食源性疾病
67 道题Whole, uncut melons are protected by an intact rind and are not time/temperature control for safety food. Once a melon is cut, the knife carries surface organisms into moist, low-acid flesh, so cut melon is. Cooked rice and cut tomatoes are also on the list because heat treatment or cutting removes their natural barriers.
Cut leafy greens are time/temperature control for safety food, so shredded romaine must be held at 41°F or below like any other TCS item. Cutting releases plant fluids and spreads field organisms across every leaf surface, which is why whole heads are far more stable than a bin of shredded lettuce.
Untreated garlic-in-oil is a classic botulism hazard: the oil seals out oxygen while the low-acid garlic supplies nutrients, which is exactly what Clostridium botulinum needs to produce toxin. The mixture must be kept cold and used quickly, or the recipe must be acidified under a variance from the regulatory authority.
A baked potato is time/temperature control for safety food, so it must be held at 135°F or above or cooled and held at 41°F or below. Foil traps heat and blocks oxygen around a low-acid food, which is the combination that has caused botulism outbreaks from foil-wrapped potatoes held at room temperature.
FDA Food Code §3-501.16An intoxication makes people sick quickly, often within one to six hours, because the toxin is already in the food when it is eaten. Infections need time for the organism to multiply in the body: hepatitis A takes weeks, Listeria can take days, and parasites are slower still, so a three-hour onset points to a toxin.
Histamine builds up when scombroid fish such as tuna, mahi-mahi, and bonito are time-temperature abused, and it is a heat-stable chemical rather than a living organism. Cooking, freezing, and rinsing all leave it intact, so the only controls are buying from a reputable supplier and keeping the fish cold from the moment it arrives.
Ciguatera toxin accumulates in large predatory reef fish such as barracuda, grouper, and amberjack, and it survives cooking, freezing, and acid marinades. Because there is no kill step in the kitchen, the control is purchasing from suppliers who comply with law and avoiding fish from unapproved sources.
FDA Food Code §3-201.11An outbreak is an incident in which two or more people experience the same illness after eating the same food, and it is confirmed when a laboratory analysis identifies the source. A single complaint, a recall, and an inspection violation are all serious signals, but none of them meets the definition on its own.
Highly susceptible populations are people more likely to become seriously ill, served in facilities that provide custodial care such as day cares, hospitals, nursing homes, and senior centers. Bars, food trucks, and banquet restaurants serve the general public, so the stricter rules on raw eggs, raw sprouts, and undercooked animal food do not apply to them.
FDA Food Code §3-801.11In a facility serving a highly susceptible population, pasteurized eggs or egg products must be substituted for raw eggs in dishes such as Caesar dressing, hollandaise, mayonnaise, meringue, and eggnog, and in any recipe combining more than one broken egg. Cold holding, a grading stamp, or a short service window does not remove the Salmonella risk from a raw egg.
FDA Food Code §3-801.11An operation serving a highly susceptible population may not serve raw seed sprouts in ready-to-eat form, because sprouting conditions are ideal for Salmonella and E. coli and no wash step reliably removes them. Washed vegetables and properly cooled cooked legumes are acceptable at the same temperature.
FDA Food Code §3-801.11Both viruses are shed in feces and reach guests when an infected food handler touches ready-to-eat food, which is why handwashing and the no-bare-hand-contact rule are the primary controls. Undercooked beef points to E. coli, allergen cross-contact is not an infection at all, and fish toxins are chemical hazards.
FDA Food Code §3-301.11Salmonella Typhi is carried by people, and a carrier can shed the organism in feces long after symptoms end, which is why the Food Code makes typhoid fever reportable for three months after diagnosis. Nontyphoidal Salmonella is the one associated with poultry and eggs, Vibrio with coastal waters, and Clostridium species with soil.
In a toxin-mediated infection the guest swallows living bacteria, which then produce toxin in the intestines. That is different from an intoxication such as Staphylococcus aureus, where the toxin is formed in the food beforehand, and it is why cooking ground beef to 155°F for 17 seconds prevents the illness.
Mushroom toxins are heat stable and a misidentified wild mushroom can be fatal, so cooking and freezing are not controls. All food must come from sources that comply with law, and a personal waiver does not make an unapproved source legal or a poisonous mushroom safe.
FDA Food Code §3-201.11Food prepared in a private home may not be used or offered for human consumption in a food establishment, because a home kitchen is outside the regulatory system that inspects suppliers. Reheating, labeling, and tasting do nothing about an unapproved source, and this rule is absolute regardless of how good the cook is.
FDA Food Code §3-201.11The five risk factors are purchasing food from unsafe sources, failing to cook food adequately, holding food at incorrect temperatures, using contaminated equipment, and practicing poor personal hygiene. They are worth memorizing because a food safety management system is judged on whether it controls these five, not on how clean the dining room looks.
