Objective and quantitative definitions of modified food textures based on sensory and rheological methodology

Effect of Cowpea and Pumpkin Powders on the Physicofunctional Properties, Total Phenolic Content, Antioxidant Activity, and Consumer Acceptability of Soup

Cowpea (Vigna unguiculata) and pumpkin (Cucurbita maxima) play a pivotal role as affordable, nutritious food sources for humans. Low-income households can significantly benefit from supplementing their diet with nutritious and cost-effective locally available ingredients. The aim of this research was to develop a cost-effective soup formulation using ingredients that are readily available from a household garden and suitable for use in the kitchens of families with limited financial resources. The effect of cowpea and pumpkin powders on physicofunctional properties, total phenolic content (TPC), antioxidant activity (AA), and consumer acceptability of the soup were determined. Three composite soup mixes were prepared using various parts of cowpea and pumpkin at a ratio of 1:1. A control soup sample was developed, and the experimental soups were prepared by supplementing the control soup with 5%, 10%, or 15% of each composite soup mix, respectively. The physical properties, functional properties, TPC, AA, and consumer acceptability of soup were determined. The control soup had an appealing golden brown colour. Formulations 1 and 3 showed the highest relative viscosity (80.67-88.91 cP). All the experimental soup formulations had higher rehydration ratios (8-14.7 g/g) and water absorption capacities of 185.7-263.3 g/g compared to the control at 7.7 g/g and 65.7 g/g, respectively. The TPC of Formulation 2 (F2) (0.32-0.54 mg of gallic acid equivalent (GAE)/100 g powder) and Formulation 3 (F3) (0.54-0.63 mg GAE/100 g powder) was higher than Formulation 1 (F1) (0.25-0.32 mg GAE/100 g powder) and the control (0.44 mg GAE/100 g powder). Overall, the cowpea seed powder plus pumpkin fruit powder added at 10% in F2 appeared nearly optimal as a soup mix. It produced an attractive golden brown soup with increased swelling power (SP) and viscosity to assist in swallowing. Soup F1 and F2 scored high in appearance (7.27 and 7.0), aroma (7.1 and 6.7), taste (6.6 and 6.3), and overall acceptability (6.5 and 6.4). Despite having TPC and AA lower compared to F3, F2 containing 15% cowpea seed powder and pumpkin fruit has the potential to be further developed and commercialised due to the relatively high overall consumer acceptability and high acceptability in all sensory attributes.

Dysphagia terminology for texture modified fluid and food: a national survey of speech-language pathologists' practice

PURPOSE

To investigate: (a) Swedish Speech-Language Pathologists (SLPs) dysphagia management with TMC, including terminology, inter-professional collaboration, and knowledge of standard TMC guides; and (b) the current TMC terminology/guides used within university hospitals, in Sweden.

METHOD

Part One surveyed SLPs from 19/21 regions. Recruitment occurred via regional SLP/department managers, the national SLP association and email lists. Non-parametric statistics were employed. Part Two explored TMC guides within the seven university hospitals.

RESULT

The initial survey identified 78 Swedish TMC terms. Overlap of both TMC terms and descriptions occurred. Different terms to describe same/similar textures were used by 70% of the SLPs. Knowledge of established guides was high (>90%), though TMC was often (60%) based on locally developed documents. Collaboration with other professions was reported by 97% of SLPs, however almost half perceived collaboration to be inadequate, citing difficulties with transfer of TMC recommendations. Variance in TMC terms/guides within/across the university hospitals occurred.

CONCLUSION

Variable TMC terminology is used in Sweden, impacting optimal dysphagia management. Future research should focus upon implementation of standardised TMC terminology.

Relationship between rheological properties, sensory perception, and overall acceptability of thickened liquids for dysphagia in young and old healthy individuals

This study investigated the relationship between rheological properties, sensory perception, and overall acceptability in healthy young and old groups for dysphagia thickened liquids. Unflavored (UTL) and flavored (FTLP) thickened liquids were prepared using tap water or pomegranate juice at 10 different viscosity levels. The rheological properties were then evaluated via syringe flow test and line spread test (LST). When the apparent viscosity levels of UTL and FTLP were similar, the syringe test and LST results were also similar, indicating consistent flow behavior. Sensory perception evaluations showed that the young group better distinguished viscosity differences between stages compared to the old group. Regarding overall acceptability, the old group preferred samples with higher apparent viscosity than the young group. Principal component analysis and k-means cluster analysis were used to explore correlations between variables and classify thickened liquids into four groups. This can serve the foundation for standardized texture grades of dysphagia thickened liquids, considering rheological characteristics and sensory profiles.

Bolus rheology of texture adjusted food-Effect of age

Swallowing disorders, or dysphagia, affect a large part of the population due to factors such as degenerative diseases, medication side effects or simply age-related impairment of physiological oropharyngeal function. The management of dysphagia is mainly handles through texture-modified foods of progressively softer, smoother, moister textures, depending on the severity of the disorder. Rheological and physiological-related properties of boluses were determined for a group of five older persons (average age, 74) for a set of texture-modified foods: bread, cheese and tomato and the combination into a sandwich. The softest class was gel food, after which came a smooth timbale; both were compared to boluses of regular food. The subjects chewed until ready to swallow, at which point the bolus was expectorated and measured regarding saliva content, linear viscoelasticity and shear viscosity. The results were compared to those of a previously studied younger group (average age, 38). The general physiological status of the subjects was determined by hand and tongue strength, diadochokinesis and one-legged standing and showed that all subjects were as healthy and fit as the younger group. Age-related properties such as one-legged standing with closed eyes and salivary flow plus bolus saliva content were lower for the older group, but the average chews-until-swallow was surprisingly also lower. Consequently, bolus modulus and viscosity were higher than for the younger group. Overall, the intended texture modification was reflected in bolus rheological and physiological-related properties. Bolus modulus, viscosity, saliva content and chews-until-swallowed all decreased from regular food to timbale food to gel food.

