Introduction

Commercialized pet food has been evolving since the late 1800s. From rock-hard, flour-based biscuits to the adaptation of extrusion and canning or the most recently developed “fresh-cooked” processes, the processing methods of foods for pets and humans are becoming similar (Bohrer, 2011). Today, the United States pet food industry is estimated to be worth $42 billion and continues to rapidly grow year after year (APPA, 2022). This growth is, in part, driven by an increasing pet population accelerated by the pandemic (APPA, 2022; Euromonitor International, 2022); however, much of the growth and evolution of the pet food industry is arguably in response to a growing bond between humans and their pets (Sable, 2013). As pet owners are increasingly looking for new ways to nourish and delight their pets, the development of new, alternative formats of pet foods offers many advantages to pet owners, including more variety of food choices that typically have a more pleasant appearance and aroma than conventional pet foods. Benefits for the pet from these innovative foods include exceptional palatability and nutrient digestibility as compared with conventional pet food formats (Do et al., 2020; Tanprasertsuk et al., 2021). That said, barriers to the growth of new, alternative pet food formats such as “fresh-cooked” foods do exist. Most notably, the cost of feeding pets a diet solely consisting of “fresh-cooked” foods may be prohibitive for many pet owners (Figure 1). Furthermore, these novel foods bring unique technical challenges to manufacturers that do not exist for conventional kibble and canned pet foods. From securing ingredient supply to ensuring the safety and shelf life of products, manufacturers of “fresh-cooked” pet foods have been challenged to adapt new formulations, processing methods, and supply chain strategies that have not previously existed in the pet food industry. This paper will explore consumer insights that have contributed to the evolution of the pet food industry as well as the unique opportunities that pet food brands face as they seek to satisfy consumer demand for high-quality, humanized pet foods that do not compromise the nutritional adequacy, safety, and sustainability of commercial pet food diets.

Figure 1.

Feeding cost comparisons among premium brands of kibble, wet, “fresh-cooked” at retail, and “fresh-cooked” direct-to-consumer (DTC) pet foods on the market.

History of Commercialized Pet Food

To understand how the pet food industry has evolved to where it is today, we should consider the early development of commercialized pet food. It is believed that dogs were domesticated nearly 16,000 y ago (PFI, 2022). In the Middle Ages, it was common for the wealthy to have cooks dedicated to making meals (typically stews made of grains, vegetables, and some meat and organs) for their hunting dogs (Walsh, 2009; PFI, 2022). In those times, feeding dogs an omnivore diet stemmed from the idea that domesticated dogs should be more civilized than wild, untamed dogs and thereby should eat “like humans” rather than simply eating raw meat. This notion remains today and has arguably been the primary driver behind the growth of the pet food industry.

The first commercial pet foods appeared during the 19th century with the rise of the middle class; thereby, families began having more disposable income, which allowed dogs and cats to be kept as companion animals instead of only as working animals (PFI, 2022; Semple, 2022). In the late 1850s, James Spratt, an American inventor visiting England, noticed that sailors were feeding hard biscuits made of flour, water, and salt to their dogs (FEDIAF, 2019). Spratt took this concept back to the United States and by 1895 had developed a biscuit for dogs that the New York Times acclaimed to be “the principal food” of show dogs (TCKC, 2018; PFI, 2022). The dog biscuit has evolved since then, most notably in 1907, when Carleton Ellis created a new milk-based dog biscuit shaped like a bone (TCKC, 2018). In 1908, bone-shaped biscuits were being sold by the F.H. Bennett Biscuit Company, and Milk-Bone is still arguably the most popular dog biscuit brand in America today (Slater, 2014; TCKC, 2018). The F.H. Bennett Biscuit Company (currently Nabisco) was acquired by the National Biscuit Company in 1931, becoming the first major human food company to enter the pet food market. Consequently, that opened the door for pet foods to be sold in grocery stores rather than only in feed stores, an appalling concept to grocery stores at first (Phillips, 2007). Interestingly, the “channel wars” persist today as some brands reverted to selling only in pet specialty store channels, but many have expanded back to the general retail outlets, and the online versus offline channels continue to reflect different purchasing patterns (Lim, 2017; Kwak and Cha, 2021).

