Optimising foods for satiety

Foods that generate strong satiety sensations have obvious ben- efits for weight management. This review builds on the under- standing that a food’s satiating power is dependent on the amount of protein, carbohydrate, fat and fibre it contains by examining evidence that the consumer’s sensory and cognitive appraisal of the food is also important. It is concluded that numerous features of a food product can be manipulated to enhance the consumer’s experience of satiety but the combi- nation of these features will ultimately determine its effect on appetite control. Taking this integrated approach to satiety will optimise the development of high satiety foods

Fluid or fuel? The context of consuming a beverage is important for satiety

Energy-containing beverages have a weak effect on satiety, limited by their fluid characteristics and perhaps because they are not considered ‘food’. This study investigated whether the context of consuming a beverage can influence the satiating power of its nutrients. Eighty participants consumed a lower- (LE, 75 kcal) and higher-energy (HE, 272 kcal) version of a beverage (covertly manipulated within-groups) on two test days, in one of four beverage contexts (between-groups): thin versions of the test-drinks were consumed as a thirst-quenching drink (n = 20), a filling snack (n = 20), or without additional information (n = 20). A fourth group consumed subtly thicker versions of the beverages without additional information (n = 20). Lunch intake 60 minutes later depended on the beverage context and energy content (p = 0.030): participants who consumed the thin beverages without additional information ate a similar amount of lunch after the LE and HE versions (LE = 475 kcal, HE = 464 kcal; p = 0.690) as did those participants who believed the beverages were designed to quench-thirst (LE = 442 kcal, HE = 402 kcal; p = 0.213), despite consuming an additional 197 kcal in the HE beverage. Consuming the beverage as a filling snack led participants to consume less at lunch after the HE beverage compared to the LE version (LE = 506 kcal, HE = 437 kcal; p = 0.025). This effect was also seen when the beverages were subtly thicker, with participants in this group displaying the largest response to the beverage’s energy content, consuming less at lunch after the HE version (LE = 552 kcal, HE = 415 kcal; p<0.001). These data indicate that beliefs about the consequences of consuming a beverage can affect the impact of its nutrients on appetite regulation and provide further evidence that a beverage’s sensory characteristics can limit its satiating power

Transformative and troublesome? Students’ and professional programmers’ perspectives on difficult concepts in programming

Programming skills are an increasingly desirable asset for higher education students across disciplines; however, learning to program continues to be difficult to master for many students. The heterogeneity of student cohorts in most computer science courses makes it challenging to isolate the concepts within programming that are particularly hard for all students to understand (i.e., 'threshold concepts'). As a result, there is a lack of consensus over the threshold concepts that are relevant to those learning programming. This paper draws on a qualitative study using focus groups with undergraduates and professional software developers to identify potential threshold concepts in programming. Data from the focus groups were thematically coded and analyzed using a theoretical framework based on established criteria for threshold concepts. In particular, we focused on concepts that were both troublesome and transformative and included other characteristics such as participants' partiality of understanding. Six potential threshold concepts were identified in the majority of the focus groups, including abstract classes, data structures and designing objects. Further analysis of the data identified additional concepts that may hinder rather than help the learning of these threshold concepts, which we have called 'accidental complexities'

Effects of repeated consumption on sensory-enhanced satiety

Previous research suggests that sensory characteristics of a drink modify the acute satiating effects of its nutrients, with enhanced satiety evident when a high energy drink was thicker and tasted creamier. The present study tested whether this modulation of satiety by sensory context was altered by repeated consumption. Participants (n=48) consumed one of four drinks mid-morning on seven non-consecutive days with satiety responses measured pre-exposure (day 1), post-exposure (day 6) and at a one month follow-up. Drinks combined two levels of energy (lower energy, LE, 326 KJ: higher energy, HE, 1163KJ) with two levels of satiety-predictive sensory characteristics (low-sensory, LS, or enhanced sensory, ES). Test lunch intake 90 minutes after drink consumption depended on both the energy content and sensory characteristics of the drink before exposure, but on energy content alone at post-exposure and the follow-up. The largest change was an increase in test meal intake over time in the LE/LS condition. Effects on intake were reflected in appetite ratings, with rated hunger and expected filling affected by sensory characteristics and energy content pre-exposure, but were largely determined by energy content post exposure and at follow up. In contrast, a measure of expected satiety reflected sensory characteristics regardless of energy content on all three test days. Overall these data suggest that some aspects of the sensory-modulation of satiety are changed by repeated consumption, with covert energy becoming more effective in suppressing appetite over time, but also suggest that these behavioural changes are not readily translated into expectations of satiety