Designing of texture modified fruit juices using food hydrocolloids: Storage influence on viscosity

Elderly individuals require special dietary considerations due to various physiological dysfunctions (such as dysphagia, constipation, etc.) and specific nutritional needs. Dysphagia, the difficulty associated with swallowing can lead to some challenges in containing and transitioning of food or liquids within the mouth, increasing the risk of aspiration pneumonia. Thickening fluid is an effective method for alleviating swallowing difficulties. It works by slowing down the flow of liquids during swallowing, thus reducing the risk of aspiration into the airway. The purpose of this research is to develop texture-modified (TM) fruit juices to cater to the needs of elderly individuals with impaired swallowing abilities. To achieve this goal, we created TM fruit juices thickened with hydrocolloids, specifically guar gum (GG), xanthan gum (XG), and starch (S), at different concentrations. The thickened liquids, classified at three National Dysphagia Diet levels, were stored at 4 °C for three months. Physicochemical analyzes of the fruit juices were performed before and after storage. The sensory differences and flow behaviors of orange juice samples containing ascending concentrations of all studied thickeners were investigated at the end of the three-month storage. The results indicated significant changes in the physicochemical properties of the samples, depending in the type of fruit, the hydrocolloid used, and the storage period. Sensory evaluation revealed that orange juices containing starch were more preferred compared to other samples. Therefore, using orange juice thickened with easily swallowed, and less viscous starch will be a safer option for the elderly and individuals with swallowing difficulties.

Mechanical Properties, Microstructure, and In Vitro Digestion of Transglutaminase-Crosslinked Whey Protein and Potato Protein Hydrolysate Composite Gels

The production of animal protein usually leads to higher carbon emissions than that of plant protein. To reduce carbon emissions, the partial replacement of animal protein with plant protein has attracted extensive attention; however, little is known about using plant protein hydrolysates as a substitute. The potential application of 2 h-alcalase hydrolyzed potato protein hydrolysate (PPH) to displace whey protein isolate (WPI) during gel formation was demonstrated in this study. The effect of the ratios (8/5, 9/4, 10/3, 11/2, 12/1, and 13/0) of WPI to PPH on the mechanical properties, microstructure, and digestibility of composite WPI/PPH gels was investigated. Increasing the WPI ratio could improve the storage modulus (G') and loss modulus (G″) of composite gels. The springiness of gels with the WPH/PPH ratio of 10/3 and 8/5 was 0.82 and 0.36 times higher than that of the control (WPH/PPH ratio of 13/0) (p < 0.05). In contrast, the hardness of the control samples was 1.82 and 2.38 times higher than that of gels with the WPH/PPH ratio of 10/3 and 8/5 (p < 0.05). According to the International Organization for Standardization of Dysphagia Diet (IDDSI) testing, the composite gels belonged to food level 4 in the IDDSI framework. This suggested that composite gels could be acceptable to people with swallowing difficulties. Confocal laser scanning microscopy and scanning electron microscopy images illustrated that composite gels with a higher ratio of PPH displayed thicker gel skeletons and porous networks in the matrix. The water-holding capacity and swelling ratio of gels with the WPH/PPH ratio of 8/5 decreased by 12.4% and 40.8% when compared with the control (p < 0.05). Analysis of the swelling rate with the power law model indicated that water diffusion in composite gels belonged to non-Fickian transport. The results of amino acid release suggested that PPH improved the digestion of composite gels during the intestinal stage. The free amino group content of gels with the WPH/PPH ratio of 8/5 increased by 29.5% compared with the control (p < 0.05). Our results suggested that replacing WPI with PPH at the ratio of 8/5 could be the optimal selection for composite gels. The findings indicated that PPH could be used as a substitute for whey protein to develop new products for different consumers. Composite gels could deliver nutrients such as vitamins and minerals to develop snack foods for elders and children.

Rheological Issues on Oropharyngeal Dysphagia

There is an increasing proof of the relevance of rheology on the design of fluids for the diagnosis and management of dysphagia. In this sense, different authors have reported clinical evidence that support the conclusion that an increase in bolus viscosity reduces the risks of airway penetration during swallowing. However, this clinical evidence has not been associated yet to the definition of objective viscosity levels that may help to predict a safe swallowing process. In addition, more recent reports highlight the potential contribution of bolus extensional viscosity, as elongational flows also develops during the swallowing process. Based on this background, the aim of this review paper is to introduce the lecturer (experts in Dysphagia) into the relevance of Rheology for the diagnosis and management of oropharyngeal dysphagia (OD). In this sense, this paper starts with the definition of some basic concepts on Rheology, complemented by a more extended vision on the concepts of shear viscosity and elongational viscosity. This is followed by a short overview of shear and elongational rheometrical techniques relevant for the characterization of dysphagia-oriented fluids, and, finally, an in-depth analysis of the current knowledge concerning the role of shear and elongational viscosities in the diagnosis and management of OD (shear and elongational behaviors of different categories of dysphagia-oriented products and contrast fluids for dysphagia assessment, as well as the relevance of saliva influence on bolus rheological behavior during the swallowing process).