污染与过敏原
58 道题The three categories of food contamination are biological (pathogens such as bacteria, viruses, and parasites), chemical (cleaners, sanitizers, pesticides, toxic metals), and physical (foreign objects such as glass or metal). Bacteria, viruses, and parasites are three subtypes of the single biological category, not three categories of their own. Hot-held, cold-held, and frozen are holding methods, and natural/artificial/processed are labeling terms; neither set names a hazard.
A cleaning chemical stored above food creates chemical contamination if the degreaser leaks, drips, or splashes onto the onions. Chemicals must be kept in a separate area, below and away from food, utensils, and single-service items (FDA Food Code §7-201.11). Nothing here involves a pathogen, so it is not biological contamination; nothing involves a foreign object such as glass or metal, so it is not physical contamination; and degreaser is not one of the Big 9 allergens, so allergen cross-contact does not apply. Each option names a real control, but only one names the hazard this storage error creates.
A foreign object such as glass, a metal shaving, a bandage, or a bone is physical contamination. Managers control it by keeping equipment and light shields in repair, never using glassware to scoop ice, and inspecting produce. Biological contamination means a living pathogen, chemical contamination means a cleaner, pesticide, or toxic metal, and allergen cross-contact means an allergen protein moved into a food that should not contain it; a glass shard is none of those. Every option names a genuine control, so the question is only which hazard category the glass falls into.
Cross-contamination is the transfer of pathogens from one food or surface to another, such as raw poultry juices dripping onto ready-to-eat produce or using the same unwashed cutting board. Storing raw meats below ready-to-eat foods and using separate color-coded equipment prevent it (FDA Food Code §3-302.11). Cooking ground beef to 155°F for 17 seconds is correct cooking, not contamination; spoilage by yeasts and molds is natural decay, not pathogen transfer; and seasoning or brining a dish is ordinary preparation. Each of the three wrong options describes a real kitchen event that simply is not a transfer of pathogens.
Foods are stored top to bottom in order of increasing required cooking temperature: ready-to-eat foods on top, then whole seafood and steaks (145°F), then ground meat (155°F), with raw poultry (165°F) on the bottom (FDA Food Code §3-302.11). Poultry goes on the bottom precisely because it is cooked hottest, so putting raw chicken on top inverts the rule and lets its juices drip onto food that will be cooked less or eaten raw. Covering and dating containers is required for other reasons but does not remove the risk of drips, spills, and leaking packaging. Grouping the raw meats on the top shelf still leaves raw juices above ready-to-eat food.
FDA Food Code §3-302.11Sesame became the ninth major food allergen in the United States under the FASTER Act, effective January 1, 2023, joining milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, and soybeans. The FASTER Act added sesame alone, so the option pairing mustard with it is false. FALCPA established the original eight allergens and was never expanded to include corn, and the FDA has never added garlic. Note the scope of the stem: it asks about the list recognized in the United States, so an allergen that must be declared only elsewhere (mustard is declarable in Canada and the EU) is still not part of the U.S. Big 9.
Staff must give a guest accurate allergen information, so a server who is unsure has to check with the kitchen or the manager and verify every ingredient, including sauces, oils, and marinades, before answering. Reassuring the guest that it is probably fine is a guess presented as fact. The appearance of a dish and the menu wording do not reveal peanut oil, peanut flour, or a shared fryer. Removing the visible peanuts leaves the peanut protein already in the food and any cross-contact from shared equipment, which is enough to trigger anaphylaxis.
Cross-contact is the unintentional transfer of an allergen protein into a food that should be free of it, for example frying breaded shrimp and then french fries in the same oil, or using the same unwashed tongs. Allergen proteins are not destroyed by heat, so cooking a dish to 165°F kills pathogens but leaves the allergen fully active. Freezing and thawing likewise does not remove or break down an allergen. Putting two ingredients together on purpose in a recipe is normal cooking and only becomes an allergen problem if the guest is not told what is in the dish.
Allergen proteins survive heat, so the only reliable control is to prevent contact entirely: wash hands, change gloves, use freshly cleaned and sanitized equipment, utensils, and surfaces, and where possible prepare the dish in a separate area. Rinsing, wiping, and drying the plate still leaves shellfish protein on the plate and in the food. A smaller portion still delivers the allergen, and a trace amount is enough to cause anaphylaxis in a sensitive guest. Cooking hotter destroys pathogens, not allergens, so a higher temperature does nothing for this guest.
