temperature, pressure, and chemical antimicrobials

What is the purpose of hurdle technology

To create a combination of suboptimal growth conditions in which each factor alone would be insufficient to prevent the growth of pathogenic organisms

What is the basic definition of meat

Flesh of animals used for food

What is the simple definition of poultry

Domesticated birds raised for their meat

What is the technical definition of meat

The part of the muscle of cattle, sheep, swine, or goats which is skeletal or found in the tongue, diaphragm, heart, or esophagus, with or without overlying fat, and the portions of bones, sinew, nerve, and blood vessels that accompany muscle tissue and are not separated ruing dressing

What animals are included in the technical definition of meat

Cattle, sheep, swine, or goats

Meat does not include the muscle found in what parts of the body

Lips, snout, or ears

Meat = ?

Muscle