Instrumental and sensory techniques to characterize the texture of foods suitable for dysphagic people: A systematic review

The interest to characterize texture-modified foods (TMFs) intended for people with oropharyngeal dysphagia (OD) has grown significantly since 2011. Several instrumental and sensory techniques have been applied in the analysis of these foods. The objective of the present systematic review was to identify the most appropriate techniques, especially for the food industry and clinical setting. The search was carried out in three online databases according to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" (PRISMA). Across the multiple trials reviewed, Texture Profile Analysis and the Uniaxial Compression Test were most used as the instrumental technique for solid foods, and the Back Extrusion Test for fluid and semisolid foods. All trials used descriptive analysis as the sensory technique. However, the experimental conditions of the trials lacked standardization. Consequently, the results of the trials were not comparable. To properly characterize the texture of TMFs intended for OD by each technique, an international consensus is needed to establish standardized experimental conditions. Methods based on these techniques should also be validated by collaborative studies to verify repeatability, replicability, and reproducibility.

Dietary fiber in bakery products: Source, processing, and function

Bakery products are prevalently consumed foods in the world, and they have been regarded as convenient dietary vehicles for delivering nutritive ingredients into people's diet, of which, dietary fiber (DF) is one of the most popular items. The food industry attempts to produce fiber-enriched bakery products with both increasing nutritional value and appealing palatability. As many new sources of DFs become available, and consumers are moving towards healthier diets, studies of using these DFs as functional ingredients in baked goods are becoming vast. Besides, the nutrition value of DF is commonly accepted, and many investigations have also revealed the health benefits of fiber-enriched bakery products. Thus, this chapter presents an overview of (1) trends in supplementation of DF from various sources, (2) impact of DF on dough processing, quality and physiological functionality of bakery products, and (3) technologies used to improve the compatibility of DF in bakery products.

A secret of salivary secretions: Multimodal effect of saliva in sensory perception of food

Saliva plays multifunctional roles in oral cavity. Even though its importance for the maintenance of oral health has long been established, the role of saliva in food perception has attracted increasing attention in recent years. We encourage researchers to discover the peculiarity of this biological fluid and aim to combine the data concerning all aspects of the saliva influence on the sensory perception of food. This review presents saliva as a unique material, which modulates food perception due to constant presence of saliva in the mouth and thanks to its composition. Therefore, we highlight the salivary components that contribute to these effects. Moreover, this review is an attempt to structure the effects of saliva on perception of different food categories, where the mechanisms of salivary impact in perception of liquid, semi-solid, and solid foods are revealed. Finally, we emphasize that the large inter-individual variability in salivary composition and secretion appear to contribute to the fact that everyone experiences food in their own way. Therefore, the design of the sensory studies should consider the properties of volunteers' saliva and also carefully monitor the experimental conditions that affect salivary composition and flow rate.

Texture-Modified Food for Dysphagic Patients: A Comprehensive Review

Food texture is a major food quality parameter. The physicochemical properties of food changes when processed in households or industries, resulting in modified textures. A better understanding of these properties is important for the sensory and textural characteristics of foods that target consumers of all ages, from children to the elderly, especially when food product development is considered for dysphagia. Texture modifications in foods suitable for dysphagic patients will grow as the numbers of elderly citizens increase. Dysphagia management should ensure that texture-modified (TM) food is nutritious and easy to swallow. This review addresses how texture and rheology can be assessed in the food industry by placing particular emphasis on dysphagia. It also discusses how the structure of TM food depends not only on food ingredients, such as hydrocolloids, emulsifiers, and thickening and gelling agents, but also on the applied processing methods, including microencapsulation, microgels as delivery systems, and 3D printing. In addition, we address how to modify texture for individuals with dysphagia in all age groups, and highlight different strategies to develop appropriate food products for dysphagic patients.

Influence of thickening agents on rheological properties and sensory attributes of dysphagic diet

Dysphagia is the difficulty during the progression of the bolus from the mouth to the stomach. Modifying the texture of the food is a fundamental factor for safe swallowing in patients with dysphagia since inadequate consistency can result in complications. To personalize and develop diets for dysphagia, understanding, and controlling the rheological and sensory properties of thickeners is useful. This review examines the different types of thickeners used to modify the texture of foods, as well as their influence on rheological properties and sensory attributes to efficiently manage the diet in dysphagia. The study discusses characteristics such as: hardness, viscosity, viscoelasticity, as well as sensory attributes related to rheology. The thickeners xanthan gum, methylcellulose, carboxymethylcellulose, guar gum, linseed, and chia, carboxymethylated curdlan, and konjac glucomannan were reviewed in this work. Sensory evaluations of different foods have already been carried out on some products such as: meats, carrots, soups, pates, and timbales with their modified textures. The sensory attributes measured among hydrocolloids are strongly correlated with rheological parameters. Dysphagic diets should have less hardness and adherence, but with adequate cohesiveness to facilitate chewing, swallowing to protect from aspiration and reduction of residues in the oropharynx. The use of a single type of thickener may not be ideal, their mixtures and synergistic effect can improve the viscous and elastic characteristics of foods, to obtain safe food to swallow and to improve the sensory interest of dysphagic patients. Personalized recommendations with follow-up on swallowing approaches, respecting patient's individuality, explaining thickening agents' differences would be pertinent.

