Whey protein mouth drying influenced by thermal denaturation

Oral tribology of dairy protein-rich emulsions and emulsion-filled gels affected by colloidal processing and composition

Designing nutritious food for the elderly population often requires significant quantities of leucine-rich whey proteins to combat malnutrition, yet high-protein formulations can cause mouth dryness and increased oral friction. This study investigated how various colloidal processing methods and compositions impact the in vitro oral tribological properties of protein-rich emulsions and emulsion-filled gels. Oil-in-water emulsions with oil fractions from 1 wt% to 20 wt% were prepared, alongside emulsion-filled gels containing whey protein isolate (WPI), hydrolysed whey protein (HWP), or a blend of both (10 wt% protein content). Two processing approaches were employed: creating emulsions with an initial 10 w% protein content (M1) and initially forming emulsions with 0.1 wt% protein content, then enriching to a final 10 wt% concentration (M2). The hypothesis was that formulations with HWP or method 2 (M2) would offer lubrication benefits by inducing droplet coalescence, aiding in the formation of a lubricating boundary tribofilm. Surprisingly, the tribological behavior of high-protein emulsions showed minimal dependence on oil droplet volume fraction. However, both HWP-based emulsions and those processed with M2 for WPI exhibited significant friction reduction, which may be attributed to the presence of coalesced oil droplets, supporting our hypothesis. Substituting 50 wt% of WPI with HWP in emulsion-filled gel boli resulted in very low friction coefficients in the boundary lubrication regime, suggesting oil droplet release from the gel matrix. These findings provide insights into designing high-protein foods with improved mouthfeel for the elderly population, necessitating further validation through sensory studies.

What Is Chalky? Investigating Consumer Language and Perception of Fine Particles in Beverages Containing Pea and Potato Starch

Despite its importance as an undesirable food texture, the phenomenon of chalkiness remains understudied. Chalky sensations presumably arise from fine particulates found in foods, but semantic overlap with other common descriptors of small particles, like gritty or sandy, is unclear. Here, we compare the usage of Chalky with related descriptors, and determine the effect of particle size, concentration, and xanthan content on Chalky ratings in a model beverage. A 23 factorial design with starch particle size (D90 = 33.8 and 64.6 µm), starch concentrations (10 and 20% w/v), and xanthan content (0.075 and 0.15% w/v) was used. Participants' salivary flow rate was also assessed. A multi-sip taste test was performed where naïve consumers (n = 82; 39% men, 60% women; age range = 18-79 years) rated the intensity of Chalky, Powdery, Gritty, Sandy, Mouthdrying, and Residual mouthcoating at 0, 30, and 60 s after each of three consecutive sips. All attribute ratings were highly correlated, with Chalky, Powdery, and Residual Mouthcoating being more closely correlated with each other than Gritty or Sandy. Although Chalky was still reported 60 s after consumption, no evidence of build-up was found with repeated sips. A larger size and higher concentration increased Chalky ratings, with the low-salivary-flow group reporting greater ratings for Chalky relative to the high-flow group. Our results suggest consumer percepts of small particles are overlapping but not entirely redundant. This suggests researchers and product developers should carefully distinguish between these descriptors when trying to understand consumer perception of food products containing fine particles.

Older adults' acceptability of and preferences for food-based protein fortification in the UK, France and Norway

Research suggests that as we age, protein intake, recognised as vital for combating negative health outcomes, consistently falls below recommendations in older adults. Decreased food intake, combined with age-related eating complications is a major determinant of this protein undernutrition. If nutritional interventions are to be effective and sustainable, they must enable eating pleasure, cater for personal preferences and be adaptable to different eating patterns. As such, we aimed to identify successful strategies for at-home protein-fortification to empower older adults to take a personalised approach to their nutrition, without requiring a large behavioural change. To explore healthy older adults' (age 70+) acceptability and preferences for at-home protein fortification, European project Fortiphy led discussions with older adults (n = 37) and caregivers of older adults (n = 15) to develop high-protein recipes, which were then utilised in a home-use trial with healthy older adults (n = 158). Each fortified recipe was paired with a questionnaire to rate the ease of preparation and liking, and an end-of-study questionnaire was provided to capture overall opinions and preferences. The uniqueness of this study is that the protein fortified recipes were prepared and tested by older adults themselves, in their own homes. Findings showed that older adults were unaware of the importance of protein in ageing and did not have a desire to fortify their foods at present. Yet, they were positive regarding the concept and highlighted the importance of taste, familiar ingredients, and preferred preparation methods. Cultural preferences across countries were identified as having the most influence on the liking of fortified meals. This study also indicated a need for increased awareness of protein requirements to influence the motivation to use fortification.

