Molecular-Sensory Decoding of the Citrus latifolia Aroma.

A modified aroma extract dilution approach (AEDA), followed by the determination of flavor dilution (FD) factors, a quantitative analysis and calculation of the relative flavor activity (RFA) and odor activity values (OAVs) as well as recombination experiments were conducted to evaluate the odor- and taste-relevant components of cold-pressed Citrus latifolia peel oil. A 2-fold concentration by distillation and reanalysis, compared with the original oil, revealed relevant components. Partition of the odor-active substances into four reconstitution groups according to their respective FD factors, followed by a recombination, allowed for a better understanding of the contribution of each FD-factor group to the overall aroma. Especially α-pinene, limonene, γ-terpinene, and 7-methoxycoumarin contribute significantly to the distinct aroma profile of C. latifolia. Heptadecanal (CAS 629-90-3) was described for the first time as an odor-active substance in an enriched C. latifolia peel oil. Campherenyl acetate (CAS 18530-07-9) was identified in nature for the first time and described with a herbal, minty and citrus-like odor. The odor profile of the final recombinant mixture, containing 36 components, was similar to cold-pressed C. latifolia peel oil for most descriptors, whereas the taste profile was described as more aldehydic and citral-like.

Sensory Impact of Novel Dihydrocoumarins in Native Lime Oils.

Citrus fruits have been known and valued for their aroma in food and perfume ever since humans have maintained written records. Often described as the "champagne" of citrus oils, especially cold pressed lime peel oils have raised attention. Particularly peel oils of Citrus latifolia exhibit a pleasant coumarinic, sweet, and balsamic aroma in comparison to its close relative, the Citrus aurantifolia. Those coumarinic notes have not been completely understood until today. Thus, this study aimed to identify the responsible substances and elucidate their contribution and impact on the aroma of cold-pressed lime oil. By combining distillation, fractionation, olfactory detection, and structure elucidation, the responsible key aroma components were identified. A combination of coumarins and their corresponding saturated analogs have been identified to significantly contribute to the typical coumarinic-like aroma, including three new flavor compounds that have not yet been described in the literature as lime oil constituents: 7-methoxy-2-chromanone (3,4-dihydro-7-methoxy-2H-1-benzopyran-2-one; CAS 20921-02-2), 5,7-dimethoxy-2-chromanone (3,4-dihydro-5,7-dimethoxy-2H-1-benzopyran-2-one; CAS 82243-01-4) and 5,6-dihydrobergaptene (5,6-dihydro-4-methoxy-7H-furo[3,2-g][1]benzopyran-7-one; CAS 29050-61-1). The sensorial evaluation of the impact of these components on the lime aroma profile has shown flavor-modulating effects and the ability to enhance aldehydic-peely, juicy, and fruity notes as well as their importance in reproducing the authentic, typical coumarin-like notes.

Impact of lactisole on the time-intensity profile of selected sweeteners in dependence of the binding site.

Currently, there is limited insight into the influence of the different binding sites of agonists and antagonists of the sweet taste receptor TAS1R2/TAS1R3 on temporal sensory properties of sweet tasting compounds. We investigated whether the binding site and a competitive or allosteric inhibition of TAS1R2/TAS1R3 influence the time-dependent sensory perception and in vitro TAS1R2/TAS1R3-activation profiles. We compared time-intensity ratings of cyclamate, NHDC, acesulfame K, and aspartame with and without lactisole with the corresponding TAS1R2/TAS1R3-activation in transfected HEK293 cells. In combination with lactisole, cyclamate and NHDC demonstrated a shift of the dose-response curve corresponding to a competitive inhibition by lactisole in the sensory and the cell experiments. Allosteric inhibition by lactisole for aspartame and acesulfame K was seen in the cell experiments, but not the sensory ratings. In conclusion, the data do not support a major impact of the binding site on the time-intensity profile of the tested sweeteners.

Dietary administration of ß-ionone epoxide to Sprague-Dawley rats for 90 days.