Bolus rheology of texture-modified food: Effect of degree of modification

Swallowing disorders, or dysphagia, require an intake of texture-modified foods progressively softer, smoother, and moister depending on the severity of the disorder. Bolus rheology was determined for five healthy subjects for a set of such solid foods regularly given to dysphagia patients. The softest class was gel food, then a smooth timbale which both were compared to the corresponding regular, un-modified food. The foods investigated were bread, cheese, tomato, and the combination as a sandwich, all for the respective texture class: gel, timbale, and regular food. The subjects chewed until ready to swallow and the expectorated bolus was immediately measured for complex shear modulus and viscosity, and moisture and saliva content were determined. Rheology show that texture-modification influenced bolus rheology with decreased viscosity and modulus for increased degree of modification. Also saliva content as well as chews-to-swallow decreased with degree of modification. Overall, the bolus saliva content was lower for the combination (sandwich) than for the individual components. Saliva content was fairly constant irrespective of food moisture content. The phase angle for all boluses was also relatively constant, indicating a similar bolus structure. All boluses of the texture-modified foods showed high extensional viscosity, which is important for bolus cohesiveness. Bolus rheology rather than food texture determines if a food is safe to swallow and the results show that the intended texture-modification is reflected in the flow properties of the respective boluses.

Physical properties of a model set of solid, texture-modified foods

Those suffering from swallowing disorders, or dysphagia, require texture-modified foods for safe swallowing. The texture is modified according to the severity of the disorder, as maintained by the guidelines outlining classes of texture-modified foods, ranging from viscous soups to soft, solid foods. As a basis for studies of bolus rheology and oral response of solid texture-modified foods, a set of well-defined, solid foods has been identified and characterized regarding texture and physical properties. Gelled food is compared to both the firmer timbale class and to the corresponding regular food. Foods eaten at room temperature were chosen to avoid temperature effects: bread, cheese, tomato, and the combination into a sandwich. All foods were tested as gel, timbale, and regular food. The texture was determined by compression and penetration tests, thereby showing a decrease in strength (compression stress), stiffness (modulus), and penetration force for increased degree of modification. The moisture content increased with increased degree of modification. The structural change from room to oral temperature was monitored by the complex shear modulus that showed a decrease with increasing temperature. Cheese and the gelatine-based tomato gel showed a distinct melting when the temperature was increased to 37°C. The texture-modified foods were softer and moister in all aspects as compared to the regular foods, which follows the intended modification. The classes for the texture-modified foods were qualitatively comparable to other national classification systems with regard to solid foods, but there is a lack of objective, physics-based classification of texture, especially for solid, texture-modified foods.

Liking, preference and practical implications of protein and energy enriched in-between-meals designed for elderly people

Background

An adequate dietary intake, especially of protein and energy, is important for maintaining health among elderly people, especially those in care homes. One strategy to ensure nutritional intake is to customise attractive products through enrichment to match the needs of elderly people in care homes.

Objective

To evaluate liking and practical aspects of protein and energy enriched in-between meals designed for elderly people in care homes through the use of quantitative and qualitative assessments.

Design

A broad range of energy and protein enriched in-between meals, including both savoury and sweet products, were included. The products were evaluated by a consumer test and a focus group discussion with elderly respondents. The products were also evaluated by a second focus group discussion with care staff.

Results

The most liked products were ice cream and cheesecake. All products achieved high scores for appearance, taste/flavour and texture. No product included in the study was extremely disliked. However, the least liked product was tomato soup, which scored above the middle of the scale except for texture. It was clear from the focus group discussions that a colourful appearance, small portion size and texture were of primary importance. The temperature had an impact on liking and swallowability.

Discussion

Most products were perceived by the elderly participants as appealing and tasting good, and possible to include in a daily diet. It was clear that the colours of the foods were of primary importance. In line with other studies, it was found that highly liked in-between meals were frozen, cold and sweet. These products were also easy to swallow.

Conclusions

It is possible to produce highly liked energy and protein enriched in-between meal products designed for elderly people. The temperature had a great impact on the liking of texture, taste and flavour. In-between meals should preferably be colourful and have a small portion size.

Dysphagia management in Parkinson's disease: Comparison of the effect of thickening agents on taste, aroma, and texture

Dysphagia is a frequent symptom in Parkinson's disease (PD). Thickening liquids facilitates safe swallowing, however, low treatment compliance is a major issue, due to patients' dislike of thickened liquids. Some studies suggest a negative impact of gum-based thickeners, currently most used in clinical practice, on sensory properties compared to starch-based thickeners. This has not yet been investigated in PD. This study's aim was to compare taste, texture, and aroma of gum-based and starch-based thickened soups in participants with PD. Gum-based resource thicken up clear (RTUC) and starch-based kitchen products potato starch (PS) and quinoa flour (QF) were evaluated in broccoli soup. Texture, aroma, and taste were characterized by rheology, volatile, and sensory profiling. Thickened soups were evaluated in participants with PD and controls through a paired comparison test. Reduced release of 61.4%, 46.2%, and 38.5% of volatiles was observed after thickening with RTUC, PS, and QF, respectively. Overall taste intensity was reduced in RTUC- and PS-thickened soup, respectively. Taste and aroma of PS-thickened soup were considered more intense by 70.3% and 63.8% of all participants, respectively (n = 36 PD, n = 41 controls), 56.3% preferred the PS-thickened soup's texture . Taste and aroma of QF-thickened soup were considered more intense by 68.1% and 65.6% of all participants, respectively (n = 47 PD, n = 31 controls), 58.0% preferred the QF-thickened soup's texture. Starch-based thickeners demonstrated higher taste and aroma intensity. However, volatile and sensory profiling demonstrated reduced taste and aroma in all thickeners. Combining kitchen products with flavor enhancers may increase palatability of thickened beverages.

