Dysphagia, texture modification, the elderly and micronutrient deficiency: a review.

Dysphagia is an underlying symptom of many health issues affecting a person's ability to swallow. Being unable to swallow correctly may limit food intake and subsequently micronutrient status. The elderly may be the most at risk group of suffering dysphagia as well as most likely to be deficient in micronutrients. The use of texture-modified meals is a common approach to increasing dysphagia sufferer's food intake. The modification of food may affect the micronutrient content and currently there is a limited number of studies focusing on micronutrient content of texture-modified meals. This review considers the prevalence of dysphagia within the elderly UK community whilst assessing selected micronutrients. Vitamin B12, C, D, folate, zinc and iron, which are suggested to be most likely deficient in the general elderly UK population, were reviewed. Each micronutrient is considered in terms of prevalence of deficiency, metabolic function, food source and processing stability to provide an overview with respect to elderly dysphagia sufferers.

Combining Liquid Oral Drugs with Thickener: Compatibility and Changes in Viscosity.

Older adults with oropharyngeal dysphagia (OD) are unable to swallow pills safely, so some of them use liquid-formulated drugs mixed with thickeners to ensure safety. The aim of this study was to analyze the physical compatibility of a group of drugs with a thickener formulated with modified starch (Thick & Easy®). A secondary goal was to evaluate the amount of thickener needed to obtain the thickness levels 2, 3, and 4 defined by IDDSI framework for each drug. For this purpose, the rheological properties of the mixtures obtained were determined. Samples of each drug were prepared and 7, 10, and 12 g of thickener were added. Physical compatibility of the mixtures was observed; the apparent viscosity of the samples was measured using a rotational viscometer, and the results obtained were compared with the reference drug-free sample. We analyzed 45 medicinal products (38 active substances). Three drugs (almagate, ibuprofen, and macrogol) were found to be physically incompatible with the thickener and should not be mixed. Viscosity measurements indicated that clarithromycin and plantago ovata increased the viscosity of the mixture and required lower amount to achieve the target textures (110 cP, 590 cP, and 2620 cP for 7 g, 10 g, and 12 g in drug-free samples, respectively), whereas another subset reduced viscosity and required more thickener. This proved very relevant for acetylcysteine, amoxicillin, calcifediol, ferrous gluconate, fosfomycin, lactitol, lactulose, mepifiline, paracetamol, rivastigmine, sertraline, and tramadol. Measurements were below 1750 cP. Awareness of how each drug behaves when combined with thickeners is essential to avoid potential complications in OD.

A Comparison of Behavior of Transitional-State Foods Under Varying Oral Conditions.

Transitional foods are under-utilized in the adult population as they may provide an opportunity to optimize eating pleasure and nutrition for individuals on a modified texture diet. Yet, little is known about the behavioral properties of transitional foods and no research to date has explored the dissolution of known transitional foods in adults. This study aimed to understand the extent of dissolution of five transitional snacks items in relationship to time, tongue pressure, and amount of saliva. Thirty individuals ages 50 to 88 participated in this study (10 with diagnosed xerostomia). The foods tested included shrimp chips, Baby Mum Mums, the EAT bar, and the Savorease cracker with and without dip. Each test food was placed in the mouth for 5 s or 12 s with or without tongue pressure and then expectorated. Benchtop preparation via the International Dysphagia Diet Standardisation Initiative (IDDSI) protocol was also completed. An IDDSI fork pressure test was then performed on all samples. Significant differences between snacks were found in degree of dissolution, with Savorease crackers dissolving more consistently than all others and Baby Mum Mums dissolving least frequently than all others. Tongue pressure positively influenced the dissolution of some foods, particularly those with decreased rates of dissolution. Differences also existed between testing conditions. Overall, there was a wide variability in degree and speed of dissolution across different transitional foods and testing methods. These findings support the need for individual testing to explore post-oral processing consistency when determining the clinical utility of transitional foods.

Understanding the oral processing of solid foods: Insights from food structure.

