Texture-modified foods for the elderly: Status, technology and opportunities

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.

Polysaccharide-dextrin thickened fluids for individuals with dysphagia: recent advances in flow behaviors and swallowing assessment methods

The global aging population has brought about a pressing health concern: dysphagia. To effectively address this issue, we must develop specialized diets, such as thickened fluids made with polysaccharide-dextrin (e.g., water, milk, juices, and soups), which are crucial for managing swallowing-related problems like aspiration and choking for people with dysphagia. Understanding the flow behaviors of these thickened fluids is paramount, and it enables us to establish methods for evaluating their suitability for individuals with dysphagia. This review focuses on the shear and extensional flow properties (e.g., viscosity, yield stress, and viscoelasticity) and tribology (e.g., coefficient of friction) of polysaccharide-dextrin-based thickened fluids and highlights how dextrin inclusion influences fluid flow behaviors considering molecular interactions and chain dynamics. The flow behaviors can be integrated into the development of diverse evaluation methods that assess aspects such as flow velocity, risk of aspiration, and remaining fluid volume. In this context, the key in-vivo (e.g., clinical examination and animal model), in-vitro (e.g., the Cambridge Throat), and in-silico (e.g., Hamiltonian moving particles semi-implicit) evaluation methods are summarized. In addition, we explore the potential for establishing realistic assessment methods to evaluate the swallowing performance of thickened fluids, offering promising prospects for the future.

Physicochemical Properties of Mixed Gelatin Gels with Soy and Whey Proteins

The physicochemical properties of the mixed gelatin gels with soy and whey proteins were investigated to develop the gel base with a soft texture and abundant essential amino acids for the elderly. Gelatin-only gel (control) was prepared at 6% (w/v), and mixed gelatin gels were formulated by replacing gelatin with soy protein isolate and whey protein concentrate at different mixing ratios [gelatin (G):soy protein isolate (S):whey protein concentrate (W)]. Results showed that replacing gelatin with the globular proteins in gelatin gels increased the pH value and processing yield (p < 0.05). Moreover, the mixed gelatin gels, particularly the G2:S1:W3 treatment, showed significantly higher essential amino acids than the gelatin-only control. The partial replacement of gelatin with the globular proteins could decrease the hardness of gelatin gel (p < 0.05), but there was no difference in hardness between the G2:G3:W1, G2:S2:W2, and G2:S1:W3 treatments (p > 0.05). The results of protein pattern, x-ray diffraction, and microstructure had no clear evidence for specific protein-protein interaction in the mixed gelatin gels. Therefore, this study indicates that mixed gelatin gels with the globular proteins at specific mixing ratios could be a practical approach to providing a soft texture and high-level essential amino acids to the elderly.

Food Processing and Nutrition Strategies for Improving the Health of Elderly People with Dysphagia: A Review of Recent Developments

Dysphagia, or swallowing difficulty, is a common morbidity affecting 10% to 33% of the elderly population. Individuals with dysphagia can experience appetite, reduction, weight loss, and malnutrition as well as even aspiration, dehydration, and long-term healthcare issues. However, current therapies to treat dysphagia can routinely cause discomfort and pain to patients. To prevent these risks, a non-traumatic and effective treatment of diet modification for safe chewing and swallowing is urgently needed for the elderly. This review mainly summarizes the chewing and swallowing changes in the elderly, as well as important risk factors and potential consequences of dysphagia. In addition, three texture-modified food processing strategies to prepare special foods for the aged, as well as the current statuses and future trends of such foods, are discussed. Nonthermal food technologies, gelation, and 3D printing techniques have been developed to prepare soft, moist, and palatable texture-modified foods for chewing and swallowing safety in elderly individuals. In addition, flavor enhancement and nutrition enrichment are also considered to compensate for the loss of sensory experience and nutrients. Given the trend of population aging, multidisciplinary cooperation for dysphagia management should be a top priority.

Consumer Acceptance of Texture-Modified Mackerel Stew Products in Older Adults

Along with concerns regarding societal aging, the dietary requirements of older adults have become a priority. Older adults in Korea experience difficulties consuming animal protein sources as they age. Therefore, this study aimed to develop a senior-friendly food product using mackerel. Accordingly, carbohydrates and proteins were added to the brine solution before saturated vapor treatment. Calcium lactate and poly-gamma-glutamic acid were added to the sauce, and when compared to four commercial products (GT_R, GT_K, PC_K, and AC_G) in an acceptance test, the product was found to exhibit the highest overall liking score (p < 0.001). Higher flavor-liking and familiarity ratings were found to increase purchase intention, while higher flavor-liking, overall-liking, and familiarity ratings increased recommendation intention. Those in mid-to-late adulthood preferred the GT_R and PC_K samples, whereas the AC_G sample was preferred by those in very late adulthood. AC_G sample analysis suggested that those in the very late adulthood group had a relatively higher acceptance of spiciness. In this study, a calcium-added mackerel stew product was manufactured, meeting the standards for senior-friendly food in Korea. It will serve as a baseline for further research on fish- and mackerel-based foods for older adults, which is in its early stages.