Saliva Secretion and Swallowing-The Impact of Different Types of Food and Drink on Subsequent Intake

The oral processing of food is important for eating and digestion in order to gain energy and nutrients. Due to disease, injury, or aging, individuals may experience difficulties in this process. These difficulties often lead to dysphagia, which is associated with malnutrition. Thus, it is of importance to find solutions and strategies to enable food intake. It is well known that sour and/or carbonated foods and drinks increase saliva secretion and trigger the swallowing reflex. However, knowledge regarding how subsequent food intake is impacted is lacking. The aim of this study was to clarify whether sour and/or carbonated foods and drinks had subsequent impacts on swallowing function. Twelve healthy participants evaluated eleven foods and drinks in terms of their ability to increase saliva production and ease the swallowing of subsequent food. Results showed that sourness and carbonation had positive impacts on saliva secretion and swallowing. No correlation was found between the pH/sourness of the foods and the ease of swallowing them. It was concluded that the ingestion of cherry tomatoes, natural yoghurt, and, in particular, citrus juice made swallowing of a neutral cracker easier. These results may be used to increase food intake among dysphagia patients.

Development of a dehydrated fortified food base from fermented milk and parboiled wheat, and comparison of its composition and reconstitution behavior with those of commercial dried dairy-cereal blends

Dehydrated blends of milk and cereal are reconstituted and consumed as a nutritious soup or porridge in many regions; the composition and reconstitution behavior of the blends are likely to impact on nutritional quality and consumer acceptability of the soup/porridge. Experimental samples of dried fermented milk-bulgur wheat blend (FMBW) and commercial samples of dried dairy-cereal blends, namely kishk, tarhana, and super cereal plus corn-soy blend (SCpCSB) were compared for composition, color, water sorption, and reconstitution characteristics. FMBW blends had higher contents of protein, Ca, lactose and lactic acid, lower levels of salt (NaCl) and Fe, and a lighter, more-yellow color (higher L* and b*-color co-ordinates) than tarhana or kishk. Compared with SCpCSB, FMBW had numerically higher levels of protein, lactose, and lactic acid, lower levels of Ca, Fe, Zn, and Mg, and lower pH. Tarhana had highest mean levels of starch, and on reconstitution (133 g/kg) had highest water holding capacity, viscosity during pasting and cooling, yield stress (σ 0), consistency coefficient (K), and viscosity on shearing from 20 to 120 s-1 at 60°C. Reconstituted FMBW, kishk, and SCpCSB had similar pasting and flow behavior properties. Overall, the composition (starch, protein, Ca, Mg), pasting and flow behavior characteristics of FMBW were closer to those SCpCSB and kishk than to tarhana. The results suggest that the FMBW powder, on appropriate supplementation with Ca, Fe, Zn and Mg, could be used for the development of customized fortified blended foods for specific groups.

Rheological studies on the effect of different thickeners in texture-modified chicken rendang for individuals with dysphagia

Texture-modified food has become an important strategy in managing dysphagia. Pureed food is proven to be the safest texture due to its high viscosity which can slow down the rate of the food bolus during swallowing. In this study, texture-modified chicken rendang was developed according to Texture C (smooth puree) as described by the Australian standard for texture-modified food. Samples were added with five different thickeners (sago starch, tapioca starch, modified corn starch, xanthan gum and carboxymethyl cellulose gum) at three different concentrations (10, 20 and 30% w/w). Their rheological effects were analyzed through dynamic and steady shear test. Results obtained reveals that samples contained xanthan gum have higher structure rigidity and shear thinning behaviour, while carboxymethyl cellulose gum provides the highest viscosity as well as yield stress than other samples. In terms of concentration, a strong dependence of structural rigidity and viscosity of all prepared samples with amount of thickeners added was observed. Overall, based on its rheological properties, the addition of carboxymethyl cellulose gum at 30% concentration was found to be the most suitable thickener, to be incorporated in the texture-modified chicken rendang. Selecting a suitable food thickener in developing food for individual with dysphagia plays an important role to ensure the right texture and consistency for their safe consumption.

Modifying the consistency of food and fluids for swallowing difficulties in dementia

BACKGROUND

People with dementia can have feeding and swallowing difficulties (dysphagia). Modification of the consistency of food or fluids, or both, is a common management strategy. However, diet modification can affect quality of life and may lead to dehydration and malnutrition. Evidence on the benefits and risks of modifying food and fluids is mandatory to improve the care of people with dementia and dysphagia.

OBJECTIVES

To determine the effectiveness and adverse effects associated with modifying the consistency of food and fluids in improving oral intake and eliminating aspiration in adults with dysphagia and dementia.