Understanding the relationship between the structure of solid foods and their oral processing is paramount for enhancing features such as texture and taste and for improving health-related factors such as management of body weight or dysphagia. This paper discusses the main aspects of the oral processing of solid foods across different categories: (1) oral physiology related to chewing, (2) in-mouth food transformation, (3) texture perception, and (4) taste perception, and emphasis is placed on unveiling the underlying mechanisms of how food structure influences the oral processing of solid foods; this is exemplified by comparing the chewing behaviors for a number of representative solid foods. It highlights that modification of the texture/taste of food based on food structure design opens up the possibility for the development of food products that can be applied in the management of health.

Characterizing the Flow of Thickened Barium and Non-barium Liquid Recipes Using the IDDSI Flow Test.

The use of thickened liquids for dysphagia management has become wide-spread. Videofluoroscopy is commonly used to determine dysphagia severity and to evaluate the effectiveness of interventions, including texture modification, but this requires the use of radio-opaque contrast media. In order for the results of a videofluoroscopy to have validity with respect to confirming swallowing safety and efficiency on different liquid consistencies, it is important to understand the flow characteristics of the contrast media used and how the flow of these stimuli compares to the flow of liquids that are provided outside the assessment context. In this study, we explored the flow characteristics of 20% w/v barium and non-barium stimuli prepared using starch and gum thickeners to reach the slightly, mildly and moderately thick liquid categories defined by the International Dysphagia Diet Standardisation Initiative (IDDSI). Our goal was to identify recipes that would produce stimuli with stable flow properties over a 3 h time frame post mixing. Thickener concentration was titrated to achieve matching flow (i.e., IDDSI Flow Test results within a 1 ml range) across the four stimulus types (non-barium starch, non-barium gum, barium starch, barium gum) within each IDDSI level. The combination of barium and thickeners resulted in further thickening, particularly with starch-based thickening agents. A probe of the influence of refrigeration showed no difference in flow measures between chilled and room temperature stimuli over a 3-h time frame. Overall, recipes with stable flow over three hours were identified for all barium and non-barium liquids tested.

Pathways in formulating foods for the elderly.

The growth of the elderly population worldwide is posing significant challenges to human society. The progressive physical and physiological changes occur with aging, including decreased appetite, incomplete digestion, and reduced absorption of nutrients. A common feature of many elderly people's diets is a deficiency in proteins (especially easily digestible ones) and micronutrients (e.g., vitamins, zinc, iron, and calcium). One of the solutions to this problem is the incorporation of these components into suitably texture-modified foods. There is a dearth of products that meet the needs of the elderly with special medical/health conditions such as dysphagia, osteoporosis, diabetes, and cardiovascular disease, as well as those who are in hospital and palliative care. Future research and development of foods for the elderly must address specific dietary needs of different subgroups of elderly people with underlying health conditions. The existence of different physical and physiological stages of the elderly means that their specific dietary requirements must be considered. This review summarizes current knowledge on nutritional requirements including those with underlying health problems and outlines the research and innovation pathways for developing new foods considering nutrition, texture, flavor, and other sensory aspects.

IDDSI-compliant recipes containing oral contrast agents for radiological dysphagia diagnostics.

Videofluoroscopic swallowing study (VFSS), alongside flexible endoscopic evaluation of swallowing, represents the gold standard for diagnosing swallowing disorders and to determine severity, pathophysiology, and effective interventions, including texture modification. The clinical swallowing examination and assessment supplements these instrumental methods and serves as the basis for the modules of swallowing diagnostics. The adaptation of food and drink consistencies in dysphagia management has become widespread. For valid results of a VFSS with respect to confirming swallowing safety and efficiency of different liquid and food consistencies and textures, the use of uniform recipes containing radio-opaque contrast media is important. Our goal was to identify recipes that would produce consistencies that conform to the liquid and food levels of 0-7, as defined by the International Dysphagia Diet Standardization Initiative (IDDSI), with barium- and iodine-based contrast media, xanthan gum-based thickeners, and other edible components, which also show sufficient contrast on VFSS. In this study, we determined the different recipes using IDDSI testing methods and explored their radiological characteristics using a Philips MultiDiagnost Eleva fluoroscopy system and two different fluid contrast agents: barium- (Micropaque®) and iodine-based (Telebrix®). All recipes showed sufficient contrast on fluoroscopy and could be visualized in the amounts used for swallowing examinations. They were practical and easy to implement in terms of production and availability of the components. The homogeneity of the recipes diminished with higher IDDSI levels, which represent transitional food, but appeared still sufficient for fluoroscopic examination. The opacity did not significantly differ between the barium- and iodine-based contrast media.

