Consumers’ attitudes towards alternatives to conventional meat products: Expectations about taste and satisfaction, and the role of disgust

The livestock sector has environmental, health, and animal welfare impacts. This UK-based, quantitative study aimed to elucidate consumers' valuation of alternatives to conventional meat products. In an online study, 151 meat eaters and 44 non-meat eaters were shown pictures of meat, dairy, and bakery products, including beef burger, cheese sandwich and blueberry muffin. Each product was evaluated with three different labels (e.g., 'conventional', 'plant-based' and 'cultured' for beef burger). Participants rated expected taste pleasantness, fullness, satisfaction, healthiness, disgust and willingness-to-pay for each product/label combination. The results obtained demonstrate that alternatives to conventional meat products overall are acceptable to both meat and non-meat eaters. Although meat eaters' expected plant-based meat alternatives to be less satisfying, due to lower expected taste pleasantness and fillingness (Cohen's d = 0.14 to 0.63), they perceived the plant-based alternatives to be more healthy (d ≥ 1.18). Cultured meat products were perceived by meat eaters to be equally or more healthy, but more disgusting (d ≥ 0.41), than conventional meat products. These results suggest there is an opportunity to promote (motivate) acceptance of alternatives to conventional meat products based on their perceived healthiness, to at least partly balance reduced expected taste pleasantness and other negative attributes (i.e., barriers).