Understanding the health benefits and technological properties of β-glucan for the development of easy-to-swallow gels to guarantee food security among seniors

The world's population is growing rapidly and the number of elderly people with undernutrition and malnutrition is increasing. Common health problems among seniors are cardiovascular, inflammatory, gastrointestinal, and cognitive disorders, cancer, diabetes, psychological and dental problems. The food industry is trying to meet the demands of an aging society, but these efforts are not sufficient. New strategies are needed, and they demand foods development with modified textures that are easy to swallow, such as gels suitable for seniors. Depending on the specific needs of the elderly, bioactive compounds with health benefits should be included in food systems. Novel foods may play an important role in the prevention, maintenance, and treatment of age-related diseases. One of the most studied bioactive compound is β-glucan, a polysaccharide with approved health claims confirmed by clinical trials, such as "β-glucan contributes to the maintenance of normal blood cholesterol levels" and "the consumption of β-glucan from oats or barley contributes to the reduction of postprandial glucose spikes." In this review, the health benefits, and technological properties of β-glucan for the development of senior-friendly ready-to-swallow gels were described. In addition, some patents and studies conducted in connection with the development of the gel systems were collected.

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.

Correlating instrumental measurements and sensory perceptions of foods with different textural properties for people with impaired oral and swallowing capabilities - A review

The rising global life expectancy has underlined the necessity of designing novel and tasty food products, suitable for seniors and people with impaired oral and swallowing functions. For developing these products, texture should be optimised from rheological, colloidal, tribological, and masticatory points of view. The current review provides an overview of different studies based on shear rheological, tribological, and in vitro mastication properties of model or real food systems intended for the elderly and/or people with swallowing dysfunctions, with special emphasis on the relation between the instrumental measurements and sensory perceptions of foods. Several works demonstrated that instrumental data from shear rheological and tribological tests complement the sensory evaluations of foods, providing useful information when designing food commodities for specific populations. Conversely, only few works correlated the instrumental data obtained from artificial mouths and/or simulated masticators with the sensory attributes generated by trained assessors. Broaden knowledge of these topics will help in formulating and adapting foods with enhanced functionalities for people with impaired oral and swallowing capabilities. Shear rheology, soft oral tribology, and simulated mastication tests are crucial in designing safe- and easy-swallowing food products.

Development of meat spread with omega-3 fatty acids derived from flaxseed oil for the elderly: Physicochemical, textural, and rheological properties

This study evaluates the characteristics of n-3-enriched meat spread that is in development for consumption by elderly individuals. Herein, flaxseed oil was used as a source of n-3 fatty acid, and macro- and nano-sized flaxseed oil emulsions (FOE) were prepared for the fabrication of meat spreads. As the level of FOE was increased in the meat spreads, significant increases in the levels of omega-3 fatty acids (α-linolenic acid) were observed. Emulsion stability and cooking loss were also improved in meat spreads formulated with FOE compared with those the control. In particular, the addition of FOE generated softer and less chewy meat, owing to its lower melting point and rheological properties. However, the high content of unsaturated fatty acids in the FOE-containing meat spreads increased their susceptibility to lipid oxidation meat. These findings indicate that FOE, particularly macro-sized FOE, has the potential for use in n-3 fatty acid enriched meat products that are intended for consumption by elderly individuals but need to be evaluated for their impacts on shelf-life and sensory quality.

Impact of a moulded pureed diet on taste, appearance, recognisability, and overall liking among patients in an acute hospital

Introduction

Hospital meals potentially influence patients' nutritional, physical, and emotional well-being during their admission. Patients on pureed diets report poorer meal satisfaction, due to taste, appearance, and recognisability, potentially impacting on their nutritional status. This study compared whether a moulded pureed diet made from modified maize starch led to improved taste, appearance, recognisability, and overall liking, compared to an unmoulded pureed diet made from potato starch in an acute hospital.

Methods

Patients on texture-modified diets were recruited and presented with two pureed diets - unmoulded and moulded. Participants were asked to identify meat and vegetable dishes prior to eating. After the meal, participants indicated their diet preference in terms of appearance, taste, and overall liking.

Results

145 participants were recruited, of which 126 completed data collection. 86% correctly identified moulded meat dishes, 69% correctly identified moulded vegetable dishes, with an overall 77% accuracy in identifying moulded puree side dishes. On unmoulded puree side dishes, participants correctly identified 25% of meat dishes, 4% of vegetable dishes, with an overall accuracy of 14%. In terms of preference, the moulded puree was preferred, with 81% for appearance, 76% for taste and 75% for overall preference. When participants had differing preferences for appearance and taste (e.g., prefers unmoulded puree appearance and moulded puree taste), 95% of them subsequently aligned their overall preference with their taste preference (i.e., overall preferred moulded pureed diet). This suggests that taste has a stronger influence on overall preference compared to appearance.