SEARCH METHODS

We searched ALOIS (the Specialised Register of the Cochrane Dementia and Cognitive Improvement Group), the Cochrane Library, MEDLINE via Ovid SP, Embase via Ovid SP, PsycINFO via Ovid SP, CINAHL via EBSCOhost, LILACS via BIREME, ClinicalTrials.gov and the World Health Organization (WHO) Portal on 9 May 2018. We also checked the reference lists of relevant articles to identify any additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs), quasi-RCTs and cluster-RCTs published in any language that measured any of the outcomes of interest. We included trials with adults with a clinical diagnosis of dementia with symptoms and signs of dysphagia confirmed on instrumental assessment. We included participants with all types, stages and severities of dementia. Control groups received either no intervention or interventions not involving diet modification or modification to sensory properties of food.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed for inclusion all potential studies identified. Data were extracted independently along with assessment of methodological quality using standard Cochrane methods. We contacted study authors for additional unpublished information.

MAIN RESULTS

No trials on modification of food met the inclusion criteria. We included two studies that examined modification to fluids. Both were part of the same large multicentre trial and included people with dementia and people with or without dementia and Parkinson's disease. Participation in the second trial was determined by results from the first trial. With unpublished data supplied by study authors, we examined data from participants with dementia only. The first study, a cross-over trial, investigated the immediate effects on aspiration of two viscosities of liquids (nectar thick and honey thick) compared to regular liquids in 351 participants with dementia using videofluoroscopy. Regular liquids with a chin down head posture, as well as regular liquids without any intervention were also compared. The sequence of interventions during videofluoroscopy may have influenced response to intervention. The second study, a parallel designed RCT, compared the effect of nectar and honey thick liquids with a chin down head posture over a three-month period in a subgroup of 260 participants with dementia. Outcomes were pneumonia and adverse intervention effects. Honey thick liquids, which are more consistent with descriptors for 'spoon thick' or 'extremely thick' liquids, showed a more positive impact on immediate elimination of aspiration during videofluoroscopy, but this consistency showed more adverse effects in the second follow-up study. During the second three-month follow-up trial, there were a greater number of incidents of pneumonia in participants receiving honey thick liquids than those receiving nectar thick liquids or taking regular liquids with a chin down posture. There were no deaths classified as 'definitely related' to the type of fluids prescribed. Neither trial addressed quality of life. Risk of bias for both studies is high. The overall quality of evidence for outcomes in this review is low.

AUTHORS' CONCLUSIONS

We are uncertain about the immediate and long-term effects of modifying the consistency of fluid for swallowing difficulties in dementia as too few studies have been completed. There may be differences in outcomes depending on the grade of thickness of fluids and the sequence of interventions trialled in videofluoroscopy for people with dementia. Clinicians should be aware that while thickening fluids may have an immediate positive effect on swallowing, the long-term impact of thickened fluids on the health of the person with dementia should be considered. Further high-quality clinical trials are required.

Particular Alimentations for Nutrition, Health and Pleasure

People around the world select their foods and meals according to particular choices based on physiological disorders and diseases, traditions, lifestyles, beliefs, etc. In this chapter, two of these particular alimentations are reviewed: those of the gourmet and the frail elderly. They take place in an environment where food is usually synonymous of body health disregarding its effects on social, cultural and psychological aspects, including emotions. Based on an extensive literature review, it is proposed that the paradigm changes from food equals health to food means well-being, the latter encompassing physical and physiological aspects as well as psychological, emotional and social aspects at the individual and societal levels. The growing food and nutrition requirements of an aging population are reviewed and special nutritious and enjoyable products available for this group are discussed.

Acceptance of texture-modified in-between-meals among old adults with dysphagia

BACKGROUND AND AIMS

Old adults suffering from dysphagia have difficulties swallowing, chewing and/or eating, and are therefore at high risk of undernutrition. In-between-meals that are texture modified are of particular importance for people suffering from dysphagia. To meet their adequate daily amount of food intake they are recommended to eat 3-5 in-between-meals daily. The aim of the current pilot study was to identify the most liked in-between-meals for old adults based on flavour and describe the basic sensory properties of these in-between-meals. Following, the equality between flavour and appearance-based preferences was investigated.

METHODS

From three nursing homes 30 old adults aged 70 years or older suffering from dysphagia were recruited. They were assessing 20 texture modified in-between-meals based on their flavour and appearance on a 3 point hedonic scale.

RESULTS

When participants were asked to assign liking based on flavour, the most liked in-between-meals were frozen, cold and sweet (vanilla ice cream, strawberry parfait and panna cotta). These meals were among the in-between-meals richest in fat and energy. Liking based on flavour and appearance was equal in 18 out of 20 samples. Furthermore, nutritional and sensory characteristics of the preferred meals were described.

CONCLUSION

Flavour and sensory-based ranking of in-between-meals opens the possibility to design new in-between-meals to old adults with dysphagia, by choosing the most liked in-between-meals to offer the target group.

A review of diet standardization and bolus rheology in the management of dysphagia

PURPOSE OF REVIEW

Texture modification is a widespread practice as a strategy for the management of dysphagia and can be very effective in individual cases. However, it is often performed in a qualitative, subjective manner and practices vary internationally according to multiple sets of national guidelines. This article aims to identify best practice by reviewing the theory and practice of texture modification, focussing on recent advances.