Expectations about satiety and thirst are modified by acute motivational state

Prior research has shown that consumers have clear and measurable expectations about the likely effects of food and drink items on their appetite and thirst, which are acquired with experience and influenced by a product’s taste and texture. What is unclear is whether expression of these expectations also varies with current appetitive state. It is possible that current appetite could increase or decrease the relevance of these expectations for future food choice and magnify a product’s expected impact on appetite. To test this, we contrasted expectations about satiety and thirst for four products consumed two hours after an appetite manipulation at breakfast, achieved through ad libitum access to low-energy drinks only (hunger condition), cereal only but no drinks (thirst condition) or both foods and drinks (sated condition). The test products were two soups and two drinks, with a thicker and thinner version of each product type to act as positive control to ensure sensitivity in detecting differences in expectations. For satiety, the predicted differences between products were seen: soups and thicker products were expected to be more filling and to suppress subsequent hunger more than drinks and thinner products, but these differences were more pronounced in the hunger than thirsty or sated conditions. Being thirsty also enhanced expectations of how much drinks would appease immediate thirst. Overall the data show that expectations were adjusted subtly by a person’s current appetitive state, suggesting that we have mechanisms that highlight the most important features of a product at the time when it may be most beneficial to the consumer

Additive effects of sensory-enhanced satiety and memory for recent eating on appetite

The sensory characteristics of a product have been shown to interact with actual nutrient content to generate satiety. Separately, cued recall of recent eating has also been shown to reduce food intake. Here we explore for the first time how these two effects interact, with the hypothesis that sensory enhancement of satiety might be mediated by more vivid memory of the earlier consumed item. On each of two test sessions, 119 women volunteers consumed a control drink (lemonade) on one morning and then one of two test drinks on the next day 30 min before an ad libitum lunch. The test drinks were equicaloric but one was noticeably thicker and creamier, and expected to generate stronger satiety. Just prior to the test lunch, participants were asked to recall either the test drink (test recall) or the drink from the previous day (control recall). Overall, lunch intake was significantly lower after the thicker and creamier (enhanced sensory ES) than thinner (low sensory: LS) test drink (p < 0.001, η2 = 0.11) regardless of recall condition (p = 0.65, η2 < 0.01), but was significantly lower after the test than control recall condition (p < 0.001, η2 = 0.14). Rated hunger was lower after consuming the ES than LS drink both immediately after consumption (p < 0.001, η2 = 0.11) and prior to the test lunch (p = 0.007, η2 = 0.06), while rated hunger just before lunch tended to be lower after recalling the test than control drink (p = 0.052, η2 = 0.03) regardless of the sensory characteristics (p = 0.27, η2 = 0.01). Overall these data further demonstrate the power of ‘sensory-enhanced satiety’ and cued recall of earlier eating as methods to reduce acute food intake, but suggest these effects operate independently

Does modifying the thick texture and creamy flavour of a drink change portion size selection and intake?