Discussion

Findings indicate that a moulded pureed diet made from modified maize starch led to improved recognisability, taste, appearance, and overall liking compared to an unmoulded pureed diet made from potato starch. Taste had a stronger influence on overall preference compared to appearance. These findings capture patient preferences and may have implications on how hospital pureed diets may be improved, potentially improving patient nutrition and health outcomes.

Oral bioavailability of bioactive compounds; modulating factors, in vitro analysis methods, and enhancing strategies

Foods are complex biosystems made up of a wide variety of compounds. Some of them, such as nutrients and bioactive compounds (bioactives), contribute to supporting body functions and bring important health benefits; others, such as food additives, are involved in processing techniques and contribute to improving sensory attributes and ensuring food safety. Also, there are antinutrients in foods that affect food bioefficiency and contaminants that increase the risk of toxicity. The bioefficiency of food is evaluated with bioavailability which represents the amount of nutrients or bioactives from the consumed food reaching the organs and tissues where they exert their biological activity. Oral bioavailability is the result of some physicochemical and biological processes in which food is involved such as liberation, absorption, distribution, metabolism, and elimination (LADME). In this paper, a general presentation of the factors influencing oral bioavailability of nutrients and bioactives as well as the in vitro techniques for evaluating bioaccessibility and is provided. In this context, a critical analysis of the effects of physiological factors related to the characteristics of the gastrointestinal tract (GIT) on oral bioavailability is discussed, such as pH, chemical composition, volumes of gastrointestinal (GI) fluids, transit time, enzymatic activity, mechanical processes, and so on, and the pharmacokinetics factors including BAC and solubility of bioactives, their transport across the cell membrane, their biodistribution and metabolism. The impact of matrix and food processing on the BAC of bioactives is also explained. The researchers' recent concerns for improving oral bioavailability of nutrients and food bioactives using both traditional techniques, for example, thermal treatments, mechanical processes, soaking, germination and fermentation, as well as food nanotechnologies, such as loading of bioactives in different colloidal delivery systems (CDSs), is also highlighted.

Formulation of Ready-to-Eat Soup for the Elderly: Nutritional Composition and Storage Stability Study

Lack of appetite is a common problem in elderly people which could lead to the risk of malnutrition. Soup-based product formulation and supplementation for the elderly is an interesting and convenient way to maintain nutritional status. Hence, this study aims to develop ready-to-eat (RTE) soup and instant soup powder using common agricultural commodities. The results indicated that among all formulations, the F7 formula comprised brown rice (15 g), pumpkin (32.5 g), sweetcorn (12.5 g), red tilapia (17.5 g), rice bran oil (1.0 g), and water (21.5 g) with energy ratio (C:P:F) of 58:23:20 receiving the highest sensory scores. The selected formulation (F7) was also transformed into instant powder and both RTE soup and instant powder were evaluated for nutritional composition and storage stabilities at 5 °C and 25 °C, respectively. The nutritional composition analyses indicate that 100 g of RTE soup consists of 13.8 g carbohydrates, 4.9 g proteins, 1.8 g fats, and 1.5 g dietary fibers; the soup is also a rich source of antioxidants and β-carotene. Storage studies suggested that the content of β-carotene and antioxidant activity of both (ready-to-eat and instant powder) types of soup decreased with increasing storage time, while a slight increase in yeast and mold count (<50 cfu/g) was noted. Most importantly, no pathogenic bacteria were detected in ready-to-eat and instant soup during the storage study of 6 weeks at 5 °C and 6 months at 25 °C, respectively. In terms of the high nutritional composition and functional value of the product, 4 weeks of storage at 5 °C and 4 months of storage at room temperature were suggested for ready-to-eat and instant powder soup product, respectively.

Study the correlation between the instrumental and sensory evaluation of 3D-printed protein-fortified potato puree

The creation of 3D printed food with programmed texture has the ambition of getting personalized properties through novel texture perceptions with many different ingredients and is helping the swallowing or mastication problems of vulnerable people. This study is done to determine the correlation between the instrumental and sensory evaluation of 3D-printed protein-fortified puree potatoes. At the moment there are not many studies about this correlation, and this information can be very helpful for food texture development. For people with swallowing difficulties, it is critical to have access to safe food with the desired texture. Therefore, understanding the correlation between texture-modified food will aid in the formulation of safe foods with desired sensory properties. Instrumental measurements of fortified puree were performed by a texture analyzer and the attributes obtained were firmness, consistency, cohesiveness, and index of viscosity. Quantitative descriptive analysis with eight trained panelists was employed to characterize the texture of the the3D-printed protein-fortified puree based on six sensory attributes: firmness, thickness, smoothness, rate of breakdown, adhesive, and difficulty swallowing. Three proteins (soy, cricket, and egg albumin with two different concentrations of 3 and 5%) were evaluated against puree potato without any protein as a control. The correlation results obtained from texture analysis and sensory evaluation were statistically significant (P < 0.05) which can be used to understand the impact of ingredients on textured modified puree to predict the sensory attributes which need a lot of time for training panelists.

