Longitudinal assessment of taurine and amino acid concentrations in dogs fed a green lentil diet

A recent association between the inclusion of pulses in canine diets and taurine deficiency has become a prevalent issue in the pet food industry. Although there is not a nutritional requirement for taurine by dogs, the appearance of taurine deficiencies has been related with more serious health issues, such as dilated cardiomyopathy. The objective of this study was to determine the circulating concentrations of plasma and whole blood taurine, indispensable and dispensable amino acid concentrations in the plasma, and taurine and creatinine concentrations in the urine of adult dogs fed a green lentil diet. Twelve, adult, female beagles were randomly assigned to a diet containing 45% green lentils (GLD) or a poultry byproduct meal diet (CON) for 90 days. Fresh urine samples were collected every 30 d and analyzed for taurine and creatinine concentrations. A blood sample also was collected every 30 d and analyzed for amino acids including taurine. Animal procedures were approved by the University of Illinois Institutional Animal Care and Use Committee. All diets were formulated to meet or exceed the nutrient requirements outlined by AAFCO (2018) and all dogs remained healthy throughout the study. The concentrations of taurine in the plasma and whole blood showed no differences (P > 0.05) between dietary treatments or across time points. Similarly, no differences (P > 0.05) in plasma methionine concentrations were observed between treatments or across time points. A treatment effect (P < 0.05) showed dogs fed GLD had higher total primary fecal bile acid (BA) excretion compared with dogs fed CON. The differential abundance of fecal microbial communities showed Firmicutes as the predominant phyla in dogs fed both GLD and CON, with Bacteroidaceae, Erysipelotrichaceae, and Lactobacillaecae as predominant families in dogs fed GLD. The α-diversity of dogs fed GLD ( P < 0.05) was lower than in dogs fed CON. These data suggest that the inclusion of 45% green lentil in extruded diets does not lower whole blood and plasma taurine concentrations during a 90 d period and is appropriate for use in a complete and balanced formulation for dogs.

Brewing with 10% and 20% Malted Lentils—Trials on Laboratory and Pilot Scales

Lentils, a popular foodstuff worldwide, are gaining more interest for their use in alternative diets. In addition, we are observing an ever-growing demand for new raw materials in the malting and brewing industry and an overall rising interest in a low-gluten lifestyle. Therefore, in this study, malt was produced from green lentils and used in both laboratory- and pilot-scale brewing trials. Malted lentils were used as 10% and 20% adjuncts at the laboratory scale, following the Congress mash procedure, and the most important parameters (e.g., filtration time, pH, color, extract, fermentability) of the wort and beer samples were analyzed with a special focus on the concentrations of metal ions (Mg2+, Ca2+, Zn2+, Fe) in wort. The production of beer with lentil malt as an adjunct was then scaled up to 1 hl, and several beer parameters were analyzed, including the gluten content and foam stability. The results showed that the gluten content was decreased by circa 35% and foam stability was enhanced by approximately 6% when adding 20% lentil malt. Furthermore, the use of lentil malt reduced the filtration time by up to 17%. A trained panel evaluated the sensorial qualities of the produced beers. Overall, the use of green lentil malt shows promising results for its potential use in brewing.

119 Awardee Talk: A Matter of the Heart: The Use of Pulses in Canine and Feline Nutrition

In the pet food industry, the popularity of plant-based protein sources has risen as consumer demand for grain-free and novel protein sources increase. However, minimal research has been conducted as regards use of pulses and their effects on acceptability and digestibility in canine and feline nutrition. In addition, market shift towards grain-free and pulse-rich diets has presented concerns about the suitability of pulses as viable protein sources. In July 2018, the FDA published a press release discussing a potential link between diets containing legumes and the development of dilated cardiomyopathy (DCM) in dogs. As such, part of our research program has focused on the 1) characterization of the macronutrient composition and protein quality of plant-based protein sources, 2) evaluation of the effects of plant-based protein sources in extruded canine and feline diets on macronutrient digestibility, and modulation of fecal microbiota and metabolites, and 3) determination of the longitudinal effects of high pulse inclusion in diets on taurine status in dogs. Pulse ingredients contained approximately 20% crude protein, and had methionine or tryptophan as the first-limiting amino acids using the precision-fed cecectomized rooster assay. When incorporated in canine and feline diets, pulses did not result in negative effects on macronutrient digestibility or fecal scores. However, shifts in fecal microbial and metabolites were observed in animals fed pulse-based in contrast with animal-based protein diets. The inclusion of 45% green lentils in extruded diets did not cause decreased plasma or whole blood taurine or methionine levels. Additionally, excess taurine was not depleted from these animals in the urine or feces. Taurine status was considered normal in these dogs, despite changes in fecal bile acid concentrations and microbiota. Although we are currently carrying out further research projects investigating potential association of pulse rich diets and canine DCM. Current research findings from our laboratory suggest the inclusion of pulses may not be the causative factor. The use of plant-based proteins as ingredients in canine and feline diets not only meet consumer demand but also provide a valuable, safe, and nutritionally adequate alternative to traditional protein sources.

