Food Safety and Quality Challenges of Creating Novel, Multi-ingredient Dairy Products
By Mark Carter
With booming sales in many market segments and the iconic “Got Milk?” catchphrase, the dairy industry was the marvel of Wall Street and the envy of Madison Avenue throughout the 1990s. While higher fluid milk prices in the first few years of the new millennium diminished some of its luster, the industry’s ability to develop new and innovative products has been crucial in helping it to avoid protracted sales slumps.
From mango-flavored milk to granola-topped yogurt, the dairy industry has taken product formulation to a higher creative level. At the same time, the industry is providing highly discriminating consumers with convenient, nutritious and highly innovative products.
Riding a new crest of success and hoping to further tantalize the palates of health minded consumers, dairy manufacturers are pushing the formulation envelope. Increasingly, companies are incorporating ingredients not commonly associated with dairy components into a products ranging from fluid milk to pudding. While stretching formulation boundaries to new creative dimensions, dairy manufacturers must be mindful of important safety and quality considerations.
Breaking New Boundaries
Recently, an insightful standup comedian appearing on a television talk show reminisced that when he was a child there was only cow’s milk in the milk cooler—and it was a relatively small cooler. Today, he wryly observed, the milk section in supermarkets are half a mile long.
Milk is a staple in the diet of many children. While we usually think of milk as a rather ubiquitous item, dairy based products are smashing dated preconceptions to meet changing market needs. Milk, ice cream and cheese are no longer limited to “vanilla” boundaries such as “chocolate,” “strawberry,” and “American.”
Adding creative and novel ingredients to enhance the eating experience has been an effective strategy for manufacturers to create stimulating products, win new customers and build their brand. With a cursory look at the typical retail dairy case, it is easy to see that leading dairy product manufacturers like Kraft Foods, Dean Foods and Unilever are pushing the envelope far past flavored milks with novel dairy-based products like cultured dairy drinks, or “drinkable yogurts” containing probiotic bacteria like omega-3 fatty acid and inulin, a calcium-absorption-boosting fiber and prebiotic for digestive health, and smoothie-style drinks combining yogurt with fruits, spices and dietary supplements or made with cultured soy yogurt with fruit and vitamin fortification. Other innovative products include cottage cheese with pineapple, raspberry, peach and other fruit toppings; refrigerated coffee creamers flavored with toffee caramel, amaretto and hazelnut; cream cheese infused with ingredients ranging from berries, peaches and vegetables to salmon, honey nut and jalapeno; and ready-to-serve Chai tea products.
For thousands of years, humans have consumed dairy products in various forms. In modern times, we learned dairy products were great vehicles to deliver vital nutritional components to consumers. As a result, an exponential increase in the number of “better for you” products occurred. Today, products that combine health benefits with creative tastes and eye-catching marketing twists represent the next bold step in the evolutionary curve.
Fortification is a long-time fixture in dairy production. Vitamin D fortification in milk is a classic example. Numerous direct health benefits, such as disease prevention, can be derived from consuming fortified products. From isoflavones to probiotics, manufacturers are touting the health benefits of novel ingredients to health conscious consumers. The following section provides a brief overview of some of the more familiar ingredients.
Say Soy. Isoflavones are compounds whose health and wellness benefits are being widely studied. Purported health benefits of isoflavones include reduced risk of heart disease and protection against hormone related disorders such as breast and prostate cancer. Isoflavones are found in many foods, but are primarily derived from soybeans. Soymilk—some would argue “juice”—products have been around since the bygone days of Harvey Kellogg. Novel soymilk products are entering the market and reaching a larger consumer audience.
Soy proteins are excellent candidates for use in dairy/nondairy products. Daidzein and genistein, the two major soy proteins, can be delivered in many forms. Due to their heat stability, they are ideal for use in products that undergo some form of thermal processing.
A study conducted in Thailand evaluated the pharmacokinetic properties of specific isoflavones in beverages versus a pill delivery system. The study found no significant difference between the efficacies in the two delivery methods. This explains the attractiveness of soy-based beverages as a viable health and wellness option.
That’s Chai. Exotic spices are increasingly finding their way into dairy products. One such spice is Chai, a mixture of black tea, spices (cardoman, cinnamon, ginger and peppercorns) and sugar. Renowned for its rich and complex flavor, Chai is indigenous to southern Asia and its popularity is spreading throughout the United States.
Many dairy manufacturers are including Chai in a variety of products, including ice cream. Loaded with healthy antioxidants, Chai by its makeup is a complex and challenging ingredient for manufacturers.
Mighty Omega-3s. The benefits of omega-3 oils are well documented. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the two most frequently referenced oils. Each is derived from certain species of fish. A host of epidemiological studies, clinical investigations and animal experiments indicate that fish oil may posses significant inhibitory effect against various cancers, including cancers of the breast, colon, skin, pancreas, prostate, lung and larynx.
Theoretically it is possible to enrich any food product with omega-3s. However, the addition of omega-3 lipids to foods is easiest with products that already have a liquid fat content. When adding omega-3 oils to food, the percentage of oils added should be reduced by the equivalent amount.
Due to their high degree of unsaturation, omega-3s are highly susceptible to oxidation, even under mild conditions. Hydrogenating omega-3s to protect against rancidity is ineffective because it destroys the double bonds that give them their health properties. This can affect flavor and possibly damage health by increasing free radical formation in the body. The addition of antioxidants such as vitamin E is often used to prevent oxidation. Microencapsulation, another technique that protects oils and guards against damage incurred during processing, renders fish oil products tasteless and odorless.
