Greg Aldrich

Kansas State University | KSU · Department of Grain Science and Industry

The global pet food industry continues to grow being fueled by increased pet ownership, higher disposable income of pet owners, and a growing demand for premium products. While this growth has attracted increased interest of researchers in animal nutrition and product formulation, the overall body of management and economic literature to guide prod...

Co-products from the ethanol industry, such as distillers dried grains with solubles (DDGS), can provide alternative protein sources for pet food. Corn fermented protein (CFP) is produced using post-fermentation technology to split the protein and yeast from fiber prior to drying. This results in a higher protein ingredient compared to DDGS, increa...

Different food processing parameters may alter starch granule structure and its cooking degree. With lower thermomechanical energy, more resistant starch (RS) is retained in the food, which may benefit gastrointestinal (GI) health. The objective of this study was to determine the effect of food processing on dietary utilization and dog gut health....

Simple Summary Soybean is a dominant oilseed in the U.S. Although soybeans are valuable ingredients for dogs and cats, soybean use in current pet foods has been low. The research was conducted to answer this question: What effects, if any, do soybean ingredients in dog or cat diets have on animal health and nutrition, palatability, feeding behavior...

As the demand for dog food production continues to rise, along with the number of dogs per household in the US, sustainable ingredients must be considered for the pet food industry. Consumers have a negative perspective when it comes to animal by-products in their pet’s food. However, animal by-products contribute a quality source of dietary protei...

Pet food ingredients that bring extra nutrition and health benefits are much better accepted than being simply an economic choice by the manufacturer. Microbially enhanced protein (MEP) from soybeans is a fermented ingredient that is believed to promote nutrient utilization. The objective of this study was to determine the effect of increasing leve...

New opportunities to upcycle co-products from the food industry into high-value pet food ingredients exist with ingredients such as dried bakery products (DBP), a granular coarse meal from heated and dried bakery products. It has yet to be reported for use in pet food. The objective of the study was to determine variations in the nutrient compositi...

To promote sustainability, the pet food industry could use fermented co-products from ethanol and beer production as ingredients. However, these ingredients may impact the appearance, smell, and taste of the final product. The aim of this study was to analyze the sensory characteristics of extruded dog kibble produced with fermented co-products. Fo...

Ingredients that provide health benefits are popular in the pet food industry. Sorghum contains polyphenols which are found in the pericarp. These polyphenols may provide health benefits due to their antioxidant properties, which increase the benefit of sorghum in pet food. Few pet food studies have evaluated the antioxidant capacity of sorghum dif...

Sustainability is one of the trending keywords in the pet food industry today. Utilizing protein-rich fermented co-products such as corn fermented protein (CFP) can promote sustainable pet food. However, co-product ingredients have been avoided in pet food due to negative consumer perception. Unlike traditional dried distillers grain, corn fermente...

Semi-moist pet foods contain moisture levels ranging from 15 to 40%, making them ideal for mold growth and mycotoxin production. To control spoilage, synthetic mold inhibitors such as potassium sorbate have been used, but consumers prefer “natural” preservatives. Whey fermentate (WPF) is an efficient antifungal, but it requires large doses. Therefo...

The storage mite Tyrophagus putrescentiae infests a wide range of food products including pet food. Control of this mite depends on chemical methods such as fumigation and spraying with insecticides. Methyl bromide was used as a fumigant for high-value stored products, especially to control mite infestation in dry-cured hams and cheeses, but it is...

Pet‐food industry growth and demand for specialized product offerings have generated new opportunities for companies to enhance their competitiveness and profitability through effective product differentiation. Recent rise in e‐commerce and technological advancements for capturing and analyzing online customer review data provide new opportunities...

Simple Summary Corn-fermented protein, a co-product of ethanol production, can be utilized as a protein source for pet food. Currently, there are no studies that have evaluated the impact of this ingredient on the fecal microbiota of dogs, an indicator of animal health. The overall richness and diversity of the fecal microbiota were maintained when...

The inclusion of yeast in pet food can provide health benefits and increase palatability. Corn fermented protein is a co-product from ethanol production which contains approximately 20-25% yeast. The objective of this study was to determine the effects of the yeast in CFP on diet production and utilization when fed to healthy adult cats. The four e...

Traditional distillers dried grains, co-products from the ethanol industry, can be utilized as sustainable ingredients for pet food. However, negative consumer perception prevents their widespread use. Corn fermented protein (CFP) is produced using post-fermentation separation technology, resulting in a high protein ingredient, which may increase c...