Application of Rapeseed Meal Protein Isolate as a Supplement to Texture-Modified Food for the Elderly

Rapeseed meal (RSM), a by-product of rapeseed oil extraction, is currently used for low-value purposes. With a biorefinery approach, rapeseed proteins may be extracted and recovered for high-end uses to fully exploit their nutritional and functional properties. This study reports the application of RSM protein isolate, the main output of a biorefining process aimed at recovering high-value molecules from rapeseed meal, as a supplement to texture-modified (TM) food designed for elderly people with mastication and dysphagia problems. The compositional (macronutrients by Official Methods of Analyses, and mineral and trace element profiles using Inductively Coupled Plasma Optical Emission Spectrometry ICP-OES), nutritional and sensory evaluations of TM chicken breast, carrots and bread formulated without and with RSM protein supplementation (5% w/w) are hereby reported. The results show that the texture modification of food combined with rapeseed protein isolate supplementation has a positive impact on the nutritional and sensory profile of food, meeting the special requirements of seniors. TM chicken breast and bread supplemented with RSM protein isolate showed unaltered or even improved sensory properties and a higher nutrient density, with particular regard to proteins (+20-40%) and minerals (+10-16%). Supplemented TM carrots, in spite of the high nutrient density, showed a limited acceptability, due to poor sensory properties that could be overcome with an adjustment to the formulation. This study highlights the potentialities of RSM as a sustainable novel protein source in the food sector. The application of RSM protein proposed here is in line with the major current challenges of food systems such as the responsible management of natural resources, the valorization of agri-food by-products, and healthy nutrition with focus on elderly people.

Feasibility of hydrocolloid addition for 3D printing of Qingtuan with red bean filling as a dysphagia food

Glutinous rice flour, the main component of Qingtuan, has increased adhesiveness after gelatinization and hardness after aging; this results in great challenge in swallowing if for patients with dysphagia. Dual nozzle 3D printing has great potential for developing innovative Chinese pastries with fillings that conform to dysphagia diets. In this experimental study, the gelatinization and retrogradation behavior of glutinous rice starch was improved by designing printing inks of optimal properties made with different soluble soybean polysaccharide (SSPS) additions (0%, 0.3%, 0.6%, 0.9%). The internal structure of Qingtuan was modified by adjusting different filling densities (75%, 100%) in combination with the dual nozzle 3D printing. The objective of these tests was to enhance the texture of Qingtuan so that it meets the requirements of International Dysphagia Diet Standardization Initiative (IDDSI). The experimental results showed that 0.9% SSPS addition could effectively reduce the hardness and adhesiveness of the Qingtuan, which met the Level- 6 -soft & bite-sized standard while lower filling density lowers both hardness and adhesiveness.

Rheological, textural, and water-immobilizing properties of mung bean starch and flaxseed protein composite gels as potential dysphagia food: The effect of Astragalus polysaccharide

The effects of Astragalus polysaccharide (APS) on rheological, textural, water-holding, and microstructural properties of mung bean starch (MBS)/flaxseed protein (FP) composite gels were investigated. Results showed that the storage modulus (G') of gels with APS were significantly lower than that of the control gel, while different concentrations of APS possessed diverse effects on the hardness, gumminess and cohesiveness of the gels. Adding APS significantly improved the water retention capacity by trapping more immobilized and free water in the gel network. Microstructurally, the MBS/FP/APS composite gels displayed a complex network with reduced pore size compared with that of the control gel (MBS/FP). International dysphagia diet standardization initiative (IDDSI) tests suggested that gels with APS contents below 0.09 % could be classified into level 6, while gel with 0.12 % APS could be categorized as level 7. Mechanistically, APS could influence the interactions between starch and protein within the tri-polymeric composite systems by affecting starch gelatinization and hydrogen bonding, further contributing to the formation of strengthened gel network and the change of gel properties. These results suggest that the macromolecular APS can improve the structural and textural properties of the starch-protein composite systems, and impart various functional properties to the FP-based gel foods.

pH-shifting alters textural, thermal, and microstructural properties of mung bean starch-flaxseed protein composite gels

The objective of this study was to investigate the effect of pH-shifting on the textural and microstructural properties of mung bean starch (MBS)-flaxseed protein (FP) composite gels. Results showed that different pH-shifting treatments caused changes in hydrogen bond interactions and secondary structures in composite gels, leading to the formation of loose or compact gel networks. The pH 2-shifting modified protein and starch molecules with shorter chains tended to form smaller intermolecular aggregates, resulting in the formation of a looser gel network. For pH 12-shifting treatment, conformational change of FP caused the unfolding of protein and the exposure of more hydrophobic groups, which enhanced the hydrogen bond and hydrophobic interactions between polymers, contributing to the formation of a compact gel network. Furthermore, pH 12-shifting improved the water-holding capacity (WHC), storage modulus, and strength of gels, while pH 2-treated gels exhibited lower WHC, hardness, and gumminess due to the degradation of MBS and denaturation of FP caused by extreme acid condition. These findings suggest that pH-shifting can alter the gel properties of bi-polymeric starch-protein composite systems by affecting the secondary structures of proteins and the hydrogen bonding between the polymers, and provide a promising way for a wide application of FP in soft gel-type food production.

