The present study carried out with individuals submitted, for an average time of 8 years, to bariatric and metabolic surgery, showed that all the offered formulations, containing whey protein supplement had satisfactory and higher acceptance than the average value. All the formulations used had a high protein value, prioritizing the use of fresh and minimally processed foods (snacks and meals). The sensorial analysis revealed the acceptance over 78% of all formulations.
Despite the absence of other similar experimental studies for comparison, these findings are in line with other publications that show the importance of strategies to reach the daily protein goal, through a high-protein diet, supplementation, as well as the elaboration of recipes adapted to individuals submitted to bariatric surgery proposed in this work. 14,15
Whey protein supplementation after bariatric surgery has a beneficial effect enhancing the loss of body fat tissue and reducing the loss of lean body mass.7 It is common that the surgery leads to the individual’s difficulty in consuming foods rich in fibrous protein foods, such as beef and fish. To meet the high protein needs, it is suggested to increase the intake of other less fibrous dietary sources with high biological value and to perform different cooking processes. 2,14
According to Cambi et al., the whey protein supplement intake should be encouraged in liquid formulations, as observed in clinical practice, however through this study it was possible to test different ways of using this supplement in recipes for greater adherence in the long term. 16,17
Regarding the difficulty in consuming the protein supplement in the late postoperative period, to achieve protein goals, several authors mention the change in taste and texture after adding the supplement in the formulation, as well as some reports of intestinal discomfort and high cost, as also observed. in this study. 7–9,18
Based on the results of the chemical analysis, the recipes presented in this study contained an average of 12.71 grams of protein per serving. Considering the recommendations to prevent sarcopenia, the intake of 25 to 30 grams of protein per meal, distributed in three main meals, a portion of the formulations presented in this paper already contributes approximately 51% of the lower recommended value. When considering the recommended guidelines for bariatric and metabolic surgery, a minimum of five meals and 60 grams of protein per day, in one meal the ideal would be the consumption of at least 12 grams of protein, therefore a portion of these formulations provides an approximate contribution of 100% of the recommendations.1,2,19
Faria et al., refer that when selecting recipes for individuals undergoing bariatric surgery, a minimum amount of protein per recipe of 10 grams for snacks and 20 grams for main meals should be considered. Therefore, all recipes tested in this study exceed the guidance of these authors.20
In the sensorial analysis of recipes 6597 and 9539, the attributes color and flavor showed significant difference when separated by type of bariatric surgery and gender.
The data from the hedonic scale of formulation 6597 according to color, flavor and aroma criteria, and the type of surgery showed a preference in the acceptance of individuals undergoing the Roux-en-Y Gastric Bypass technique, when compared to those undergoing Vertical Gastrectomy. Literature data confirm that the anatomical and metabolic changes associated with RYGB show greater acceptance of salty formulations, due to a tendency to decrease the values of perception of sweet taste.21–23
Smith et al (2021) suggest that bariatric surgery highlights neurobiological reward mechanisms in taste preference, which may correct the brain responses to food stimuli, high in sucrose and fat in the circuits that mediate reward function. Those changes in taste preference may affect the food intake and weight reduction.22
The systematic review by Schoar and colleagues (2019) provided evidence confirming postoperative changes in sensitivity to four taste domains after different bariatric procedures. Patients with Vertical Gastrectomy showed increased sensitivity for four taste domains (sweet, sour, salty, and bitter). However, patients with RYGB had a variable pattern in taste perception, showing reduced sensitivity to sweet taste and increased sensitivity to salty and sour taste, confirming data from the literature.23
Both surgical procedures, RYGB and VG, promote modifications in the gastrointestinal tract, that result in dysbiosis, promoting differences in the composition of the salivary and fecal microbiota and bacteria-derived metabolites such as butyric acid and butyrate. Differences in the microbiota composition profile, including salivary microbiota between individuals with obesity and eutrophy are well documented; however, how these changes affect taste is not fully established.24
In the present study, 22 individuals rejected the taste of recipe 9539, and when separated by gender, different results were observed. The rejection of the sweet taste was considered by the average of the sensory analysis as less than five. The sweetener presents in this formulation associated with the supplement containing partially hydrolyzed proteins promotes a bitter taste.9,25 In males, there was an acceptance of 72.7%, while in females, 34.5%. In the males there was a preference for a sweet taste, and perhaps the presence of certain ingredients in the formulation may have influenced it, such as milk and cocoa. These ingredients contain tryptophan, its metabolites, such as serotonin, play a role in the metabolism and appetite observed in obesity 7, confirming data from several studies on taste modifications after surgery.19–24
Several studies have shown that most amino acids have flavor. Delompré et al., state that amino acids can contribute to the aftertaste, L-glutamine and L-proline have a sweet taste, L-leucine and L-arginine have a bitter taste.25 In the recipes containing protein supplement offered to individuals undergoing bariatric surgery, these four amino acids were contained. Therefore, the results of the sensory analysis may have been influenced by the presence of the amino acids contained in the whey protein supplement. To better understand this issue further studies with hyperproteic formulations without supplementation should be conducted.