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The flavour of food is one of the key factors determining food quality and acceptance. When food is eaten, flavour compounds are released at different rates, depending on the physical properties of the molecules themselves and on the physical and chemical properties of the food matrix. When foods are reformulated to meet dietary goals (e.g. low sugar or fat, high fibre) there is a change in flavour release properties which adversely affects the perceived flavour. Flavour analysis has generally ignored the temporal aspects of flavour release but this parameter may help explain subtle differences in flavour perception. Methods for measuring sensory changes with time (time intensity analysis) are well established but methods for measuring the flavour volatiles delivered to the olfactory receptors have recently developed to the stage where detection at the ug/kg (ppb) level is achievable. Results from these measurements have been used to study flavour release from a range of foods. One application of this technique is to determine the differences in flavour release between regular and low‐fat foods. The information obtained can be used to reformulate flavours in a systematic manner to improve the flavour of low‐fat products.

Dietary guidelines consistently advocate the reduction of fat in the diet and the food industry has responded by introducing a vast range of reduced fat foods on to the market. However, reduced fat diets are difficult for people to maintain. Nutrition education is at a critical crossroads, such that consumers have received the message to reduce fat in the diet, but are unable or unwilling to comply with this information so that overall health status can be improved. Better understanding of the factors that influence fat intake will help to explain why dietary change is so difficult to sustain. Sensory studies and focus group discussions were conducted with consumers to assess their perceptions, acceptance and preferences for reduced fat products. The results implied that consumers associate reduced fat foods with inferior sensory properties and perceive them with a degree of scepticism and mistrust.

The aim of this study was to compare the organoleptic attributes and meltability of selected, commercial dairy-free imitation cheeses (DFICs) with those of their dairy counterparts to thus determine whether commercial DFIC needs to be further developed.

Market research was conducted to determine the availability of DFICs in the United Kingdom (UK) and thus select the varieties to assess. Mild cheddar was chosen for its popularity wide availability in the United Kingdom and Italian-style hard cheese for its complex organoleptic profile. The organoleptic attributes and melting properties of the chosen DFIC products were assessed by using descriptive sensory evaluation and their meltability was assessed using the Arnott test, respectively.

109 different DFICs were found; most of them (74%) presented coconut oil as their primary ingredient. None of the assessed DFICs assessed could mimic the organoleptic attributes of their dairy counterparts accurately; however, one of the non-dairy mild cheddar samples was regarded as potentially acceptable by the assessors of the sensory evaluation assessors. Nonetheless, the meltability of this sample was significantly lower than that of mild cheddar cheese.

The findings indicate that, to obtain products that can mimic the organoleptic attributes and meltability of cheese more accurately, further development is required for the DFIC varieties assessed.

No academic publications have explored and investigated commercial DFICs with similar ingredients to those found in commercial DFICs; the commercial importance of these products may augment in the short term owing to the reported growth in the number of vegan individuals in the UK and in Europe.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

The “chiralisation” of Euclidean polygonal tessellations is a novel, recent method which has been used to design new auxetic metamaterials with complex topologies and improved geometric versatility over traditional chiral honeycombs. This paper aims to design and manufacture chiral honeycombs representative of four distinct classes of 2D Euclidean tessellations with hexagonal rotational symmetry using fused-deposition additive manufacturing and experimentally analysed the mechanical properties and failure modes of these metamaterials.

Finite Element simulations were also used to study the high-strain compressive performance of these systems under both periodic boundary conditions and realistic, finite conditions. Experimental uniaxial compressive loading tests were applied to additively manufactured prototypes and digital image correlation was used to measure the Poisson’s ratio and analyse the deformation behaviour of these systems.

The results obtained demonstrate that these systems have the ability to exhibit a wide range of Poisson’s ratios (positive, quasi-zero and negative values) and stiffnesses as well as unusual failure modes characterised by a sequential layer-by-layer collapse of specific, non-adjacent ligaments. These findings provide useful insights on the mechanical properties and deformation behaviours of this new class of metamaterials and indicate that these chiral honeycombs could potentially possess anomalous characteristics which are not commonly found in traditional chiral metamaterials based on regular monohedral tilings.

