Food Science - Exam 2 Review Guide

Heathy eating involves the principles of:

- Adequacy
- Balance
- Variety
- Moderation

Adequacy and balance:

- Diet provides all the essential nutrients, fiber, and energy
- Diet provides the correct proportion of nutrients

Moderation

- Diet provides reasonable but not excessive amounts or foods and nutrients
- Awareness of portion size and number of servings

Portion

The amount of food eaten in one sitting

Malnutrition

- Consuming either too much or too little of one or more nutrients or energy will result in malnutrition
- Under Nutrition & Over Nutrition: both deemed malnutrition

2 conditions of Malnutrition that affects children:

- KWASHIORKOR
- MARASMUS

Eating disorders

- Anorexia Nervosa
- Bulimia
- Orthorexia: Condition that includes symptoms of obsessive behavior in pursuit of a healthy diet

Typical US Diet

Diet pattern high in red meat, saturated fats, low in fruits, vegetables & fiber may increase the risk of certain cancers

The food addiction culprits

- Sugar, salt, fat
- The more multi sensory a food the more likely a person is to crave it
- Cold, warm, smooth, and crunchy tastes all contribute to making addictive food

Important foods that the DASH diet includes:

- Fruits and vegetables (4-5 cups)
- Whole grains
- Low-fat dairy or fortified equivalents

Digestion

The process by which food and drink are broken down into their smallest parts so that the body can use them to build and nourish cells and to provide energy

The digestive system is a series of hollow organs joined in a long, twisting tube from the:

Mouth to the anus

These organs produce digestive juices that reach the intestine through small tubes

Liver and pancreas

Peristalsis

Typical movement of the esophagus, stomach, and intestine; looks like an ocean wave moving through the muscle

Stomach

Produces digestive juices to mix up food and liquid (mixture referred to as chyme)

Ileum

Mainly absorbs water, bile salts, and vitamin B12

What digestive juice does the liver produce?

Bile

Nutrients are absorbed by which organ?

Small intestine

In the [black], proteins are broken down into [blank]

Small intestine; amino acids

Hormones that control the functions of the digestive system are produced and released by cells from where?

The mucosa of the stomach and small intestine

Cellular respiration

In the mitochondria, glucose, fatty acids and amino acids are broken down in the presence of oxygen to produce CO2, water and release energy

Salmonella

Contaminates chicken, eggs, peanut butter

Pathogenic microorganisms can cause:

Illness

Fermentation

The process of bacteria making energy from carbohydrates IN THE ABSENCE OF OXYGEN

The main end product in dairy fermentation

Lactic acid

Vegetable fermenation

Sauerkraut, pickle, kimchi

Regionally important food fermentation

Soy sauce

Body is better able to absorb [black] from yogurt than from [blank]

Calcium; unfermented milk

Viruses can survive in food, but:

Do not grow in food

Viruses cannot [blank] or form [blank] in food

Spoil; spores

Norovirus

- ~50% of all "food poisoning"
- Cruise ships outbreaks
- Resistant to most disinfectants
- Highly infectious

Bacteriophage:

Virus that infects bacteria

Make sure to always wash fresh produce properly to prevent:

Foodborne illness

Are all pickles fermented?

No

Why is vinegar used as an additive to help process certain vegetables?

The vinegar mimics the sour flavor of naturally fermented foods

Live & active cultures are maintained in yogurt by:

Cooling the yogurt to stop fermentation

E. coli O157:H7 infection may cause:

A life-threatening disease

Do most kinds of E. coli bacteria cause disease in humans?

No

What toxin does E. coli O157:H7 produce?

Shiga toxin

Listeria monocytogenes

- Multiply and survive at extreme conditions
- Low temperatures

What people are most vulnerable to listeria monocytogenes?

- Pregnant women
- Older adults
- People with weakened immune systems

Biofilm bacteria

- Difficult to remove
- Often resistant to normal sanitation procedures

Clostridium botulinum

- Spore forming foodborne pathogen
- Makes heat-resistant spores
- Dies in the presence of oxygen

Spores of C. botulinum will generally [blank] germinate and grow in foods below pH [blank]

Not; 4.8

What pH is the dividing line for spore growth?

4.6

The modes through which different microbes grow:

Bacteria: Bacterial fission
Molds: Mold spores
Yeast: Yeast budding

FATTOM

Food, Acidity, Temperature, Time, Oxygen, Moisture (conditions that affect microbial growth)

Food for pathogens

Pathogens need a source of food — especially proteins or carbohydrates, which are readily available in many of the foods you serve

Acidity for pathogens

Pathogens grow best in foods with low acidity; ingredients like lemon or tomato can make the food too acidic for rapid growth of pathogens

Time for pathogens

Pathogens need time to grow. A single bacterium can multiply to over 1,000,000,000 bacteria in 10 hours.