A narrative review investigating the potential effect of lubrication as a mitigation strategy for whey protein-associated mouthdrying

Whey is consumed by active adults to aid muscle recovery and growth, the general population as a nutritious convenient food, and by older adults to prevent sarcopenia due to its high leucine content. However, whey protein has poor consumer acceptance in this latter demographic, partially due to mouthdrying. This is thought to result from electrostatic interactions between whey and salivary proteins, mucoadhesion to the oral mucosa, and the inherent astringency of acidity. Previous unsuccessful mitigation strategies include viscosity, sweetness and fat manipulation. This literature review reveals support for increasing lubrication to reduce mouthdrying. However, of the 50 papers reviewed, none have proposed a method by which whey protein could be modified as an ingredient to reduce mouthdrying in whey-fortified products. This review recommends the use of modern technologies to increase lubrication as a novel mitigation strategy to reduce mouthdrying, with the potential to increase consumer acceptance.

Multi-attribute temporal descriptive methods in sensory analysis applied in food science: A systematic scoping review

Among descriptive sensory evaluation methods, temporal methods have a wide audience in food science because they make it possible to follow perception as close as possible to the moment when sensations are perceived. The aim of this work was to describe 30 years of research involving temporal methods by mapping the scientific literature using a systematic scoping review. Thus, 363 research articles found from a search in Scopus and Web of Science from 1991 to 2022 were included. The extracted data included information on the implementation of studies referring to the use of temporal methods (details related to subjects, products, descriptors, research design, data analysis, etc.), reasons why they were used and the conclusions they allowed to be drawn. Metadata analysis and critical appraisal were also carried out. A quantitative and qualitative synthesis of the results allowed the identification of trends in the way in which the methods were developed, refined, and disseminated. Overall, a large heterogeneity was noted in the way in which the temporal measurements were carried out and the results presented. Some critical research gaps in establishing the validity and reliability of temporal methods have also been identified. They were mostly related to the details of implementation of the methods (e.g., almost no justification for the number of consumers included in the studies, absence of report on panel repeatability) and data analysis (e.g., prevalence of use of exploratory data analysis, only 20% of studies using confirmatory analyses considering the dynamic nature of the data). These results suggest the need for general guidelines on how to implement the method, analyze and interpret data, and report the results. Thus, a template and checklist for reporting data and results were proposed to help increase the quality of future research.

Review of protein intake and suitability of foods for protein-fortification in older adults in the UK

Protein is a vital dietary component for combating negative health outcomes associated with malnutrition in older adults, including sarcopenia, functional decline and reduced quality of life. Yet, recommended daily protein intake is consistently unmet, as evidenced in the literature and reaffirmed in this review. Poor appetite is recognized as a major determinant of protein-energy undernutrition and thus fortification of regular food or drinks provides a flexible and relevant approach for older adults with reduced appetite. To increase the likelihood of fortified products being successfully incorporated into the diets of older adults, they must be adaptable to older adults eating patterns, cater for their preferences and take the specific age-related problems that complicate food intake into account. This paper aims to highlight older adults' current sources of protein, shopping habits, typical eating patterns and commonly consumed foods, and hence consider appropriate carriers for protein enrichment. Data were reanalyzed from a combination of freely available UK datasets, including the National Dietary and Nutrition Survey and the Food and You Survey, alongside data purchased from market research consultancy, Kantar. These insights draw attention to the potential suitability of foods for fortification purposes, with the ultimate objective to promote eating pleasure and prevent malnutrition.