In a 90-day GLP-compliant study groups of Sprague-Dawley rats (10/sex/group) were fed diets containing ß-ionone epoxide, a fragrance material and a flavoring substance, at dietary concentrations providing target intakes of 0, 20, 40 and 80 mg/kg bw/day. There were no deaths and no adverse changes in clinical observations, ophthalmological examinations, body weight, body weight gain, food consumption, food efficiency; hematology, serum chemistry, urinalysis parameters; or in macroscopic findings attributable to ß-ionone epoxide administration. Increased absolute and relative liver weights in high dose females without correlating hepatic histopathological findings were considered non-adverse. Cortical vacuolation of adrenal zona fasciculata was observed in high-dose males but was considered non-adverse due to the nondegenerative nature of this alteration. ß-Ionone epoxide did not influence estrus cyclicity in females and did not affect sperm morphology or epididymal sperm count, homogenization-resistant spermatid count and motility measurements in male rats. The no-observed-adverse-effect level (NOAEL) for administration of ß-ionone epoxide in the diet was determined to be the highest dose tested of 80 mg/kg bw/day.

Sweetness Perception is not Involved in the Regulation of Blood Glucose after Oral Application of Sucrose and Glucose Solutions in Healthy Male Subjects.

SCOPE: This study investigates the effect of the sweetness of a sucrose versus an isocaloric glucose solution in dietary concentrations on blood glucose regulation by adjusting the sweetness level using the sweet taste inhibitor lactisole. METHODS AND RESULTS: A total of 27 healthy males participated in this randomized, crossover study with four treatments: 10% glucose, 10% sucrose, 10% sucrose + 60 ppm lactisole, and 10% glucose + 60 ppm lactisole. Plasma glucose, insulin, glucagon-like peptide 1, and glucagon levels are measured at baseline and 15, 30, 60, 90, and 120 min after beverage consumption. Test subjects rated the sucrose solution to be sweeter than the isocaloric glucose solution, whereas no difference in sweetness is reported after addition of lactisole to the sucrose solution. Administration of the less sweet glucose solution versus sucrose led to higher blood glucose levels after 30 min, as reflected by a lower ΔAUC for sucrose (1072 ± 136) than for glucose (1567 ± 231). Application of lactisole leads to no differences in glucose, insulin, or glucagon responses induced by sucrose or glucose. CONCLUSION: The results indicate that the structure of the carbohydrate has a stronger impact on the regulation of blood glucose levels than the perceived sweetness.

A chemical structure-based approach for estimating the added levels of flavourings to foods for the purpose of assessing consumer intake.

Intake assessment and hazard profile of chemical substances are the two critical inputs in a safety assessment. Human intake assessment presents challenges that stem either from the absence of data or from numerous sources of variability and uncertainty, which have led regulators to adopt conservative approaches that inevitably overestimate intake. Refinements of intake assessments produce more realistic estimates and help prioritise areas of concern and better direct investment of resources. However, use levels (ULs), which represent the usual added amount of flavourings to food products, are the starting point for refined intake assessments, are data-intensive, and data availability is often a limitation. The work presented here was undertaken to investigate the use level patterns of substances used as flavourings in foods and to develop a systematic tool for data extrapolation based on chemical structure. The available dataset consists of use levels reported through eight industry surveys and hence are representative of industry uses rather than regulatory limits, which are higher by design and not realistic. A systematic statistical analysis was undertaken to determine whether the industry-reported UL data can be used to estimate use levels of flavouring substances belonging to the same chemical group for which such data are not available. Predictive modelling approaches were explored to evaluate relationships in the data and utilised additional variables relevant to technological considerations, such as volatility losses upon heat treatment, and Tanimoto index-based pair-wise structural similarity scores to determine whether more granular similarity information can reduce the within-group variability. The analyses indicated that the use levels of flavouring substances can reasonably be estimated based on the available data using chemical group classifications stratified by food category. Source of uncertainty and limitations are discussed.

Sweet Taste Antagonist Lactisole Administered in Combination with Sucrose, But Not Glucose, Increases Energy Intake and Decreases Peripheral Serotonin in Male Subjects.