RECENT FINDINGS

Instrumental assessment of texture modification in vivo is challenging, and studies including rheology and perception have indicated that fluid viscosity is only one of many factors affecting texture modification in practice. Systematic reviews have identified a historical lack of high-quality clinical evidence, but recent controlled studies are beginning to identify positive and negative aspects of thickened fluids. Research and practice to date have been limited by the lack of control and standardization of foods and drinks. However in 2015 a not-for-profit organization, the International Dysphagia Diet Standardisation Initiative, has published a framework for texture modification from thin liquids to solid foods based on all the existing documentation and guidance, and the - limited - available clinical evidence.

SUMMARY

Rheology exists in the lab; however, normal practice is often subjective or lacking control and standardization. In the near future, cohesion of practice and the availability of practical standardization tools may increase awareness and use of rheology.

Effect of blanching time on the quality characteristics of elderly-friendly kkakdugi

For the development of elderly-friendly food, the physicochemical properties and preferences of cooked kkakdugi prepared with various blanching times were examined. As fermentation progressed, significant differences in samples were observed with overall decreasing trends of pH, reducing sugar, lightness (L), yellowness (b), and hardness. Titratable acidity, redness (a), and lactic acid increased during the storage time. The preference test showed that the sample blanched for 3 min (SK3) scored the highest in aroma, taste, texture, and overall acceptance. Overall, SK3 was the most preferred as cooked kkakdugi, which helps elderly people suffering from mastication and deglutition.

Development of International Terminology and Definitions for Texture-Modified Foods and Thickened Fluids Used in Dysphagia Management: The IDDSI Framework

Dysphagia is estimated to affect ~8% of the world's population (~590 million people). Texture-modified foods and thickened drinks are commonly used to reduce the risks of choking and aspiration. The International Dysphagia Diet Standardisation Initiative (IDDSI) was founded with the goal of developing globally standardized terminology and definitions for texture-modified foods and liquids applicable to individuals with dysphagia of all ages, in all care settings, and all cultures. A multi-professional volunteer committee developed a dysphagia diet framework through systematic review and stakeholder consultation. First, a survey of existing national terminologies and current practice was conducted, receiving 2050 responses from 33 countries. Respondents included individuals with dysphagia; their caregivers; organizations supporting individuals with dysphagia; healthcare professionals; food service providers; researchers; and industry. The results revealed common use of 3-4 levels of food texture (54 different names) and ≥3 levels of liquid thickness (27 different names). Substantial support was expressed for international standardization. Next, a systematic review regarding the impact of food texture and liquid consistency on swallowing was completed. A meeting was then convened to review data from previous phases, and develop a draft framework. A further international stakeholder survey sought feedback to guide framework refinement; 3190 responses were received from 57 countries. The IDDSI Framework (released in November, 2015) involves a continuum of 8 levels (0-7) identified by numbers, text labels, color codes, definitions, and measurement methods. The IDDSI Framework is recommended for implementation throughout the world.

The role of diet in multiple sclerosis: A review

Multiple sclerosis (MS) is a multifactorial, inflammatory, and neurodegenerative disease of the central nervous system, where environmental factors interact with genetic susceptibility. The role of diet on MS has not been comprehensively elucidated; therefore, through an extensive search of relevant literature, this review reports the most significant evidence regarding nutrition as a possible co-factor influencing the inflammatory cascade by acting on both its molecular pathways and gut microbiota. Since nutritional status and dietary habits in MS patients have not been extensively reported, the lack of a scientific-based consensus on dietary recommendation in MS could encourage many patients to experiment alternative dietetic regimens, increasing the risk of malnutrition. This work investigates the health implications of an unbalanced diet in MS, and collects recent findings on nutrients of great interest among MS patients and physicians. The aim of this review is to elucidate the role of an accurate nutritional counseling in MS to move toward a multidisciplinary management of the disease and to encourage future studies demonstrating the role of a healthy diet on the onset and course of MS.

The production effect in adults with dysarthria: improving long-term verbal memory by vocal production

People show better memory for words read aloud relative to words read silently, the Production Effect (PE). Vocalisation at study makes the produced (aloud) words more distinct than the non-produced (silent) words, hence more memorable. Such encoding distinctiveness is related to the additional processing of aloud words that is later used during retrieval. This study investigated the PE in dysarthric adults, characterised by speech production difficulties. Their memory performance (recognition) was compared to a group of healthy adults. Results showed a PE for both groups. The production benefit was significantly larger for the dysarthric adults, despite their overall memory performance being reduced relative to controls. The results demonstrate long-term verbal memory deficits in dysarthria, and suggest that vocalisation (although impaired) may assist in remembering. Hence, vocalisation may be used in intervention contexts with this population, to compensate for memory decrease.

Nutritional Aspects of Dysphagia Management

This chapter describes the nutritional aspects of dysphagia management by starting with the definition of these two conditions (dysphagia and malnutrition) that share three main clinical characteristics: (a) their prevalence is very high, (b) they can lead to severe complications, and (c) they are frequently underrecognized and neglected conditions. From an anatomical standpoint, dysphagia can result from oropharyngeal and/or esophageal causes; from a pathophysiological perspective, dysphagia can be caused by organic or structural diseases (either benign or malignant) or diseases causing impaired physiology (mainly motility and/or perception disorders). This chapter gathers up-to-date information on the screening and diagnosis of oropharyngeal dysphagia, the consequences of dysphagia (aspiration pneumonia, malnutrition, and dehydration), and on the nutritional management of dysphagic patients. Concerning this last topic, this chapter reviews the rheological aspects of swallowing and dysphagia (including shear and elongational flows) and its influence on the characteristics of the enteral nutrition for dysphagia management (solid/semisolid foods and thickened liquids; ready-to-use oral nutritional supplements and thickening powders), with special focus on the real characteristics of the bolus after mixing with human saliva.