Inhibition of Maillard reaction during alkaline thermal hydrolysis of sludge

The Maillard reaction (MR) occurs during the alkaline thermal hydrolysis (ATH) of sludge, which affects the quantity and quality of recovered protein. In this paper, four different sulfites were added to investigate their inhibitory effects on melanoidin production. The results showed that sulfites inhibited melanoidin production during ATH of sludge and the inhibitory rate increased with their concentration. At a concentration of 5.71 g/L, the inhibitory rates of NaHSO₃ on melanoidin were 63.27%. Furthermore, the 3D-EEM (Three-Dimension Excitation-Emission-Matrix) fluorescence spectroscopy and protein testing data showed that the inhibition of melanoidin production was accompanied by an increased protein concentration, and protein increased with increasing sulfites concentration. A 2.5-fold increase in protein concentration with Na₂S₂O₄ significantly enhanced the quantity of protein recovered. Therefore, the addition of sulfite during ATH of sludge reduces the amount of non-biodegradable melanoidin, which in turn benefits protein recovery.

Factors Affecting Adherence, Intake, and Perceived Palatability of Oral Nutritional Supplements: A Literature Review

Oral nutritional supplements (ONS) are a clinically effective and relatively inexpensive way to supplement the diet of patients with, or at risk of, undernutrition. Good adherence is a primary determinant of the effectiveness of ONS. However adherence can be problematic for those with the greatest clinical need, such as undernourished older adults. This review aimed to appraise the available literature for the factors (contextual, personal and product related) affecting patient adherence and perceived palatability of ONS, identify areas requiring improvement and uncover gaps in the evidence to guide the focus of future research. Contextual factors identified were healthcare staff and the timing of administration. Personal factors included sensory changes and motivation which alter experience of and desire to consume ONS. The product's sensory characteristics determined palatability and intake, but undesirable attributes, such as off-flavours, can stem from nutritional ingredients. The contribution made by aroma to older adults' experience of ONS was a comparatively under-researched area. Further research should address this evidence gap to optimise the flavour, aroma profile and palatability for undernourished older consumers, thereby optimising intake. A combined multidisciplinary effort involving strategic expansion of research, industry development and clinical practice should simultaneously address the factors identified, to provide the best approach to improve adherence.

Oral retention of thermally denatured whey protein: In vivo measurement and structural observations by CD and NMR

This study investigated structural changes and the in vivo retention in the oral cavity of heated whey protein concentrate (WPC). Heated WPC was shown to have both a higher retention time in the oral cavity compared to unheated whey protein up to 1 min post swallow, and a concomitant increase in free thiol concentration. Nuclear magnetic resonance and circular dichroism demonstrated structural changes in the secondary and tertiary structures of the WPC upon heating. Structural loss of the β-barrel was shown to increase during heating, leading to the exposure of hydrophobic regions. The increase in free thiols and hydrophobic regions are two factors which are known to increase mucoadhesive strength and hence increase oral retention of heated whey protein which may subsequently increase the perception of mouthdrying.

Investigating Methods to Mitigate Whey Protein Derived Mouthdrying

Mouthdrying is commonly associated with whey protein fortified products. Therefore, mitigating strategies could be key to reducing mouthdrying and maximising the benefits from such products. Currently, few studies have successfully mitigated whey protein derived mouthdrying and this paper aims to investigate different strategies to reduce mouthdrying effects. Accordingly, a series of experiments were carried out with a trained sensory panel (n = 11). Two different whey protein food matrices were tested: (a) whey protein beverages (WPB) varying in lactose (0.05-12.4% w/v) and fat (0.9-7.2% w/v) levels and (b) whey protein fortified snacks: cupcakes with differing whey protein concentrate (WPC) powders (standard and heat-stable) and scones with varying fat content (with and without cream topping). Overall results suggested the tested strategies had limited significant effects on whey protein derived mouthdrying. Increasing lactose (9.4% w/v) in WPBs and fat levels (via cream topping) on scones significantly suppressed mouthdrying. However, all other tested strategies (increasing fat in WPBs and heat-stable WPC in cupcakes) had no significant effect on suppressing perceived mouthdrying. This work demonstrates the challenges with mitigating whey protein derived mouthdrying; however, cross-modal taste suppression and increasing lubrication warrant further investigation.

