What's New in Cheese Technology?
A roundup of the latest in cheesemaking technologies shows that research sponsored by Dairy Management Inc.™ (DMI) and funded by America's dairy farmers is focused on finding new ways to manufacture cheese and enhance its quality. Studies are examining how to measure and develop cheese for specific melt, flow, stretch and fat content while maximizing great cheese flavor and more. All of these innovations are designed to satisfy the demands of consumers and the food industry for cheese "my way."
"Over the last 50 years, researchers have developed a fundamental understanding of the main factors controlling cheese quality," says Lloyd Metzger, dir. of the Minnesota/South Dakota Dairy Research Center and assistant professor in the School of Food Science and Nutrition at the University of Minnesota, Minneapolis/St. Paul. "Now it's possible to produce cheese with almost any flavor or texture profile."
David Barbano, professor of food science at Cornell University and director of the Northeast Dairy Foods Research Center, Ithaca, N.Y., indicates that he likes "the challenge of developing new approaches in processing technology to enable production of cheese and dairy products that meet the changing needs of the foodservice industry and consumers."
Here are some of the exciting efforts under way to satisfy America's growing appetite for cheese.
New cheeses, same equipmentTo produce all the cheese America wants, cheesemakers employ vast machines using 40,000 lbs of milk per batch. Working on that scale, however, may discourage cheese manufacturers from trying new techniques or recipes, since every test could mean throwing out tons of milk.
A new program at the University of Minnesota makes it possible to explore new techniques with relatively little waste. Scherping Systems, Winsted, Minn., has collaborated with Metzger to build a miniature, meticulously detailed copy of one of its machines. This pilot system, which also is now available at the dairy research centers at California Polytechnic State University in San Luis Obispo, and Utah State University in Logan, produces highly accurate test results on a small scale that translates well to commercial applications.
Metzger and his team of researchers are exploring how manufacturers can use such systems to expand into cheese varieties such as cottage cheese, Parmesan and blue cheese. So far, with support from DMI, the group has prototyped a process for making cottage cheese in a closed vat arrangement. The process has now been commercialized by a major cheese manufacturer, and turns out a superior cottage cheese product to boot. Programs are in development for "translating" the open-vat processes for certain cheeses into closed-vat protocols. By expanding the versatility and quality controls of cheesemakers, this development is helping create greater varieties of fresh, consistent, high-quality product.
Vatless mozzarellaTraditional vat-based cheese-making turns 10 lbs of milk into 1 lb of cheese and 9 lbs of whey. Now, Cornell researcher Syed Rizvi has invented a "vatless" method of continuous cheese production that captures soluble milk proteins upfront without producing whey. The result is zero whey Mozzarella-style cheese that yields valuable dairy proteins.
Rizvi's breakthrough application uses membrane microfilters to strain out the soluble milk proteins prior to cheesemaking. The concentrated casein retentate, or cheesemilk, is mixed with rennet and starter culture. In a coagulator, it becomes solid curd that is cooked, salted and stretched. Meanwhile, the filtered soluble milk proteins can be harvested for use in higher-protein, lower-carbohydrate foods and nutraceuticals to provide tremendous nutritional benefits to consumers.
One advantage of the vatless process is its flexibility, says Rizvi. By adjusting the microfilters, the cheesemilk or soluble milk proteins can be tweaked to yield exactly the desired chemistry. This flexibility helps Rizvi see potential applications of the process in making cottage cheese, processed cheese and cream cheese.
Moisture migration in 640sKeeping product quality consistent was critical when dairy processors first began manufacturing Cheddar in 640 lb blocks. Achieving that consistency was a challenge. Even in a very cold room, these giant blocks took 10 days to cool. And because cheese is an excellent insulator, the inside of the block tended to stay warm while the outer inches chilled. This temperature variation sometimes set up moisture migration that pulled liquid from the heart of the block into the outer portion. So, while the center might become drier than desired, the outer portion could sometimes become too soft, especially in reduced-fat cheese, rendering portions of the product unsatisfactory.
The answer to this challenge recently came from Cornell's Barbano. Barbano's solution involves changing the chemistry of cheesemilk as production begins. By adding carbon dioxide to reduced-fat milk and changing its pH, Barbano has been able to reduce the moisture migration rate from 6% to 1% or less and ensure a consistently appetizing texture throughout any 640 lb block.