To the best of the authors’ knowledge, the authors have analysed for the first time the high strain behaviour and failure modes of chiral metamaterials based on Euclidean multi-polygonal tessellations.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Notes of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

The Management Systems Training Council was a co‐operative organization which was developed in the UK in the 1970s to support training and development activity in organization and methods and related topics. Charts the history of the Council from its origins in the 1950s until its demise in 1994, and highlights its achievements using comments from members of the Council. Also relates the work of the Council to more recent developments in quality and re‐engineering.

Fused filament fabrication (FFF) is a widely used 3D printing technique for the fabrication of mechanical metamaterials with intricate geometries. Gradient strategy is applied to geometric parameters of gradient star re-entrant hybrid auxetic (GSRA) structure. Deformation behaviour is studied under compressive loading. The purpose of this study is to investigate the influence of gradient geometric parameters on mechanical properties, namely, specific strength (SS), specific modulus (SM) and specific energy absorption (SEA).

Response surface methodology (RSM) is implemented for the design of experiments of gradient geometric parameters to minimize the number of experimental tests. Acrylonitrile butadiene styrene material is used for the fabrication of GSRA structures by FFF technique. The best set of gradient parameters has been optimized maximizing all three responses using RSM and artificial neural network optimization technique.

During compressive testing, row-wise deformation is observed with two-stage plateau regions, which results in increase in SEA of the structure. Furthermore, based on analysis of variance and 3D response plots, it is found that height gradient is the most influencing gradient geometric parameter on SS and SM, whereas the wall thickness gradient has maximum influence on SEA. Meanwhile, the interaction effect of wall thickness gradient and height gradient has maximum influence on SS, SM and SEA.

This study of applying gradient strategy to geometric parameters is limited to GSRA structure under compressive loading. In addition, findings are valid within the selected range of gradient geometric parameters. These findings are useful for the selection of gradient geometric parameters to maximize SS, SM and SEA of GSRA structure simultaneously. These outcomes pave the way for designing light-weight gradient hybrid auxetic structures in the field of construction, aerospace, automobile and biomedical engineering.

Limited experimental study is available on investigating the influence of gradient geometric parameters on mechanical properties, namely, SS, SM and SEA, and deformation behaviours of hybrid auxetic structures. This study directly addresses the above research gaps.

Auxetic sandwich structures are gaining attention because of the negative Poisson’s ratio effect offered by these structures. Re-entrant core was one configuration of the auxetic structures. There is a growing concern about the design and behavior of re-entrant cores in aerospace, marine and protection applications. Several researchers proposed various designs of re-entrant core sandwiches with various materials. The purpose of this study is to review the most recent advances in re-entrant core sandwich structures. This review serves as a guide for researchers conducting further research in this wide field of study.

The re-entrant core sandwich structures were reviewed in terms of their design improvements, impact and quasi-static crushing responses. Several design improvements were reviewed including 2D cell, 3D cell, gradient, hierarchical and hybrid configurations. Some common applications of the re-entrant core sandwiches were given at the end of this paper with suggestions for future developments in this field.

Generally, the re-entrant configuration showed improved energy absorption and impact response among auxetic structures. The main manufacturing method for re-entrant core manufacturing was additive manufacturing. The negative Poisson’s ratio effect of the re-entrant core provided a wide area of research.

Generally, re-entrant cores were mentioned in the review articles as part of other auxetic structures. However, in this review, the focus was solely made on the re-entrant core sandwiches with their mechanics.

This study aims to determine the threshold of salt taste recognition and to evaluate differences by sex, age and body mass index (BMI) among a sample of Moroccan population.

A simple-blind experimental study was conducted among 201 healthy subjects to determine the threshold of salt taste recognition and to evaluate differences by sex, age and BMI among a sample of Moroccan population. The threshold of salt taste recognition was determined based on the validated the three alternatives forced choice method. A total of 11 prepared solutions of sodium chloride at different concentrations ranging from 0–500 mmol/L were used.

The average of the total population was 14.6 ± 10.9 mmol/L. And, 84% of the total population recognized the salt taste at the concentration of 15 mmol/L. Women participants detected the salt taste at a lower rate (53% versus 38% at 8 mmol/L, p = 0.02, in women and men, respectively). The mean values of the threshold among women was significantly lower (12.6 ± 8.1 mmol/L) compared to men (16.7 ± 12.8 mmol/L), p < 0.001. No statistical difference was obtained among either age groups or BMI categories.

The present study showed that the average threshold of salt taste recognition is high, and that it is even higher in men compared to women. At a community level, a progressive reduction of salt in food items is recommended.