FOOD-DEPRIVATION INCREASES THE RATS PREFERENCE FOR A FATTY FLAVOR OVER A SWEET TASTE

Previous research indicates that food deprivation increases the rat's preference for high-fat over low-fat foods. Since these foods differ i n their flavors and post-ingestive effects, both factors may be implic ated. The present study investigated preferences in food deprived and non-deprived rats using non-nutritive mineral oil emulsion (MO) and sa ccharin solution (SAG), which have a fatty flavor and sweet taste, res pectively. The deprived rats consumed more MO than SAC in one- and two -bottle tests, while the non-deprived rats ingested as much SAC as MO in one-bottle tests and preferred SAC in two-bottle tests. Several asp ects of the data suggest that the deprivation-related shift in prefere nce between MO and SAC was determined by changes in long-term energy b alance. A follow-up conditioning experiment discarded the possibility that the observed preference shift was related to differential reinfor cing effects of the two substances. in conclusion, long-term food rest riction increases the preference for an oily flavor over a sweet taste via a mechanism that does not involve nutritive feedback. It remains to be determined to what extent this alteration in flavor preference i nfluences food selection when post-ingestive nutritive feedback can in fluence food choice.