Protein and sustainability

Protein and food choice

Food composition is known to influence dietary behaviour. In particular, foodenergy-density is found to associated with palatability and food choice (Brunstrom, Drake, Forde, & Rogers, 2018. However, modelling overall energy content masks subtle differences in the value that is placed on individual macronutrients. Evidence for macronutrient-specific appetites (especially for protein) is mixed (Berthoud, 2012; Carreiro et al., 2016).

Previously, Jeff Brunstrom worked on an BBSRC-funded project,Proteinfor Life, which was led by Newcastle University, with academic collaborators from Sheffield, Liverpool, and Aberdeen,with input from seven industry stakeholder partners. Our workassessed factors related to protein intake during three different life stages: mid-life (40-54 years), younger old (55-69 years), and older old (70 + years).The decline of muscle mass/strength is a key component of healthy ageing and can have a major impact on quality of life. Increasing protein intake at all stages of the life course may help to reduce the rate of muscle decline and the onset of associated health conditions. However, there is a lack of understanding around the social, demographic, and psychological drivers of protein intake and how this changes as we age. In the NBU, we developed predictive models at food choice, and used them to expose subtle differences in ‘food-choice architecture.’We showed that people value protein more than other macronutrients (when compared calorie for calorie) and that this ‘protein valuation’ is a good predictor of muscle mass in an older population.

Currently, Jeff Brunstrom and Annika Flynn are collaborating with Dr Olga Davidenko, Dr Nicolas Darcel, and Prof Suzanne Higgs to assess the extent to which the protein content of food can be learned and whether this ‘flavour-nutrient leaning’ can influence people’s food choices.

Finally, one of our PhD students, Eleanor Underhill (supervised by Jeff Brunstrom), is building on this work to look at whether evidence for ‘protein learning’ can inform our understanding of how to transition to more sustainable sources of dietary protein. Her work is funded by the ESRC-SWDTP.

Example publications:

Buckley, C. M., Austin, S., Corfe, B. M., Green, M. A., Johnstone, A. M., Stevenson, E. J., . . . Brunstrom, J. M. (2019). Protein Valuation in Food Choice Is Positively Associated with Lean Mass in Older Adults. J Nutr.
Brunstrom, J. M., Drake, A. C. L., Forde, C. G., & Rogers, P. J. (2018). Undervalued and ignored: Are humans poorly adapted to energy-dense foods?Appetite, 120, 589-595.

Disgust and protein acceptability

A shift towards certain sources of sustainable protein (e.g., cultured meat, edible insects) is likely to face considerable resistance from consumers(Wellesley, Happer, & Froggatt, 2015). Some people find these ingredients disgusting and the NBU is exploring interventions to reduce this ‘disgust response’.

PhD student Maya Gumussoy (supervised by Peter Rogers) has been developing and refining implicit methods to measure food disgust. Measures include; tactile sensitivity and heart-rate variability (physiological measures), facial expression categorisation (emotional state can affect perception of expressions) and latency to eat (time between experimenter’s verbal instruction to consume food and the participant consuming the food). Maya is using these methods to evaluate the impact of various interventions to reduce disgust towards insect-containing food. Her work suggests thatstudies should focus on interventions that enhance familiarity with these novel ingredients, rather than education-based interventions, such as messaging about sustainability and health.

Example publications:

Gumussoy, M., Macmillan, C., Bryant, S., Hunt, D. F., & Rogers, P. J. (2020). Desire to eat and intake of ‘insect’ containing food is increased by a written passage: the potential role of familiarity in the amelioration of novel food disgust. Appetite, 105088.

Sustainable sources of protein

Ph.D. student Yeliz Vural(supervised by Peter Rogers) has been exploring other meat alternatives, such as cultured meat and plant-based substitutes. Yeliz is investigating consumer taste expectations (e.g., pleasantness, healthiness, and disgust) to explore how consumers think and feel about these products. Her work aims to develop strategies that reduce our meat consumption.

Cultured meat is a meat substitute that is produced from animal stem cells (muscle sample). The potential to produce meat with less land, energy, and water is considerable. Using quantitative and qualitative methods, Yeliz is conducting studies to explore what people think and feel about cultured meat. A recent project sought to compare responses to cultured meat in ‘regular’ meat eaters and non-meat eaters. In our studies, we use ‘slaughter-free meat’ to describe cultured meat as we find this definition more politically correct than calling it as ‘clean meat’ or ‘lab-grown meat’.