1 Food Safety, Security, and Healthy Nutrition

A nutritious food supply is for all practical purposes unachievable without provisions for food safety and security. Nutritious foods that are safe to eat, readily available where people live, and easily accessed are fundamental needs of a healthy population.¹ A safe food supply minimizes the spread of foodborne illnesses and contributes to the health and productivity of a community.² Reliable access to affordable food reduces nutrition-related disease and supports a healthy lifestyle.

Foods arrive at our tables through a complex, interconnected system that is increasingly global. It’s quite likely that the foods you ate today were produced, processed, distributed, and prepared somewhere else in the country or world.³ As food markets become increasingly intertwined, the risk of contamination and novel foodborne illness grows.⁴ A local outbreak can originate in any part of the world and involve familiar microorganisms or exotic agents transported to the neighborhood by a global supply network.

There are a variety of diseases carried by food and drink, including those caused by bacteria, viruses, parasites, allergens, and toxins. To avoid foodborne illness, the best strategy is to understand microorganisms and their relationship to the food supply. Good food purchasing and handling practices reduce the risk of foodborne illness. Personal hygiene and environmental cleanliness are important. Cook food to destroy bacteria and parasites. Reheat food carefully.

As described in Healthy People 2020, food insecurity negatively impacts health and increases disease risk. The place (environment and setting) where people live and work sometimes has constraints that limit access to safe, nutritious food.⁵ This is a significant public health concern.

Objectives

• Recognize organisms that cause foodborne illness
• Recommend safe food-handling practices
• Describe bacterial needs for growth and multiplication
• Describe viruses and parasites that contaminate food
• Recognize food insecurity among college students

1.2 Understanding Foodborne Illness

Overview

Do you believe that unprocessed foods taste better or retain more health benefits? Thinking about eating raw oysters or drinking raw milk? Although tasty and attractive, raw foods are not risk-free. A dangerous consequence of consuming raw foods is an increased risk of food-related illness. Raw oysters and clams have been linked with outbreaks of hepatitis A, undercooked eggs with salmonella, and unpasteurized apple juice with E. coli O157:H7.

As the local, state, and regional marketplaces become more global, so does the food supply. Foods that are harvested, held, and transported far from their places of origin are repeatedly exposed to potential contaminants. Centralized production and distribution spread any contamination to large numbers of people across both state and national lines. As a result, an outbreak of foodborne illness can originate in any part of the world, cover larger geographic areas, and involve more pathogens.

Key Concepts

• Types of foodborne illness
• Food-handling practices that prevent foodborne illness
• Assessing level of risk
• Common organisms that cause foodborne illness

Defining Foodborne Illness

Foodborne illness is a disease that is transmitted through contaminated food or drink. More than 250 different types are known, with infections and intoxications from bacteria, viruses, and parasites causing the most common illnesses. Chemicals and other harmful substances that contaminate food also cause poisonings. There is no one way to characterize a given foodborne illness. Each has a unique set of symptoms. As the gastrointestinal tract is the point of entry, it is not surprising that the first signs of foodborne illness often are nausea, vomiting, abdominal cramps, and diarrhea.

When the same food or drink makes two or more people ill, the US Food and Drug Administration (FDA) declares a foodborne illness outbreak.⁶ The US Centers for Disease Control and Prevention reports that over seventy million cases of foodborne illness occur annually. Common culprits are campylobacter, salmonella, and E. coli O157:H7 bacteria and noroviruses, single-stranded RNA viruses that cause acute stomach distress. Other diseases that are sometimes but not always carried in food include shigella (bacteria), hepatitis A (virus), Giardia lamblia, and cryptosporidia (parasites).

Foodborne illness symptoms include upset stomach, stomach cramps, nausea, vomiting, diarrhea, fever, and dehydration. Agents that typically cause foodborne illness include bacteria, viruses, parasites, molds, toxins, contaminants, and allergens.

Preventing Foodborne Illness

The best strategy for reducing the risk of foodborne illness is to understand disease agents and their relationship to the foods that you eat. Generally speaking, bacteria grow and multiply in foods, while viruses do not. It usually takes a minimum number, or bacterial load, to cause illness. This number varies based on the type of bacteria and a person’s age and health status. Conversely, the presence of any virus, even a small number, has the potential to cause illness. Of these two microorganisms, bacteria are by far the largest contributor to outbreaks.