Avaliação reológica e sensorial de espessantes domésticos em diferentes líquidos como alternativa na disfagia

O objetivo desse estudo foi analisar as propriedades reológicas e a aceitabilidade de espessantes domésticos em diferentes líquidos, além de comparar os custos e o valor energético desses espessantes. Avaliaram-se no viscosímetro de Brookfield amostras à base de farinha de fécula de batata, de amido de milho, de polvilho doce e de farinha de arroz, além de dois espessantes comerciais, diluídos em líquidos. Foi realizada, com a participação de 30 avaliadores, a investigação de aceitabilidade dos espessantes em água, leite e suco para os atributos: aparência, consistência, odor, sabor e aceitação global. A viscosidade em água dos espessantes comerciais, do amido de milho e da farinha de arroz não teve diferença estatística significativa entre si. Um dos espessantes comerciais atingiu a consistência “rala”. Os resultados de leites e sucos foram semelhantes quando classificados por consistência. Na aceitabilidade dos atributos odor e sabor para água, o espessante comercial, a fécula de batata, o polvilho doce e a farinha de arroz não apresentaram diferença significativa entre si. No leite, para os atributos odor e sabor as amostras não tiveram diferença significativa entre si e para sucos, o espessante comercial, a fécula de batata e o polvilho doce não apresentaram diferença significativa. A viscosidade de um dos espessantes comerciais não estava adequada para o consumo por pacientes com disfagia, obtendo consistência “rala”. O espessante comercial E.C1F e o amido de milho (AM) apresentaram consistência “mel”, sendo apropriado para o consumo em líquidos. As amostras com leites foram as que apresentaram maiores viscosidades, a maioria obteve consistência “pudim”. A aceitabilidade da E.C1F e da fécula de batata (FB) em leite foram as que mais se destacaram promissoras.

In-house pureed food production in long-term care: perspectives of dietary staff and implications for improvement

Texture modification of foods to a pureed consistency is a common management approach for older adults with dysphagia. Long-term care (LTC) facilities commonly produce some pureed food in-house. This study investigated challenges and preferred practices associated with the production of pureed food in LTC facilities. Nutrition Managers (n = 27) and cooks (n = 26) from 25 Ontario LTC facilities were recruited for one-on-one, semistructured interviews. Interviews were digitally recorded, transcribed, and analyzed using inductive thematic analysis. Four themes arose from the data to exemplify challenges in production, including (a) difficulty in using standardized recipes, (b) varied interpretation of governmental guidelines, (c) lack of consistency in terminology and texture, and (d) wanting to improve the visual appeal. These challenges were reported to reduce the quality of in-house produced pureed food. Preferred practices to overcome these challenges were also provided by participants, such as involving cooks in pureed recipe improvements and tailoring to the specific needs of residents. Incorporation of these practices into pureed food production may help to shape and improve future practice and pureed food products.

The effect of varying ingredient composition on the sensory and nutritional properties of a pureed meat and vegetable

The objective of this research was to investigate the effects of ingredients and preparation methods on the sensory and nutritional properties of pureed turkey and carrots. Turkey samples varying in added liquid and muscle composition were developed. Seasoning application methods were also studied. Pureed carrots were formulated with no added thickener, added modified corn starch, rice cereal, or skim milk powder. Small changes in added liquid and seasoning application altered the perceived texture of the turkey. Pureed carrots with added modified corn starch were more slippery and firm than other samples. The addition of skim milk powder or rice cereal did not alter sensory properties but led to higher protein contents when compared to unthickened carrots. In-house formulations did not differ in sensory ratings of appearance and flavor when compared to commercial products but contained more carbohydrates. Modest changes in recipes for pureed products can improve sensory appeal and nutrient density; quality in-house products are feasible with only minor alterations.

The Need for International Terminology and Definitions for Texture-Modified Foods and Thickened Liquids Used in Dysphagia Management: Foundations of a Global Initiative

Conservative estimates suggest that dysphagia (difficulty swallowing) affects approximately 8 % of the world's population. Dysphagia is associated with malnutrition, dehydration, chest infection and potentially death. While promising treatments are being developed to improve function, the modification of food texture and liquid thickness has become a cornerstone of dysphagia management. Foods are chopped, mashed or puréed to compensate for chewing difficulties or fatigue, improve swallowing safety and avoid asphyxiation. Liquids are typically thickened to slow their speed of transit through the oral and pharyngeal phases of swallowing, to avoid aspiration of material into the airway and improve transit to the esophagus. Food texture and liquid modification for dysphagia management occurs throughout the world. However, the names, the number of levels of modification and characteristics vary within and across countries. Multiple labels increase the risk to patient safety. National standardization of terminology and definitions has been promoted as a means to improve patient safety and inter-professional communication. This article documents the need for international standardized terminology and definitions for texture-modified foods and liquids for individuals with dysphagia. Furthermore, it documents the research plan and foundations of a global initiative dedicated to this purpose.