This article was published in the July 2024 issue of Pet Food Processing. Read it and other articles from this issue in our July digital edition.
According to a 2018 survey by Banfield, food allergies in pets are far less common than flea and environmental allergies. Yet, as pet owners pay closer attention to their beloved pets’ health, wellness and nutrition, many are seeking limited-ingredient, free-from or clean-label options that they believe can help address perceived food allergies and sensitivities.
“Common food allergens are really a function of how common ingredients are found in food,” explained Gary Richter, DVM, chief executive officer of Ultimate Pet Nutrition, Los Angeles. “In other words, the more pets are eating a specific food item, the greater the chance they develop a sensitivity to it.”
Protein sources like chicken and beef are some of the most common food allergens for dogs and fish is the most common allergen for cats, according to RuthAnn Lobos, DVM, CCRT, CVAT, senior veterinarian at Nestlé Purina PetCare, St. Louis. This is largely because they are the most common proteins used in pet food. Scientific evidence points to dairy and wheat as other common canine allergens.
“A food allergy is a hypersensitivity reaction in the immune system that occurs when exposed to a certain food,” explained Crystal Wilcoxen, associate director of product development, H&H Group (Solid Gold and Zesty Paws). “These foods cause the dog’s immune system to overreact and may lead to itching, gastrointestinal distress and other health problems. Food allergies should not be confused with a food intolerance, such as a lactose intolerance.”
Reactions to food allergens include itching of the paws, abdomen, groin, face or ears, as well as gastrointestinal disturbances like flatulence and diarrhea, shared Heather Mendoza, Ph.D., director of research and development, Nulo, Austin, Texas. A true food allergy is far less common than environmental allergies and food sensitivities, according to Jennifer Freeman, MS, RVTg, Director of Nutritional Science, Natural Balance Pet Foods, San Diego. Most dogs who have a food sensitivity will exhibit symptoms of digestive upset. However, in some dogs they can also develop dermatological symptoms such as skin irritation, itching, or even ear infections, Freeman said.
With many limited-ingredient pet diets being higher in carbs and lower in protein, Nulo sought to reverse these metrics by creating allergen-friendly diets that are still high in protein.
|“Adverse food reactions can be the result of an immune response (food allergy) or can occur because of metabolic incompatibilities with food (food intolerances),” Mendoza added. “True food allergies can result from genetic predisposition, but they have also been linked to the condition of the gut lining (i.e. gut permeability) and dysbiosis of the gut microbiome.”
Many limited-ingredient, minimally processed and “hypoallergenic” diets have arose as a way to satiate food-sensitive pets without compromising quality nutrition. However, it’s important to note that the term “hypoallergenic” on a pet food label is highly subjective, as each pet experiences different allergic reactions to different food ingredients.
“Hypoallergenic is a confusing term,” Richter said. “Any dog or cat can have a sensitivity to any ingredient.”
Therefore, developing food allergy-friendly pet foods and treats is as much about including specific ingredients as it is about leaving others out of the mix altogether.
“The simplest path to an allergy-friendly food is to use more novel proteins and less of the ‘top culprit’ ingredients triggering allergies,” said Jon Wooner, pet products director, North Coast Seafoods, Boston.
Picking the right proteins
Because proteins are often the culprit of food allergies in pets, incorporating novel proteins — protein sources that a dog or cat has not eaten before — is a common approach to formulating these types of diets.
“Novel proteins can range from more traditional sources like lamb or duck to exotic meats like kangaroo or insect protein,” Mendoza shared. “Whether a protein is novel to a specific pet depends on their diet history and previous exposure to that particular ingredient.”
Minimal processing methods, like those used for fresh, freeze-dried and air-dried pet food formats, could help lessen the impact of protein-related allergens in finished pet food, according to Gary Richter, DVM, of Ultimate Pet Nutrition.
|For example, if a pet hasn’t formerly eaten fish, a marine-based diet may be a good option, according to Wooner. These diets are naturally rich in Omega 3 and 6 fatty acids, both of which are known to mitigate inflammation, support skin and coat health, digestion and the immune system. This not only offers pets a novel source of protein to mitigate food allergies and sensitivities but can also address some of the negative symptoms of food allergies.