Foods that are likely to support pathological bacteria are called Potentially Hazardous Foods (PHFs). These foods tend to be rich in protein, carbohydrates, and/or water. PHFs include foods high in protein, like custard pies and meat sandwiches, or high in carbohydrates, like potato salad and rice pudding. These foods must be handled with care to prevent contamination with a disease-causing agent as well as to prevent subsequent bacterial growth.⁷

For more information on foodborne illness, go to the Food Safety Information Gateway at https://www.foodsafety.gov/.

Only a small number of all bacteria are pathogenic, and the risk of illness is dose dependent. Risk increases as the number of bacteria contaminating the food or drink grow until it reaches a point where getting ill is inevitable. How you handle and prepare your food determines the potential for bacterial growth and, ultimately, your risk of illness.

Level of Risk

How you handle and prepare your foods contributes to your risk of illness by increasing or decreasing the risk of contamination. Not all people are equally susceptible to the same bacterial load. The infective dose, or the number of microorganisms required to make an individual ill, is dependent upon the vigor of the immune system.

Due to compromised, or less effective, immune systems, the following groups have a higher risk at lower doses than the general population: the elderly, those undergoing cancer treatment, those who are post–organ transplant and taking immunosuppressant agents, infants and young children who do not have fully developed immune systems, those with HIV or AIDS, those with liver diseases or diabetes, and pregnant women.

Bacteria

Only a small number of all bacteria are pathogenic, or agents that cause foodborne illness. Bacteria responsible for recent illness outbreaks include campylobacter, salmonella, shigella, Clostridium perfringens, staphylococcus, E. coli, streptococcus, Bacillus cereus, Listeria monocytogenes, vibrio, and Yersinia enterocolitica.

These bacteria use food as a source of energy and protein to fuel growth and reproduction. The longer a contaminated food item is held under conditions that favor the growth of these organisms, the greater their number. At some point, the number present (also called the dose or bacterial load) is enough to make all of those who consume the food ill, regardless of state of health.

Viruses

A virus is the smallest known microbe. It has a core of genetic material (DNA or RNA) and a protective protein coat called a capsid. Some viruses have an additional outer layer called the envelope. A virus attaches to a host cell and enters it to usurp the cell’s internal workings. Once in control, the virus begins replicating its own genetic material. Replicated virus particles use the cell’s membrane as an envelope as they bud or burst out of the invaded cell.⁸

Norovirus is a common cause of foodborne illness in the US It is transmitted both in foods and person-to-person. Hepatitis A is another virus that is carried by contaminated food and water.

Parasites

Parasites are organisms that require a host to complete their life cycle. The prevalence of parasitic infections in the US has decreased as agricultural practices have improved and water treatment has become common. Incidences of trichinosis (found in pork) dropped in the US as infections among farm animals were greatly reduced. Special Collections of the USDA National Agriculture Library details the work done to eliminate trichinosis in the country (https://www.nal.usda.gov/exhibits/speccoll/exhibits/show/parasitic-diseases-with-econom/parasitic-diseases-with-econom/trichinosis/trichinellosis—trichinosis-t).

Infections with other parasites, such as Anisakis (found in fish) and tapeworm, have grown. Seafood safety at https://www.seafoodhealthfacts.org/seafood-safety/general-information-patients-and-consumers/seafood-safety-topics/parasites recommends cooking fish to a minimum internal temperature of 145°F for fifteen seconds, which destroys parasites and prevents illness. Eating raw or inadequately cooked meat carries a risk of intestinal infection with tapeworm (taeniasis). The World Health Organization at https://www.who.int/news-room/fact-sheets/detail/taeniasis-cysticercosis describes tapeworms as a leading cause of disability and death in countries where it is endemic.

Summary

How we acquire and prepare our food moderates our exposure to foodborne illnesses caused by bacteria, viruses, parasites, or chemicals. Bacteria are the largest contributors to foodborne illness and preferentially grow and multiply in potentially hazardous foods. The capacity of the immune system influences susceptibility to foodborne illness, and certain segments of the population are at greater risk than others. Viruses are small microbes that convert the machinery of an invaded cell to replicate. Parasites use living hosts to complete their life cycle and rely on poor sanitation practices to find hosts.