Effects of hydrolysed meat on dietary intake and nutritional status in aged care residents requiring pureed diets: a crossover randomised controlled trial

BACKGROUND

As a result of the high prevalence of dysphagia in aged care facilities, demand for pureed diets is increasing. One of the biggest challenges for pureed diets is the reduced nutritional density due to the cooking process, such as when blending or softening with liquid. This study aimed to investigate the impact of innovative energy and protein-enriched meat puree on the nutrition intake and nutritional status of aged care residents requiring pureed diets.

METHODS

This is a single-blinded randomised controlled trial conducted in two aged care facilities using a crossover design. Twenty-two residents aged 83.2 ± 7.3 years participated in a 12-week study. Participants were blocked randomised into two groups and received a 6-week of either control (unaltered freshly made pureed diets by facilities) or intervention diet, followed by a 2-week washout and then 6-week of alternative treatment. During the intervention, freshly made meat pureed portions were swapped to hydrolysed meat, which contained 144 -392 kcal and 5.6-6.8 g more energy and protein per 100 g. Nutrition intake was collected using a validated visual estimation method over 24 h on two non-consecutive days during the control and intervention phases. A two-tailed t-test was used to compare the significance.

RESULTS

The intervention diet significantly increased energy (147 ± 285 kcal, p = .02), protein (4 ± 7 g, p = .04), and fat (3 ± 8 g, p = .07) intake in comparison to the control diet. Nutritional status was improved by the end of the intervention as evidenced by a higher nutritional assessment score using Mini-Nutritional Assessment - Short Form (9.1 ± 1.8) and a weight gain of 1.3 ± 1.7 g, p = .04. No significant differences were found in body composition using bioelectrical impedance analysis, calf circumference and mid-upper arm circumference. Though handgrip strength did not differ at the end of control and intervention, significance was found between the changes in control and intervention period. Plasma branched-chain amino acid increased significantly with hydrolysed meat consumption.

CONCLUSIONS

As a dietary enrichment, hydrolysed meat is a promising intervention for pureed diet consumers in aged care facilities, improving residents' dietary intake and reducing malnutrition risk. Future larger multicentre studies with longer intervention periods are required to confirm the effectiveness and residents' acceptance.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ACTRN12622000888763).

Opportunities and barriers for food intake in older age - a Norwegian perspective

Background

The ageing processes occur slowly over time and are often not detectable by the individual. Thus, preparing for dietary needs in later years should start at an earlier age than most people realise.

Objective

This study aims at better understanding what characterises food-related practices in active, home-living older adults, in order to identify food-related factors that act as barriers and those that promote healthy ageing.

Design

Three experiments were conducted: First, a web-based quantitative survey to collect information about home-living older adults' food-related behaviours (67+ years, N = 1,005). Second, two focus groups with respondents 67-74 years (N = 7) and 75-84 years (N = 6) to elicit aspects not adequately covered in the survey. Third, 10 individual interviews to provide in-depth insights.

Results

Two distinct groups were identified in the survey; 67-79 years and 80+ years. The older age group experienced more barriers and restrictions in food intake and food-related behaviours compared to the younger group. Good taste, routines and social settings were important for appetite and food intake.

Discussion

Using a mixed-methods approach proved valuable for extracting information and a better understanding of what impacts on food-related aspects amongst older adults. Strategies for upholding a healthy food intake involve establishing daily routines and meeting arenas where older adults can socialise and eat food together.

Conclusion

This study confirmed that knowledge of older adults' physical needs, barriers and abilities must be a part in preparation for a healthy diet.

Physicochemical Characterization of Texture-Modified Pumpkin by Vacuum Enzyme Impregnation: Textural, Chemical, and Image Analysis

Texture-modified pumpkin was developed by using vacuum enzyme impregnation to soften texture to tolerable limits for the elderly population with swallowing and chewing difficulties. The impregnation process and macrostructural and microstructural enzyme action were explored by the laser light backscattering imaging technique and a microscopic study by digital image analysis. Texture was analyzed by a compression assay. The effect of enzyme treatment on antioxidant capacity and sugar content was evaluated and compared to the traditional cooking effect. Image analysis data demonstrated the effectiveness of the impregnation process and enzyme action on plant cell walls. Enzyme-treated samples at the end of the process had lower stiffness values with no fracture point, significantly greater antioxidant capacity and significantly lower total and reducing sugars contents than traditionally cooked pumpkins. The results herein obtained demonstrate the capability of using vacuum impregnation treatment with enzymes to soften pumpkins and their positive effects on antioxidant capacity and sugar content to develop safe and sensory-accepted texture-modified products for specific elderly populations.

