Taste enhancement of savoury food aiming to increase acceptance by an elderly cohort

Abstract

Diminished sensory ability, and specifically smell and taste deterioration caused by ageing or due to medication and illness, is one common factor which contributes to malnutrition within older adults (1) . However, it has been shown from previous studies that flavour enhancement of food using monosodium glutamate and/or added flavours resulted in increased food intake among sick and healthy elderly individuals (2) .The aim of this study was to increase the liking of food for older adults by enhancing the savoury (umami) characteristics. The novelty of this project lies in the optimisation of naturally occurring tastants at levels preferred by an elderly cohort. Initially, a variety of natural ingredients, such as fermented soy products (soy sauce and miso paste), yeast extract, shiitake mushroom extract and mycoscent (a natural flavouring which is a byproduct of mycoprotein) were used in order to increase the umami taste of minced meat samples. These samples were then offered to a group of older volunteers (n 32, age 62-83, mean 73) and they were asked to score their liking. There was no significant difference in consumer mean liking between the products, nor any correlation between liking and umami intensity.To further intensify the umami taste of the minced meat samples, combinations of the soy sauce (Kikkoman) with mycoscent or shiitake extract or a commercial concentrated tomato extract (Santé, Lycored Ltd.) were prepared. The minced meat samples were evaluated by a trained analytical sensory panel (n 10) using quantitative descriptive profiling and, after appropriate ethics approval, by older volunteers (n 36, age 62-87, mean 71), who scored liking using a nine-point hedonic scale. Mean values with the same superscript letters were not significantly different (Nemenyi's procedure for non-parametric data; P < 0.05).From the sensory evaluation of the samples it was found that there were significant differences (P < 0.05) in thirty-seven attributes among which the most important, as seen in Fig. 1, are umami taste, sweetness and bitterness, and flavour attributes such as beef stock, yeast extract and shiitake mushroom flavour. From the liking results the soy sauce plus tomato extract sample had the highest mean liking score, but there was no significant difference in mean liking. Considering the positive and negative comments made by the volunteers about the samples, the sensory profile and the liking scores, the soy sauce plus tomato extract sample will be taken forward to the next part of the study which includes the taste enhancement of a real food (cottage pie) served in the hospital.Study was sponsored by Research into Ageing.

Ageing and taste

“…Seventeen studies found taste-identification thresholds to increase with age, although one study reported only a weak relationship between age and taste strip results (52) . Only one study found no significant difference between age groups (53) ; however, their older group was younger than in all other studies reported in this review (age [51][52][53][54][55][56][57][58][59][60][61][62][63][64][65], and therefore outside of our inclusion criteria. (27) 18 34 37 65-78 55-65 ME NaCl, SU (6) NaCl P < 0 .…”

“…While deterioration in salt perception should not be compensated for by the addition of extra salt in food for elderly people who may already be at risk of hypertension, CVD or hypernatraemia, authors have suggested that increased levels of umami tastants can improve liking and consumption of foods by older adults. Although this has typically been achieved through the direct addition of monosodium glutamate (2) , it can also be achieved through the use of natural ingredients rich in umami taste compounds (65) . Sensory decline is a generic process and happens to everyone, yet several factors can influence the extent of this sensory decline.…”