1.3 Food Safety and Pathological Bacteria

Overview

Bacteria are adaptable and, depending on conditions, can exist in an active, growing state, called vegetative, or a hibernation state, called spore. To enter the vegetative state, seven needs must be met: (1) a desirable temperature for growth and reproduction; (2) enough moisture to carry out life processes; (3) sufficient nutrients; (4) an adequate amount of time to adapt, grow, and reproduce; (5) the absence of competing bacteria; (6) the proper pH (acid or alkaline); and (7) the presence or absence of oxygen, depending on the type of bacteria.

Key Concepts

• Vegetative and spore state of bacterial life
• Seven needs for active bacterial growth
• Four-stage bacterial life cycle
• Handling food to minimize bacterial contamination and growth

Vegetative or Spore State

Bacteria are versatile and adaptable. When the seven needs are met, conditions favor growth, and bacteria enter a vegetative state. When some or all of the seven needs are not met, conditions do not favor growth, and bacteria adapt by entering a spore state. In the vegetative state, bacteria are reproducing, and total numbers are increasing, making contaminated food more dangerous to eat. In the spore state, bacteria are quietly surviving adverse conditions. Numbers do not increase as they wait for a more favorable environment.

What’s a good defense against vegetative bacteria? Cooking your food! Bacteria in this state are vulnerable to high temperatures, and heating food kills any that contaminates it. Cooking food decreases or eliminates the absolute amount of pathological bacteria, driving it down to a point where your immune system is not seriously challenged and you will not become ill.

In the spore state, bacteria are very resistant to both high and low temperatures. It is important to never allow conditions to develop where spore state bacteria convert to a vegetative state and begin to grow and multiply. Freezing food, for example, does not destroy spores but prevents growth and multiplication. Time and temperature are linked. Exposing food that supports bacterial growth to favorable temperatures is dangerous and should be kept to a minimum amount of time.

Four-Stage Life Cycle

After contaminating a food source, a colony of bacteria goes through a four-stage life cycle. This life cycle is like a flattened bell curve and represents changing rates of bacterial reproduction and multiplication. Initially, the colony experiences a lag phase where adaptation to a new environment takes place.

At this point, the absolute number of bacteria is modest and does not pose a threat of illness for most people. As the adaptive phase is passed and the rate of multiplication increases, the colony experiences a period of rapid growth called a log phase. A colony of pathological bacteria at this stage poses a threat to human health.

Practice food-handling strategies that do not allow a bacterial colony to reach the log phase. Your best defense is to limit opportunities for an initial bacterial contamination of your food and control the temperatures at which you store and prepare foods to avoid the growth of any bacteria that might contaminate them.

Pathological bacteria grow best at or near body temperature. Holding food at “room temperature” approaches the optimal range and allows the bacterial growth rate to reach dangerous levels. It is best to avoid holding foods at temperatures within approximately 50°F above or below body temperature.

“Keep cold foods cold and hot food hot” is sound advice!

Time and Temperature

Watch the clock! Anytime food is exposed to temperatures between 40°F and 140°F, it is in the TEMPERATURE DANGER ZONE, a range where the bacterial growth rate accelerates and the potential for foodborne illness increases. Keeping the amount of time that food is in the danger zone to a minimum is a good practice. The US Department of Agriculture reminds us that foods are not safe to eat if they are held in the temperature danger zone for more than two hours or for one hour if ambient temperatures are >90°F.⁹

The last two phases of growth in a bacterial colony are stationery and decline. At the STATIONARY phase, enough bacteria are present to make most people ill, but the rate of bacterial reproduction has decelerated. The colony has depleted available resources, such as water and nutrients, and competition among the bacteria has increased. As more bacteria die than reproduce, the DECLINE phase begins.

Moisture

In addition to time and a desirable temperature, a bacteria colony needs a sufficient amount of moisture. The “availability of water” is called water activity and is expressed as “aw”. Available water is not bound by food molecules and can be used by bacteria to support growth.¹⁰

A food with a water activity over 0.86 has sufficient free water present to support bacterial growth.10 Distilled water has a water activity of 1.0; ground meat, 0.98; and dry egg noodles, 0.5. The water activity of food can be lowered by freezing it, dehydrating it, dropping its pH, or mixing it with a dissolved substance like sugar or salt.