There has been increased interest among pet owners to feed vegetarian diets to their pets. However, the primary protein sources used in pet food today are animal based, warranting a need to evaluate novel plant-based ingredients to meet the protein demand. Corn fermented protein (CFP), a coproduct from ethanol production, may provide a plant-based...

Fat has high energy density and is considered one of the primary energy sources for dogs, however, increasing fat level in dry dog food has been challenging due to the lubrication and limitation of the coating system. The objective was to determine the effect of whole soybeans (WSB) on nutrient digestibility, stool quality, and palatability by dogs...

Introduction Rigid cans were the traditional container for canned cat foods, but semi-rigid trays/tubs and flexible pouches are popular options as well. Despite this, little is published on the effects of canned cat food container characteristics on thermal processing and retention of B-vitamins. Therefore, the objective was to evaluate the effects...

Soybean oligosaccharides (OS) have been recognized as a prebiotic that can be fermented in the colon, resulting in short-chain fatty acid (SCFA) production that can be used as an energy source for colonocytes, supporting cell differentiation and gut health. The objective was to determine the effects of WSBOS on in vitro fermentation, using dog fece...

Liquid smoke is a naturally derived flavor component and preservative with known antimicrobial properties. To our knowledge, there is a paucity of information on antifungal potential of liquid smoke against toxigenic fungi like Aspergillus flavus that produce mycotoxins in human and pet foods. Semi-moist pet food with high moisture content (20–30%)...

Salmonella-contaminated pet foods could potentially become a source of human salmonellosis. This study evaluated the survival of Salmonella without and with the addition of acidulants in different fat types (chicken fat (CF), canola oil (CO), Menhaden fish oil (FO), lard (La), and tallow (Ta)) commonly used to coat dry pet food kibbles. The minimum...

Many fiber ingredients are used by the pet food industry; however, little data are available regarding the fermentation characteristics of alternative fibers currently being used. The objectives of this study were to determine organic matter disappearance (OMD) and postbiotic production from various fruit and vegetable fiber sources using an in vit...

Most pet foods utilize traditional ingredients like corn, wheat, and soy. These ingredients and other grains, such as distillers dried grains (DDG), have been used by the pet food industry. Corn fermented protein (CFP) is a nutrient dense enhancement on DDG but has not been evaluated in pet food. Therefore, it was the objective of this study to det...

There is an increasing demand for raw meat-based diets (RMBDs) for dogs, but these foods cannot be heat-pasteurized. Thus, the objective of this study was to evaluate the antimicrobial efficacy of encapsulated and dry-plated glucono delta lactone (GDL), citric acid (CA), and lactic acid (LA) when challenged against Salmonella enterica inoculated in...

Post-processing operations of extruded pet food kibbles involve coating the product with fats and flavorings. These processes increase the risk for cross-contamination with food-borne pathogens such as Salmonella and Shiga toxin-producing Escherichia coli (STEC), and mycotoxin-producing molds such as Aspergillus spp. after the thermal kill step. In...

Contaminated surfaces can transmit pathogens to food in industrial and domestic food-handling environments. Exposure to pathogens on food contact surfaces may take place via the cross-contamination of pathogens during postprocessing activities. Formaldehyde-based commercial sanitizers in recent years are less commonly being used within food manufac...

Yeast-derived 1,3/1,6 beta-glucans may alter host immunity to produce robust and quickly resolved responses that align with companion animal health goals. In adult dogs, immunomodulation by yeast 1,3/1,6 beta-glucans in extruded kibble diet have not been well-documented. The study objective was to evaluate systemic immune responses in dogs fed kibb...

Oral supplementation of β-glucans may be able to improve the health of companion animals. However, little is understood regarding the effects of yeast β-glucan on diet processing and intestinal function. Therefore, the objectives of this research were to determine the carry through of yeast β-glucan during extruded diet production and its impact on...

Introduction Low thiamin levels in thermally processed canned cat foods are concerning for the pet food industry. However, there is little information on storage stability of thiamin in this food format or if inclusion of select ingredients, such as dried yeasts, has an effect. Therefore, the objective was to evaluate the storage stability of thiam...

Raw meat-based diets (RMBDs) or sometimes described as biologically appropriate raw food (BARFs) are gaining in popularity amongst dog and cat owners. These pet guardians prefer their animals to eat minimally processed and more “natural” foods instead of highly heat-processed diets manufactured with synthetic preservatives. The market for RMBDs for...

Increasing the fat amount of the ration during extrusion can negatively affect product density and product expansion. Ingredients, like whole soybeans (WSB), which are high in fat may increase energy density while avoiding production issues. The objective of this study was to determine the effect of WSB on extrusion and product characteristics of d...

