Virginia Polytechnic Institute and State University

Susan Duncan, Dairy and Sensory Evaluation

Bill Eigel,                Food Biochemistry

Joe Marcy:               Food Processing

Merle Pierson: Food Microbiology

 Sean O’Keefe: Food Chemistry

Susan Sumner:   Food Safety

Walter Hartman:    Dairy Plant Manager whartman@vt.edu

Kim Waterman:  Dairy Chemistry    Kwater@vt.edu

Brian Yaun: Microbiology byaun@vt.edu           Phone: (540) 231-8697

 fst RESEARCH HIGHLIGHTS

 Effects of Starch-based Anti-caking Agents on the Browning of Shredded Mozzarella Cheese

     The Mozzarella cheese market has increased rapidly over the last decade due to the rising popularity of pizza and other Italian foods.  Controlling the of degree browning on Mozzarella cheese during the baking process and understanding the principles that influence browning is important to the cheese industry.                             

       One factor that can influence the browning of Mozzarella cheese is the addition of starch and cellulose-based anti-caking agents to the shredded cheese to prevent clumping.  Six anti-caking agents were applied to low moisture part skim Mozzarella cheese.  Both browning and physical properties of the baked cheese samples were examined.  Browning was monitored using a Minolta colorimeter, digital image technology, and spectrophotometric methods.  Physical differences measured were moisture loss during baking, water activity, and surface temperature.  Color measurements indicated that the starch-based anti-caking agents produced a baked cheese with a greater degree of browning than the samples treated with cellulose based anti-caking agents or no treatment (control).  The cellulose-based treatments and the control also had a significantly greater moisture loss than the potato starch-based treatments.  A negative correlation between percent moisture loss and the amount of browning was found (R²=0.51).   The average surface temperature was at least 16°C higher for the treatments containing potato starch than for the cellulose-based treatments.  A significant relationship between average surface temperature and browning was also found (R²=0.67).  These relationships suggest that the starch-based treatments impeded moisture loss, which decreased the amount of evaporative cooling.  An increase in surface temperature resulted from the decrease in the amount of evaporative cooling and thus the Maillard reaction was accelerated leading to increased browning. 

     The effects of the starch source were examined using starches from corn, rice and wheat.  These starches were compared to commercially available potato starch and cellulose anti-caking agents.  All starch sources were found to produce a greater degree of browning on the cheese sample compared to the cellulose treatment and control.

Four adjuncts treatments, including dimethypolysiloxane, lactic acid, partially hydrogenated sunflower oil, and a combination of the dimethylpolysiloxane and sunflower oil were added to cheese treated with potato starch to determine if a reduction in the degree of browning could be achieved.  No differences in browning between the potato starch treatment and those with added adjuncts were found. 

HOT TOPICS AND DAIRY ISSUES

 New Proposed Standards Will Improve Ice Cream Products and Boost U.S. Dairy Ingredient Sales

Washington, D.C. —  The International Ice Cream Association (IICA), a constituent organization of the International Dairy Foods Association (IDFA), petitioned the Food and Drug Administration (FDA) today to modernize and improve federal standards governing the manufacture of ice cream and other frozen desserts. IICA is seeking the improvements because new technologies and vastly increased ice cream product variety have occurred in the marketplace in the past 25 years, but the FDA standards have changed little in that time. "These changes will allow us to manufacture a greater variety of high-quality frozen desserts," said IICA Chairman Gary Wells, CEO of Wells' Dairy, Le Mars, Iowa. "That means more and better choices for our customers and consumers."

"Improvements in whey fractionation alone have evolved tremendously since the 1970s, yet we are still working with restrictions on the kinds of dairy proteins we can use," said Bill Oldenburg, vice president of operations, Dreyer's Grand Ice Cream, Oakland, Calif.

"With dozens and dozens of new flavors on the market and the need to meet new consumer demands, we need more flexibility in the milk proteins we can use. Whey protein — a constituent of milk — is especially attractive to use because it has superior whipping and freezing properties, meaning we can produce a more satisfying ice cream," he said.

Specifically, the proposed changes to the standards would replace the current 10% milk solids-not-fat (MSNF) requirement for ice cream mix with an equivalent 2.95% dairy protein requirement. This change results in the same amount of dairy protein, without limiting the type of protein to MSNF. The old standards limit the use of whey to 25% of the milk solids requirement; in light of new whey fractionation technologies, the petition will remove the limit on how much whey proteins manufacturers can use in meeting the 2.95% requirement.

The petition would allow for combinations of safe and suitable dairy ingredients that must meet current nutritional requirements — including the minimum protein level.

"These changes would permit and encourage creativity in the product development lab, resulting in new products that will delight consumers," said Wells. "Maintaining the flow of new products is the lifeblood of the ice cream industry."

IICA notes that the proposed changes to the standards would allow ice cream manufacturers to buy more high quality, sophisticated whey products from U.S. ingredients companies, a change that should stimulate the whey market, as well. Newer whey products have become popular among food manufacturers in recent years in such foods as energy bars and beverages, as well as food and beverage products that require protection against freeze-thaw crystallization, or for improved texture in fat-reduced foods and beverages.

IDFA Vice President of Regulatory Affairs Cary Frye emphasized that IICA expects the proposed changes to improve the quality of ice cream products, as a result of the greater flexibility to create new flavors and varieties.

"Ice cream is a food that is extremely sensitive to consumer preference, perceptions of quality and price. Ice cream is an indulgence, and therefore consumers demand the best quality at the best price," said Frye.

The total annual retail value of the frozen dessert industry is estimated at $20 billion. IICA attributes almost all of the market growth over the past 10 years to sales of superpremium and premium ice creams, particularly the innovative, indulgent products. The strongest trends in the freezer case in the past decade include candy inclusions, gourmet coffee flavors and rich flavors such as dulce de leche.

IICA hopes that FDA will consider the petition quickly and publish a proposed rule in the near future.

The July issue of Dairy Facts will cover dairy farmers’ reaction to the new ice cream standards.