Prolonged use of a soft diet during early growth and development alters feeding behavior and chewing kinematics in a young animal model.

In infants and children with feeding and swallowing issues, modifying solid foods to form a liquid or puree is used to ensure adequate growth and nutrition. However, the behavioral and neurophysiological effects of prolonged use of this intervention during critical periods of postnatal oral skill development have not been systematically examined, although substantial anecdotal evidence suggests that it negatively impacts downstream feeding motor and coordination skills, possibly due to immature sensorimotor development. Using an established animal model for infant and juvenile feeding physiology, we leverage X-ray reconstruction of moving morphology to compare feeding behavior and kinematics between 12-week-old pigs reared on solid chow (control) and an age- and sex-matched cohort raised on the same chow softened to a liquid. When feeding on two novel foods, almond and apple, maintenance on a soft diet decreases gape cycle duration, resulting in a higher chewing frequency. When feeding on almonds, pigs in this group spent less time ingesting foods compared to controls, and chewing cycles were characterized by less jaw rotation about a dorsoventral axis (yaw) necessary for food reduction. There was also a reduced tendency to alternate chewing side with every chew during almond chewing, a behavioral pattern typical of pigs. These more pronounced impacts on behavior and kinematics during feeding on almonds, a tougher and stiffer food than apples, suggest that food properties mediate the behavioral and physiological impacts of early texture modification and that the ability to adapt to different food properties may be underdeveloped. In contrast, the limited effects of food texture modification on apple chewing indicate that such intervention/treatment does not alter feeding behavior of less challenging foods. Observed differences cannot be attributed to morphology because texture modification over the treatment period had limited impact on craniodental growth. Short-term impacts of soft-texture modification during postweaning development on feeding dynamics should be considered as potential negative outcomes of this treatment strategy.

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.

Evaluating different levels of papain as texture modifying agent in bovine meat loaf containing transglutaminase.

In this study, bovine meat loaves were produced with different levels of papain (0.00125%, 0.0025%, 0.00375%, and 0.005%) combined with transglutaminase (1%). The effect of this reformulation on pH, instrumental color, water activity, proximate composition, texture, yield, and scanning electron microscopy (SEM) of meat loaves was investigated. In addition, the enzymatic activity of papain was also analyzed. The papain addition increased the pH and the yield of the samples. The hardness was progressively reduced with the increase of papain level. Such changes could be seen through the images recorded by SEM, where an extremely fragmented structure was observed in treatments with higher papain concentration. Papain showed an optimum temperature of 80 °C. This study allowed to observe an intense proteolytic effect in all treatments, despite the papain concentration. Therefore, lower levels should be applied so that the product does not alter its sensory characteristics, such as soft and crumbly texture.

Role of the in-situ-produced dextran by lactic acid bacteria in the texture modification of pea flour pastes.

The application of pea flour (PF) was restricted by the resulting non-satisfying texture of food with a high addition level of PF. Four lactic acid bacteria (LAB) strains with the ability to synthesize dextran (DX) were used to ferment PF in order to modify the texture of PF pastes, screen out promising DX producers, and evaluate the role of the in-situ-produced DX in texture modification. The microbial growth, acidity, and DX contents of PF pastes were first analyzed. Then, the rheological and textural properties of PF pastes after fermentation were assessed. After this, the in-situ-produced DXs in PF pastes were further hydrolyzed, and the corresponding changes were studied. Finally, the protein and starch in PF pastes were hydrolyzed separately to evaluate the role of macromolecular interactions between DX and protein/starch in the texture modification of PF pastes. The four LAB strains were all dominant in PF pastes, and the in-situ-produced DXs by these four strains played a critical role in the texture modification of PF pastes. Among the four DX-positive strains, Ln. pseudomesenteroides DSM 20193 and W. cibaria DSM 15878 were promising DX producers in PF-based media due to their high capacity in synthesizing DX and texture modification. The in-situ-produced DX promoted the formation of a porous network structure that was important for water-holding and texture-retaining. The DX-protein interaction contributed more to the texture modification of PF pastes than did the DX-starch interaction. This study clearly showed the role of the in-situ-produced DX and the DX-protein/starch interactions in the texture modification of PF pastes, which could further guide the utilization of in-situ-produced DXs in legume-based food and promote the exploitation of plant proteins.