Background and previous studies
Current meat and dairy production models coupled with the global scale of meat consumption are considered to be key contributors to climate change (Smil, 2002;Steinfeld et al., 2006). The livestock sector solely releases approximately 14.5% of the all human-generated greenhouse gas emissions (Gerber et al., 2013) and accounts for a large proportion of land and water use (Aleksandrowicz, Green, Joy, Smith, & Haines, 2016;Poore & Nemecek, 2018) which leads to deforestation and eutrophication (Berardy et al., 2020). High meat and dairy intake also pose a threat to human health (Sadler, 2004;Willett et al., 2019). High meat intake (especially of red and processed meats) in particular, is associated with increased risk of non-communicable diseases such as cancer, type-2 diabetes, and coronary heart disease (Budreviciute et al., 2020;Willett et al., 2019). Meat and dairy production also raises concerns regarding animal welfare (Bryant, 2019). Accordingly, reducing conventional meat and dairy consumption is highly recommended by Non-Governmental Organisations (NGOs), governmental bodies and food and environment scientists (Aiking & de Boer, 2020;Garnett, 2011;Public Health England, 2016;Scarborough et al., 2014;Smil, 2002;Wellesley, Happer, & Froggatt, 2015;Willett et al., 2019).
Studies to date have shown that reducing meat and dairy intake, compensating via a predominantly plant-based diet (consisting of cereals, vegetables, fruits and minimal or no consumption of animalderived products) significantly reduces environmental burden (Aleksandrowicz et al., 2016;Westhoek et al., 2014) and protects against health-related risk factors (Benatar & Stewart, 2018;Sadler, 2004). On the other hand, demand for animal protein, specifically for red meat, is steadily growing in middle-income countries (Godfray et al., 2018;Wellesley et al., 2015). In 'affluent countries' such as the United Kingdom, the diet depends heavily on animal-derived protein (Aiking & de Boer, 2020), including processed red meat (Ekmekcioglu et al., 2018).
The demand for conventional meat and meat products have been linked to their perceived nutritional value and desirable sensory characteristics (i.e., taste, texture, etc.) (Graham & Abrahamse, 2017;Slade, 2018). For example, conventional meat is considered as a 'key source of protein and energy' (Leroy et al., 2022) and rich in zinc, iron, and vitamin B12 that are considered to be 'irreplaceable' (Leroy et al., 2022). Meat is also addressed as being a traditional food; a symbol of vitality, strength (Leroy & Praet, 2015) and prestige in many cultures (Smil, 2002). In addition, meat eating behaviour is highlighted as an 'automatic' behaviour for some meat consumers (Hielkema, Onwezen, & Reinders, 2022). Together, this literature suggests that conventional meat is highly valued, and that many meat consumers would resist significantly reducing their consumption of meat (Graça, Calheiros, & Oliveira, 2015;Wellesley et al., 2015). Nonetheless, it has been argued that good quality alternatives to conventional meat (including plant-based products and cultured meat) and dairy products can provide a means for decreasing consumption of animal-sourced products, whilst at the same time meeting nutritional requirements and achieving sustainability goals (Michel, Hartmann, & Siegrist, 2021).
Growing interest in meat free diets and advancements in technology have allowed industry to introduce a range of high-quality plant-based meat alternatives (Joshi & Kumar, 2015;Sadler, 2004). Plant-based meat alternatives are meat-free products based on vegetable protein such as soy, wheat protein and fungi (Hoek et al., 2011). Substantially, these products aim to mimic the sensory qualities (taste, smell, flavour, texture) of conventional meat (Joshi & Kumar, 2015;Tso, Lim, & Forde, 2021).
Cultured meat, on the other hand, is a more recent alternative to conventional meat (introduced in 2013), that is defined as an animal and planet-friendly way of producing ('growing') meat in a laboratory/factory environment from stem cells taken from animals (Post, 2012). Cultured meat is not widely available, yet it has created significant interest towards cellular agriculture among food scientists (Bryant & Barnett, 2018). Therefore, its acceptance is still an important question. Studies investigating acceptance of cultured meat, in general, have concluded that consumers are not open to consume cultured meat (Sharma, Thind, & Kaur, 2015;Siegrist & Sutterlin, 2017;Verbeke et al., 2015). Specifically, consumers were found to attribute negative associations and emotions to cultured meat such as 'unnatural', 'artificial' and disgusting (Bryant & Barnett, 2018;Verbeke et al., 2015). Furthermore, in a recent study cultured meat products were perceived by consumers as being more expensive, more caloric, and less sustainable compared to their conventional meat counterparts, as well as compared to plant-based meat alternatives (Possidónio, Prada, Graça, & Piazza, 2021). By contrast, it is suggested that mass production of cultured meat will have significantly lower environmental impact via associated GHG emissions and energy, water, and land use than production of conventional meat (Tuomisto & Teixeira de Mattos, 2011). Post (2012), the inventor of cultured meat, also notes that it is possible to make cultured meat healthier by modifying its composition, such as decreasing its saturated fat content.
Attitudes are psychological constructs (McEachern & Schröder, 2002) and, in relation to the present research, are key determinants to accepting or rejecting alternatives to conventional meat products (Onwezen, Bouwman, Reinders, & Dagevos, 2021). Although, there are previous published studies investigating consumers' attitudes towards plant-based meat alternatives and cultured meat, there remain important gaps in the literature addressing this subject.
First, a recent systematic review by Onwezen et al. (2021) shows that most of the previous research on alternatives to conventional meat has focused on insects as alternative protein sources (fifty-eight studies in total reported). By contrast, there are fewer studies investigating consumers' attitudes towards plant-based meat alternatives (nine studies) and cultured meat (sixteen studies), especially in the United Kingdom context (five studies in total, including other alternatives such as insects). Therefore, this study will contribute to the existing literature by providing more information about what UK consumers think and feel about plant-based meat alternatives and cultured meat.
Second, studies investigating consumers' attitudes towards alternatives to conventional meat have, in general, provided non-neutral descriptions of products, especially for cultured meat. Non-neutral descriptions for alternatives to conventional meat, especially for cultured meat would likely to lead consumers to give biased responses (Mancini & Antonioli, 2019). For example, framing cultured meat as 'clean meat' or 'animal-free meat' was highlighted to significantly increase acceptance of cultured meat compared to framing cultured meat as 'lab-grown meat' (Bryant & Barnett, 2019). It is also questionable whether such terms would be permitted commercially. Therefore, we took care to prepare realistic, factual descriptions of the food products in question.
Third, another novel aspect of the present study is that attitudes of both meat eaters and non-meat eaters towards conventional meat and alternatives to conventional meat were measured under the same experimental design. This approach is important, since these different consumers potentially have a choice of various alternatives to conventional meat.
Fourth, the present study aimed to explicitly examine disgust as 'a potential barrier' in acceptance of plant-based meat alternatives and cultured meat compared to conventional meat in meat eaters and nonmeat eaters. Disgust is defined as a basic emotion which leads to a hard to overcome rejection of foods perceived as, for example, inappropriate or potentially harmful or contaminated (Rozin & Fallon, 1987), and previous studies have highlighted disgust as a significant barrier in accepting plant-based meat alternatives (e.g., in the USA, but not in India and China) (Bryant, Szejda, Parekh, Deshpande, & Tse, 2019) and cultured meat Verbeke et al., 2015). Therefore, understanding the contribution of disgust in relation to different alternatives to conventional meat and different consumer groups is important in targeting food-based interventions to promote sustainable, but novel, alternatives to conventional meat.
Fifth, the final contribution of the present research was to complement previous quantitative studies by explicitly quantifying the effect sizes of drivers (health) and barriers (taste pleasantness and disgust) in the acceptance of alternatives to conventional meat.