"We still don't fully understand why this works so well," says Barbano, but he isn't letting that slow him down. Having found a solution for low-fat Cheddar, Barbano is now tackling the same challenge for full-fat cheese. By cracking the moisture migration puzzle, researchers are helping cheesemakers produce more Cheddar, more consistently, to give America's Cheddar-lovers the product they want.
Processed cheese insightsWhile processed cheese popularity is growing, it will likely grow even faster if dairy processors can more easily customize and control its characteristics. Processed cheese can be unpredictable, often making large-scale manufacturing a matter of educated guesswork.
To eliminate some of this variation, researchers in the DMI-supported dairy research centers and other universities are looking at each step and ingredient in making processed cheese. For example, researchers are learning what happens to functionality when they adjust the degree of proteolysis and levels of filtration in raw milk. Others are examining the impact of different ratios of casein fractions on texture and melt characteristics. Since various blends of emulsifying salts enhance or minimize certain cheese qualities, researchers are studying this phenomenon, too.
There are also research efforts into the effects of higher or lower processing temperatures on cheese firmness, elasticity, spreadability and flow. Finally, other researchers are developing new techniques and instruments for assessing qualities such as texture and melting. The reliable and reproducible data gained from these tools will provide information for creating very specific processed cheeses and cheese products.
A new breakthrough technique for testing and analyzing different processed cheeses helps manufacturers create new formulations. The technique uses a toaster-oven-sized machine already familiar to food manufacturers called the Rapid Visco Analyzer (RVA). The RVA can produce tiny lots of processed cheese that mimic the flow and melt characteristics of commercially produced batches.
Testing cheese formulations in the RVA takes the guesswork out of making processed cheese, says Metzger, who developed the technique. With the RVA, "I can quickly evaluate unique formulations or test new ingredients and find out which add value," he says.
Food technologists have used the RVA for years to test the viscosity of items such baby food. Metzger's breakthrough was recognizing that the RVA accurately simulates the heat and stirring action of large-scale cheesemaking equipment.
Technique removes fat not flavorIn the past, removing fat from aged Cheddar cheese also meant removing much of the flavor. Lately, though, Barbano and other researchers have discovered that most of the taste of Cheddar resides in the water phase, not the fat. So they've come up with a mechanical process for creating low-fat aged Cheddar by extracting Cheddar's oils after the complex cheese taste has developed fully. The resulting low-fat cheese is softer and creamier than conventional aged Cheddar, making it perfect as a table cheese. And, in the flavor realm, it's just as tasty as the original.
The process relies on centrifugal force and temperature to extract the oil. Cheesemakers can adjust the level of fat removed by adjusting the temperature. The resulting oil (about 17 lbs from 100 lbs of Cheddar) is almost tasteless and odorless and can be used as an ingredient in food systems. Since the process works on aged cheese, cheesemakers need make only one kind of Cheddar-full fat-and then convert to low fat just the amount needed to satisfy demand. Another plus is that the technique is expected to work with other full-flavored cheeses.
Accelerating Parmesan ripeningTo fully develop its nutty and fruity flavor, Parmesan cheese must age 10 long months, right?
Not necessarily, says Mark Johnson, a researcher at the Center for Dairy Research at the University of Wisconsin in Madison. Parmesan owes its taste to a complex cocktail of volatile fatty acids, ethyl esters and other compounds. A research team led by Johnson thinks that they may be able to imitate and improve upon this intricate blend through the activity of certain bacteria. They are working to identify and cultivate just the right strains in hopes of intensifying the Parmesan flavor.
The exact flavor chemistry of aged Parmesan is undefined. However, researchers have identified certain adjunct lactic acid bacteria that produce "flavor notes" much like that found in high-quality aged Parmesan. Research is focusing on learning if these bacteria can help produce an intense Parmesan flavor.
To find out, researchers are aging selected cheeses using these bacteria. After a specified period, they will analyze
the cheese for certain chemical compounds associated with
authentic Parmesan taste. The data gained will help in designing further tests to find exactly the starters, bacteria and cheese manufacturing methods to produce the high-quality Parmesan flavor they seek.
Take advantage of technologyThese innovations will help satisfy America's love for cheese-and build the cheese industry-by leading to more consistent, high-quality products.
You can leverage these new technologies with DMI as your partner. DMI provides a comprehensive technical support system with six dairy research centers, two applications labs and 100-plus experts in research and technology, nutrition and marketing. Just contact the DMI Technical Support Hotline at 800/248-8829.