| Title: | Protein hydrolysates are avoided by herbivores but not by omnivores in two-choice preference tests |
| Author(s): | Field KL; Bachmanov AA; Mennella JA; Beauchamp GK; Kimball BA; |
| Address: | "Monell Chemical Senses Center, Philadelphia, Pennsylvania, United States of America" |
| DOI: | 10.1371/journal.pone.0004126 |
| ISSN/ISBN: | 1932-6203 (Electronic) 1932-6203 (Linking) |
| Abstract: | "BACKGROUND: The negative sensory properties of casein hydrolysates (HC) often limit their usage in products intended for human consumption, despite HC being nutritious and having many functional benefits. Recent, but taxonomically limited, evidence suggests that other animals also avoid consuming HC when alternatives exist. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated ingestive responses of five herbivorous species (guinea pig, mountain beaver, gopher, vole, and rabbit) and five omnivorous species (rat, coyote, house mouse, white-footed mouse, and deer mouse; N = 16-18/species) using solid foods containing 20% HC in a series of two-choice preference tests that used a non-protein, cellulose-based alternative. Individuals were also tested with collagen hydrolysate (gelatin; GE) to determine whether it would induce similar ingestive responses to those induced by HC. Despite HC and GE having very different nutritional and sensory qualities, both hydrolysates produced similar preference score patterns. We found that the herbivores generally avoided the hydrolysates while the omnivores consumed them at similar levels to the cellulose diet or, more rarely, preferred them (HC by the white-footed mouse; GE by the rat). Follow-up preference tests pairing HC and the nutritionally equivalent intact casein (C) were performed on the three mouse species and the guinea pigs. For the mice, mean HC preference scores were lower in the HC v C compared to the HC v Cel tests, indicating that HC's sensory qualities negatively affected its consumption. However, responses were species-specific. For the guinea pigs, repeated exposure to HC or C (4.7-h sessions; N = 10) were found to increase subsequent HC preference scores in an HC v C preference test, which was interpreted in the light of conservative foraging strategies thought to typify herbivores. CONCLUSIONS/SIGNIFICANCE: This is the first empirical study of dietary niche-related taxonomic differences in ingestive responses to protein hydrolysates using multiple species under comparable conditions. Our results provide a basis for future work in sensory, physiological, and behavioral mechanisms of hydrolysate avoidance and on the potential use of hydrolysates for pest management" |
| Keywords: | Animals Caseins Cellulose Collagen Coyotes *Food Preferences Gelatin Rabbits Rodentia; |
| Notes: | "MedlineField, Kristin L Bachmanov, Alexander A Mennella, Julie A Beauchamp, Gary K Kimball, Bruce A eng R01DC00882/DC/NIDCD NIH HHS/ R01 DC000882/DC/NIDCD NIH HHS/ R01 HD037119-08/HD/NICHD NIH HHS/ R01 HD037119/HD/NICHD NIH HHS/ R01 HD37119/HD/NICHD NIH HHS/ T32 DC000014/DC/NIDCD NIH HHS/ R01 HD037119-07/HD/NICHD NIH HHS/ 2 T32 DC 00014/DC/NIDCD NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't 2009/01/06 PLoS One. 2009; 4(1):e4126. doi: 10.1371/journal.pone.0004126. Epub 2009 Jan 5" |