Lobos noted vitamin A and zinc have also been shown to support skin and coat health. Additionally, formulating products for gut health and digestion support can help pets manage the symptoms of food allergies and sensitivities.
“Solid Gold prioritizes ingredients that support gut health, such as pumpkin, clean animal plasma, probiotics, and prebiotic fibers to offer nutritious recipes that are still mindful of common food allergens,” Wilcoxen shared.
As protein sources for pets evolve, new innovations are offering processors more alternative options. Early research has pointed to insect protein as a hypoallergenic protein source for dogs and cats, and hydrolyzed protein has emerged as another promising solution for addressing food sensitivities.
“Hydrolyzed protein diets, for example, can deliver proteins that have been processed into small peptides instead of intact proteins and large polypeptides and are therefore less likely to be recognized by the immune system,” Mendoza explained.
Emerging pet food formats such as fresh and minimally processed also have a role in reducing common food allergy reactions in pets, according to Richter.
“Feeding fresh food decreases the relative ‘reactivity’ of proteins. In other words, they can be more allergenic when they are highly processed,” Richter said. “In addition, having pets rotate through different diets over time rather than them eating the same food for years can reduce the development of sensitivities.”
Limited ingredients are limiting
Formulating a dog or cat diet is like assembling a puzzle — you need all the pieces to fit together perfectly in order to get the full picture or, in this case, a complete-and-balanced diet. Today, though, “complete-and-balanced” has become the baseline as consumers increasingly seek functional options that address their furry companions’ health issues and nutritional uniquities.
This makes the formulation puzzle all the more complicated. Not only must product developers strike a balance that makes sense nutritionally and in process, but they must also consider specific need states, consumer preferences, and what is possible within the available ingredient supply.
“Less is more” is the motto behind Natural Balance’s limited-ingredient diets, which are touted to support pets with sensitive skin and stomachs.
|“Notably, some of the more allergy-friendly, novel ingredients can be more difficult to source,” Wooner said. “For example, high-quality, sustainable fish can be quite challenging (and expensive) to procure for use in pet food diets.”
The rise of clean-label nutrition has led to a surge in limited-ingredient pet food sales, according to Mendoza, which checks boxes for both more recognizable and more selective ingredient labels. Formulating with limited ingredients is challenging, however, and doing so in a premium format often creates more complexity.
“We knew when entering this category that ‘simple’ is rarely easy, and that we would need to find a way to innovate in a space that been dominated by brands that focus on value over premiumization, which has contributed to the growing demand for limited-ingredient diets with enhanced customization and functionality,” she said.
Cost is another barrier for formulating clean-label, limited-ingredient or allergen-friendly diets for pets. Rising inflation has upped the price of proteins and other core pet food ingredients already, and those seeking novel sources or producing more premium formats are likely to experience even higher price tags.
“Well-formulated, minimally processed diets are going to be more expensive to manufacture, and thus consumer costs will increase,” Richter said. “This is something all pet food companies have to contend with.”
When formulating fresh or minimally processed diets, manufacturers must understand the food safety nuances of these emerging categories and what is needed to prevent bacterial contamination and pathogens. It’s also critical to keep cross contamination under control when formulating regular diets in the same facility as allergen-free or limited ingredient diets.
“Having a thorough quality assurance protocol is essential when making a truly hypoallergenic diet,” said RuthAnn Lobos, DVM, of Nestlé Purina PetCare.
“Cross contamination in storing of ingredients and production of the food in the dry and wet manufacturing process is likely the biggest challenge in over-the-counter diets,” Lobos said. “Having a thorough quality assurance protocol is essential when making a truly hypoallergenic diet, which includes regular ingredient testing and protected production areas.”
