Presentation on theme: "The Flow of Food: an Introduction"— Presentation transcript:
1 The Flow of Food: an Introduction Chapter Number 5The Flow of Food: an IntroductionClass NameInstructor NameDate, SemesterBook TitleBook Author
2 Learning Objectives After this presentation, you should be able to complete the following Learning Outcomes5.05.1Ways of preventing cross-contamination5.2Ways of preventing time-temperature abuseDifferent types of temperature-measuring devices and their uses5.3At the end of this lecture each student should have a general understanding of the chapter contents and a firm ability to accomplish the learning outcomes on this slide.How to calibrate and maintain different temperature-measuring devices5.45.5General guidelines for thermometer use
3 5.0 KEY TERMS • Flow of food: Path food takes through an operation, frompurchasing and receiving throughstoring, preparing, cooking, holding,cooling, reheating, and serving.• Bimetallic stemmed thermometer:The most common and versatiletype of thermometer, measuringtemperature through a metal probewith a sensor in the end. Most canmeasure temperatures from 0°to 220°F (–18° to 104°C) and areaccurate to within ±2°F or ±1°C.They are easily calibrated.• Thermocouples: Thermometers thatcheck food temperature through asensor on the tip of a metal probe.• Thermistors: Thermometers thatcheck food temperature through asensor on the tip of a metal probe.• Time-temperature indicator (TTI):Time and temperature monitoringdevice attached to a food shipmentto determine if the product’stemperature has exceededsafe limits during shipment orsubsequent storage.• Calibration: Process of ensuringthat a thermometer gives accuratereadings by adjusting it to a knownstandard, such as the freezing pointor boiling point of water.
4 • Ice-point method: Method of Boiling-point method: Method of 5.0KEY TERMS• Ice-point method: Method ofcalibrating thermometers based onthe freezing point of water.Boiling-point method: Method ofcalibrating a thermometer based onthe boiling point of water.
5 Ways of Preventing Cross-Contamination 5.1Ways of Preventing Cross-ContaminationCROSS-CONTAMINATIONMany things can happen to food as it moves from purchasing and receiving through storing, prepping, cooking, holding, cooling, reheating, and serving.This path is known as the flow of food.
6 Ways of Preventing Cross-Contamination 5.1Ways of Preventing Cross-ContaminationCROSS-CONTAMINATIONCross-contamination is a major hazard in the flow of food.Pathogens can be spread from food or unwashed hands to prep tables, utensils, equipment, or other food.Cross-contamination can occur at almost any point within the flow of food.When you know how and where it can happen, it is fairly easy to prevent.
7 Ways of Preventing Cross-Contamination 5.1Ways of Preventing Cross-ContaminationGUIDELINES FOR PREVENTING CROSS-CONTAMINATIONUsing separate equipmentUse separate equipment when preparing each type of food.Colored cutting boards and utensil handles can help you keep equipment separate.Cleaning and sanitizingClean and sanitize all work surfaces, equipment, and utensils after each task.Pathogens, such as Salmonella spp., can contaminate food through cross-contamination.
8 Ways of Preventing Cross-Contamination 5.1Ways of Preventing Cross-ContaminationGUIDELINES FOR PREVENTING CROSS-CONTAMINATION (cont.)Prepping food at different timesWhen using the same table to prep different types of food, prep raw meat, fish, and poultry at different times from ready-to-eat food so that the chance for cross-contamination can be minimized.Buying prepared foodBuy food items that do not require much prepping or handling.
9 Ways of Preventing Time-Temperature Abuse 5.2Ways of Preventing Time-Temperature AbuseTIME-TEMPERATURE CONTROLTime-temperature abuse is another major hazard in the flow of food.TCS food has been time-temperature abused any time it remains between 41° and 135°F (5° and 57°C).This is called the temperature danger zone because pathogens grow in this range. They grow especially fast between 70°F and 125°F (21° and 52°C).
10 Ways of Preventing Time-Temperature Abuse 5.2Ways of Preventing Time-Temperature AbuseTIME-TEMPERATURE CONTROLTCS food is being time-temperature abused whenever it is handled in the following ways:Cooked to the wrong minimum internal temperatureHeld at the wrong temperatureCooled or reheated incorrectly Time also plays a critical role. The longer food stays in the temperature danger zone, the more time pathogens have to grow.To keep food safe, you must reduce the time food spends in this temperature range.TCS food must be thrown out if it stays in the temperature danger zone for four hours or more.
11 Ways of Preventing Time-Temperature Abuse 5.2Ways of Preventing Time-Temperature AbuseAVOIDING TIME-TEMPERATURE ABUSEFood handlers should avoid time-temperature abuse by following good policies and procedures.The ones you establish should cover the following areas:MonitoringLearn which food items should be checked, how often, and by whom.Assign duties to food handlers in each area.Make sure they understand what to do, how to do it, and why it is important.
12 Ways of Preventing Time-Temperature Abuse 5.2Ways of Preventing Time-Temperature AbuseAVOIDING TIME-TEMPERATURE ABUSEToolsMake sure the correct kinds of thermometers are available.Give food handlers their own thermometers.Have them use timers in prep areas to check how long food is in the temperature danger zone.RecordingHave food handlers record temperatures regularly.Make sure they write down when the temperatures were taken.Provide sample forms for recording this information next to cooking and holding equipment.