Meat texture modification for dysphagia management and application of hydrocolloids: A review

Dysphagia is a medical condition that describes the difficulty of swallowing food, and texture modified food (TMF) is the best intervention for dysphagia. The relevant guidelines to identify dysphagia food are provided by the International Dysphagia Diet Standardization Initiative (IDDSI). Developing texture modified meat is a challenging task due to its fibrous microstructure and harder texture. Various meat tenderization attempts are therefore evaluated in the literature. Meat texture modification for dysphagia is not just limited to tenderization but should be focused on safe swallowing attributes as well. The application of hydrocolloids for designing TMF has a major research focus as it is a cost-effective method and offers an opportunity for careful control. The present review focuses on the meat texture modification attempts that have been used in the past and present, with special attention to the use of hydrocolloids. Several studies have shown improvements in texture upon the addition of various hydrocolloids; however, few studies have attempted to develop texture modified meat for people with dysphagia. This area has to be further developed along with the sensory evaluations conducted with the dysphagia population, to validate the industrial application of hydrocolloids to TMF.

The fourth industrial revolution in the food industry-part II: Emerging food trends

The food industry has recently been under unprecedented pressure due to major global challenges, such as climate change, exponential increase in world population and urbanization, and the worldwide spread of new diseases and pandemics, such as the COVID-19. The fourth industrial revolution (Industry 4.0) has been gaining momentum since 2015 and has revolutionized the way in which food is produced, transported, stored, perceived, and consumed worldwide, leading to the emergence of new food trends. After reviewing Industry 4.0 technologies (e.g. artificial intelligence, smart sensors, robotics, blockchain, and the Internet of Things) in Part I of this work (Hassoun, Aït-Kaddour, et al. 2022. The fourth industrial revolution in the food industry-Part I: Industry 4.0 technologies. Critical Reviews in Food Science and Nutrition, 1-17.), this complimentary review will focus on emerging food trends (such as fortified and functional foods, additive manufacturing technologies, cultured meat, precision fermentation, and personalized food) and their connection with Industry 4.0 innovations. Implementation of new food trends has been associated with recent advances in Industry 4.0 technologies, enabling a range of new possibilities. The results show several positive food trends that reflect increased awareness of food chain actors of the food-related health and environmental impacts of food systems. Emergence of other food trends and higher consumer interest and engagement in the transition toward sustainable food development and innovative green strategies are expected in the future.

Attitudes towards Freshly Made and Readily Prepared Texture-Modified Foods among Speech-Language Therapists, Dietitians, and Community-Dwelling Older Adults

Texture-modified foods (TMFs) are recommended for patients suffering from swallowing difficulties. Given the increasing aging population, the use of TMFs is on the rise. Research to date has focused on the nutritional value, malnutrition indices and healthcare practices in relation to TMFs, but the perception of these diets from a patient and healthcare practitioner perspective has received less consideration. This study explored how currently available TMFs (including Soft & Bite-Sized, Minced & Moist, and puree) are perceived by key stakeholders. Four types of TMFs were consumer tested: freshly made TMFs following foodservice recipes and three types of readily prepared TMFs (commercially packaged, sous-vide and hydrolysed). The selected samples were tested through five focus groups (including nine dietitians, seven speech-language therapists, and five community-dwelling older adults), which involved a sensory rating using a validated 7-point scale meal assessment tool and a semi-structured focus group discussion. Analysis was conducted using quantitative and qualitative approaches. Soft & Bite-Sized meals had significantly higher palatability ratings than others. Sous-vide meals were most suitable for Soft & Bite-Sized texture, while commercially packaged samples were most appropriate for minced moist and pureed meals. Three main themes emerged through content analysis: (1) palatability of TMFs, (2) perceived challenges with the currently available TMFs and (3) key differences in opinion between stakeholders. Freshly made TMFs were more appealing and tastier, whereas readily prepared (pre-cooked, packaged and require reheating) TMFs had a more consistent texture. The texture of all TMFs requires enhancement, particularly in pureed meals. Developing nutritious and safe TMFs for people with dysphagia requires the promotion of active insight exchange between dietitians and speech-language therapists.

Exploring Meal Provision and Mealtime Challenges for Aged Care Residents Consuming Texture-Modified Diets: A Mixed Methods Study

Dysphagia has become more prevalent with age. Thus, the demand for texture-modified diets (TMDs) has increased. While the nutritional perspectives have been studied, the provision of TMDs and mealtime practice has received less attention. This study aimed to explore the TMD provision and mealtime challenges of residents requiring TMDs in aged care facilities. The study was conducted across five aged care facilities using a mixed methods design involving 14 TMD menu audits by a foodservice dietitian, 15 mealtime observations, and semi-structured interviews with residents and staff (n = 18). TMD menus failed to meet all nutrition requirements and foodservice and clinical standards based on the dietitian NZ foodservice and nutrition audit tool. A content analysis offered three main themes: (1) Foodservice production. Inconsistent quality and meal portions were observed. The variety, choice, and portion size of TMDs required improvement based on the residents’ preferences; (2) Serving procedures. There was a lack of standardisation of meal distribution and feeding assistance; and (3) Dining environment. The dining room set-up varied across facilities, and residents expressed different preferences towards the dining environment. There is a need to improve staff awareness of mealtime consistency and optimise feeding assistance. The dining environment should be individualised to accommodate residents’ psychosocial needs. Standardised policies and continuous training can facilitate quality mealtime implementation.