In 1922, the Chappel brothers of Rockford, Illinois, introduced the first canned dog food, Ken-L Ration, which was primarily made of horse meat. Interestingly, this canned food became so successful by the mid-1930s that the company was breeding horses for their meat (Phillips, 2007). Canned dog food had gained a 90% share of the market by 1941, and Quaker Oats purchased Ken-L Ration in 1942 (Phillips, 2007). The US government began rationing tin and meat during World War II, leading to popularity growth of pet food alternatives such as dry foods (Phillips, 2007). Around the same time, Clarence Gaines, founder of the Gaines Food Company, was selling a new dry dog formula called “Dog Meal” in 100 lb bags (Phillips, 2007). Similar to Ken-L Ration, Gaines leveraged dog show advertising to promote his brand; subsequently, the Gaines Food Company developed national attention and was acquired by General Foods in 1943 (Phillips, 2007). In 1961, General Foods introduced Gaines-Burgers, a soft-moist, hamburger-shaped patty for dogs that was shelf-stable and individually wrapped (Phillips, 2007). In the 1950s, the Ralston Purina Company, manufacturer of whole-grain cereals as well as several “Chow” brands of animal food, including Purina Dog Chow and Purina Cat Chow, began using an extruder to make their Chex cereal (Phillips, 2007; Semple, 2022). In this process, the ingredients were mixed and cooked under high pressure, then puffed up with air, which allowed the crispiness of the product to be maintained in milk (Phillips, 2007). The pet food division of Ralston Purina borrowed an extruder from the cereal division to address complaints about the appearance, texture, and digestibility of the dry dog food. Experimentation with extrusion technology eventually led to an improved version of Purina Dog Chow in 1957, which quickly became the leading brand of dog food in the United States because of improved palatability and expanded texture, which made the bags of food larger than competitors’ products for the same weight of food (Phillips, 2007). Since that time, extrusion has remained the dominant form of processing for the pet food industry, although this is beginning to change.

Throughout the early history of the pet food industry, cats received relatively little attention. Oftentimes, labels suggested that foods were suitable for both dogs and cats, although little was known about specific nutritional requirements of cats. Early cat foods were primarily sold in 1 lb cans and produced near the coast where fish were abundantly available (Phillips, 2007). The invention of smaller cans opened up the cat food market, and Nestlé launched Fancy Feast Gourmet in 3 oz cans in 1982, with many ingredient combinations beyond fish meant to attract the finical cat (Phillips, 2007). Since then, pet food companies learned that cats will also eat semi-moist and dry foods. Another notable shift in the pet food industry came in the mid-1970s when companies like Hill’s, Iams, and Nutro began selling their “super premium” brands (≥ 20% higher prices than average pet food products) through veterinarians, breeders, pet stores, and kennels with the idea that the pet owner could receive education about brand benefits and features (Phillips, 2007; Pirisch et al., 2017). Generic (unbranded), popular (variable formulation to allow lower cost), premium (consistent formulation with high-quality ingredients), super premium, and private-label (grocery or commercial retail) are a few of the more common categories for pet food (Karr-Lilienthal, 2019). Most recently, societal shifts have resulted in the terminology of pet owners as “pet parents” with their animals considered as children and referred to as “fur babies,” and the foods they select for their pets reflect this sentiment (Greenebaum, 2004; Power, 2008; German, 2015; van Herwijnen et al., 2018; Owens and Grauerholz, 2019; Donadelli et al., 2020).