Knowledge regarding the involvement of sweetness perception on energy intake is scarce. Here, the impact of glucose and sucrose sweetness, beyond their caloric load, on subsequent food intake and biomarkers of satiation was evaluated by co-administration of the sweet taste receptor inhibitor lactisole. A total of 27 healthy, male subjects received solutions of either 10% glucose w/o 60 ppm lactisole or 10% sucrose w/o 60 ppm lactisole. Subsequent food intake from a standardized breakfast was evaluated 2 h after receiving the respective test solution. Changes in postprandial plasma concentrations of cholecystokinin, ghrelin, and serotonin were determined over a period of 120 min, as was the body temperature. Administration of lactisole to the sucrose solution increased the energy intake from the subsequent standardized breakfast by 12.9 ± 5.8% (p = 0.04), led to a decreased Δ AUC of the body core temperature by 46 ± 20% (p = 0.01), and time-dependently reduced Δ serotonin plasma concentrations (-16.9 ± 6.06 ng/mL vs. -0.56 ± 3.7 ng/mL after sucrose administration, p = 0.03). The present study shows that lactisole increases energy intake and decreases plasma serotonin concentrations as well as body core temperature induced by sucrose, but not glucose. This finding may be associated with the different binding affinities of sucrose and glucose to the sweet taste receptor.

Structure-dependent effects of sweet and sweet taste affecting compounds on their sensorial properties.

A reduction in sugar consumption is desirable from a health point of view. However, the sensory profiles of alternative sweet tasting compounds differ from sucrose regarding their temporal profile and undesired side tastes, reducing consumers' acceptance. The present study describes a sensory characterization of a variety of sweet and sweet taste affecting compounds followed by a comparison of similarity to sucrose and a multivariate regression analysis to investigate structural determinants and possible interactions for the temporal profile of the sweetness and side-tastes. The results of the present study suggest a pivotal role for the number of ketones, aromatic rings, double bonds and the M LogP in the temporal profile of sweet and sweet taste affecting compounds. Furthermore, interactions between aggregated physicochemical descriptors demonstrate the complexity of the sensory response, which should be considered in future models to predict a comprehensive sensory profile of sweet and sweet taste affecting compounds.

Investigations into the Natural Occurrence of 1-Phenylethyl Acetate (Styrallyl Acetate).

So far, the occurrence of the flavor constituent 1-phenylethyl acetate in a natural source has not been unambiguously confirmed. The present work provides the detailed identification of 1-phenylethyl acetate from clove (Syzygium aromaticum (L.) Merr. & L.M. Perry) buds. In addition, headspace solid-phase microextraction-gas chromatography/mass spectrometry (GC/MS) analysis revealed further occurrence of 1-phenylethyl acetate in cocoa pulp and grape hyacinth flowers. A total of 15.2 g of essential oil was recovered from 7.2 kg of clove buds by simultaneous distillation-extraction followed by vacuum distillation. The distillate obtained was fractionated by silica column chromatography, whereby a significant enrichment of 1-phenylethyl acetate was achieved. The fraction containing the target analyte was further purified by preparative high-performance liquid chromatography, resulting in a final purity of ∼93.0%, yielding a total of 1 to 2 mg of 1-phenylethyl acetate. Identification of the isolated compound was achieved by GC/MS, infrared spectroscopy, enantioselective GC, isotope ratio MS, and nuclear magnetic resonance spectroscopy. Enantioselective GC/MS analysis revealed an enantiomeric excess of 60% (1S)-(-)-1-phenylethyl acetate in the isolate. The δ13CV-PDB value of -32.5 ± 0.5‰ was in accordance with that of C3-plants and other constituents found in genuine clove extracts.

Bitter-Tasting Amino Acids l-Arginine and l-Isoleucine Differentially Regulate Proton Secretion via T2R1 Signaling in Human Parietal Cells in Culture.

This study aimed at identifying whether the bitter-tasting amino acids l-arginine (l-ARG) and l-isoleucine (l-ILE) differentially regulate mechanisms of gastric acid secretion in human parietal cells (HGT-1 cells) via activation of bitter taste sensing receptors (T2Rs). In a first set of experiments, involvement of T2Rs in l-ARG and l-ILE-modulated proton secretion was demonstrated by co-treatment of HGT-1 cells with T2R antagonists. Subsequent whole genome screenings by means of cDNA arrays revealed T2R1 as a prominent target for both amino acids. Next, the functional role of T2R1 was verified by means of a T2R1 CRISPR-Cas9 knock-out approach. Here, the effect of l-ARG on proton secretion decreased by 65.7 ± 21.9% and the effect of l-ILE increased by 93.2 ± 24.1% in HGT-1 T2R1 ko versus HGT-1 wt cells (p < 0.05). Overall, our results indicate differential effects of l-ARG and l-ILE on proton secretion in HGT-1 cells and our molecular docking studies predict distinct binding for these amino acids in the binding site of T2R1. Further studies will elucidate whether the mechanism of differential effects involves structure-specific ligand-biased signaling of T2R1 or additional cellular targets.