Over the ages, diverse peoples have reduced water activity to preserve food. Pork was salted, and berries were made into jam. In the Andes, sliced potatoes were freeze-dried by exposure to wind and cold, and in Northern Europe, cod was air-dried on racks. As long as dehydrated foods are kept dry, bacterial growth is halted, and the foods are preserved. If moisture should become available, bacterial growth resumes.

Acid or Alkaline

Pathological bacteria grow best in an environment that is neutral or slightly acidic and have a preferred pH range of 4.6 to 9.0. The pH scale tells us if an aqueous solution is acidic or basic, and it ranges from 0-14. A pH of 7.0 (distilled water) is neutral, while a pH below 7.0 is acidic, and one above 7.0 is alkaline.¹¹ Limes, with a pH of 2.0, are acidic and do not readily support bacterial growth. Fresh pork, on the other hand, with a pH of 6.4, easily supports bacteria. Most bacteria will not grow well if the pH is below 4.6 or above 11.

A traditional food-preservation technique that takes advantage of a low pH is the use of a brine solution, such as pickling, or by fermenting the food.

Oxygen Yes or No

Bacteria vary in their need for oxygen. Microorganisms called aerobes must have oxygen present for growth, while those called anaerobes grow in low oxygen or when oxygen is absent. Facultative bacteria can adapt and grow whether oxygen is present or not.

Canning is a method of food preservation that makes shelf-stable (room temperature) storage of food possible. Food in a sterile, sealable can is heated to a temperature that destroys bacteria. During the heating process, oxygen is driven from the can, creating a low-oxygen (anaerobic) environment.¹²

Historically, home canning was a source of botulism poisoning when the canning process was inadequate. Clostridium botulinum grew in the anaerobic environment of the can and produced a deadly toxin. After opening a home-canned food, you should boil the food for at least ten minutes to destroy any toxin.¹³ The US Centers for Disease Control and Prevention (CDC) provides information on home canning and how to prevent botulism poisoning at https://www.cdc.gov/foodsafety/communication/home-canning-and-botulism.html.

While the most desirable goal is to prevent contamination of our foods by pathological bacteria, we must assume the potential exists and handle our foods in ways that prevent growth. The bacteria that cause most of the foodborne illness in the US are listed below. Learn more about them at the CDC “Foodborne Germs and Illnesses” web page: https://www.cdc.gov/foodsafety/foodborne-germs.html.

• Campylobacter
• Clostridium perfringens
• Listeria
• Salmonella
• Staphylococcus aureus
• E. coli
• Clostridium botulinum
• Vibrio

Summary

Bacteria sometimes contaminate our food. The way we handle and prepare it influences our risk of foodborne illness. Bacteria exit in two states, and infective potential is greater during a vegetative state of growth and multiplication. Conversely, the spore state is one of reduced growth and dormancy. Bacteria growth has four stages, and keeping bacteria in the early lag phase limits multiplication.

Pathological bacteria grow and multiply in temperatures between 40°F-140°F. Holding food in this temperature range should be avoided. These microorganisms grow best in a neutral or slightly acidic medium. Recognizing this, people have used acids, like vinegar, to lower the pH as a method for preserving food. A dangerous toxin is produced by C. botulinum, an anaerobic bacterium that grows when food is improperly canned.

1.4 Viruses, Parasites, and Foodborne Illness

Overview

Viruses are microscopic agents that cannot replicate themselves outside a living cell. Viruses do not replicate in food but use it as a carrier, or method of transportation, to a host. An infected person can unintentionally transmit norovirus or hepatitis A to food during preparation and serving, so it is important to prevent contamination by following food safety guidelines. Stability of viruses that typically are transmitted in food or water depends on food composition, viral concentration, and temperature. Boiling temperatures used in cooking destroy most viruses.

Parasites are microscopic organisms that require a host to complete their life cycle. Incidences of trichinosis (found in pork) have dropped in the US, while infections with other parasites, such as Anisakis (found in fish) or tapeworm (found in meat), have grown more common. These trends reflect changes in agriculture practices as well as globalization of the food supply. Cooking foods to a minimum internal temperature of 160°F destroys parasites and prevents illness.

