Lesson Notes Dairy Production Food Safety Lesson Plan Purpose: The purpose of this lesson is to expose students to the efforts made by dairy producers to ensure a safe and healthy product for consumption. Objectives: 1. The students will be able to describe how food safety begins with each and every cow on a dairy; 2. The students will be able to describe the steps of the milking process that effect food safety; 3. The students will explain the process that milk goes through following milking; 4. The student will be able to defend the sampling procedures used by the industry; 5. The student will be able to categorize each step of the cleaning and sanitation process in a parlor’s milking system; and 6. The student will be able to explain why record keeping and inspection is important to dairymen. Teks/Taks: TEKS - 119.27 Food Technology Identifying Dairy Products (9)(E) 119.13 Applied Agriculture Science and Technology 4 (C) 5 (A) TAKS - Food Science (English) 1(6)(E) 1(7)(F) 2(10)(B) Biology 3(4)(D) Math 9(8.3)(B) Focus: Tell students a story related to trying a new restaurant. You Power try a new restaurant that has been built close to your home. When you sit Point down you notice that a spoon on the table is dirty, no big deal, the waiter Slides brings you another. Later, the kitchen door swings open and you see a cook sneezing over a workspace, Yuck! Finally, your food arrives, to your surprise there is a hair in the middle of your entrée. – What would you do in this situation? How safe do you believe it would be to eat your entrée? Have you ever purchased a product at the grocery store that was of questionable quality? A dairy product? – Tie all of your students’ discussion to how safe our agricultural food supply is. Also, discuss what great lengths are taken in the dairy industry to deliver a safe and wholesome product. Lesson Content: Power I. Food Safety on a Dairy Begins with Each Individual Cow: Point A. A Clean Environment: Slides 1. Confined cattle are bedded on sand and have barn lanes flushed or vacuumed two times per day. This removes manure and keeps the cow clean, which is important during the milking process. 2. All milking equipment is constructed using stainless steel and replaceable rubber parts, which can all be sanitized. 3. Dairymen profit greatly from a clean environment, therefore, most modern dairies are clean and well kept. B. Animal Health: 1. If dairy cattle become sick they are immediately separated from the remainder of the herd and their milk is collected and destroyed. 2. Milk from sick cows never mixes with that of healthy cows. 3. Dairy workers are constantly looking for signs of illness and a veterinarian visits every cow on a dairy monthly. 4. Milk collected from healthy cows is also subjected to testing that will find any indicators of disease or residual from medical treatment. II. Food Safety and the Milking Process: Reference A. Entering the Milking Parlor: the Modern 1. As cows enter the milking parlor they are typically misted Dairy Tour with water in order to cool and help clean them. Workers can Video. manually apply larger amounts of water if needed. 2. As the cow is situated to be milked in the parlor her udder is gently sprayed with water by a worker. This removes any large debris. 3. During the milking process a waste collection system removes any manure or urine that may be excreted. This keeps the milking area very clean. B. The Milking Process: 1. Before milking each cow’s udder is thoroughly cleansed in the following manner: a) Each teat is dipped into iodine or other germ killing solution. b) A dairy worker will draw a small amount of milk from each teat in order to prime the udder and remove any contamination. This is called the forestrip. c) After the forestrip, another worker will dry each teat with a clean and soft rag. d) Finally, the milking mechanism is applied to the cow’s udder. e) After milking, the cows’ teats are once again dipped to prevent infection and to keep the skin on each teat soft and prevent chapping. f) All workers in the milking parlor wear rubber gloves in order to promote a healthy environment. 2. All milking equipment in the parlor is regularly inspected, cleaned, maintained and replaced as needed. One example is the vacuum boot liners that attach to each teat on the milking units. C. Food Safety for Milk Following the Milking Process: 1. Following the milking process the milk that is collected is piped through a filtration process that removes debris and solids. 2. Immediately following filtration, the milk is transferred to a small holding tank. This tank controls the volume of milk, which enters the cooling system. a) If too much milk is passed through the cooling system at once, a food safety issue will arise because the large volume of milk will not be dropped to the appropriate temperature. 3. Following the filtration process the milk’s temperature is adjusted. a) As the milk leaves the cow its temperature is 101º F b) The milk is passed through a special cooling unit, which uses chilled water as a cooling agent. The cooling unit first steps the milk’s temperature down to 75º F and then to 35º F. (1) If at any point in time the milk temperature reaches 37º F or greater, the entire dairy shuts down. 4. After the milk is chilled it is sent to large storage tanks, which hold the milk before it is collected into a tanker truck. a) Each storage tank has agitation systems to keep the milk from separating into parts. b) The tanks also have self-cleaning systems. 