Evaluation of graded levels of corn-fermented protein on stool quality, apparent nutrient digestibility, and palatability in healthy adult cats.

Dried distillers' grains, coproducts 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 with traditional dried distillers' grains, increasing its appeal for inclusion into pet food. Therefore, the objectives of this study were to determine the effects of increasing levels of CFP on stool quality, apparent total tract digestibility (ATTD), and palatability in adult cats. Four extruded diets were fed to 11 adult cats in an incomplete 4 × 4 replicated Latin square design. The control diet contained 15% soybean meal (0C) and CFP was exchanged for soybean meal at either 5%, 10%, or 15% (5C, 10C, 15C). Cats were fed each dietary treatment for 9-d adaption followed by 5-d total fecal collection. Feces were scored on a 1 to 5 scale, with 1 representing liquid diarrhea and 5 representing hard pellet-like (Carciofi et al., 2008). A fecal score of 3.5 to 4 was considered ideal. Titanium dioxide was added to all diets (0.4%) as a marker to estimate digestibility. Data were analyzed using a mixed model in SAS (version 9.4, SAS Institute, Inc., Cary, NC) with treatment as a fixed effect and cat and period as random effects. Fecal dry matter percent and dry fecal output were greater (P < 0.05) at elevated levels of CFP. Stool scores were maintained (P > 0.05) throughout treatments (average; 4). Dry matter, organic matter, crude protein, and gross energy ATTD decreased when cats were fed 15C. There was no difference in ATTD of fat or total dietary fiber among treatments. For palatability assessment, cats preferred 5C over 0C but had no preference with increased CFP inclusion. These results suggest that CFP is comparable to SBM, but there may be a maximum inclusion level of 10% when fed to cats.

Sustainable ingredients are of increasing demand within the pet food industry. Corn-fermented protein (CFP) could provide a sustainable protein source for pet food. CFP is a coproduct from ethanol production, which is produced using post-fermentation separation technology to create a high-protein, low-fiber ingredient. In this work, 11 healthy cats were fed diets containing 0%, 5%, 10%, and 15% CFP in exchange for soybean meal. Cats were fed each dietary treatment for 14 d with a 9-d adaptation phase followed by a 5-d total fecal collection. Stool quality and diet digestibility were analyzed. Total fecal output of cats increased, and diet digestibility decreased with the 15% CFP inclusion. These results are likely due to the fiber component of CFP indicating a maximum inclusion level at 10% when fed to cats. In addition, palatability of diets was evaluated at a commercial kennel and proved to be acceptable at all CFP inclusion levels when fed to cats. Further research is needed to evaluate the possible impact of CFP on animal health when included in pet food.

Sensory attributes, dog preference ranking, and oxidation rate evaluation of sorghum-based baked treats supplemented with soluble animal proteins.

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 United States is a leading producer of sorghum which might be an alternative; however, it does not have functional properties to form viscoelastic doughs, because it is mainly composed of kafirin protein. Therefore, the objectives of this study were to determine the effects of supplementing soluble animal proteins in whole sorghum rotary-molded baked dog treats on dog preference, sensory attributes, and oxidation rate. The treats were produced in triplicate in a 2 x 4 + 1 augmented factorial arrangement of treatments. Two whole sorghum flours (WWS and WRS), four protein sources [none (NC), spray-dried plasma (SDP), egg protein (EP), and gelatin (GL)], and a positive control with wheat (WWF-GTN) were evaluated. A preference ranking test with twelve dogs was performed. Additionally, five trained panelists scored the intensity of appearance, aroma, flavor, texture/mouthfeel, and aftertaste attributes. Finally, the treats were stored at 30 °C and 60% RH, and hexanal concentrations were measured on days 0, 28, 56, and 112. The data was analyzed using the statistical software SAS for the animal and oxidation rate evaluations with significance considered at P<0.05. The descriptive sensory evaluation data was analyzed using multivariate analysis (XLSTAT). The dogs did not detect differences among WWF-GTN, WWS, or WRS treats when evaluated together. However, the WWF-GTN, WWS-SDP, and WWS-EP treatments were preferred among the white sorghum treatments. The EP treatments led to some consumption difficulties by dogs because of their hard texture. The panelists reported a high degree of variation in the appearance and texture across treatments. The WRS and WWS treats with SDP or EP were darker, while NC treats had more surface cracks. Initial crispness, hardness, and fracturability were higher in EP treatments compared to all other sorghum treatments. The predominant flavor and aftertaste identified were "grainy." The hexanal values for all treats were <1.0 mg/kg except for the EP treatments that had higher values (2.0-19.3 mg/kg) across the shelf-life test. This work indicated that the replacement of WWF-GTN by WWS and WRS, along with soluble animal proteins like SDP or GL would produce comparable preference by dogs, oxidation rates, product aromatics, flavor, aftertaste attributes, and, at a lower degree, product texture.

Treats are commonly given to dogs to create a better relationship with the owner. Most treats on the market are baked and wheat based as this grain has gluten that provides good texture attributes and facilitates production. Other grains such are sorghum are widely produced in the United States. However, baking treats with alternative grains is challenging as they lack the same functional proteins. The objectives of this study were to determine the effects of soluble animal proteins in whole sorghum rotary-molded dog treats on dog preference, sensory attributes, and oxidation markers, such as hexanal. Two whole sorghum flours [white (WWS) and red (WRS)], four protein sources [none (NC), spray-dried plasma (SDP), egg protein (EP), and gelatin (GL)], and a positive control with wheat (WWF-GTN) were evaluated. The dogs did not detect differences between WWF-GTN, WWS, or WRS treats when evaluated together. However, the EP treatments, because of their hard texture, led to some consumption difficulties. The panelists reported a high variation in the appearance and texture across treatments. Additionally, the predominant flavor and aftertaste identified were "grainy." The hexanal values were not noticeable, except for the EP treatments that had higher concentrations across the duration of the evaluation.