Dried distillers’ grains, co-products from the ethanol industry, may provide sustainable ingredients for pet food. Due to new post-fermentation separation techniques, corn fermented protein (CFP) is higher in protein and lower in fiber compared to traditional dried distillers’ grains, increasing its appeal for inclusion into pet food. Therefore, th...

The objective of this work was to evaluate the use of a Torula yeast on diet processing, palatability, and total tract nutrient digestibility in extruded feline diets. Four dietary treatments were compared, differing by protein source: Torula yeast (TY), pea protein concentrate (PP), soybean meal (SM), and chicken meal (CM). Diets were produced usi...

There is little information regarding dogs’ preference for a given flavor, especially in water. Therefore, the objective of this study was to validate the method of using a consumption test to determine the dogs’ ability to discriminate water-based flavors. There were three phases of the study to validate the model using water as a flavor carrier....

Dry expanded kibbles with ingredients that bring extra nutrition and health benefits are much better received than those which are simply an economic choice by manufacturers. Microbially enhanced protein (MEP) from soybeans, a fermented ingredient, may promote utilization. The objective of this study was to determine the influence of increasing lev...

Soluble fiber can be fermented by microflora in the colon resulting in short-chain fatty acid (SCFA) production. SCFA can be used as an energy source for the host, enterocytes, colonocytes, and immune cells, supporting cell differentiation and gut health. An in vitro model has been used to predict the colonic fermentability of fibers. Whole soybean...

Co-products from the ethanol industry may be able to provide high-quality sustainable protein sources for pet foods. Unlike traditional co-products, corn fermented protein (CFP) contains a yeast component which may provide additional benefits. The objective of this study was to determine, by exchange, the effects of the yeast in corn fermented prot...

Significant improvement in thiamin retention of canned cat food has not been achieved by altering processing conditions. Some ingredients, such as yeasts, may supply thiamin able to withstand thermal processing. Therefore, the study objective was to evaluate yeast ingredients as thiamin sources for canned cat food. Six yeast ingredients were screen...

In companion animal nutrition, probiotics (direct-fed microbials) are marketed as functional ingredients that add value to pet foods due to the impact they have on gastrointestinal and immune health of dogs and cats. The nature of the beneficial effect each probiotic strain exerts depends on its metabolic properties and perhaps most importantly, th...

Treats are offered to dogs to reinforce the animal-owner bond and as rewards. Wheat, which contains gluten (gliadin and glutenin proteins), is often used in treats. The US is a leading producer of sorghum which might be an alternative; however, it does not have functional properties to form viscoelastic doughs, because is mainly composed of kafirin...

Background and Objectives Cross‐contamination of foodborne pathogens from equipment to food is a food safety concern. The objective of this study was to quantify the amount of Escherichia coli contamination in mill equipment after milling inoculated and noninoculated wheat in single milling run. Findings Mill equipment used for milling inoculated...

Background and Objectives Cross‐contamination of pathogens is a common cause of food recalls. The objectives of this study were to quantify the amount of Escherichia coli transferred during wheat milling and to model the E. coli concentration in wheat flour fractions during milling. Findings Higher ( p ≤ .05) E. coli counts were recovered in the n...

In companion animal nutrition, probiotics (direct-fed microbials) are considered functional ingredients that benefit the gastrointestinal and immune health of the host. Bacillus coagulans GBI-30, 6086 is a spore-forming bacterial strain that has been reported to survive environmental stresses, heat processing, and extreme-pH conditions. Extrusion c...

In previous research, super-fortification with copper decreased vitamin E content and darkened canned pet food, which prevented the analysis of black blemishes reported in commercial products. The pet food industry has linked these blemishes, which may be concerning to pet owners, to copper supplementation. The objective of this study was to determ...

This study evaluated the effects of antimicrobial acidulant addition on lipid oxidation of rendered chicken fat. Chicken fat was untreated (control) or treated with either sodium bisulfate (SBS) or lactic acid (LA) at 0.5% w/w and incubated for 6 weeks at 40°C. Peroxide value (PV), p-anisidine value (AV) and free fatty acid (FFA) levels were measur...

Salmonella subs. serovar enteritidis is a potential biological pathogen of concern in the poultry industry. Contamination of the bacterium on eggshells has led to human illnesses. With the implementation of new regulations, animal feed manufacturing continues to be under more stringent requirements. Specifically, there is zero tolerance for Salmone...