An allergic reaction shows up as hives, itching, swelling of the face, lips, or throat, wheezing, and difficulty breathing, and it can progress to life-threatening anaphylaxis within minutes, so staff should call for emergency help immediately. A stomachache that first appears several hours later fits the pattern of a foodborne illness or a food intolerance, not a rapid allergic reaction: an intolerance is a digestive reaction, not an immune one, and it does not cause anaphylaxis. Improved appetite, energy, concentration, alertness, and hydration are the opposite of a reaction, and a craving for another portion is not a symptom of one either.
ALERT is the FDA food-defense tool: Assure (buy from safe, approved suppliers), Look (monitor the security of products and storage areas), Employees (know who is in the facility), Reports (keep security and receiving records), and Threat (know what to do and whom to contact if there is a threat). The other three expansions are invented. Alarm/Lockdown/Evacuate/Report/Testing describes a general emergency-response drill, not food defense; the analyze/list/evaluate and assess/label/enforce sets are generic management verbs with no food-defense meaning.
Deliberate contamination is intentional: someone tampers with, sabotages, or attacks the food supply to cause harm, which is why food-defense programs such as ALERT exist. A lapse in cooking or holding temperature is exactly the kind of handling mistake that defines accidental contamination, and natural spoilage past a use-by date is decay rather than contamination by a person. Security measures do work: limiting access to storage areas, buying from approved suppliers, and keeping receiving records all reduce the risk of a deliberate act.
The manager should take the complaint seriously, stop serving the affected batch of soup, keep the screw, and trace where it came from, most often a loose part on a mixer, slicer, or kettle, so the same failure cannot recur. Comping a dessert while the rest of the batch stays on the line leaves the next guest exposed to the same hazard. Blaming the supplier without inspecting the equipment skips the most likely source and fixes nothing. A metal screw is a genuine physical hazard that can cut the mouth or throat, so calling it harmless is both wrong and a liability.
Poisonous or toxic materials must be physically separated from food, equipment, utensils, linens, and single-service items, normally in a dedicated area located below or away from them, and held in the original labeled container or a working container marked with the common name (FDA Food Code §7-201.11). A prep sink is a food-contact area, so chemicals stored in it can contaminate food and produce being washed. Sharing the dry-storage shelf with the flour, the sugar, and the spices puts a chemical directly above or beside food. Unlabeled working containers near the cooking line invite a cook to grab the wrong bottle.
FDA Food Code §7-201.11Physical contaminants are hard or soft foreign objects that can injure a guest: metal staples, glass, bone fragments, hair, fingernails, bandages, and bits of packaging. A metal staple from a produce box is a classic example, which is why deliveries are inspected and boxes are opened away from open food. Sanitizer residue left on a cutting board is chemical contamination, Salmonella on the shell of an egg is biological contamination, and peanut oil left in a deep fryer is allergen cross-contact.
A food-contact surface used for raw poultry must be washed, rinsed, and sanitized before it touches ready-to-eat food, or the kitchen must use separate color-coded boards and utensils (FDA Food Code §3-302.11). Rinsing under warm running water and wiping with a dry towel both move pathogens around without removing or killing them; sanitizing is a separate step that rinsing cannot replace. Cutting the tomatoes first would have helped in this specific sequence, but the option keeps using the same unwashed board, so raw chicken residue is still left for whatever is prepped next.
A peanut-free claim only holds if the operation controls both hidden peanut ingredients (peanut oil, peanut flour, sauces and coatings that contain them) and cross-contact from shared fryers, mixers, utensils, prep surfaces, and gloves. A trace amount transferred from shared equipment is enough to cause a reaction, so checking whether peanut pieces are visible tells you nothing. Menu wording is a claim, not a control, and it is exactly what has to be earned. Reading supplier labels is one necessary step but stops at the ingredients and does nothing about what happens on the prep line.
Brewed soy sauce is made from both wheat and soybeans, two of the Big 9 allergens, and guests rarely expect the wheat, so it is a classic hidden source in marinades, dressings, stir-fries, and dipping sauces. Managers and servers must know the hidden allergens in every sauce on the menu. A rinsed and sliced apple, plain white rice steamed in water, and sealed bottled spring water contain none of the Big 9, which is why they are safe answers to give a guest.
Produce showing signs of pests, damage, or contamination is rejected at the receiving dock, set aside for the driver, and noted on the invoice, so it never enters the establishment. Washing contaminated produce does not remove pest droppings, urine, or the pathogens they carry. Freezing holds pathogens in place rather than killing them, and any crate that shared a truck with pest activity is suspect, so keeping the undamaged items without inspecting them is a gamble. Storing the bad product separately and using it first still serves contaminated food to a guest.