Glycemic response in nonracing sled dogs fed single starch ingredients and commercial extruded dog foods with different carbohydrate sources

This study adapted the established glycemic index (GI) methodology used in human research to perform two studies in sled dogs in order to assess the blood glucose-raising potential of pulse-based dog foods. The first was a pilot study (n = 6 dogs) to determine the GI of single starch sources (white bread, cooked white rice, and cooked green lentils) using a glucose solution as control. Next, the effect on glycemic and insulinemic meal responses and GI of commercial extruded dog foods containing different categories of starch sources (traditional grain, whole grain, grain-free, and vegan) were investigated on 11 dogs using a glucose control. Results were compared using repeated measures analysis of variance (ANOVA). Consumption of 10 g of available carbohydrate (Av CHO) was insufficient to elicit a measurable response in blood glucose for GI determination, and as such, the amount was increased to 25 g for the second study. The GI (±SE) of the single starch sources and dog foods was: white bread: 47 ± 11, cooked white rice: 71 ± 14, cooked green lentils: 60 ± 20 (P = 0.569), traditional grain: 83 ± 17, whole grain: 56 ± 8, grain-free: 41 ± 6, and vegan: 65 ± 15 (P = 0.154). No statistical differences in glycemic response over time were observed between the single starch sources or the extruded diets tested (P = 0.1412; P = 0.2651). The insulinemic response elicited by the extruded diets was also not different (P = 0.079); however, the traditional grain diet did have the slowest time to peak for insulin (P = 0.0078). Among single starch sources and extruded dog foods, there were no differences in the glycemic indices measured in this study. The GI methodology has not been validated for use in canine species, and it is likely that our results were due to higher interindividual variation or inadequate study power. Regardless, this study will serve to better define future studies to investigate the potential physiological benefits of low GI foods for dogs.

PSIII-20 Use of legumes and yeast as main protein sources in extruded canine diets

Plant-based protein sources have gained popularity as consumer demand for grain-free and novel protein sources increase. However, minimal information is available about the effects on digestibility, gastrointestinal tolerance, and fermentative end-products of novel plant-based proteins in dogs. Therefore, the objective of this study was to evaluate legumes and yeast as protein sources in extruded canine diets. Five diets were formulated to be isocaloric and isonitrogenous with either garbanzo beans (GB), green lentils (GL), peanut flour (PF), dried yeast (DY), or poultry byproduct meal (CON) as the primary protein source. Ten, adult, female beagles (mean age: 5.0 ± 1.2 years, mean BW: 11.9 ± 1.3 kg) were used in a replicated 5x5 Latin square design. Each 14 d period consisted of a 10 d diet adaptation followed by a 4 d total fecal and urine collection. At the end of each period, 5 mL of blood was collected and analyzed for a complete blood count and serum chemistry. Serum metabolites were within normal ranges and all dogs remained healthy throughout the study. Fecal scores, evaluated on a 5-point scale, were considered ideal and did not differ among treatments. Apparent total tract digestibility (ATTD) of dry matter and organic matter was highest (P < 0.05) for CON (86.3% and 91.2%, respectively) and PF (85.6% and 90.3%, respectively) and lowest (P < 0.05) in dogs fed the DY diet (80.1% and 84.3%, respectively). GL had the lowest (P < 0.05) crude protein ATTD (81.5%) with no differences among other treatments (84.6% average). Dogs fed CON, PF, and GB diets had the highest (P < 0.05) acid hydrolyzed fat ATTD, with an average of about 94%. In conclusion, novel plant-based protein sources and yeast are comparable to traditional poultry byproduct meal diet and are appropriate protein sources for canine diets.

Bioprocessing of common pulses changed seed microstructures, and improved dipeptidyl peptidase-IV and α-glucosidase inhibitory activities

Type 2 diabetes mellitus (T2DM) is a leading cause of death globally. T2DM patients experience glucose intolerance, and inhibitors of dipeptidyl peptidase IV (DPP-IV) and α-glucosidase are used as drugs for T2DM management. DPP-IV and α-glucosidase inhibitors are also naturally contained in foods, but their potency can be affected by the food matrix and processing methods. In this study, germination and solid-state fermentation (SSF) were used to alter pulse seed microstructures, to convert compounds into more bioactive forms, and to improve their bioaccessibility. Germination substantially modified the seed microstructure, protein digestibility, contents and profiles of phenolic compounds in all the pulses. It also increased DPP-IV and α-glucosidase inhibitory activities in chickpeas, faba beans and yellow peas. Compared to germination, SSF with Lactobacillus plantarum changed the content and the profile of phenolic compounds mainly in yellow peas and green lentils because of greater disruption of the seed cell wall. In the same pulses, heat treatment and SSF of flour increased DPP-IV and α-glucosidase inhibitory activities. The results of this study suggest that germination and SSF with L. plantarum are effective and simple methods for modulating phenolic and protein profiles of common pulses and improve the action on DPP-IV and α-glucosidase.

Nutritional Composition and Bioactive Content of Legumes: Characterization of Pulses Frequently Consumed in France and Effect of the Cooking Method

Pulses display nutritional benefits and are recommended in sustainable diets. Indeed, they are rich in proteins and fibers, and can contain variable amounts of micronutrients. However, pulses also contain bioactive compounds such as phytates, saponins, or polyphenols/tannins that can exhibit ambivalent nutritional properties depending on their amount in the diet. We characterized the nutritional composition and bioactive compound content of five types of prepared pulses frequently consumed in France (kidney beans, white beans, chickpeas, brown and green lentils, flageolets), and specifically compared the effects of household cooking vs. canning on the composition of pulses that can be consumed one way or the other. The contents in macro-, micronutrients, and bioactive compounds highly varied from one pulse to another (i.e., 6.9 to 9.7 g/100 g of cooked product for proteins, 4.6 to 818.9 µg/100 g for lutein or 15.0 to 284.3 mg/100 g for polyphenols). The preparation method was a key factor governing pulse final nutritional composition in hydrophilic compounds, depending on pulse species. Canning led to a greater decrease in proteins, total dietary fibers, magnesium or phytate contents compared to household cooking (i.e., −30%, −44%, −33% and −38%, p < 0.05, respectively, in kidney beans). As canned pulses are easy to use for consumers, additional research is needed to improve their transformation process to further optimize their nutritional quality.