Hypotheses
This study aims to test following hypotheses. The primary hypothesis of this study was that meat eaters would overall value the conventional meat products more highly than the alternatives to conventional meat. We also predicted that cultured, and possibly plant-based meat alternatives, would be rated as more disgusting than their conventional counterparts. For non-meat eaters, we predicted that they would value plant-based meat alternatives more than the conventional meat products. We did not set a specific hypothesis for the evaluation of cultured meat vs. conventional meat products for non-meat eaters since the primary focus of this study was on meat eaters' attitudes towards plant-based meat alternatives and cultured meat. However, we were interested in non-meat eaters' potential acceptance of cultured meat as an alternative to conventional meat.
We also included non-meat products ('filler items' such as dairy and bakery products) as comparators in the study. We hypothesised that the 'differences in attitudes' (relative effect sizes) towards alternatives to animal products (e.g., cultured, plant-based and vegan dairy products) would be larger than the differences in attitudes towards other product alternatives (e.g., organic dairy products and low-fat or low-sugar bakery/confectionary products), which are more familiar and involve smaller differences in product ingredients. For example, we predicted that the effect size of healthiness ratings of a plant-based burger vs. conventional beef burger would be greater than the effect size of healthiness ratings of an organic vs. non-organic cheese sandwich.
A further aspect of this study was to determine (1) predictors of meal satisfaction, and (2) predictors of the overall value of the food product (measured by a 'willingness to pay' rating). Based on previous research (Rogers, Drumgoole, Quinlan, & Thompson, 2021), we hypothesised that satisfaction would be predicted by expected taste pleasantness (i.e., food liking) and fillingness of the food, and in turn that willingness to pay would be predicted by satisfaction, healthiness, and disgust.

Methods
This was an online survey conducted according to design shown in Table 1 and labels accompanied the test foods in Table 2. The test foods were not tasted; therefore, evaluations (ratings) would have been made on the information given, together participants' existing knowledge of similar products, including possible future products (i.e., cultured meat products). This then models evaluation at the point of choice or purchase, rather than at the point of consumption. Evaluation of the products included expected/anticipated liking, satisfaction, and healthiness, which likely combine to influence choice.

Participants
To the authors' knowledge, a similar quantitative online study on alternatives to conventional meat was not available at the time of the survey design (December 2018). Therefore, we recruited 100 participants per study arm (200 in total, section 2.2) on the assumption of small to medium effect sizes for 80% power at α = 0.05 (two-tail). Participants were volunteer community members (N = 120 from public and N = 80 University of Bristol students), with inclusion criteria of aged ≥18 years, being fluent in English, not having a significant food allergy or food intolerance, living in the UK, being willing to abstain from eating 3 h before the study and being willing to not to consume anything for the duration of the study (30 min). They were recruited through University of Bristol, School of Psychological Science Experimental Hours Scheme, and the Nutrition and Behaviour Unit's database of approximately 1250 public volunteers. The study was advertised as 'The UK Foods Study 1' and the participants were informed that 'the study aims to understand how people eat and appreciate new foods' so as to conceal the full purpose of the study. Participants from the public database were offered a chance to win one of two Amazon gift vouchers each with value of £50 in exchange for their participation. Students were awarded 0.5 course credit for their time through an 'experimental hours scheme'.
Ethical approval was granted by the University of Bristol Faculty of Life Sciences Human Research Ethics Committee (ID): 28031983964.