Temperature for pathogens

Pathogens grow best between 40F (4C)-140F (60C)

Oxygen for pathogens

- Some pathogens need oxygen
- Clostridium botulinum grow if oxygen is absent

Moisture for pathogens

- Pathogens need moisture to grow (water availability affects microorganism growth)

The "40-140 (Danger zone)" Rule

Foods should be held below 40° F or Above 140°F

Is the 5-second rule true?

No

What food safety agency inspects meat and poultry?

U.S Department of Agriculture (USDA)

What agency specializes in epidemiology?

Center for Disease Control and Prevention (CDC)

Hazard Analysis Critical Control Points (HACCP)

- Proactive & prevention-oriented program
- Mandatory for manufacturers of meat and poultry, seafood, and juice products

Food Safety Modernization Act

- It's industry's (not FDA's) responsibility to keep food safe
- Responsibility includes preventing contamination and keeping imported food safe

Organic acids are GRAS

Generally recognized as safe

Bacteriocin

An antimicrobial peptide produced by bacteria that kills other bacteria

Nisin (bacteriocin)

- GRAS status
- Commercially available as an ingredient in food
- Added to milk, cheese, sauces, and salad dressing
- Sensitizes spores to heat

Pasteurization [blank] all pathogens but not [blank]

Kills; spoilage microbes

Nonthermal process technology are [blank] to alter the nutrient content, color, or texture of a food

Unlikely

Specialists

Consume limited number of foods

Generalists (omnivores)

Consume variety of foods

Why food industries perform sensory evaluations of food?

- New food product development
- "New" and "improved" products
- Consumer testing

Appearance factors in food

Color and geometric attributes (size and shape)

Textural factors of foods

Rheology (mechanical behavior of foods)

Sensory evaluation

A scientific discipline used to evoke, measure, analyze and interpret those responses to products that are perceived by the senses of sight, smell, touch, taste and hearing

Taste (gustation)

"Chemical" sense

Most of what we perceive (or describe as taste) is actually [blank]

Smell

Taste preferences

- Genetic make-up: Has a lot to do with which tastes we find appealing & which ones we cannot tolerate
- Life's experiences: Also shape taste preferences
- Complicated: Each taste quality - sweet, sour, salty, bitter, umami - is like a separate sense

All taste preferences start in the same [blank] - the organ of taste in our tongue

Taste bud

Bitter and sour are:

"Aversive" tastes

Salty, sweet, and umami are:

"Appetitve" tastes
- Sweet = calories; a natural signal
- Salty = minerals needed for proper body functioning
- Umami/savory = taste of protein

1000s of taste buds in papillae:

- Tiny bumps on tongue
- Also on roof of mouth, throat
- Also in non-taste organs - gut, pancreas, lungs, nose

The brain [blank] the taste of the food

Detects

Eyes, ears, tongue, mouth:

All of these organs contribute to the "tastes" of foods

Smell (olfaction):

"Chemical" sense

Smell is a more "plastic" sense:

Driven by learning, experience

Aroma, flavor, texture, appearance:

All inclusive in sensory perceptions

Hot, spicy foods; cool, tingly foods:

- Meet the trigeminal nerve
1. Explains why hot, spicy foods can cause nose to run and eyes to water
2. Explains the cooling sensation of menthol
3. Explains the tingling bite of carbonation

Relating to food, which two senses tend to diminish with age?

Smell and taste

High fructose corn syrup:

55 percent fructose and 45 percent glucose

When compared to glucose, fructose contributes more to [blank] and less to [blank]

Fat synthesis; appetite suppression

Sucrose

- Table sugar
- Has about 1/2 fructose and 1/2 glucose
- Similar to high fructose corn syrup

Once digested and absorbed, [blank] from sugar is no more different than from [blank]

Fructose; high fructose corn syrup

Eliminating high fructose corn syrup will help fight obesity and health problems; only if [blank] replaced with other sugar compounds

Not

The main culprit of obesity, generally:

Too much added sugar of any kind

Artificial sweeteners

Called non-nutritive sweeteners; provide the sweetness without the calories

High-intensity sweeteners must be proven [blank] for consumption

Safe

Why do people choose to use high intensity sweeteners?

Do not contribute calories or only contribute a few calories to the diet

High-intensity sweeteners generally will [blank] raise blood sugar levels

Not

Are high intensity sweeteners safe to eat?

High-intensity sweeteners approved by FDA are safe for the general population under certain conditions of use

Sugar substitutes that are not high-intensity sweeteners:

Sugar alcohols

Sugar alcohols are primarily used to sweeten:

Sugar-free candies, cookies, and chewing gums

Two types of fats that can be detrimental to health if consumed in excess

Trans and saturated fat

Most common food allergies for children:

- Milk, eggs, peanuts, wheat, soy, tree nuts
- Most will outgrow eggs, milk, wheat, and soy

Severe allergic reaction to peanuts and/or tree nuts

Death (common)