EFFECTS OF TIME-RESTRICTED ACCESS TO PROTEIN AND OF ORAL-SENSORY CUESON PROTEIN SELECTION

The effects on protein consumption of restricting access to protein an d of varying the oral-sensory properties of protein diets were measure d. During the initial phase of the study, rats were maintained on a se lf-selection diet in which three different macronutrient sources (carb ohydrate, fat, and either soy-based or casein-based protein diets) wer e continuously available. For the remaining 9 days of the study, half of the rats were protein deprived for 23 h each day and the other half continued to receive the same protein diet during this 23-h period. T he remaining 1 h of each day was a test period in which all rats had a ccess to a protein diet that was either the same as or different from the one they had received in the initial phase. Compared to the nonres tricted rats, the protein-restricted rats consumed more than twice as much of the available protein diet during 1-h test periods. For the no nrestricted rats, those that received a different protein diet during the 1-h test periods consumed 60% more of the protein diet than did th ose that received the same protein diet. These results indicate that i ncreases in protein consumption following protein deprivation can be a ttributed, at least in part, to the oral-sensory properties of diets a nd not necessarily to a specific protein appetite.