Fish oil inclusion into a dry pet food provides a source of long-chain omega-3 fatty acids. Polyunsaturated fatty acids in fish oil have antibacterial activity against various foodborne pathogens, such as Salmonella and pathogenic Escherichia coli. The purpose of this study was to determine the effect of temperature applied to dry pet food kibbles...

The objective of this study was to assess whether diets with increased resistant starch (RS) had a positive effect on markers of colonic health in dogs. Three identical diets were extruded with high, medium and low shear (HS, MS and LS) to incrementally increase RS, and fed to 24 dogs in a replicated 3 × 3 William’s Latin square design for 28-day p...

Pet food represents a large share of the U.S. economy, and the majority of it is produced through extrusion. Starches comprise between 30-60% of extruded dog foods and sources include cereals, tubers, legumes, and co-products from the human food chain. Starches are well digested and metabolized by dogs, with variations according to food processing...

The objective of this work was to modify extrusion parameters to yield greater resistant starch (RS) in a kibble and create a model to predict its concentration. A dog food was extruded through a small-scale twin-screw extruder as a central composite design with 6 central points (replicates) and 14 single replicates. There were three factors tested...

The objective of the present work was to produce dog foods from a single recipe at three levels of resistant starch (RS). The low (LS), medium (MS), and high shear (HS) foods were produced on a single-screw extruder at target screw speeds of 250, 375 and 460 rpm, respectively, and with increasing in-barrel moisture as shear decreased. Post-producti...

Hydrocolloids are commonly used in canned pet food. However, their functional effects have not been quantified in this food format. The objective was to determine the effects of select hydrocolloids on batter consistency, heat penetration, and texture of canned pet food. Treatments were added to the formula as 1% dextrose (D) and 0.5% guar gum with...

Yeast products have found much favor within companion animal nutrition. A recently developed proprietary process has introduced an enhanced yeast biomass from Candida utilis (merchandised as SylPro®) into the animal food marketplace. Candida utilis has been shown to be a valuable protein in canine, swine and aquaculture diets; however, no previous...

Yeast and distillers’ grains from ethanol products have been included in pet food for many years. However, their combination has not been evaluated in pet food. Grain distillers dried yeast (GDDY) is a combination of fermented grains which is rich in yeast. The objectives of this study were to determine the effects of increasing levels of GDDY on a...

Despite numerous process modifications, thiamine retention of canned cat food has not improved. Yeasts possess a binding protein which may provide a thiamine form able to withstand retort processing. Therefore, the objective was to evaluate dried yeasts as thiamine sources in canned cat food. Treatments were arranged as a 2ｘ4 factorial with 2 level...

Increasing the amount of liquid fat in the ration during extrusion can negatively affect product density and product expansion. High-fat ingredients, such as whole soybeans (WSB), may increase energy density while avoiding production issues. In a preliminary extrusion project, the addition of graded levels of WSB on food processing was evaluated. T...

This study aimed to evaluate the effect of Bacillus coagulans GBI-30, 6086 on the fecal microbiome of healthy adult dogs. Extruded diets containing graded levels of probiotic applied either to the base ration before extrusion or as a topical coating post-extrusion were randomly assigned to ten individually-housed Beagle dogs (7 castrated males, 3 s...

Increasing the amount of liquid fat to the ration during extrusion can negatively affect product density and product expansion. Ingredients, like whole soybeans (WSB), which are high in fat may aid increased energy density while avoiding production issues. In a preliminary extrusion project, the effects on the process of foods were evaluated, follo...

Traditionally, yeast products have been added to companion animal diets to improve palatability. Grain distillers dried yeast (GDDY), a coproduct from ethanol production which contains yeast, may be a viable option in pet food. The objective of this study was to determine the effects of increasing levels of GDDY in cat diets compared to soybean mea...

In a previous experiment, inclusion of guar gum, kappa carrageenan, locust bean gum, and xanthan gum were observed to influence the texture of wet pet food. However, limited published research has addressed their texture and water holding. Therefore, the objective was to quantify the differences in texture and expressible moisture (EM) due to commo...

Discolored thermally processed canned pet foods may be perceived by pet owners as moldy or adulterated. Interactions between trace minerals, especially copper, and fatty acids or carbohydrates may occur during canning. Today, copper is supplemented primarily as highly reactive, inorganically bound copper sulfate. Chelated copper sources may protect...

While fiber is not an indispensable nutrient for monogastric animals, it has benefits such as promoting gastrointestinal motility and production of short chain fatty acids through fermentation. Miscanthus x giganteus is a hybrid grass used as an ornamental plant, biomass for energy production, construction material, and as a cellulose source for pa...