3D printing of a high protein yoghurt-based gel: Effect of protein enrichment and gelatine on physical and sensory properties

The potential application of 3D printing technology in creating protein-rich desserts with multisensory design was investigated. Yoghurt-gel inks were formulated by varying the concentration of gelatine and whey protein isolate (WPI). Assessment of rheological and textural properties prior to printing, showed that an increase of gelatine concentration from 7.5 to 12.5% w/w increased the yield stress, storage modulus, loss modulus, firmness, and resilience of yoghurt gels. Addition of 12% WPI reduced these effects; creating softer gels with reduced resilience. However, these gels showed stable shape after printing, especially in formulations with higher gelatine concentrations. The changes in textural properties caused by the extrusion process need to be considered when designing yoghurt gels, as a significant reduction in firmness and resilience and an increase in adhesiveness were observed after 3D printing. The more stable and well-shaped 3D printed yoghurt gels were obtained by the combined effect of WPI and gelatine which provided a good balance of appearance, taste, flavour, and mouthfeel attributes evaluated by a trained sensory panel. A consumer study performed with thirty healthy adults showed the potential to improve sensory acceptance through the creation of multisensory layered design.

Identification of aroma compounds in a commonly prescribed oral nutritional supplement and associated changes in olfactory abilities with human ageing

Undernutrition is prevalent in the older adult population. Oral nutritional supplements (ONS) are a clinically effective nutritional intervention, however, patient acceptance of ONS can be limited by their palatability. While sensory attributes such as sweetness and mouthfeel have been investigated, the contribution made by aroma to the perceived flavour of ONS has not been studied. Firstly, this research aimed to identify the aroma active compounds within a commonly prescribed ONS using estimated odour activity values (OAV) and gas chromatography olfactometry mass spectrometry (GC-O-MS). Secondly, age related differences in olfactory detection were explored. Eight aroma active compounds were identified within the ONS, including diacetyl (sweet), isoamyl acetate (banana), dimethyl trisulfide (sulfur) and methanethiol (sulfur). When compared with younger adults (n = 24, 18–44 years), older adults (n = 24, 62–80 years) had higher detection thresholds for all aroma compounds and this was significant for isoamyl acetate (sweet, fruity) and methanethiol (sulfur) (p = 0.01 and p = 0.03, respectively). Thus, a decline in olfactory sensitivity was present in the older subjects included in the study, and this reduced detection sensitivity was aroma specific. Thus, older adults’ flavour perception of ONS likely depends on the combined effect of product factors (the aroma profile) along with age related consumer factors (the degree of impairment in perception). This is a fundamental study which will aid future research into how the aroma profile, and associated age related impairments in perception, shape the global perception of ONS for nutritionally at risk older individuals.