Dietary administration of ß-caryophyllene and its epoxide to Sprague-Dawley rats for 90 days.

Two independent 90-day GLP-compliant studies were conducted in Sprague-Dawley rats with ß-caryophyllene or ß-caryophyllene epoxide, two common flavoring and fragrance materials. Dietary concentrations of ß-caryophyllene were 3500; 7000; and 21,000 ppm for males and 3500; 14,000; and 56,000 ppm for females. Dietary concentrations of ß-caryophyllene epoxide were 1750; 10,500; and 21,000 ppm. There were no deaths or clinical toxicity attributable to either substance administration. Statistically significant, dose-dependent reductions in body weight, body weight gain, food consumption, and food efficiency at the highest dietary concentrations of ß-caryophyllene, but not of ß-caryophyllene epoxide, were attributed to palatability issues. Neither ß-caryophyllene nor ß-caryophyllene epoxide influenced estrus cyclicity or sperm parameters. Macroscopic and microscopic findings were primarily related to changes in the kidneys of male rats, consistent with α2u-globulin nephropathy, and in the liver of male and female rats, including hepatocyte hypertrophy at the middle and high intake levels. These changes correlated with increased absolute and relative organ weights. Since the kidney findings were a species- and sex-specific effect, the NOAEL in each study was based on hepatocyte hypertrophy at the two highest dietary concentrations and were determined to be 222 mg/kg bw/day for ß-caryophyllene and 109 mg/kg bw/day for ß-caryophyllene epoxide.

2,4-Decadienal does not induce genotoxic effects in in vivo micronucleus studies.

2,4-Decadienal (E,E-) occurs naturally in foods and is also used as a flavoring ingredient. In vivo micronucleus studies were used to evaluate the potential for 2,4-decadienal to cause genotoxic effects. Male Han Wistar rats were dosed either by intraperitoneal injection or by gavage in two independent studies. The animals (12/group) received 25, 50, or 100 mg/kg bw of 2,4-decadienal via intraperitoneal injection, or 350, 700, or 1400 mg/kg bw via gavage. Dose-dependent decreases in the percentages of peripheral blood reticulocytes were observed in both studies, indicating that the target tissue was exposed to toxic levels of 2,4-decadienal. No induction of micronuclei in the bone marrow polychromatic erythrocytes or the peripheral blood reticulocytes was observed in either study. These results, coupled with previous mutagenicity studies, support the overall conclusion that 2,4-decadienal does not present a concern for genotoxicity.

Wheat Protein Hydrolysate Fortified With l-Arginine Enhances Satiation Induced by the Capsaicinoid Nonivamide in Moderately Overweight Male Subjects.

SCOPE: Increasing the intake of satiety-enhancing food compounds represents a promising strategy for maintaining a healthy body weight. Recently, satiating effects for the capsaicinoid nonivamide have been demonstrated. As various proteins and amino acids have also been demonstrated to decrease energy intake, oral glucose tolerance test (oGTT)-based bolus interventions of 75 g glucose + 0.15 mg nonivamide (NV control) are tested with/without combination of a wheat protein hydrolysate (WPH: 2 g) and/or l-arginine (ARG: 3.2 g) for their satiating effects in 27 moderately overweight male subjects. METHODS AND RESULTS: Compared to NV control intervention, ARG and WPH + ARG treatment both reduce (p < 0.01) total calorie intake from a standardized breakfast by -5.9 ± 4.15% and -6.07 ± 4.38%, respectively. For the WPH + ARG intervention, increased mean plasma serotonin concentrations (AUC: 350 ± 218), quantitated by ELISA, and delayed gastric emptying, assessed by 13 C-Na-acetate breath test (-2.10 ± 0.51%, p < 0.05), are demonstrated compared to NV control. Correlation analysis between plasma serotonin and gastric emptying reveals a significant association after WPH ± ARG intervention (r = -0.396, p = 0.045). CONCLUSION: Combination of WPH and ARG enhances the satiating effect of nonivamide, providing opportunities to optimize satiating food formulations by low amounts of the individual food constituents.

Absence of adverse effects following the gavage administration of methyl propyl trisulfide to Sprague-Dawley rats for 90 days.