Sodium bicarbonate reduces the cooked hardness of lotus rhizome via side chain rearrangement and pectin degradation

In this study, 0.1% (W/V) sodium bicarbonate (SB) solution was used to soften lotus rhizome, and the mechanism was characterized by monoclonal antibodies labeling (mAbs) and atomic force microscopy (AFM). The results showed that the cell wall of lotus rhizome was disintegrated under SB treatment. In addition, the mAbs results revealed that low-esterified homogalacturonan (HG) at the tricellular junction was degraded, the rearrangement of Ara and the interaction between Gal and cellulose may be related to the texture changes. Compared with distilled water treatment, SB treatment reduced the relative content of pectin from 34.1% to 19.1% while increased that of cellulose from 65.9% to 80.9%. AFM results revealed that the height of CSF skeleton decreased from about 32 nm to 1.5 nm. These results clearly demonstrate that cooking with 0.1% SB can soften lotus rhizome through degradation of pectin and arrangement of side chains of rhamnogalacturonan-Ⅰ (RG-Ⅰ).

Food for the elderly based on sensory perception: A review

Background

The impairments of physiological functions caused by aging are common problems in the elderly, especially the impairments of sensory perception. Besides, close relationship between food sensory perception and nutritional status also suggests the importance of dietary management for the elderly population. The foods taking sensory perception into account are urgently needed by the elderly.

Scope and approach

This review analyzed sensory perception changes and their effects on food behaviors and nutritional status. Besides, sensory properties essential for aged-foods and acquisition methods, as well as current status of such foods were summarized.

Key findings and conclusions

Soft, smooth and moisty foods were more suitable for the elderly with chewing and swallowing dysfunction, which can be prepared by gelation, enzyme treatment, blade tenderization and other non-thermal technologies. Flavor enhancement/enrichment, irritant addition and packet sauces were recommended to compensate the impairment of chemical sensory. Molds, piping bag and 3D printing were suggested for refining appearance of pureed foods, and improving appetite of the elderly.

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Sensory perception changes of the elderly affect food behaviors and health.

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Soft, smooth, and moisty foods are more suitable for the elderly.

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Gelation and enzyme treatment are applied to modify the texture of aged food.

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Packet sauces may meet the heterogenetic flavor requirements of the elderly.

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Visually attractive food made by 3D printing can increase the appetite of elderly.

Correlation between Instrumental and Sensory Properties of Texture Modified Carrot Puree

This study was undertaken to determine the correlation between instrumental and sensory evaluation on texture modified carrot puree. Texture modified foods (TMF) are prescribed to dysphagia individuals to aid in the oral manipulation and facilitate swallowing of food. There is a lack of correlation between instrumental measurements and sensory attributes on TMF. Understanding this correlation will aid in the formulation of safe foods with desired sensory properties for dysphagia patients. Instrumental measurements of carrot purees were performed by back extrusion method using a texture analyser and the attributes obtained were firmness, consistency, cohesiveness and adhesiveness. Quantitative Descriptive Analysis (QDA) with eight trained panellists was employed to characterize the texture of the carrot puree based on seven sensory attributes: Firmness, viscous, adhesive (mouth), smoothness, adhesive (throat), rate of breakdown, difficulty to swallow. Five thickeners, namely gellan gum, xanthan gum, Suberakaze, UNI-PURE® Dys-sperse instant thickener, ULTRA-SPERSE® M Starch were evaluated against carrot puree without any thickener as control. The correlation results obtained from texture analysis and sensory evaluation were statistically significant (p < 0.05). The firmness attributes from instrumental and sensory results were positively correlated. The consistency parameter was positively correlated to sensory attribute viscous and negatively correlated to smoothness. The sensory attribute rate of breakdown was negatively correlated to instrumental parameter of cohesiveness. Lastly, instrumental adhesiveness was positively correlated to sensory attributes adhesive to mouth and throat, and difficulty to swallow. The correlation results showed a well-designed instrumental technique can be used to understand the impact of thickeners on TMF for dysphagia subjects. This article is protected by copyright. All rights reserved.

Plate waste study among hospitalised patients receiving texture-modified diet

BACKGROUND/OBJECTIVES

While plate waste has been widely investigated in hospitals, there have been minimal studies specific to the texture-modified diet (TMD). This study aims to determine the percentage of plate waste among patients prescribed with TMD and its contributory factors.

SUBJECTS/METHODS

This was a single-centre study conducted in the university hospital on three types of TMD (blended diet, mixed porridge, minced diet) during lunch and dinner meals. Weighing method and visual estimation method assisted by digital photograph were adopted in this study. Face to face interview was carried out to investigate on 1) the food/food service quality factors in terms of patients' satisfaction level towards sensorial quality of food and food services provided and 2) the clinical/external factors including appetite, the provision of oral nutrition support, time taking the diet, the need for feeding assistance and the length of hospital stay.

