Insights into rational design of plant based foods to improve management of dysphagia

Abstract

Normal swallowing is a complex process which requires sufficient mastication and lubrication of the food to transport the bolus from the mouth to the pharynx. In people suffering from dysphagia this process is not well coordinated and they often have difficulty in transporting food and water from the mouth to the stomach, which can lead to choking or aspiration. Modification of food texture by mincing or pureeing normal food is used to prevent these complications; however inconsistencies in texture can affect the consumption of these foods. Hence, malnutrition, dehydration and aspiration pneumonia, are a common problem with dysphagia sufferers.Using green peas as a model food system, this project investigated the effect of three method of comminution -mincing, pureeing and freeze-fracturing (processing whilst frozen) -on the macro and microstructure of the peas and its impact on rheological behaviour and sensory perception.Comminution of peas resulted in a particulated soft solid with hierarchical structures with broad range of particle sizes and shapes i.e. from large clusters of cells (5 mm) to starch granules (10 µm) which were released from broken cells. These pea particles were suspended in serum released during cellular structure breakdown. The high concentration, broad particle size distributions, variations in morphology and deformability of particles made this system complex and challenging to measure. Vane geometry was used to evaluate the rheological behaviour of comminuted peas, as it enabled accurate measurement of dispersions containing large particles without altering the product structure and it also eliminated any wall slip effects. The effect of pea variety, particle size distribution and amount of serum or added water on rheological behaviour was studied.Results demonstrated that comminuted peas were characteristically solid-like with higher elastic than viscous modulus (G´ > G˝). They also exhibited a yield stress which is an important parameter in these systems as it is a good indicator of the amount of effort required to initiate flow during oral processing. Minced peas with over 50% of the particle >1 mm in size had broader size distribution, which packed better than narrower distributions of pureed peas, resulting in higher G´ and yield stress. Changing the particle size distributions by systemically increasing the percentage of minced peas in a mince/puree blend also increased G´ and yield stress. This indicated that particle size distribution can be used to modify flow behaviour, while keeping the solids content the same.Diluting minced and pureed peas with incremental amounts of water showed that in such concentrated systems, small changes in solid to liquid ratio had a considerable impact on G´ and yield stress, as small increments in the liquid phase decreased G´ and yield stress dramatically. The variety of pea did not impact on the particle size distribution, but it affected the amount of serum released and particle firmness. These findings showed that particle concentratio...

Bolus rheology and ease of swallowing of particulated semi-solid foods as evaluated by an elderly panel

“…The list of sensory attributes was prepared based on previous studies. [16][17][18][19] During the familiarisation session, the protocol and the different sensory attributes were explained and discussed with the panellists to ensure that they were familiar with the samples and the vocabulary used to define the sensory attributes. Reference samples were also evaluated to understand the scales for rating the attributes.…”

Validating the textural characteristics of soft fish‐based paste through International Dysphagia Diet Standardisation Initiative recommended tests

“…There were two main purposes of water addition. One was to assist with the preparation process of fish paste as the colloid mill cannot handle excessively thick samples (Sharma, Chakkaravarthi, Singh, & Subramanian, 2008); the other one was to meet the needs of people with dysphagia to take in many nutrients at once, such as water, protein, and fat, so that the paste is moist and nutritious (Steele et al, 2015; Tobin, 2014). According to IDDSI framework, fish paste produced by grinding fish‐water mixture should be at Level 4 (like pureed meat, thick cereal, peas, and tender mince), which needed to be confirmed by the spoon tilt test and fork drip test.…”

“…Swallowing is a complex neuromuscular activity, but some dysphagia patients' pharyngeal activity is weak that makes it difficult for them to transport food and water from the mouth to the stomach (Duffy, 2018). Dysphagia can be managed through texture‐modified foods and thickened liquid to make swallowing safer providing optimized nutrition and hydration (Steele et al, 2015; Tobin, 2014). Texture modification aims to control the relationship between formation and subsequent manipulation of the bolus with deglutition, often aiming to make liquids flow more slowly, foods flow more easily, or heighten the perception of the bolus and limit the risk of choking (Hanson, 2016; Sukkar, Maggi, Travalca Cupillo, & Ruggiero, 2018).…”