Previous research indicates that a drink's sensory characteristics can influence appetite regulation. Enhancing the thick and creamy sensory characteristics of a drink generated expectations of satiety and improved its actual satiating effects. Expectations about food also play an important role in decisions about intake, in which case enhancing the thick and creamy characteristics of a drink might also result in smaller portion size selection. In the current study forty-eight participants (24 female) completed four test days where they came into the laboratory for a fixed-portion breakfast, returning two hours later for a mid-morning drink, which they could serve themselves and consume as much as they liked. Over the test days, participants consumed an iso-energetic drink in four sensory contexts: thin and low-creamy; thin and high-creamy; thick and low-creamy; thick and high-creamy. Results indicated that participants consumed less of the thick drinks, but that this was only true of the female participants; male participants consumed the same amount of the four drinks regardless of sensory context. The addition of creamy flavour did not affect intake but the thicker drinks were associated with an increase in perceived creaminess. Despite differences in intake, hunger and fullness ratings did not differ across male and female participants and were not affected by the drinks sensory characteristics. The vast majority of participants consumed all of the drink they served themselves indicating that differences in intake reflected portion size decisions. These findings suggest women will select smaller portions of a drink when its sensory characteristics indicate that it will be satiating

Effects of hunger state on flavour pleasantness conditioning at home: flavour-nutrient learning vs. flavour-flavour learning

This study examined acquired liking of flavour preferences through flavour-flavour and flavour-nutrient learning under hungry or sated conditions in a naturalistic setting. Each participant consumed one of three versions of a test drink at home either before lunch or after lunch: minimally sweetened (CONTROL: 3% sucrose, 40kcal), artificially sweetened (3% sucrose 40kcal plus artificial sweeteners ASPARTAME) and sucrose-sweetened (SUCROSE: 9.9% sugar, 132kcal). The test drink was an uncarbonated peach-flavoured iced tea served in visually identical drink cans (330ml). Participants preselected as "sweet likers" evaluated the minimally sweetened flavoured drink (conditioned stimulus, CS) in the same state (hungry or sated) in which they consumed the test drink at home. Overall, liking for the CS flavour increased in participants who consumed the SUCROSE drink, however, this increase in liking was significantly larger when tested and trained hungry than sated, consistent with a flavour-nutrient model. Overall increases in pleasantness for the CS flavour in participants who consumed the SUCROSE drink when sated or the ASPARTAME drink independent of hunger state, suggest that flavour-flavour learning also occurred. These results are discussed in light of current learning models of flavour preference

Narrowing the gap: Literature review

This review supports a research programme that is exploring how technology can narrow the gap for under- and low-achieving learners in secondary schools. Technology can support learning for underachievers by improving results and increasing engagement. Research shows that it can do this by: •monitoring behaviour and targeting learners who need special attention •making the curriculum relevant to learners' everyday experiences •encouraging learners' self-assessment and developing educators' reflective practices •offering targeted online support to learners need it •improving the literacy skills of Non-English Mother Tongue learners •developing learners' executive attention and improving their intelligence scores. Research shows that many different approaches using technology are effective. For instance, playing electronic games can encourage learners to practice skills such as language development. Games can also engage learners with special educational needs, such as ADHD. In one study, boys aged 9-11 with ADHD played a computer driving game. They were more engaged and had a tiny dropout rate compared to boys with ADHD who did not play. Using presentation software in the classroom can also produce results. Researchers found that learners rate educators who use this technology more highly than educators who don't

Using problem and project-based learning to integrate sustainability in engineering education

Engineering graduates are increasingly required to implement sustainability focussed initiatives within industry, alongside enhanced expectations from professional bodies and the UK specification (UK-SPEC) for engineers (Engineering Council, 2024). However, a recent study of UK Higher Education institutions highlighted that only a handful have implemented Education for Sustainable Development (ESD) into their curricula in a systemic manner (Fiselier et al., 2018), which suggests many engineering institutions still need support in this area. Sustainability topics need to be embedded within engineering education, so that each discipline-specific engineering problem is explored within Problem and Practice Based Learning (PBL) from a technical, economic, ethical, and sustainability perspective. Drawing from UWE Bristol’s journey of Education for Sustainable Development implementation using PBL, key recommendations are outlined in this Toolkit Guide created by the Engineering Professors' Council