Key Concepts

• Viruses and foodborne illness
• Parasites that contaminate food and drink
• Food-handling practices that minimize risk
• Viruses and foodborne illness
• Parasites that contaminate food and drink
• Food-handling practices that minimize risk

Viruses of Concern

In terms of foodborne illness, viruses of concern include Norwalk-like virus, Rotavirus, astrovirus, noroviruses, and hepatitis A. Viruses cause illness at very small doses, and any contamination of the food supply presents a risk of foodborne illness. Frequently, the original source of contamination is an infected person who has poor personal hygiene when handling, preparing, or serving food. Occasionally, a water supply becomes contaminated due to problems with a sewage system or a heavy rain causing excessive runoff. Molluscan shellfish (oysters, mussels, and clams) harvested from contaminated waters are sources of disease-causing viruses.

Viruses Transmitted in Food

A viral transmission in food is likely a result of poor hygiene practices by someone handling the food or poor sanitation at a food-processing plant.^14,15 It’s rare but not impossible for a virus to transmit from animal to human in uncooked meat.

Gastroenteritis, an inflammation of the intestinal wall, is caused by noroviruses. Sometimes called the stomach flu, it’s one of the most common illnesses in the US. Contamination of food with norovirus typically happens when someone preparing a meal is infected.

Another example of a viral disease transmitted by food is hepatitis A, which is characterized by inflammation of the liver. Symptoms include fever, nausea, abdominal pain, fatigue, and jaundice. Symptoms may not appear until fifty days after infection, making it difficult to trace the source. Hepatitis A is found in the feces and urine of infected people who contaminate food and water that is subsequently consumed by others.¹⁶

The viability of viruses contaminating foods is influenced by the type of food, the number of virus particles contaminating it, and the temperature at which the food is held. Cold temperatures tend to extend the period of viability. Heating may inactivate or destroy some viruses, like Norwalk, but not others, like hepatitis A. The higher the temperature, the greater the inactivation, and boiling appears to destroy most viruses.

Parasites

Parasites are microscopic organisms that require a host to complete their lifecycle. People become hosts when they consume foods that contain either live larvae or parasite eggs. Trichinella spiralis, a roundworm transmitted by pigs, rats, and wild game, is one of the best-known parasites.¹⁷

Since the early 1900s, when one out of six people were infected with parasites, the number of cases in the US has steadily declined due to improved farm management practices and public awareness that fresh pork should be cooked to a minimum of 145°F. The odds of acquiring trichinosis today are quite small. Freezing and curing pork products and adequate cooking at home reduce the potential of infection.

Beef and hog tapeworms (taenia) infect people and cause foodborne illness. People host the adult stage and pass ova, or eggs, in feces, which contaminate fields where farm animals graze and ingest them. In the past, meat was called “measly” when highly infested with larva from a beef tapeworm, Taenia saginata. Good sanitation practices, including sewage treatment, prevent the completion of the life cycle and reduce risk of illness.

Anisakis is a nematode that contaminates fish. People living in Japan and the Netherlands have a higher incidence of this foodborne illness due to widespread consumption of fish. Symptoms include irritation to the throat and digestive tract that occurs when larvae attach. Prolonged freezing and adequate heating kill the larvae. Eating raw fish is not recommended! Learn more at the CDC web page: https://www.cdc.gov/parasites/.

Parasites of interest that threaten to contaminate our food include the following:

• Giardia lamblia
• Cryptosporidium parvum
• Toxoplasma gondii
• Cyclosporiasis
• Anisakiasis
• Trichinella spiralis

In some cases, freezing food to temperatures below ?4°F for seven or more days destroys the parasite. To confidently prevent a parasitic illness, cook foods that are likely carriers to a temperature above 160°F to kill both larvae and eggs.

Summary

Viruses are microscopic agents that cause illness when they enter our bodies through contaminated food or water. Contamination usually happens during preparation or service when someone handling food is infected or when untreated sewage mixes with drinking water. Viruses need a host cell to replicate and make more virus particles. This process damages and destroys body cells. Sometimes called the stomach flu, norovirus causes gastrointestinal distress. Hepatitis A, a virus found in feces and urine, also causes foodborne illness.