13 Ways of Preventing Time-Temperature Abuse 5.2Ways of Preventing Time-Temperature AbuseAVOIDING TIME-TEMPERATURE ABUSE (cont.)Time and temperature controlHave procedures that limit the time food spends in the temperature danger zone.Corrective actionsMake sure food handlers know what to do when time and temperature standards are not met.
14 Different types of temperature-measuring devices and their uses 5.3Different types of temperature-measuring devices and their usesCHOOSING THE CORRECT THERMOMETERThe most important tool you have is the thermometer. There are many types of thermometers. Three types are commonly used in operations:Bimetallic stemmed thermometersThermocouplesThermistors
15 Different types of temperature-measuring devices and their uses 5.3Different types of temperature-measuring devices and their usesBIMETALLIC STEMMED THERMOMETERSChecks temperatures from 0° to 220°F (–18° to 104°C)Use it to check food temperatures both during receiving and in a hot- or cold-holding unit.When checking temperatures, insert the stem into the food up to the dimple for proper reading.Useful for checking the temperature of large or thick food.Not practical for thin food, such as hamburger patties.If you buy bimetallic stemmed thermometers for your operation, make sure they have the following features.Calibration nutEasy-to-read markingsDimple
16 Different types of temperature-measuring devices and their uses 5.3Different types of temperature-measuring devices and their usesTHERMOCOUPLES AND THERMISTORSThermocouples/ thermistorsCheck temperatures through a metal probe and display digitallySensing area on the tip of their probe.Not necessary to insert them into the food as far as bimetallic stemmed thermometersGood for checking the temperature of both thick and thin food
17 Different types of temperature-measuring devices and their uses 5.3Different types of temperature-measuring devices and their usesINFRARED THERMOMETERSInfrared (Laser) ThermometersMeasures the temperatures of food and equipment surfacesQuick and easy to use as they do not need to touch a surface to check its temperatureLess chance for cross-contamination and damage to foodCannot measure air temperature or the internal temperature of foodFollow these guidelines for using infrared thermometers.DistanceHold the thermometer as close to the food or equipment as you can without touching it.BarriersRemove anything between the thermometer and the food, food package, or equipment.Avoid taking readings through metal, such as stainless steel or aluminum.Do not take readings through glass.Manufacturer’s directionsAlways follow the manufacturer’s guidelines for most accurate readings.
18 Different types of temperature-measuring devices and their uses 5.3Different types of temperature-measuring devices and their usesTIME-TEMPERATURE INDICATOR (TTI)Time-temperature indicatorAttached to packaging by the supplierA color change appears in the TTI window if the food has been time-temperature abused during shipment or storage.This color change is not reversible, so you know if the item has been abused.Some suppliers place temperature-recording devices inside their delivery trucks.
19 Calibrate and maintain different temperature-measuring devices 5.4Calibrate and maintain different temperature-measuring devicesHOW TO CALIBRATE THERMOMETERSThermometers can lose their accuracy when they are bumped, dropped, or experience severe temperature change.There are two ways to calibrate a thermometer:ice-point methodboiling-point method
20 Calibrate and maintain different temperature-measuring devices 5.4Calibrate and maintain different temperature-measuring devicesHOW TO CALIBRATE THERMOMETERSBoiling-Point MethodTo calibrate a thermometer using the boiling-point method, follow these steps:Bring clean tap water to a boil in a deep pan.Put the thermometer stem or probe into the boiling water. Make sure the sensing area is submerged. Wait 30 seconds or until the indicator stops moving. Do not let the stem or probe touch the container.Adjust the thermometer so it reads 212°F (100°C). This temperature will vary depending on the boiling point for your elevation. Water’s boiling point is about 1°F (about 0.5°C) lower for every 550 feet (168 meters) above sea level.
21 Calibrate and maintain different temperature-measuring devices 5.4Calibrate and maintain different temperature-measuring devicesHOW TO CALIBRATE THERMOMETERSIce-Point MethodThermometers are often calibrated using the ice-point method. Follow these steps to use this method.
22 General guidelines for thermometer use 5.5General guidelines for thermometer useGENERAL THERMOMETER GUIDELINESCleaning and sanitizingThermometers must be washed, rinsed, sanitized and air-dried before and after use.Keep storage cases clean as well.CalibrationCalibrate thermometers before each shift and before the first delivery arrives.AccuracyFood thermometers need to be accurate to +/- 2°F or +/- 1°C.Air temperature/food storage equipment need to be accurate to +/- 3°F or +/- 1.5°C.
23 General guidelines for thermometer use 5.5General guidelines for thermometer useGENERAL THERMOMETER GUIDELINES (cont.)Glass thermometersGlass thermometers, such as candy thermometers, can be a physical contaminant if they break.They can only be used when enclosed in a shatterproof casing.Checking temperaturesWhen checking the temperature of food, insert the thermometer stem or probe into the thickest part of the food.Take another reading in a different spot. The temperature may vary in different areas.When using a bimetallic stemmed thermometer, insert the stem all the way into the food from the tip to the end of the sensing area.When checking the internal temperature of thin food, such as meat or fish patties, use a small diameter probe.Before recording a temperature, wait for the thermometer reading to steady.