RESULTS

The mean percentage of overall plate waste of 95 patients receiving TMD was high (47.5%). Blended diet was identified as the most wasted diet (65%) followed by minced diet (56%) and mixed porridge (35%). Satisfaction level among patients was moderate. Patients on TMD in general had higher satisfaction level on the aspect of food service as compared to food quality. Substantial association between sensorial qualities of food and plate waste were varied according to individual TMD type. A multiple linear regression showed that only the satisfaction level toward the aspects of appearance and variety of foods were the predictors of TMD plate waste (R² = 0.254, P < 0.05).

CONCLUSIONS

A significant relationship between the percentage of plate waste and the overall satisfaction level of patients receiving TMD suggests that vigorous strategies are needed to reduce the food waste of TMD which will lead to a better nutritional status and clinical outcomes among the patients.

Formulation engineering of food systems for 3D-printing applications - A review

The efficient development of extrusion-based 3D-printing requires flexibility in both formulation- and process design. This task requires a fundamental understanding of the influence of material rheological properties on the extrusion process. Within this review, a qualitative toolbox for food extrusion is presented which provides guidelines for the formulation and engineering of extrusion processes in general and 3D-printing in particular. The toolbox is based on current knowledge of highly viscous food systems and the influence of individual components on the overall rheology. It includes the efficiency of particle packing, microstructure and the influence of shear rate, as well as the formation of self-supporting structures by gelation of the liquid phase and crowding of particles. Physical laws and semi-empirical equations are discussed to describe the rheology and relate relevant theory to the extrusion process. Practical information is presented, including examples of extrusion and 3D-printing of food and non-food systems. The qualitative extrusion toolbox provides a general framework for the emerging field of extrusion-based 3D-printing of food products. It can be used to identify which specific material and process parameters can be changed and how they may be altered to optimize the 3D-printing process. The general framework will assist researchers, as well as industry.

A review of the enzymatic, physical, and chemical modification techniques of xanthan gum

Xanthan gum (XG), a bacterial polysaccharide has numerous valuable characteristics in the food, biomedical, pharmaceuticals, and agriculture sector. However, XG has also its particular limitations such as its vulnerability to microbial contamination, inadequate mechanical and thermal stability, unusable viscosity, and poor water solubility. Therefore, XG's structure and conformation need to be modified enzymatically, chemically, or physically to improve its optimistic features and decrease the formation of crystals, increase antioxidant ability, and radical scavenging activity. We have found out different means to modify XG and elaborate the importance and significance of the modified structure of XG. In this review, different enzymes are reviewed for XG degradation, which modifies their structure from different points (main chain or side chain). This article also reviews various physical methods (ultrasound, shear, pressure, sonication, annealing, and heat treatments) based on prevailing publications to alter XG conformation and produce low molecular weight (LMW) and less viscous end-product. Moreover, some chemical means are also discussed that result in modified XG through crosslinking, grafting, acetylation, pyruvation, as well as by applying different chemical agents. Overall, the current progress on XG degradation is very auspicious to develop a new molecule with considerable uses, in various industries with future assessments.

Exploring Tools for Designing Dysphagia-Friendly Foods: A Review

Dysphagia is a medical condition that affects normal swallowing. To prevent the risk of aspiration or choking, thickened fluids and texture-modified foods have been used for dysphagia management with the goal of slowing down the flow of liquids and protecting the airway. This article summarizes the available information about the rheological and textural parameters, the characterization of the most-used thickeners and the application of alternative texture modification technologies that are crucial to developing safe dishes for people who suffer from swallowing difficulties. Regarding rheological and textural measurements, fundamental and empirical methods are described.

Formulation and evaluation of bitter taste-masked orally disintegrating tablets of high memantine hydrochloride loaded granules coated with polymer via layering technique

Orally disintegrating tablets (ODTs) improve patient adherence as they can easily disintegrate in the presence of small amount of saliva. However, the bitter taste of the active pharmaceutical ingredient in ODTs reduces patient compliance. The present study aimed to formulate bitter taste-masked ODTs containing high-dose of memantine hydrochloride (MTN) to achieve a balance between bitterness suppression and dissolution rate or disintegration time and mechanical strength. The high MTN-loaded granules were prepared using a fluidized bed granulator. Taste-masking granules coated with the selected polymer were prepared using the layering technique. Three ODTs, composed of granules coated with different polymers, were prepared. The ODT prepared using granules coated with enteric polymers showed the fastest collapse time (>20 s). Dissolution rates of ODTs composed of enteric polymers were reduced by 5 min compared with ODTs composed of non-coated or coated with water-insoluble polymer granules. X-ray computed tomography analysis revealed that low density distribution of ODTs with enteric polymer granules may result in faster disintegration time. Although ODT prepared using enteric polymers had the fastest collapse time, its change in membrane potential caused by adsorption (CPA), corresponding to aftertaste, was the lowest among formulations. This CPA value was lower than the bitterness threshold.

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.