Advances in agricultural practices and modernized water treatment have greatly reduced the risk of parasites contaminating our food. Some foods, such as raw fish and undercooked meats, still pose a risk of illness, as Anisakis in fish and tapeworm in raw meat are transmitted to people when foods are undercooked. The US Department of Agriculture and the Centers for Disease Control and Prevention provide guides and charts that help people understand foodborne illness and how to use safe food preparation and cooking methods to reduce risk.

1.5 Food Safety and Shopping

Overview

We play an important role in minimizing our own risk of foodborne illness. How? By following best practices for buying, storing, preparing, and serving food and drink in our homes. The US Department of Agriculture provides safe food-handling fact sheets covering a range of topics, including how to safely thaw frozen meats, cooking in a microwave oven, and how to prevent cross-contamination^18,19 (https://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets/safe-food-handling).

Key Concepts

• Planning a safe food-shopping trip
• Personal hygiene and home safety practices
• Home food safety—thawing, cooking, serving, and reheating

Shopping with Safety in Mind

As of August 2020, the US Centers for Disease Control and Prevention found no evidence that COVID-19 was spread by food.²⁰ The risk that someone gets infected by touching a food or its package is low. Why? The coronavirus is spread from one person to another through respiratory droplets. Although surface contamination is possible, hand washing with soap and water minimizes this risk for COVID-19, just like it does for other viruses. Learn more at https://www.cdc.gov/coronavirus/2019-ncov/daily-life-coping/food-and-COVID-19.html.

Shop at reliable markets with established food safety and sanitation practices. The Texas Department of State Health Services licenses and inspects food service establishments to ensure that operators follow safe food-handling rules and minimize risk of foodborne illness.²¹

As you walk through the grocery store, think about the perishability of each item in terms of temperature sensitivity and ease of damage. Plan your shopping to avoid damage to delicate items such as tomatoes and peaches or unnecessarily extending time in the temperature danger zone for refrigerated and frozen items.

Inspect packaged foods by looking for intact packaging and avoid cans that are dented, cracked, or bulging. Contain drippings from raw meats, poultry, and fish to avoid cross-contamination with other foods in your cart, particularly those that will not be cooked. At the grocery store, bag meats separately.

Frozen foods should be solidly frozen and purchased at the end of a shopping trip to avoid thawing during transport. If fruits and vegetables are to be eaten raw, avoid those that have been excessively handled by other shoppers. Juices, milk, and cheese should be pasteurized. Use perishable foods over a short period of time, preferably less than a week. Take all foods home immediately after purchase and, if necessary, refrigerate.

Safe Food Handling at Home

Personal hygiene and environmental cleanliness are critical during food preparation. Outbreaks of foodborne illness are often tracked to an infected individual who failed to follow good sanitation practices while preparing food. Before you handle foods and after touching any raw meat, fish, poultry, or eggs, clean your hands using soap and water. Lather up and scrub for at least twenty seconds with special attention given to fingernails.

To prevent chemical contamination, remove all detergents, cleaners, insect sprays, and bleaches from areas where food is prepared. Clean all surfaces, including counters, sinks, and tables, using a clean cloth and hot, soapy water followed by a diluted sanitizer, such as bleach. The US Centers for Disease Control and Prevention recommends five tablespoons of bleach per gallon of room temperature water. Cutting boards should be washed and sanitized as well. Use a different cutting board for produce than for raw meats. Learn more at https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/disinfecting-your-home.html.

Thawing and Cleaning Food

Thawing frozen foods at room temperature is not the best method. Plan ahead and remove foods that require thawing, such as poultry, meat, or fish, from the freezer a day in advance, and place them in a pan near the bottom of the refrigerator. This technique maintains a temperature of 40°F or less and minimizes exposure to contamination. If there is no time for refrigerated thawing, use cold running water in a sink where the water can drain or thaw quickly in the microwave oven. It is important to remember that foods thawed outside the refrigerator must be used immediately and not placed back in the refrigerator for later use.

Fresh produce (fruits and vegetables) should be washed prior to use to remove surface soil and bacteria. If necessary, use a clean vegetable brush to remove visible soil. As food ages, fungi sometimes grow and become visible as mold.

