The Dairy Industry: Process, Monitoring, Standards, and Quality
Farmers and processors work hard to make sure your milk is safe
Sampling and analysis occur along the milk processing train: from the collection at the farm level, to intake at the dairy plant, the processing steps, and the end products. Milk has a short shelf life; however, products such as milk powders have allowed a global industry to be developed. Quality control tests are vital to support activities for hygiene and food standards to meet regulatory and customer demands. Multiples of chemical and microbiological contamination tests are undertaken. Hazard analysis testing strategies are necessary, but some tests may be redundant; it is, therefore, vital to identify product optimization quality control strategies. The time taken to undergo testing and turnaround time is rarely measured. The dairy industry is a traditional industry with a low-margin commodity. Industry 4.0 vision for dairy manufacturing is to introduce the aspects of operational excellence and implementation of information and communications technologies. The dairy industries’ reply to Industry 4.0 is represented predominantly by proactive maintenance and optimization of production and logistical chains, such as robotic milking machines and processing and packaging line automation reinforced by sensors for rapid chemical and microbial analysis with improved and real-time data management. This chapter reviews the processing trains with suggestions for improved optimization.
Dairy farmers strive every day to produce wholesome milk and milk products that your family can feel good about eating. The U.S. Department of Agriculture (USDA) and Food and Drug Administration (FDA) regulate U.S. milk production, and its guidelines are some of the strictest in the industrialized world. Farmers, processors and government agencies all work together to ensure the milk you drink is safe and of the highest quality.
Organic Milk vs. Regular Milk
A common misconception is that organic milk is healthier than regular milk. In reality, there are no nutritional or health differences between organic and traditional milk.
In regards to milk safety, there is no difference between organic and conventional milk production. All milk commercially produced in the U.S. adheres to the same strict federal standards for quality, purity and sanitation. All milk—both regular and organic—is tested for antibiotics, both on the farm and at the processing plant. In accordance with government regulations, any milk testing positive for antibiotics cannot be sold to the public.
Dairy farms selling milk using the “USDA organic” seal must adhere to the following criteria:
- Cows are exclusively given feed grown without the use of pesticides or commercial fertilizers.
- Cows are given periodic access to pasture.
- Cows are not treated with supplemental hormones.
- Cows have not been given certain medications to treat illness.
There is no scientific evidence concluding that organic dairy products are safer or healthier than conventional dairy products. Strict government standards ensure both conventional and organic milk are wholesome, safe and nutritious. The USDA conducts an extremely thorough Pesticide Data Program, which concludes that all residue detections within milk and cream are “much lower than established tolerances.”
Pasteurization and Raw Milk
Pasteurization is a process that kills harmful bacteria by heating milk to a specific temperature for a set period of time. The process of pasteurization typically involves heating raw milk to 161.5˚F for 15 seconds and then immediately cooling it.
“Ultra-pasteurization” is a process that heats milk at a higher temperature for a longer period of time in order to extend a product’s shelf life. It is utilized to create shelf-stable milk products.
Some people continue to believe that pasteurization harms milk and that raw milk is a safe and healthier alternative. According to the Food and Drug Administration, raw milk can harbor dangerous microorganisms, such as salmonella, E. coli and listeria, which can pose serious health risks to you and your family. Outbreaks of tuberculosis have been traced back to the consumption of raw milk.
Here are some proven facts about raw milk and pasteurization:
- Raw milk DOES NOT kill dangerous pathogens by itself.
- Pasteurizing milk DOES NOT cause lactose intolerance and allergic reactions.
- Pasteurization DOES NOT affect the taste of milk.
- Pasteurization DOES NOT make it safe to leave milk unrefrigerated for an extended period of time, particularly after it has been opened.
- Pasteurization DOES kill harmful bacteria.
- Pasteurization DOES save lives.
Pasteurization has been recognized around the world as an essential tool to ensure milk safety without an impact on overall nutrition. This protocol has been in effect for more than a century and is regulated by the USDA.
Getting the milk onto shelves
Last year, Land O’Lakes partnered with innovative startup Plus.ai to deliver 40,000 pounds of butter 2,800 miles. Did we mention that the truck drove itself? It was the first coast-to-coast commercial freight trip made by a self-driving truck, traveling from Tulare, California, to Quakertown, Pennsylvania, in less than three days. The driving system offered the tech to do it safely, including cutting-edge sensors, deep learning algorithms and simultaneous location and mapping (SLAM) technologies.
While that is an exciting twist on transportation, it’s the everyday, over-the-road truckers whose praises we’re singing this month.
Drivers are an integral part of the process, arriving on farm to collect the milk, delivering it for processing and then transporting the finished products to stores and customers across the country.
Homogenization is a process that gives milk its rich, white color and smooth texture. Milk that has not been homogenized contains a layer of cream that rises to the top of its container. Before the homogenization process was used, milk was shaken or mixed to achieve consistency. The homogenization process involves reducing the size of the fat globules into minuscule portions that are dispersed evenly throughout the milk. Homogenization usually is achieved by pumping milk through small filters under very high pressure.
During milk processing, all post-milking handling must maintain the milk’s nutritional value and prevent deterioration caused by numerous physical and biological factors. In addition, equipment on the farm must be maintained to government and industry standards to uphold milk safety.
Here’s a quick run-through of the process of milk processing:
- Within 72 hours of receipt, the milk is pasteurized to kill all pathogenic bacteria that may be present (some bacteria do not cause spoilage, but are actually added to milk or cream after pasteurization to make “cultured” products such as cheese, cottage cheese, yogurt, buttermilk, acidophilus milk and sour cream).
- A large centrifuge called a separator spins the milk at 2,000 rotations per minute, separating the cream and skim portions of the milk. Blending the components in various proportions creates different milk products. Excess cream is used to make ice cream and butter.
- A homogenizer forces the milk under high pressure through a valve that breaks up the butterfat globules to such a size that they will not “coalesce,” or stick together (homogenization does not affect the nutrition or quality of the product; it is done entirely for aesthetic purposes and to prevent cream from rising to the top of milk).
- Liquid vitamins are added to fortify the milk, as vitamin quantities can be reduced by the heating process and the removal of butterfat (many states have standards that require the addition of milk solids, such as calcium, iron and protein).
Additional quality control tests are conducted before the milk is flavored (in the cases of chocolate, strawberry and other flavored milks), bottled and shipped to grocery stores in refrigerated trailers. It takes about two days for the milk to get from the cow to the store, and it’s tested multiple times so it’s fresh and safe. Once at the store, the dairy milk is immediately placed into a cold storage room or refrigerated display case, ready to be enjoyed by you and your family.