Study design
The study was conducted online using the survey software 'Qualtrics XM' (Provo, UT). The design comprised two study arms as outlined in Table 1. One hundred participants were randomised to each study arm. Randomisation was done by the lead researcher (YV) using an online randomisation tool (randomizer.org accessed August 1st, 2019).
For each of the six conventional foods there were two alternative foods (labels). For example, the alternatives for beef burger, were cultured beef burger (Study arm 1) and plant-based burger (Study arm 2). Each food was depicted in a photo accompanied by the relevant food labels, comprising a food name and description (shown in Table 2). All photos were in fact of conventional food products (meat beef burger, dairy cheese sandwich, etc), although each was photographed in two versions differing slightly in appearance. For example, one version accompanied the conventional label, and the other accompanied an alternative label. The purpose of this was to make participants believe that the conventional food and its alternative food (e.g., conventional a One hundred participants were assigned randomly to each study arm. Within each arm, participants evaluated the six conventional and six alternative foods listed in the table. On each of these 12 food trials, participants were shown a photo of the food (the photo was always of the conventional version of the food in question), accompanied by the label (name and brief description) detailed in Table 2. On each trial, participants evaluated the food for expected taste pleasantness, fullness/fillingness, satisfaction, healthiness, willingness to pay, and disgust (details shown in Table 3).

Table 2
The labels accompanying the test foods.

Food name Food description
Conventional beef burger This beef burger is produced from cows bred and reared in the UK. This is conventionally farmed meat.

Cultured beef burger
This cultured beef burger is made from meat grown in a UK factory from a small sample of cow cells. Cultured meat is produced without animal slaughter.

Plant-based burger
This plant-based burger is made from vegetable products from crops grown in the UK. This burger contains no animal products.

Conventional chicken nuggets
These chicken nuggets are produced from chickens bred and reared in the UK. This is conventionally farmed chicken. Cultured chicken nuggets These cultured chicken nuggets are produced from chicken meat grown in a UK factory from a small sample of chicken cells. Cultured meat is made without animal slaughter.

Plant-based nuggets
These plant-based nuggets are made from vegetable products from crops grown in the UK. This burger contains no animal products.

Conventional cheese sandwich
The cheese in this sandwich is made from milk from cows bred and reared in the UK. This is conventionally produced cheese. Vegan cheese sandwich The cheese in this sandwich is non-dairy, made from vegetable products from crops grown in the UK. This cheese contains no animal products. a Organic cheese sandwich The cheese in this sandwich is made from organic milk produced from cows bred and reared in the UK.
Organic farming aims to produce food using natural substances and processes.

Conventional ice cream
This ice cream is made from milk from cows bred and reared in the UK. This is conventionally produced ice cream.

Vegan ice cream
This ice-cream is non-dairy, made from vegetable products from crops grown in the UK. This ice cream contains no animal products. a Organic ice cream This ice-cream is made from organic milk produced from cows bred and reared in the UK. Organic farming aims to produce food using natural substances and processes.

Conventional blueberry muffin
This blueberry muffin is made from ingredients produced in the UK.

Reduced-fat blueberry muffin
This reduced-fat blueberry muffin (20% less calories) is made from ingredients produced in the UK.

Reduced-sugar blueberry muffin
This reduced-sugar (20% less calories) blueberry muffin is made from ingredients produced in the UK. beef burger and cultured beef burger in Study arm 1) were indeed different products (see Fig. S1 in supplementary materials for more detail). Food label (e.g., conventional beef burger vs. cultured beef burger) and food photo (e.g., conventional beef burger photo 1 vs. conventional beef burger photo 2) pairing (i.e., label by photo) was balanced across participants. Each food with its accompanying label was rated singly (i.e., not side-by-side with its comparison food). The order of the 12 trials within each study arm was randomised.