Molds can grow at refrigerator temperatures and spoil fruits, vegetables, meats, cheeses, and breads. You can detect molds by looking for changes in food color and texture, but don’t smell or taste it. If mold is found on cheese bricks or blocks, cut and discard the part of the block that is located at least one inch from visible mold. Mold toxin, called aflatoxin, cause allergic reactions, nervous system disorders, and kidney and liver damage. Discard any questionable moldy food! Learn more at https://www.fsis.usda.gov/shared/PDF/Molds_on_Food.pdf.

Cooking and Serving Food

Foods that are served hot should be cooked thoroughly and held at temperatures above 145°F. A temperature of at least 165°F ensures that adequate heating has taken place. It is a good idea to have a clean stem thermometer available to measure temperature. Leftovers should be quickly cooled and reach an internal temperature of 40°F or lower within two hours.²² During cooking, serving, and cooling, all foods should be protected from contamination. Use a clean plate for cooked meats; don’t reuse a plate that held raw meat. Learn more at https://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets/safe-food-handling/safe-minimum-internal-temperature-chart/ct_index.

Use leftovers within a few days and avoid any opportunities for cross-contamination. Rapidly reheat any cooked, leftover food to an internal temperature of at least 165°F. Reheat gravy or soups to a vigorous boil. Keep cold or refrigerated food at or below 40°F, or discard after two hours at room temperature. Do not use any foods that look or smell spoiled or decayed. When in doubt, throw it out!

Summary

Food safety starts with us, the consumers. When we plan our shopping trips to minimize time in the store, separate perishable items and raw meats in our carts, and select foods with intact packaging, we start from a food safety perspective. Storing, cooking, and serving foods are all points where our food safety practices minimize the risk of contamination and decrease the potential for bacteria growth. Adequately cooking foods destroys microorganisms and makes our foods safe.

1.6 Food Security and Healthy Nutrition

Overview

Food security is best achieved when the food system is sustainable. A sustainable food system has provisions for economic stability through profit from growing, processing, transporting, and distributing food. It also benefits the whole of a society without undue harm, and it protects the environment. The World Health Organization proposes four components of food security: (1) availability, (2) access, (3) utilization, and (4) stability. These components are recognized as critical factors in providing a safe, reliable source of healthy food to all people.

The US Department of Agriculture tracks food security and reports on household status by category: (1) high food security, (2) marginal food security, (3) low food security without hunger, and (4) very low food security with hunger. Most people would recognize categories 3 and 4 as describing food insecurity. Food must be affordable. Availability, accessibility, and cost impact affordability. Some students experience food insecurity while attending college, as financial aid and work income fall short of meeting daily needs. To alleviate the problem, colleges and universities open food pantries and link students to community food resources.

Key Concepts

• Food security and sustainable food systems
• Four components of food security
• Prevalence of food insecurity in US households
• Food insecurity among college students
• Food affordability during college

A Right to Food

Is there a right to food? A recent publication of the United Nations Committee on World Food Security (http://www.fao.org/3/ca9733en/ca9733en.pdf) says yes: the article lays out a legal framework for a right to food through sustainable food systems.²³ A sustainable food system meets the needs of today without compromising the ability of future generations to meet their needs.

A sustainable food system allows for economic stability through profit, benefits the whole society (social stability), and has a positive or neutral impact on the environment (environmental stability).²⁴ Sustainable farming is recognized as a sound strategy for ensuring long-term productivity while meeting intensifying world food demand. Consumers, particularly those in developed countries, make food choices that ultimately drive farming practices.

In the Food, Agriculture, Conservation, and Trade Act of 1990, US Congress described sustainable agriculture as an integrated system of plant and animal production practices that achieves five goals: (1) to satisfy the need for food and fiber, (2) to enhance environmental quality and the natural resource base, (3) to efficiently use both nonrenewable and on-farm resources, (4) to sustain the economic viability of farm operations, and (5) to enhance the quality of life for farmers, workers, and society.²⁵

As consumers in a global marketplace, our shopping signal the food system, as purchases send messages to farmers who decide which crop to plant or animal to raise. Preferences for specific shapes, colors, and sizes set unintended patterns that are reinforced in the food supply. Awareness of the role that we play in shaping the food system builds a more sustainable future.