5. Bulk milk is collected into tanker trucks daily. a) Before the milk is loaded onto a truck it is sampled by the driver. The driver takes several samples for different organizations: (1) One sample for the producer (2) 3-4 samples for the buyers of the milk (3) One sample for the state health department Reference (4) One sample for the producer’s coop the Dairy- b) Each dairy operation in a coop has their loads averaged Related Agencies and compared against the average of the coop. This helps lesson to ensure consistency and quality of product. c) As milk is loaded into a tanker it is filtered once more in order to collect any debris that may have been missed during the initial filtration process. D. Cleaning of the Milking System. Power 1. Depending on the size of the dairy and milking schedules, all Point milking equipment and associated systems are cleaned and sanitized two to three times per day. 2. The bulk milk storage tanks are cleaned after every pick-up by a tanker truck. 3. Flushing the overall milking system. The following process happens during every cleaning cycle anywhere milk flows or comes into contact with: a) All lines are first flushed with a warm water rinse - 90ºF. (1) If the water is too cool, milk residue will coagulate. If too hot the milk residue will cook to the inside of the stainless steel pipes. b) Hot wash - 140º F water with a caustic soap that contains lye. c) Warm water rinse - 90º F d) Cold acid rinse with an iodine additive. (1) This final step prevents any bacterial growth, but is safe for the milk. Record Keeping and Inspections Related to Food Safety. Visit web E. Inspections: links in Power 1. Dairies can be inspected by two different food safety Point organizations in most states and can be voluntarily inspected by more if the dairy producer so wishes. a) Your State Department of Health inspects dairies regularly, just as a restaurant is inspected. The health department also receives weekly milk samples from every dairy in the state. b) Federal inspectors from the Food and Drug Administration (FDA) visit dairies twice a year if the dairy ships milk across state lines. F. Record Keeping: 1. Dairymen keep numerous records dealing with finances, environmental impact, production, and food safety. Efficient and profitable dairies demand that up-to-date records be accurate and maintained regularly. 2. For example, temperature readings on milk are recorded 24 hours, 7 days a week. Many dairymen utilize computers to keep detailed records for each cow, in some cases one cow may have an entire database dedicated to it alone. Records on production and milk sales also affect food safety on a dairy. III. Review: Verbal 1. Where does food safety start on a dairy? Review 2. Name one process that occurs in the milking parlor that promotes food safety? 3. Why is milk sampled, and how many samples are typically taken? 4. What temperature is milk stored at in bulk storage tanks? At what milk temperature does a dairy stop operating? 5. Describe the cleaning process for milking equipment? Set-up Guided Practice: prior to Set-up a tour of your school’s cafeteria and kitchen. Have the students in your lesson class team–up and develop a checklist. The students should draw parallels between the cafeteria’s kitchen and a dairy where food safety is concerned. Have students consider construction materials, food handling practices, organization, inspections, cleaning schedules, etc. *Alternate Guided Practice – Have students view the video on this CD that discusses food safety in dairy operations. Independent Practice: Refrigeration Experiment (See Record Sheet Following Lesson Plan) – Give each student a plastic cup and instruct him or her to fill half of it with milk (Make sure that the milk has just been taken from the refrigerator). Instruct students to take temperature measurements of the milk as directed on the record sheet. After taking temperature measurements and answering the questions on the record sheet have your students cover the top of their cup with plastic wrap. Let the cups set as directed by the record sheet. Have students answer all questions on the record sheet. List of Materials: 1. Lesson & Power Point 2. Cafeteria Tour Set-Up 3. Internet 4. Cold Milk 5. Plastic Cups 6. Plastic Wrap 7. Thermometers 8. Watch or clock with second hand 9. Record Sheets for Each Student (Below) References: Dairymen Interviews Name: Food Safety Milk Experiment Record Sheet Procedure: 1. Fill a plastic cup half full of milk directly from the refrigerator. (Milk must be approx. 33º F) 2. Record temperatures as instructed in the table below. 3. Cover cup of milk with plastic wrap and let set for 24 hours, answer questions below. Let milk set for another 24 hours, answer questions below. Part I: Milk Temperature Current Room Temperature Temperature of Refrigerated Milk Temperature of Milk Immediately After Poured Into Cup Milk Temperature after 2 minutes Milk Temperature after 4 minutes Milk Temperature after 6 minutes Milk Temperature after 10 minutes Questions: 1. Theoretically, how long would it take to stop operations at a modern dairy if the shutdown temperature was 37º F? 2. If a dairyman’s 1000-gallon bulk tank temperature rose above 37º F, how much money did the dairyman lose if raw milk is bringing $17.62 per hundred weight and one gallon of milk weighs 8.59 pounds? Part II: Milk Parishibility & Residue Questions & Observations: 1. Describe the consistency and smell of the milk after 24 hours at room temperature. 2. Describe the consistency and smell of the milk after 48 hours at room temperature. 3. What is happening in the milk as refrigeration is removed? 4. Dispose of the milk into a sink; note the sides of the cup. Try to rinse the cup with cool water, how does the milk residue react? How do dairymen combat this?