Test foods and photos
As outlined in Table 1, there were six conventional test foods in the study: beef burger, chicken nuggets, cheese sandwich, ice cream, blueberry muffin and chocolate chip cookie (the nutrient composition of these foods is shown in supplementary materials Table S1). The purpose of including foods ('filler items') other than the meat/meat-alternative foods, was three-fold. First, we wanted to reduce demand awareness (by reducing the focus on meat products). Second, also consistent with the goal of reducing green-house gas emissions, we included dairy products and their non-dairy alternatives. Third, for comparison, we wanted to collect information on effect sizes for other product differences (conventional vs. reduced fat, reduced sugar, and organic alternatives).
The test foods were prepared by the lead researcher (YV) at University of Bristol, Nutrition and Behaviour Unit kitchen. Each test food was placed on a white plate (255 mm) and colour photographs of the foods were taken with a Canon EOS 70 D camera from 45-degree angle. To process the photos of the foods, we used XnConvert image converter (https://www.xnview.com/en/xnconvert/). The photos used are shown in Supplementary Materials Fig. S1.

Measures
The primary outcome measures in this study were: expected taste pleasantness, fullness, satisfaction, healthiness, willingness to pay and disgust. All outcome measures were based on participants' expectations of pleasantness, fullness, satisfaction etc. However, for the sake of brevity, we refer to these measures as pleasantness, fullness, satisfaction, etc. throughout the paper. Outcome measures, including the anchors 'not at all' and 'extremely' used in this study were based on previous studies. For example, the measure of expected satisfaction was based on a previous study conducted by , which found that food liking and fillingness predicted meal satisfaction. The expected willingness to pay measure was similar to measures used in two previous studies (Brunstrom & Rogers, 2009;Rogers & Hardman, 2015).
Other measures were ratings of hunger, fullness, and thirst, completed before evaluation of the foods. A 100-point visual analogue scale was used for all ratings. The scales were anchored with the phrases 'NOT AT ALL' at the left-hand end and 'EXTREMELY' at the right-hand. Table 3 presents the phrasing of the various measures.
To collect background information, the participants were invited to complete a demographic questionnaire. They were asked to indicate their gender (what is your gender?); date of birth; their self-identified diet type, with options i) vegetarian, ii) vegan iii) omnivore; highest level of education they have completed with options i) A-levels and equivalent, ii) Degree, iii) Higher Degree iv) None (for participants who were currently studying, the wording for the question was highest qualification that they have been awarded). Finally, they were asked to leave their postcode from which we estimated their income level using the English indices of deprivation 2019 online tool (English indices of deprivation 2019: Postcode Lookup (opendatacommunities.org).

Procedure
Participants who expressed an interest in take part in the study were emailed an information form. They were also asked to confirm that they met the eligibility criteria (described in section 2.1. above) stated in the study advert. After this confirmation, they were given an ID number and a link to their (randomly) allocated study arm.
A copy of the information form was also placed in the survey and the participants were asked to confirm that they had read the information, after doing this they were presented with the consent form on the next screen.
After consenting, participants rated their baseline hunger, fullness, and thirst. Next, they were shown a screen displaying the following instruction: "Next you will be asked questions about different foods. The foods will be shown individually in pictures. For each food, you will be asked the 6 different questions (e.g., pleasantness, fullness). So, you will see the picture of each food six times (in succession). When answering the questions about each food, please imagine that you have not eaten for 3 h since breakfast and you are ready to eat the food for lunch. Imagine that it will be the only food that you will have for your lunch. Written information about each food will appear at the bottom of the pictures of the foods. Please be sure to read this information carefully. For each page, when you have made your response, click the arrow in the blue box to proceed to the 'next page'." After the general instruction, the participants were shown test foods and asked to evaluate them on the various 100-point visual analogue scales.
As outlined in above in Table 1 section 2.2. each food was presented singly (not side by side), and participants rated 12 different food and label combinations (i.e., completed 12 food trials in total). The order of the 12 trials was randomised for each participant. The order of questions for each food was always: taste pleasantness, fullness, satisfaction, healthiness, willingness to pay and disgust.
At the end of the study, participants were asked to complete an openended question: "In your opinion, what is the purpose of this study?" to measure demand awareness. Finally, they were presented a 'debriefing form' and asked to enter their email address if they would like to enter the prize draw (public participants). They were then thanked for completing the survey.