Methyl propyl trisulfide is a flavoring substance found in foods such as garlic and onions. At the request of the European Food Safety Authority (EFSA) for additional toxicological data on methyl propyl trisulfide, groups of Sprague-Dawley rats (10/sex/group) were gavaged with 0 (corn oil vehicle control), 0.5, 2, or 6 mg methyl propyl trisulfide/kg bw/day in a 90-day GLP-compliant study. No effects on clinical observations, hematology and clinical chemistry parameters, organ weights, or macroscopic and histopathological examinations were found attributable to ingestion of methyl propyl trisulfide. The oral no-observed-adverse-effect level (NOAEL) for rats of both sexes was the highest dose tested of 6 mg/kg bw/day.

Absence of renal adverse effects from ß-myrcene dietary administration in OECD guideline-compliant subchronic toxicity study.

ß-Myrcene is a flavoring substance that occurs naturally in a large variety of foods. At the request of the European Food Safety Authority (EFSA) for additional toxicological data on ß-myrcene, groups of Sprague Dawley rats (10/sex/group) were administered diets containing 0, 700, 2100, or 4200 ppm of ß-myrcene designed to provide nominal doses of 0, 50, 150, or 300 mg/kg bw/day in a 90-day GLP-compliant study. Based on body weights, feed consumption, and substance stability data, final estimated daily intakes of ß-myrcene were calculated to be 20.4, 58.8, and 115.2 mg/kg bw for males and 24.2, 70.0, and 135.9 mg/kg bw for females. No effects on clinical observations, hematology and clinical chemistry parameters, organ weights, or macroscopic and histopathological examinations were found attributable to ingestion of ß-myrcene. The oral no-observed-adverse-effect level (NOAEL) for rats of both sexes was the highest dose tested. Based on feed consumption and test substance stability in the diet, the NOAEL was calculated to be 115 and 136 mg/kg bw/day for males and females, respectively.

Absence of adverse effects following administration of piperine in the diet of Sprague-Dawley rats for 90 days.

Piperine (E,E-) is a naturally occurring pungent and spicy constituent of black pepperand is also used as an added flavoring ingredient to foods and beverages. Piperine has been determined safe under conditions of intended use as a flavoring substance by regulatory and scientific expert bodies. While concurring with the Joint FAO/WHO Expert Committee on Food Additives (JECFA) and Flavor and Extract Manufacturers Association (FEMA) Expert Panel on the safety of piperine, the European Food Safety Authority (EFSA) requested additional toxicological data. The results of a 90-day GLPcompliant dietary study, conducted in Sprague-Dawley rats at target doses of 0, 5, 15, or 50 mg/kg bw/day, to respond to this request are presented herein. No adverse effects were found attributable to ingestion of piperine. Statistically significant changes in food consumption, body weight gain, and plasma cholesterol levels were not considered adverse as discussed in this paper. Therefore, the oral no-observed-adverse-effect level (NOAEL) was determined to be the highest dose tested of 50 mg/kg bw/day. EFSA derived a lower NOAEL of 5 mg/kg bw/day based on increased plasma cholesterol levels which still affords an adequate margin of safety of over 48,000 and concluded that piperine is not of safety concern.

Identification of Bitter-Taste Intensity and Molecular Weight as Amino Acid Determinants for the Stimulating Mechanisms of Gastric Acid Secretion in Human Parietal Cells in Culture.

Secretion of gastric acid, aimed at preventing bacterial growth and aiding the digestion of foods in the stomach, is chiefly stimulated by dietary intake of protein and amino acids (AAs). However, AAs' key structural determinants responsible for their effects on mechanisms regulating gastric acid secretion (GAS) have not been identified yet. In this study, AAs have been tested in the parietal cell model HGT-1 on GAS and on mRNA expression of genes regulating GAS. AAs' taste intensities from 0 (not bitter at all) to 10 (very bitter) were assessed in a sensory study, in which ARG (l: 6.42 ± 0.41; d: 4.62 ± 0.59) and ILE (l: 4.21 ± 0.43; d: 2.28 ± 0.33) were identified as bitter-tasting candidates in both isomeric forms. Pearson correlation showed that GAS in HGT-1 cells is directly associated with the bitter taste quality ( r: -0.654) in combination with the molecular weight of l-AA ( r: -0.685).

Capsaicin and nonivamide similarly modulate outcome measures of mitochondrial energy metabolism in HepG2 and 3T3-L1 cells.