The effect of intense pulsed light on the sensory properties of nonfat dry milk

Our objectives were to examine (1) how intense pulsed light (IPL) processing parameters (exposure time and initial temperature) affected aroma, flavor, and mouthfeel of nonfat dry milk, (2) which levels of each parameter produced aroma, flavor, and mouthfeel changes from an untreated control sample, and (3) whether minimal or intense processing conditions produced a noticeable appearance change from the control. Four exposure times (1, 2, 3, and 4 passes through the IPL chamber) and three initial temperatures (25, 30, and 35℃) were studied with untreated milk powder as the control. The samples were prepared as both milk powder and reconstituted milk for sensory evaluation. Using standard evaluating protocols, trained descriptive analysis panelists rated the aroma, flavor, and mouthfeel of these samples. Panelists compared the appearance of the IPL-treated samples that underwent a minimal or intense processing condition to the control by using a two-out-of-five difference test. Increasing the exposure time led to increased intensities of overall flavor, burnt flavor, and umami taste in both milk powder and reconstituted milk, while increasing temperature increased animal and sulfur aromas in reconstituted milk only. Compared to the control, all levels of exposure time at any initial temperature resulted in increased aroma and flavor including cardboard aroma, sulfur aroma, and brothy flavor in both milk powder and reconstituted milk. Only the 4-pass exposure at the initial temperature of 25℃ changed the appearance of milk powder. However, the appearance change was not noticeable in reconstituted milk. PRACTICAL APPLICATION: The standard evaluation protocols and lexicons provide useful tools for research on milk powder. Additionally, the understanding of critical factors impacting sensory properties will contribute to a better implementation of this decontamination technology.

Age group determines the acceptability of protein derived off-flavour

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Heat-treatment of protein ingredients can impart sulfurous flavours into beverages.

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Sulfurous flavours negatively impacted consumer acceptance of a dairy beverage.

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Older adults had greater acceptance of sulfurous flavours compared to younger adults.

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Diacetyl reduced the negative impact of these compounds for both age groups.

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Best estimate thresholds give a conservative estimate of off-flavour acceptability.

Many older adults fail to meet their daily protein requirements, potentially due to social, physical and medical factors, including sensory and appetite changes. Additionally, our previous research has identified potential sulfurous off-flavours, originating from heat-treatment of protein ingredients, which could play a role in consumer acceptance. This study aims to determine the hedonic impact of these potential off-flavours when added to a dairy beverage, identify the specific off-flavour concentrations which cause rejection by consumers, and lastly investigate difference in acceptance between older and younger consumers. A rejection threshold (RjT) protocol was used, in combination with Best Estimate Thresholds (BET), whereby sulfurous flavours (dimethyl sulfide, dimethyl disulfide and dimethyl trisulfide), and diacetyl were added to create a range of concentrations. 95 participants (younger n = 49, 18–38 years; older n = 46, 60–79 years) tasted 7 pairs of samples (one blank and one with ascending off-flavour concentration) and selected their preferred samples. Sulfurous flavours negatively impacted consumer acceptance, however, the extent to which they impart a negative effect differs between age groups. Younger adults rejected samples containing low concentrations of sulfurous off-flavours (1.55 ppb), however, older adults rejected samples with concentrations over 3 times higher (5.08 ppb). When combined with sulfurous flavours, diacetyl increased the rejection threshold for both groups. In conclusion, these observations imply that a greater quantity of off-flavour may be present before acceptance is reduced in the older consumer group. Moreover, diacetyl demonstrates partial masking abilities of sulfurous off-flavours, and BET gave a more conservative estimate of acceptability. This knowledge will help guide sensory innovation of high-protein beverages for older consumers to support product acceptance and optimal intake.

Whey Protein Derived Mouthdrying Found to Relate Directly to Retention Post Consumption but Not to Induced Differences in Salivary Flow Rate

Whey protein is fortified into beverages to provide functional benefits, however, these beverages are considered mouthdrying. To date whey protein derived mouthdrying has not been quantified using a 'physical measure' in parallel with rated perception. Saliva flow could also relate to whey protein derived mouthdrying, however this has not been previously tested as an intervention. Accordingly, volunteers (n = 40) tested mouthdrying in different whey beverages and the sensory profile was evaluated by a trained sensory panel (n = 10). Volunteers also rated mouthdrying combined with collection of saliva samples post beverage consumption to measure retention to the oral cavity. To modulate saliva flow rate, volunteers both chewed on parafilm (to increase saliva flow) and used cotton wool (to remove saliva) before tasting beverages and rating mouthdrying. Both the volunteers and sensory panel rated whey protein beverages (WPB) as significantly more mouthdrying than the control beverage (whey permeate). The significantly higher rating of mouthdrying from the volunteers coincided with significantly higher protein concentration in saliva samples post WPB consumption, supporting mucoadhesion as the mechanism. Modulating saliva flow did not lead to any difference in rated mouthdrying and future work would be beneficial to evaluate further the influence of natural variation in salivary flow rate.