Industry Landscape and Consumer Insights

In 2020, the US pet care market surpassed $100 billion for the first time ever, and nearly half of this spending ($42 billion) was in pet food, which represented a 9.7% increase compared with 2019 (APPA, 2022). This expansion is partly due to the rapid growth of the US pet population, which continued to rise each year (Euromonitor International, 2022). According to the 2021 to 2022 American Pet Products Association (APPA) National Pet Owners Survey, 70% of US households (90.5 million homes) own a pet (APPA, 2022). Pet population growth was accelerated by the pandemic (Euromonitor International, 2022). In 2020, there was a 4.7% increase in cats and dogs as compared with 2019, which was double that of any other year in the past 15 y (Euromonitor International, 2022). Pet ownership is higher among younger generations, with 76% of millennials (defined as being born between 1981 and 1996) reportedly owning a pet (Dimock, 2019; APPA, 2022). In 2020, 54% of households included at least 1 dog, whereas 35% of households included at least 1 cat (APPA, 2022). In response, global pet food production has increased to meet the rising demand from pet population growth. According to Alltech’s 2022 Global Feed Survey and Agri-Food Outlook report, pet food production in North America was 10.6 million metric tons in 2021, representing a 12.7% increase from 2020, the highest increase among all feed sectors (Alltech, 2022). This speaks to the resiliency of the pet food industry against challenges from COVID-19, including reduced labor and supply chain disruptions. Corresponding to the increasing pet population, pet food humanization and product premiumization continue to drive pet owners to pay more for the foods they feed their pets (Bohrer, 2011). Although human health issues are not necessarily reflected similarly in companion animals, pet owners are increasingly expecting functional claims in pet food to resemble those in human food with emphasis shown toward health or disease improvements, such as immune and digestive health, leading to pet food products resembling human trends and increased “humanization” (Clemens, 2014; Schleicher et al., 2019). According to a recent Packaged Facts (2022) survey, more than 90% of pet owners of all ages consider their pets to be part of the family. Additionally, a growing body of evidence suggests that pets play a key role in mental health and well-being, especially during difficult times (Brooks et al., 2018; Powell et al., 2019; Grajfoner et al., 2021). A recent study concluded that owning a dog during the COVID-19 pandemic may have provided people with a stronger sense of social support because they showed decreased depression scores as compared with people who did not own a dog but would be interested in owning one in the future (Martin et al., 2021).

Petfoodindustry.com recently reported the top business and nutrition trends currently driving growth and innovation in the pet food market (Beaton, 2022; Phillips-Donaldson, 2022). The first trend identified was sustainability, which extends well beyond recyclable packaging. The Pet Sustainability Coalition outlined a 4-factor framework including environmental impact, social impact, nutrition, and animal welfare, and modern consumers are looking for brands to tell a full sustainability story encompassing all 4 of these factors (Tyler, 2021b). According to a recent survey conducted by Cargill (2022), more than half (55%) of global consumers are more likely to purchase a packaged food item labeled with a sustainability claim, which is up 4 points from a similar survey in 2019.

Transparency was identified as the second industry trend. Pet owners are seeking more information about the product they are purchasing. They seek insight into the origin, safety, and nutrition of ingredients used in foods consumed by pets as well as foods that the pet owners are consuming themselves. From a nutritional perspective, the pandemic has placed more focus on the importance of a healthy diet to support a healthy lifestyle. Just as they try to make healthier food choices for themselves, pet owners are increasingly selecting pet foods with overall “health and wellness” in mind. Pet owners, especially those of the younger generation, are increasingly willing to try new and alternative ingredients, particularly if they support other values such as sustainability or health and wellness. Moreover, this is demonstrated by the growth of both plant-based and insect-based pet foods (Tyler, 2021a). In 2021, insect-based pet foods made up approximately 7% of the global pet food market and were expected to grow 9.3% between 2021 and 2031 to reach $17.29 billion (FMI, 2021). A recent study from the University of Guelph in Canada concluded that pet owners tend to rely on their own dietary preferences when selecting foods for their pets. Furthermore, consumers likely look for similar gluten-free, organic, or grain-free diet characteristics in the dry dog food they purchase (Banton et al., 2021).