Capsaicin, the highly pungent principle of red pepper, has been demonstrated to have anti-obesity properties by affecting energy and lipid metabolism. Recent evidence from human intervention trials shows that also less pungent capsaicin analogs, like nonivamide, may help to reduce total body fat, although mechanistic data comparing the effects of capsaicin and nonivamide on outcome measures of energy metabolism are lacking. Here, the tissue-specific effects of capsaicin and nonivamide on parameters of mitochondrial energy metabolism in 3T3-L1 and HepG2 cells are investigated. Lipid accumulation was reduced to a similar extent after treatment with both test substances during the maturation of 3T3-L1 cells by up to 6.91% for capsaicin and up to 4.89% for nonivamide (p < 0.01) at a concentration of 0.1 µM or 1 µM, respectively. Energy-producing pathways, as indicated by the reduced mitochondrial oxygen consumption and reduced glucose and fatty acid uptake, were diminished after incubation with both capsaicinoids at a concentration of 100 µM. The results from HPLC analyses revealed a reduced cellular energy charge potential after a 4 h treatment with nonivamide. In HepG2 cells, similar effects were demonstrated: the glucose uptake was reduced by 18.7% and 25.8% (p < 0.05), after a 24 h incubation with 100 µM capsaicin and nonivamide, respectively. In addition, the fatty acid uptake and oxygen consumption were decreased and the energy charge potential was diminished. These findings provide evidence that concentrations of capsaicin and nonivamide between 0.1 and 100 µM modulate the mechanisms of cellular energy metabolism to a similar extent, independent of the investigated tissue.

Investigation on Key Molecules of Huanglongbing (HLB)-Induced Orange Juice Off-flavor.

Orange fruits from huanglongbing (HLB)-infected trees do not fully mature and show a severe off-flavor described as bitter-harsh, metallic, and less juicy and fruity. The investigation of juice from HLB-infected (HLBOJ) and healthy control oranges (COJ) by gas chromatography-mass spectrometry showed higher concentrations of fruity esters, such as ethyl butyrate and ethyl 2-methylbutyrate, and soapy-waxy alkanals, such as octanal and decanal, in the COJ, whereas the HLBOJ showed higher concentrations of green aldehydes such as hexanal and degradation compounds of limonene and linalool such as α-terpineol. Application of aroma extract dilution analysis on terpeneless peel oil led to the identification of long-chained aldehydes such as ( E, E)-2,4-decadienal, ( Z)-8-tetradecenal, trans-4,5-epoxy-( E)-2-decenal, ( Z)-4-decenal, and octanal with the highest flavor dilution factors among 25 odor-active volatiles in the peel oil of healthy oranges. Taste-guided fractionation and identification of the HLBOJ secondary metabolites followed by sensory validation revealed that flavanoids such as hesperidin may modulate the flavor to evoke the unacceptable harsh/metallic taste impression. Quantitation of the bitter components showed good correlation between the limonoid and flavanoid concentrations with the off-flavor and quality of the oranges obtained throughout the season.

Appetite-Inducing Effects of Homoeriodictyol: Two Randomized, Cross-Over Interventions.

SCOPE: Anorexia of aging, characterized by a decrease in appetite and/or food intake, is a major risk factor of under-nutrition and adverse health outcomes in elderly people. Recent in vitro evidence suggests homoeriodictyol (HED), a naturally occurring, bitter-masking flavanone, as a promising agent to increase appetite and food intake. METHODS AND RESULTS: In two cross-over intervention trials, 30 mg NaHED, either solely (n = 10, Study I) or in combination with a 75 g glucose load (n = 17, study II) were administered to healthy adult subjects. Ratings of hunger were assessed at fasting and either 30 min (Study I) or 120 min (Study II) post intervention. Ad libitum energy intake from a standardized breakfast and plasma changes in hunger-/satiety-associated hormones PYY, GLP-1, ghrelin and serotonin were determined after blood drawings. Effects were more pronounced when NaHED was administered in combination with 75 g glucose since ad libitum energy (+ 9.52 ± 4.60%) and protein (+ 7.08 ± 7.97%) intake as well as plasma ΔAUC ghrelin values increased in study II solely, whereas plasma serotonin concentrations decreased after both interventions. CONCLUSIONS: NaHED demonstrated appetizing effects in healthy adults when administered with a glucose load. Long-term intervention studies are warranted to verify these effects in compromised subjects.