The fortification of encapsulated soy isoflavones and texture modification of soy milk by α-lactalbumin nanotubes.

Nanocarriers can improve the dispersibility of hydrophobic bioactive compounds and potentially improve the texture of liquid food formulations. Here, nanotubes (NTs) with a high aspect ratio formed by self-assembly of peptides partially hydrolyzed from α-lactalbumin (α-lac) were used to deliver soy isoflavones (IFs) and modify soy milk texture. IFs encapsulated by nanotube (NT/IFs) via hydrophobic interactions, which had improved dispersibility, with a maximum loading efficiency of 4%. The rheological characterization showed that the nanotubes enhanced the viscoelastic property and long term-stability of soy milk. About 80% of the NT/IFs in soy milk survived simulated in in vitro gastric digestion promoting the release of IFs in the intestinal phase. Overall, this work demonstrated that α-lac nanotubes may be a multi-functional carrier system for hydrophobic compounds providing beneficial changes to functional food texture.

A Review of Food Texture Modification among Individuals with Cerebral Palsy: The Challenges among Cerebral Palsy Families.

Individuals with cerebral palsy (CP) frequently present with multiple feeding problems, which may require food texture modification to ensure safe feeding. This review aims to explore the challenges individuals with CP and their caregiver's face and recommend modified food textures to ensure safety and improve the quality of life and nutritional status. A systematic search was carried out through four databases (i.e., EBSCO (Medline), PubMed, Science Direct, and Web of Science) between January 2011 and May 2022. Out of 86 articles retrieved, seven were selected based on keywords and seven other studies through manual search-five cross-sectional studies, two qualitative studies, one correlational study, one mixed method study, one case-control study, two sections of books, and two educational materials. The findings suggest that preparation and intake of food with modified texture play a necessary role in the safety of swallowing in addition to physical, social, and environmental aspects. Safety was found to be the crucial part of the food texture modification provision besides considering the stress of the caregivers and the nutritional status of individuals with CP. Currently, there are no standard guidelines available pertaining to food texture modification. This led to uncertainties in the dietary provision among caregivers, which may lead to undernourishment. Hence, standard guidelines relating to food texture modification that focuses on food preparation and menus with calorie and nutrient information are timely to be developed.

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.

3D Food Printing Applications Related to Dysphagia: A Narrative Review.

Dysphagia is a condition in which the swallowing mechanism is impaired. It is most often a result of a stroke. Dysphagia has serious consequences, including choking and aspiration pneumonia, which can both be fatal. The population that is most affected by it is the elderly. Texture-modified diets are part of the treatment plan for dysphagia. This bland, restrictive diet often contributes to malnutrition in patients with dysphagia. Both energy and protein intake are of concern, which is especially worrying, as it affects the elderly. Making texture-modified diets more appealing is one method to increase food intake. As a recent technology, 3D food printing has great potential to increase the appeal of textured foods. With extrusion-based printing, both protein and vegetable products have already been 3D printed that fit into the texture categories provided by the International Dysphagia Diet Standardization Initiative. Another exciting advancement is 4D food printing which could make foods even more appealing by incorporating color change and aroma release following a stimulus. The ultra-processed nature of 3D-printed foods is of nutritional concern since this affects the digestion of the food and negatively affects the gut microbiome. There are mitigating strategies to this issue, including the addition of hydrocolloids that increase stomach content viscosity and the addition of probiotics. Therefore, 3D food printing is an improved method for the production of texture-modified diets that should be further explored.