The occurrence of recalls involving pathogenic Escherichia coli-contaminated wheat flours show the need for incorporating antimicrobial interventions in wheat milling. The objectives of this study were to assess the efficacy of sodium bisulfate (SBS) tempering in reducing E. coli O121 (ATCC 2219) and O26 (ATCC 2196) wheat load and to evaluate the i...

The role of dogs and cats in the society has changed much over the past 50 years. They have migrated from the barn to the backyard and now into the house. As a result, our relationship has changed how we care and feed them. With that we have expanded our knowledge regarding their nutritional needs and idiosyncrasies as well as introduced a wide arr...

Corn is one of the largest cereal crops worldwide and plays an important role in the U.S. economy. The pet food market is growing every year, and although corn is well utilized by dogs, some marketing claims have attributed a negative image to this cereal. Thus, the objective of this work was to review the literature regarding corn and its co-produ...

This study aimed to evaluate the inclusion of different protein binders and sorghum crisps in cereal bars for dogs and their effect on sensory properties, product texture, and dog preference. Fifteen cereal bars were developed in which three crisp sources (rice crisp, white and red sorghum crisp) and five sources of binders (corn syrup, spray dried...

Bacillus coagulans GBI-30, 6086 is a commercially available spore-forming non-toxigenic microorganism approved for use in dog foods with high resiliency to stresses associated with commercial manufacturing. The objectives of this research were to examine the effect of Bacillus coagulans on stool quality, nutrient digestibility, and intestinal healt...

Sustainability has become a watchword for a wide array of resource-intensive goods and services. This is promulgated by an increasing global population and concerns that natural resources and a hospitable climate will not be preserved for future generations. Life-cycle analysis is a tool that provides a framework to determine the magnitude products...

Beet pulp (BP) and cellulose (CE) are fibrous ingredients commonly used by pet food companies to produce diets targeting weight management and gut health. Miscanthus grass (MG) is a novel fibrous ingredient that might affect food manufacturing in a similar manner to CE. The objective was to determine the effects of these three fiber sources on extr...

Two experiments were conducted to evaluate the effects of dietary amino acid density and exogenous protease inclusion on growth performance and amino acid digestibility in poultry. In experiment 1, Cobb 500 broiler chicks (n = 480) were fed to 21 d of age. Treatments were arranged as a 2 × 4 factorial design with main effects of commercial protease...

Resistant starches comprise the starch fraction that escapes small intestine (SI) digestion and reaches the colon, where it is fermented by saccharolytic bacteria that produce beneficial postbiotics. Moreover, slowly digestible starches lower glycemic index and may promote satiety. The objectives of this study were to assess whether diets having in...

Many wet pet foods include carbohydrate ingredients that enhance viscosity for container filling or provide structure after processing. These gums and gels can cause differences in commercial sterilization as well as visible changes in product quality. Therefore, the objective was to determine the effect of different gums and gelling carbohydrates...

Previous work has evaluated fermentation of fiber ingredients; however, the effect of extrusion has rarely been explored. The objective was to determine post-extrusion fiber fermentability with a dog fecal in vitro model. Dietary treatments containing 10% apple pomace (AP), blueberry pomace (BP), or miscanthus grass (MM) were compared to a control...

Treats are food products given to dogs to strengthen bonds between owners and pets. Most treats on the market are made of wheat, mostly because of gluten binding properties. While sorghum lacks gluten, soluble animal proteins could be used as binders instead. The objective of this study was to evaluate appearance, aroma, flavor, texture/mouthfeel,...

Functional pet foods, such as those containing probiotics, are considered a key growth driver in the $37 billion market of dog and cat foods in the United States. Of particular interest to pet food applications is the patented bacterial strain Bacillus coagulans (GBI-30, 6086), a commercially available spore-forming non-toxigenic microorganism with...

Cellulose and beet pulp have been commonly used in the pet food industry to increase dietary fiber content of cat foods. However, pet food companies seek alternatives to these so-called byproducts. Miscanthus grass is grown for its fiber content and may serve as an alternative to traditional fibrous ingredients. The objectives of this study were to...

The differences in the recovery of Salmonella from rendered chicken fat treated with sodium bisulfate (SBS) when inoculated with a dry versus wet inoculum were evaluated. Food-grade rendered chicken fat was inoculated with a dry inoculum and a wet inoculum containing a cocktail of Salmonella serovars (Enteritidis, Heidelberg, and Typhimurium). In a...