Pondering Probiotics. Probiotic cultures are arguably the most “dairy” of the novel ingredients currently in vogue. Almost 100 years ago, microbiologists pondered the benefits of certain groups of bacteria. Many of these organisms are commonly encountered during dairy fermentation. Controlling the growth of undesirable organisms, improving immune response, aiding digestion, and possible anticarcinogenic properties are just a few of the many benefits of probiotics. Although probiotic organisms are common fermentative bacteria, their addition to products introduces a new dimension to product complexity.
A wide range of botanicals, exotic fruits, exotic natural flavors, vitamins and minerals must also be included on the novel ingredient list. Gums and stabilizers, which provide key functional properties in quality and stability of products, also bear mention.
From a quality and safety standpoint, it is inherent for dairy manufacturers to do their homework and understand the microbiological, chemical and physical characteristics of these ingredients when used in combination with dairy products.
Managing the Safety and Quality Challenges
The challenges faced by processors increase based on the formulation complexity of new products. Dairy products have well known organoleptic and physical characteristics that are the “standard of identity” for new product introductions. If we take a step back and consider the classic risk assessment processes, it is easier to understand the challenges posed to developers. Traditional dairy products have clearly defined specifications and performance parameters. The Pasteurized Milk Ordinance (PMO) sets clear guidelines for dairy safety.
Basic considerations when using non-dairy ingredients in dairy products include:
• Function in the new product
• Intended use of the product
• Verification of design parameters
Product safety and quality are delivered to the consumer by developing a strong framework early in the creative process. This begins by assessing the risks associated with the new product. To accomplish this, risk profiles associated each ingredient must be compiled utilizing the following factors:
• Intrinsic properties: inherent product characteristics
• Extrinsic properties: external product factors
• Processing: effect on product
• Packaging: effect on product
Different ingredients present a very different set of challenges for product developers. Most quality professionals are familiar with intrinsic properties as they are normally spelled out in product specifications.
At the outset, the first question one must consider is: What is the inherent risk of the ingredient? The first level of risk deals with safety factors, whereas the second level deals with quality. Does the ingredient pose a risk of containing pathogens? If affirmative, can pathogens grow in the ingredient? Soy, for example, can potentially contain Salmonella. Due to the soy’s low water activity, Salmonella will not grow, but the risk still exists.
In addition to microbiological risks, allergenic and toxicological risks must be taken into consideration. For instance, soy is an allergen and Chai contains black tea and other spices that may have been minimally processed. Omega-3s could pose special challenges from an allergenic standpoint. Evidence to date indicates highly refined oils have little risk, further raising the issue of ingredient purity.
Extrinsic factors, such as storage temperature and packaging, greatly affect ingredient quality and safety. This must be considered before transferring them into an unfamiliar matrix. Once these ingredients have been included in a dairy product, producers must determine if the normal quality parameters have changed through an assessment of all phases of product design, including organoleptic acceptability.
Processing plays a huge role in dairy product quality and safety. Each time a new ingredient or component is added, a process must be reviewed. For example, will the addition of a dry ingredient into a dairy mix increase the risk of spoilage due to changed microflora? By increasing the processing temperature for a product, do we modify the microflora, organoleptic characteristics, and nutritional content? These and other important questions must be answered.
Packaging plays a key role in product safety and quality. What may have worked for one variety of dairy products, may not work for another. Packing manufacturers are continuously devising inventive ways to deliver products to consumers in formats that fit into on the go lifestyles of consumers. Examples include multiple formats of single-serve beverages, yogurts and ice creams. Packaging must function as a barrier to microbiological, chemical, and physical contaminants that would degrade product quality and safety.
With the incorporation of new ingredients, it is imperative to consider their physical and chemical interactions with existing packaging materials. Developers must be keenly aware of new off flavors and odors. In partnership, packaging manufacturers and processors consider these questions as part of a product risk profile. Novel ingredients will continue to test their inventiveness and fortitude.
Looking ahead, the popularity of complex dairy products containing novel ingredients will continue. However, food technologists, researchers and developers are still learning about the allergenic and toxicological effects of some novel ingredients. Complex interactions are virtually impossible to anticipate—what may not be a problem in one native population may pose serious health risks to other groups of consumers.
Building on an excellent track record of food safety and quality, the dairy industry is up to the challenge. To continue this momentum, manufacturers must move forward with equal measures of sound science and due diligence. In the meantime, we should seize the opportunity to sit back and enjoy a bowl of soy-enriched ice cream, followed by a sparkling new age beverage featuring an unmistakable hint of Chai!
Mark Carter is General Manager of the Silliker Inc. Food Science Center in South Holland, IL. With 38 laboratories in 10 countries, Silliker is the leading international network of ISO 17025 accredited food testing and consulting laboratories. A graduate of the University of Georgia with a BS in microbiology, he holds an MSA from Columbus State University. Mark is a registered clinical and public health microbiologist with the American Academy of Microbiologists and Chair-elect of the American Society for Microbiology’s Food Microbiology Division. Prior to joining Silliker in 2005, he served as a Section Manager for Microbiology and Food Safety for Kraft Foods North America where he was responsible for the Dairy, Meals, Meat, Food Service and Enhancer product sectors.