Components of Food Security

The World Health Organization (http://www.emro.who.int/nutrition/food-security/) describes four components of personal and community food security: (1) availability, (2) access, (3) utilization, and (4) stability.²⁶ A food-secure person or household comfortably meets all four criteria. There is nutritious food in their community, and they feel confident that they can get it.

Availability is a place (environment or setting) where sufficient quantities of food are consistently available. Access acknowledges that adequate income and resources are necessary for buying or growing food. Utilization focuses on safe food-handling practices throughout the food system and in the home. Stability is the continued availability and accessibility of food regardless of the season or unexpected crises.

The USDA Economic Research Services conducts research on food security in US households and communities. It defines food insecurity as a household economic and social condition of limited or uncertain access to adequate food. The US Census Bureau defines a household as all persons living in one housing unit, and unrelated roommates sharing a living space are considered a household. College students renting an apartment together are a household.

Periodically, the USDA publishes food availability reports that track levels of food security (https://www.ers.usda.gov/topics/food-nutrition-assistance/food-security-in-the-us/). The reports categorize food security as (1) high food security, (2) marginal food security, (3) low food security (without hunger), and (4) very low food security (with hunger).²⁷ Categories 3 and 4 are what most people would think of as food insecure.

Household Indicators of Food Insecurity

• Worried food would run out
• Food bought did not last
• Could not afford balanced meals
• Cut or skipped meals
• Cut or skipped meal in three or more months
• Ate less than felt should
• Hungry but did not eat
• Unplanned weight loss
• Did not eat whole day
• Did not eat whole day, three or more months

Food-Insecure College Students

Food-insecure college students are not on the fringe but represent a diverse group that is challenged with meeting health needs while attempting to learn. Food insecurity is a complex structural problem often related to a lack of money and is unequally distributed among students.²⁸

A community college student is more likely to be food insecure than a student attending a four-year university. International students who rely on campus services that close during breaks or who lack transportation also are at risk. First-generation students, older students, veterans, those working and commuting, and students from the foster care system are all are more likely to experience food insecurity.²⁹

What is it like to be food insecure during college? Some students report going a whole day without eating, while others describe skipping meals, eating less, and cutting portions.³⁰ Martinez et al. defined food insecurity among college students as a lack of socially acceptable ways to access safe, nutritionally adequate foods.³¹ Henry characterized it as reduced caloric intake, lack of access to healthy food, lack of dietary variety, hunger without eating, or reduced weight due to not consuming enough calories.³² In Henry’s 2017 study, students discussed it as constantly searching, worrying, and wondering about food.

How Are Food-Insecure Freshmen Different?³³

• Higher incidence of depression
• Less likely to eat breakfast
• More likely to have unhealthy off-campus meals
• Less likely to get food from parents

How Do Students Deal with Food Insecurity?³⁴

• Eat cheaper, less nutritious foods
• Skip meals
• Prioritize thinking about the next meal above schoolwork
• Avoid social events where money is needed for food

In a 2018 report of food insecurity among college students, Urban Institute found that 11.2 percent attending four-year institutes and 13.5 percent attending vocational schools experienced insecurity.³⁵ Urban Institute further reported that students under the age of twenty were less likely to face food insecurity, while those thirty years and older were more likely to experience it.

Food Affordability for College Students

What factors impact food affordability?

• Availability
• Accessibility
• Cost

An affordable eating pattern happens when people have the money and they need to purchase healthy foods that align with dietary guidelines and reduce the risk of obesity and disease. As the cost of attending college has risen, the gap between financial aid and daily expenses has grown. Students depending on financial aid sometimes find themselves in an untenable position: pay college expenses (tuition, housing, books, etc.) or buy food.^36,37 Colleges and universities are taking steps to address student food insecurity by stocking food pantries and connecting students to local food banks. Many universities have curbside pickup and links to county food resources.

Summary

A sustainable food system is a public health goal that benefits our society. An outgrowth of a sustainable system is greater food security for all people. Food must be available in the local community, readily accessible, and utilizable (safe and nutritious). The food supply must be reliable and resistant to disruption. Food insecurity impacts a wide range of people at all stages of life. College students are at risk when financial aid and income fall short of daily needs. Food insecurity adversely affects learning and engagement in social activities. As a response, colleges and universities have opened on-campus food pantries and provided links to community resources.

References

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