The final trend reported to be driving innovation in pet food is functional ingredients (Beaton, 2022). Rather than turning to medicines, there is an increased interest in food-based solutions to support pet health as related to common ailments such as hip/joint, skin/coat, and digestive health (Clemens, 2014; Schleicher et al., 2019). Considering all these trends, pet owners are paying closer attention to what they are feeding their pets and are making pet food decisions that reflect these sentiments, likely wondering, “Is feeding kibble enough?”

The change in pet food purchase decisions is clearly reflected in the market data by segment. Sales are up across the board, with dry kibble still representing nearly 50% of the category; however, sales of wet pet food and emerging pet food formats, such as refrigerated and frozen, are growing rapidly. According to Nielsen data between December 2020 and December 2021, dry dog and cat food sales grew 5.7% and 6.4%, respectively, whereas wet dog and cat food grew 13.7% and 12.3%, respectively, taking overall market share away from dry pet food (Nielsen Company, 2022). Although emerging pet food formats (e.g., frozen, refrigerated, “fresh” foods) represent less than 3% of the market, they exhibited strong growth rates ranging from 13.4% to 26.6% during the same time frame. Specifically, in the 12 mo ending December 2021, refrigerated pet foods grew nearly 26%, which is on top of double-digit growth rates for the last 4 y. Taken together, this information suggests that alternative super premium pet foods have been increasing in popularity for several years (Pirsich et al., 2017). That said, the pandemic has possibly fueled the growth of these pet food categories as people have been spending more time with their pets and paying closer attention to what they are feeding them. The renewed interest in wet pet food and the emergence of alternative formats also suggest that pet owners may be shifting toward the practice of feeding more than one type of food. This is especially evident in the younger generations that are looking to add variety and diversity to their pets’ food bowls.

In a recent Packaged Facts survey, 29% of the millennials/Gen Z demographic reportedly used alternative pet food formats compared with 13% of baby boomers (Packaged Facts, 2022). This usage difference may be partially attributed to an awareness or perception that these alternative formats are less processed and that minimally processed foods may be healthier for pets. Brands and retailers are responding as a result of this shift in consumer purchasing behaviors. Frozen pet food is actually not new to the market; brands like Bil-Jac have been in the space for over 75 y (Bil-Jac, 2022). The refrigerated pet food category at retail is currently dominated by one manufacturer, Freshpet, who currently has nearly a 99% share of the segment and is projecting to grow nearly 35% in 2022 (Euromonitor, 2022; Tyler, 2022a). Mars recently entered the refrigerated category at retail with Cesar Fresh Chef and captured 0.34% of this segment as of December 2021. Additionally, private brand options are beginning to emerge, including the Pure Balance offering from retail giant Walmart.

Similar to e-commerce, direct-to-consumer (DTC) pet food sales are increasingly gaining momentum with many new DTC pet food companies emerging in recent years (Phillips-Donaldson, 2020; Wall, 2022a). This was bolstered by the COVID-19 pandemic, when supply chain challenges, a demand spike, and closer relationships with their pets drove many pet owners to shift the way they shopped for pet food. Across all categories, including pet food, people are looking for convenient shopping options that allow them to shop from home, which has led to a rise in popularity of subscription services (Alvo, 2021; Roberts, 2022; Wall, 2022a). Some large pet food companies are taking notice, as evidenced by Mars Petcare’s recent purchase of Nom Nom, one of the major “fresh-cooked” pet food brands available for home delivery (Tse, 2022).