Preventing cross-contact means washing hands, putting on clean gloves, and using freshly cleaned and sanitized equipment, utensils, and surfaces dedicated to that one order, then running the plate straight to the guest. Frying in oil that held breaded shrimp carries shellfish and wheat protein into the food, and heat does not destroy it. Working on the busiest fry station in the middle of the rush surrounds the order with other allergen-containing foods and airborne flour. Keeping the same gloves transfers allergen protein straight from the previous ticket.
Almonds are tree nuts, along with walnuts, cashews, pecans, and pistachios. Peanuts ripen underground and are legumes, and they are their own separate Big 9 allergen; chickpeas grow on a low pod-bearing plant and sunflower seeds come from a flower head, and neither one is among the Big 9. Because peanuts and tree nuts are separate categories, both must be tracked individually.
An infected wound can carry Staphylococcus aureus, so it must be covered with a clean impermeable bandage and, on the hand, a single-use glove or finger cot; if the infection is significant, the handler may need to be restricted from working with food. Rinsing the cut does not stop it weeping, working uncovered behind tongs still leaves drainage on hands and equipment, and waiting for blood to seep through means the food is already exposed.
Storing or serving food in a container that held a toxic chemical, or letting cleaner residue reach food, is chemical contamination. A hair is a physical contaminant, raw beef juice dripping onto lettuce is biological cross-contamination, and serving a cream-thickened bisque to a milk-allergic guest is an allergen problem, not a chemical one. Using only food-grade containers and controlling chemicals prevents this hazard.
Anaphylaxis is a life-threatening emergency, so staff must call emergency services immediately, follow the operation's emergency plan, and assist the guest, who may need epinephrine. Water does not dilute an allergen once the reaction has started, waiting 15 minutes can let the airway close, and taking the guest outside for fresh air leaves nobody watching if they collapse — fresh air does not reverse anaphylaxis. Managers should train staff to recognize and respond to reactions.
Handling ready-to-eat food with gloves, tongs, or other utensils instead of bare hands reduces biological contamination from pathogens like Norovirus, Hepatitis A, Shigella, and Staph carried on hands. Note the word mainly in the stem: glass shards, sanitizer residue on utensils, and a shared fryer basket are real hazards, but none of them travels on a food handler's hands, so the bare-hand rule is not what controls them.
A core food-defense practice is limiting access to preparation and storage areas so only authorized employees enter, reducing opportunities for deliberate tampering. A propped delivery door and unescorted vendors both hand a stranger an unwatched route to open food, and chemicals shelved above prepped food invite a spill or a deliberate addition.
Regular flour tortillas are made from wheat flour and must be avoided for a wheat-allergic guest, while handmade corn tortillas, plain grilled chicken, and plain steamed white rice are wheat-free as long as no sauce or breading is added. Managers should teach staff which menu items and substitutions are safe. Reading labels and recipes helps catch hidden wheat in breading, sauces, and thickeners too.
Preventing physical contamination involves removing potential foreign objects: not wearing jewelry that can fall in, using shatter-resistant light shields, keeping fingernails trimmed, and inspecting food for bones, pits, or packaging. Leaving salads out at room temperature is a time-temperature failure, rinsing raw chicken sprays pathogens around the sink instead of removing them, and salt does nothing to a metal shaving or a glass shard — none of the three removes a foreign object.
Unlike most pathogens, allergen proteins are not destroyed by cooking or freezing, so the only reliable protection for an allergic guest is preventing the allergen from contacting the food at all. Rinsing a plate leaves protein behind on the food and the dish, freezing does not break the protein down, and heat above 165°F kills pathogens without changing the allergen — which is why none of those three can make a dish safe once cross-contact has occurred.
A strong ammonia smell and slimy or soft flesh indicate spoilage, so the fish should be rejected. The other three describe fresh fish and are reasons to accept the delivery: bright red gills, firm flesh that springs back, clear slightly bulging eyes, and only a mild sea smell. Accepting spoiled fish risks scombroid poisoning and other illness.
Milk allergens hide in ingredients such as butter, whey, casein, and many creamy sauces, so staff must read labels and recipes carefully. Black coffee brewed with water and served over ice, extra-virgin olive oil, and vinegar with salt and pepper carry no dairy protein. Knowing hidden dairy sources is essential to protect a milk-allergic guest.
Cold TCS food should be received at 41°F or below; deliveries arriving warmer than 41°F should be rejected because time-temperature abuse may have allowed pathogen growth. Accepting food at 50°F, 60°F, or 70°F would bring unsafe product into the operation. Checking delivery temperatures is a key receiving control.
A clear communication system, such as marked tickets, allergen flags, or verbal confirmation between servers and kitchen, ensures everyone knows an order must be allergen-safe. Keeping the detail at the host stand means the cook never learns of it, leaving it to each cook's judgment produces a different procedure on every station, and firing the order last flags nothing to anyone who touches the plate.