Solutions for sensitive pets
Luckily for sensitive pets, industry innovators are on the ball in answering demand for food allergy- and sensitivity-friendly nutrition. Many of these solutions take a single-source or novel protein, limited-ingredient approach.
Natural Balance, for example, built its reputation on limited-ingredient pet food recipes. Its limited-ingredient portfolio includes dry and wet diets for dogs and cats with single animal protein source and limited carbohydrate recipes that are offered in either grain-free or grain-inclusive options. A vegetarian formula is also offered that has no added animal protein sources.
“Each diet is completely balanced with essential nutrients, such as Omega 3 and Omega 6 fatty acids to help support healthy skin and coat, fiber to support digestive health, taurine to support a healthy heart, Calcium and Phosphorous to support strong bones, and vitamin E to support a healthy immune system,” Freeman said.
Chicken and beef are two of the most popular protein sources for dog food, and also the top two food allergens for canines. Dogs exhibiting signs of a food allergy to these proteins could do well on a fish-based diet.
|Solid Gold offers two sensitive formulas, one of which is its Leaping Waters Cold Water Salmon & Vegetable Recipe single-source protein diet that is free from chicken, gluten and grains. The company’s Green Cow formula recently made its return to the market, touting New Zealand-sourced green beef tripe as a vehicle for delivering palatability, natural plant matter, gastric juices and digestive enzymes, Wilcoxen shared.
“This recipe is also powered by nutrientboost™, which provides a source of proteins, amino acids and antibodies that help support nutrient absorption, gut health and immunity,” she added.
At Purina, a comprehensive suite of Pro Plan Veterinary Diets aims to address various need states in dogs and cats, and the company’s HA Hydrolyzed Formulas fit right in. These diets were designed specifically to reduce the likelihood of adverse food reactions in dogs by leveraging hydrolyzed protein sources and antioxidants, according to Lobos.
Purina also offers its Pro Plan Sensitive Skin and Stomach formulas without a veterinary prescription. Each formula in this line is designed to support pets with food sensitivities through easily digestible nutrition fortified with ingredients that support skin and coat health.
Nulo prioritized protein content when formulating its limited-ingredient recipes. The company’s Limited+ line features recipes with as much as 76% single-source, animal-based proteins that are entirely free from chicken, egg, beef, corn, wheat and soy. These diets also deliver probiotics to bolster the gut microbiome, as well as a fiber blend for good stool quality.
“When we first decided to launch a line of limited ingredient diets, we set out to apply our high-meat, low-carb nutritional philosophy to the category,” Mendoza noted. “Most of the limited ingredient diets today are the opposite: low-meat, high-carb, and so focused on the number of ingredients in them that they lose sight of the larger picture of the other supporting elements that pets need.”
The philosophy behind Ultimate Pet Nutrition’s food allergy-friendly formulations is centered around minimal processing methods and single protein diets.
“Foods that have multiple protein sources increase the chances of a pet having a negative reaction to something in the food,” said Gary Richter, DVM, of Ultimate Pet Nutrition.
“This way, owners are able to easily avoid proteins their dog doesn’t do well on,” Richter explained. “Foods that have multiple protein sources increase the chances of a pet having a negative reaction to something in the food.”
According to Richter, the company’s freeze-dried diets are lower in advanced glycation products (AGEs) and Maillard reaction products (MRPs), both chemical compounds known to cause inflammation in the body. By taking a minimally processed approach, Ultimate Pet Nutrition is able to avoid these unsavory compounds, which are the result of high-heat processing seen in kibble and canned diets.
North Coast Seafoods’ two pet food brands — Simply Naked, which is sold in the pet specialty channel, and Boat to Bowl, which can be found in the food, drug and mass retail space — specialize in single-protein recipes and are free from chicken, chicken fat, beef, turkey, or animal byproducts. Both brands offer grain-free and grain-inclusive options.
All in all, the nutritional needs of pets vary from tail to tail, and it’s always a good idea for a pet owner to consult a veterinary professional before making drastic diet changes.
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