Influence of Age and Individual Differences on Mouthfeel Perception of Whey Protein-Fortified Products: A Review

Protein needs are considered to increase with age, with protein consumption being associated with many positive outcomes. Protein-fortified products are often used to improve nutritional status and prevent age-related muscle mass loss in older adults. Accordingly, older adults are commonly provided with products fortified with whey protein; however, such products can cause mouthdrying, limiting consumption and product enjoyment. Currently, the extent to which age and individual differences (e.g., saliva, oral health, food oral processing) influence the perception of whey protein-derived mouthdrying is relatively unclear. Previous research in this area has mainly focused on investigating mouthdrying, without taking into account individual differences that could influence this perception within the target population. Therefore, the main focus of this review is to provide an overview of the relevant individual differences likely to influence mouthfeel perception (specifically mouthdrying) from whey protein-fortified products, thereby enabling the future design of such products to incorporate better the needs of older adults and improve their nutritional status. This review concludes that age and individual differences are likely to influence mouthdrying sensations from whey protein-fortified products. Future research should focus more on the target population and individual differences to maximise the benefits from whey protein fortification.

Food Oral Processing-An Industry Perspective

We illustrate how scientific understanding of Food Oral Processing enables food product development with specific benefits for several target populations. in vivo, in vitro, and in silico approaches are discussed in the context of their ability to quantify oral processing from the molecular to the macroscopic scale. Based on this understanding, food structures with enhanced performance in terms of hedonic and nutritional properties as well as appropriateness for age and certain medical conditions can be developed. We also discuss current gaps and highlight development opportunities from an industry perspective.

An Investigation of the Influence of Age and Saliva Flow on the Oral Retention of Whey Protein and Its Potential Effect on the Perception and Acceptance of Whey Protein Beverages

Protein fortified products are regularly recommended to older adults to improve nutritional status and limit sarcopenia. However protein fortification can elicit negative sensory attributes such as mouthdrying. Sensitivity to mouthdrying can increase with age, yet the influence of saliva flow and mucoadhesion remain uncertain. Here, two studies tested different whey protein beverages (WPB); 22 healthy younger volunteers completed a pilot and 84 healthy volunteers from two age groups (18-30; 65+) completed the main study. In both studies salivary flow rates (mL/min) were measured and saliva samples were collected at time intervals post beverage consumption to measure mucoadhesion to the oral cavity, where protein concentration was analysed by Bradford Assay. Volunteers rated perception and acceptability of WPBs in the main study. WPB consumption resulted in significantly increased protein concentration (p < 0.0001) in saliva samples compared with a control whey permeate beverage. Older adults had significantly lower unstimulated saliva flow (p = 0.003) and significantly increased protein concentration (p = 0.02) in saliva samples, compared with younger adults. Heating of WPB significantly (p < 0.05) increased mouthdrying and thickness perception and reduced sweetness compared with unheated WPB. Mucoadhesion is concluded to be a true phenomenon in WPBs and increases with age.

Microneedle-Based Delivery: An Overview of Current Applications and Trends

Microneedle arrays (MNA) are considered as one of the most promising resources to achieve systemic effects by transdermal delivery of drugs. They are designed as a minimally invasive, painless system which can bypass the stratum corneum, overcoming the potential drawbacks of subcutaneous injections and other transdermal delivery systems such as chemical enhancers, nano and microparticles, or physical treatments. As a trendy field in pharmaceutical and biomedical research, its applications are constantly evolving, even though they are based on very well-established techniques. The number of molecules administered by MNA are also increasing, with insulin and vaccines administration being the most investigated. Furthermore, MNA are being used to deliver cells and applied in other organs and tissues like the eyes and buccal mucosae. This review intends to offer a general overview of the current state of MNA research, focusing on the strategies, applications, and types of molecules delivered recently by these systems. In addition, some information about the materials and manufacturing processes is presented and safety data is discussed.