Determining the Impact of Thickened Liquids on Swallowing in Patients Undergoing Irradiation for Oropharynx Cancer.

The current standard for the treatment of oropharynx cancers is radiation therapy. However, patients are frequently left with dysphagia characterized by penetration-aspiration (impaired safety) and residue (impaired efficiency). Although thickened liquids are commonly used to manage dysphagia, we lack evidence to guide the modification of liquids for clinical benefit in the head and neck cancer population. The objective of this study was to assess the impact of slightly and mildly thick liquids on penetration-aspiration and residue in 12 patients with oropharyngeal cancer who displayed penetration-aspiration on thin liquid within 3 to 6 months after completion of radiotherapy. Significantly fewer instances of penetration-aspiration were seen with slightly and mildly thick liquids as compared with thin (P < .05). No differences were found across stimuli in the frequency of residue. Patients with oropharyngeal cancers who present with post-radiation therapy dysphagia involving penetration-aspiration on thin liquids may benefit from slightly and mildly thick liquids without risk of worse residue.

Instrumental texture assessment of IDDSI texture levels for dysphagia management. Part 2: Texture modified foods.

Texture-modified foods and thickened fluids play a major role in clinical treatment for individuals who suffer from swallowing difficulties (known as dysphagia). International Dysphagia Diet Standardization Initiative (IDDSI) developed a standardized terminology and description for texture-modified foods and thickened fluids to allow dysphagia patients to receive the correct consistency of food/drink. While the IDDSI framework provides a consistent texture description (Levels 0-7) and is widely accepted as an international standard, testing and assessment of IDDSI texture level are qualitative in nature and subjective in manner. These methods were proposed primarily for use by frontline carers, but are not most ideal for industrial purposes of quality control of such products. Therefore, the main aim of this work was to develop a quantitative instrumental method that best describes IDDSI levels as an objective framework. A set of test samples, including commercially available instant mashed potato, baby rice cereal, and cooked potato cubes of varying texture, were prepared. Two IDDSI measuring techniques, fork pressure test and spoon tilt test, were used to evaluate texture grades of these samples. Puncture and compression tests based on texture analyzer were used to assess cohesiveness, adhesiveness, firmness, and hardness for each food category (Levels 4-7). Thresholds of cohesiveness and adhesiveness, as well as bands of acceptable firmness and hardness for each food category were clearly identified and are proposed as objective complements to the IDDSI framework.

Healthy Eating Enhances Intrinsic Capacity, Thus Promoting Functional Ability of Retirement Home Residents in Northern Taiwan.

Healthy aging is defined as the process of developing and maintaining functional ability in older age with intrinsic capacity, the composite of all the physical and mental capacities of an individual, being the core. This study was conducted to explore the intervention effects of improved dietary quality on intrinsic capacity. A prospective single-group interventional quasi-experimental study with 59 functional independent older adults from retirement homes were recruited. Texture-modified plant-based dietary supplements were provided. In addition, dietary intake, functional ability, and intrinsic capacity in vitality, locomotion, cognition, and psychological capacity were assessed. Vitality was captured by nutritional status, muscle strength, and cardiorespiratory endurance. Locomotor capacity was assessed based on the performance of physical fitness in backscratch test, chair-sit-and-reach test, chair-stand test, one-foot-standing test, and gaits peed. Psychomotor capacity and cognition were measured by using 15-item Geriatric Depression Scale (GDS-15) and Mini-Mental State Examination (MMSE), respectively. In a 4-month of intervention, after controlling for baseline values and covariates, participants with higher dietary intervention adherence showed a significant improvement over time in vitality captured by cardiorespiratory endurance (Pinteraction = 0.009) and significant improvement in locomotion captured by gait speed (Pclusters = 0.034). A significant decrease in the chair-stand test (Ptime = <0.001) and MMSE (Ptime = 0.022) was observed during the four months of intervention. Enhanced intrinsic capacity further contributed to the improvement of ADL over time (Pinteraction = 0.034). In conclusion, healthy eating enhances intrinsic capacity in vitality and locomotion thus promoting functional ability among older adults.

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.

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.