Pet Food Processing Methods

Often following in the footsteps of human food processing, pet food processing methods have evolved to meet changes in consumer demand. Baking was one of the first methods used to make pet food, and this process involves cooking at high temperatures for a relatively short time or until enough moisture has been removed to make the food shelf-stable (Gibson and Sajid, 2013). Extrusion is a versatile processing method commonly used for snacks and cereals in which ingredients are steam-heated, mixed under pressure, forced through a die, and cut into formed kibbles (Gibson and Sajid, 2013). The kibble expands and moisture is released as the product exits the die. The kibbles are further heated and dried in an oven to reduce moisture content (usually below 10%). Extruded foods are typically high in carbohydrates because the starch is needed for kibble expansion. In canning (also known as retort processing), the ingredients (which are primarily meat but may also contain grains, vegetables, and fruits) go through a series of steps: mixing, heating, can filling (or another retort-stable packaging), and hermetic sealing (Hagen-Plantinga et al., 2017). The sealed packages are cooked at high temperatures under pressure in a retort until they become commercially sterile. The most recent pet food processing method that has evolved from human food processing closely resembles deli-meat processing and represents a “gently cooked” or “fresh-cooked” process (Bohrer, 2011; Algya et al., 2018). Similar to canned products, the primary ingredients are typically meat with visible inclusions of fruits and vegetables. Many of these foods are cooked by steam, without pressure, just long enough to cook the proteins and destroy pathogenic and spoilage bacteria. Baked, extruded, and canned foods all offer convenience for pet owners as they can be stored at room temperature with longer shelf lives that make them well suited for buying in bulk, whereas “fresh-cooked” pet foods must be stored in the refrigerator or freezer and have a relatively short shelf life compared with traditional formats (Bohrer, 2011).

As we seek to differentiate the processing technologies used to make pet food, it is important to understand that food processing can have a desirable or undesirable impact on pet food (Sadler et al., 2021). In almost all cases, pet food processing extends the shelf life of foods by destroying microorganisms or removing moisture to slow spoilage reactions during shelf life. At the same time, heat processing can degrade nutrients, particularly vitamins present in the foods (Tran et al., 2008). Processing often improves both the flavor and texture of foods but may also result in the formation of flavors and colors that are less desirable than the pre-processed versions. Many food ingredients, especially plant-based ingredients, can contain antinutritional factors that are normally destroyed during processing, although excessive heating can cause formation of other antinutritional factors, such as Maillard reaction products, which may have negative health implications (Lund and Ray, 2017). Finally, some nutrients, especially carbohydrates, become more digestible during cooking, whereas other nutrients, including protein and carbohydrates, can become less digestible under more extreme heat processing conditions (FAO, 1998; Anju et al., 2011).

The “Fresh-Cooked” Difference

Looking to the Future

The size of the cat food market has lagged behind the dog food market because cats consume less than dogs. That said, the US cat population is on pace to exceed the dog population, presenting a ripe opportunity for companies to innovate (Euromonitor International, 2022). In 2021, US retail sales of cat food reached $12.1 billion, which is up 6.6% compared with sales in 2020 (Packaged Facts, 2021; Wall, 2022b). Moreover, given that cats are obligate carnivores, it stands to reason they would benefit more than dogs with a shift to increased meat or “fresh” food formats that more closely resemble their natural prey. Despite these potential benefits, innovation in refrigerated and frozen cat food seems to be lagging behind options available for dogs. Taken together, these could be significant opportunities for brands to differentiate themselves in this market space to delight both cats and cat parents.

Consumer consideration of the broad definition of sustainability is another critical evaluation for new pet food innovation. With the estimation that cats and dogs consume ∼25% of all animal-derived calories produced in the US, the pet food industry has an opportunity to make a significant impact on the sustainability of our food supply chain (Okin, 2017). As the humanization of pet food progresses, there will be increased competition for ingredients, especially proteins, and the challenges associated with feeding a growing human population will be exacerbated by the need to feed a growing pet population. Importantly, pets have unique nutritional requirements compared with humans, so this must also be considered.

In conclusion, pet food is evolving to become more similar to human food as we increasingly consider pets to be part of our family. Opportunities exist for new innovation, responsible marketing, and product development to meet the changing demands of pet owners. Because pet owners will continue to demand transparency and higher quality foods for their pets, brands must find innovative solutions without compromising the environmental impact, safety, or nutritional value of the diets. Moving forward, there should be an industry-wide effort to educate pet owners on the importance of a science-based approach to formulation and selection of ingredients that meet the animal’s nutritional requirements without negatively impacting the environment.