Invited review: Astringency in whey protein beverages

Astringency is the sensation of mouth drying and puckering, and it has also been described as a loss of lubrication in the mouth. Astringency is perceived as an increase in oral friction or roughness. Astringency caused by tannins and other polyphenols has been well documented and studied. Whey proteins are popular for their functional and nutritional quality, but they exhibit astringency, particularly under acidic conditions popular in high acid (pH 3.4) whey protein beverages. Acids cause astringency, but acidic protein beverages have higher astringency than acid alone. Whey proteins are able to interact with salivary proteins, which removes the lubricating saliva layer of the mouth. Whey proteins can also interact directly with epithelial tissue. These various mechanisms of astringency limit whey protein ingredient applications because astringency is undesirable to consumers. A better understanding of the causes of whey protein astringency will improve our ability to produce products that have high consumer liking and deliver excellent nutrition.

Dynamic Changes in Post-Ingestive Sensations after Consumption of a Breakfast Meal High in Protein or Carbohydrate

The obesity epidemic urges exploration of several parameters that play an important role in our eating behaviours. Post-ingestive sensations can provide a more comprehensive picture of the eating experience than mere satiety measurements. This study aimed to (1) quantify the dynamics of different post-ingestive sensations after food intake and (2) study the effect of protein and carbohydrate on hedonic and post-ingestive responses. Forty-eight participants (mean age 20.4) were served a breakfast meal high in protein (HighPRO) or high in carbohydrate (HighCHO) on two separate days using a randomised controlled crossover design. Post-ingestive sensations were measured every 30 min, for 3 h post intake using visual analogue scale (VAS). Results showed a significant main effect of time for all post-ingestive sensations. HighCHO induced higher hedonic responses compared to HighPRO, as well as higher ratings for post-ingestive sensations such as Satisfaction, Food joy, Overall wellbeing and Fullness. HighPRO, on the other hand, induced higher ratings for Sweet desire post intake. The development of sensations after a meal might be important for consumers' following food choices and for extra calorie intake. More detailed knowledge in this area could elucidate aspects of overeating and obesity.

Viscosity drives texture perception of protein beverages more than hydrocolloid type

Hydrocolloids are added to alter rheological properties of beverages but have other properties that can contribute to overall taste and texture perception. In this study, tapioca starch and λ-carrageenan were used to determine how hydrocolloid type, viscosity level (4-6 mPa·s, 25-30 mPa·s, and 50-60 mPa·s at 50 s^-1 ), and complexity of the system (aqueous, skim milk, or whole milk) influence sensory taste and texture of fluids. All fluids were shear thinning; however, skim milk and whole milk solutions that contained carrageenan had much higher low shear viscosity and lower high shear viscosity than those with starch. There was a significant effect of viscosity level on sensory perception of consistency, creamy/oily, mouthcoating, and residual mouthcoating in aqueous, skim milk, and whole milk beverages, and a weak effect of hydrocolloid type. However, normalizing creamy/oily, paste, and mouthcoating against sensory consistency removed the effect of hydrocolloid type. Flavors (cream, cooked, cardboard, and melon/cardboard) were associated with the type of hydrocolloid and milk protein ingredient. Temporal dominance of sensations showed that samples exhibit similar temporal sensory profiles, although the addition of hydrocolloids enhanced dominance of creaminess even in samples without fat. Hydrocolloid type did not significantly influence mouthcoating or the persistence of astringency. Additionally, increasing viscosity from 3 to 74 mPa·s at 50 s^-1 did not suppress perceived sweet or salty taste. The results suggest that in fluid systems with viscosity levels typically found in beverages, textural properties are determined by viscosity and independent of the type of hydrocolloid.

Multispectroscopic analysis and molecular modeling to investigate the binding of beta lactoglobulin with curcumin derivatives

Bovine beta lactoglobulin (β-lg), the major whey protein, has a great affinity for a wide range of organic compounds like fatty acids, retinoletc.