Data analysis
The hypotheses and analysis plan were specified prior to data collection (https://osf.io/xz2nt/). All data were transferred from Qualtrics to IBM SPSS Statistics 24 (IBM Corporation, Armonk, NY, USA). A small number of participants (n = 4 public and n = 1 student), with substantial missing data (they did not complete the survey) were excluded from the analysis (leaving a total n of 195).
We calculated mean and standard deviation scores for participants' age, baseline hunger, fullness, and thirst scores. Education level was grouped as (1) 'School Level' (A-levels and equivalent and GCSEs or equivalent) and as (2) 'Higher Education' (degree and higher degree). a To measure willingness to pay, each product pair (conventional meat and alternatives, dairy products, and bakery/confectionery products) were priced according to approximate current (2019) retail prices (e.g., burger and nuggets were priced at £5; cheese sandwich was priced at £4; ice-cream was priced at £2; cookie and muffin were priced at £1).
The data within each study arm, for meat eaters and non-meat eaters, for each food and its alternative (e.g., conventional beef burger and cultured beef burger), for each measure (taste pleasantness, fullness, etc), was analysed using three-way mixed factor ANOVA. The within subjects factor was Label (conventional vs. alternative), and the between subjects factors were Diet (meat eaters and non-meat eaters) and Label by Photo Pairing (e.g, conventional burger/photo 1, cultured burger/ photo 2 vs. conventional burger/photo 2, cultured burger photo 1).
To summarise and compare effects across the six foods and their alternatives we calculated Cohen's d (Lakens, 2013) for the differences between the conventional and alternative labels for each food and each measure (e.g., mean difference in pleasantness scores for conventional and cultured burger divided by the pooled standard deviation of those scores). We graphed these effects sizes separately for meat eaters and non-meat eaters (144 effect sizes in total).
We carried out multiple linear regression analyses to explore if taste pleasantness and fullness independently predicted by satisfaction. We also carried out regression analyses to explore whether satisfaction, together with food disgust and rated food healthiness, predicted willingness to pay. Regression analyses were conducted only for meat eaters (N = 151), as our main purpose was to understand their attitudes towards plant-based meat alternatives and cultured meat in depth. The sample size was also larger for meat-eaters than for non-meat eaters (N = 44).

Results
This study generated a large amount of summary data and statistical results that we were unable to fully accommodate in the main body of this paper. The full results for the meat products (beef burger and chicken nuggets) and their alternatives are summarised below, together with effects sizes for all foods and their alternatives. The further results shown in the supplementary materials.

Participant characteristics
The participants were 150 women, 44 men, and one participant who preferred not to say. They were aged 29 ± 13.4 years (mean ± SD) (range: 18-72). There were 151 meat eaters and 44 non-meat eaters (vegan + vegetarian). 56 per cent (n = 109) of participants had secondary school level qualification and 44 per cent (n = 86) of participants had a higher education level qualification.
According to the open-ended question about the purpose of the study, 90 per cent (n = 176) of participants believed the cover story, indicating that the study was about appreciation of new UK foods. Ten percent gave close estimations regarding the purpose of the study by using words from the advert and the survey such as "perception of plantbased meat alternatives, cultured meat", "disgust" and "to see people's opinions of vegan/vegetarian foods", with only five of those participants (2.6% of the whole sample) indicating that the study was about the effects of labelling on attitudes towards alternatives to conventional meat vs. conventional meat products.

Evaluation of food product pairs by the meat eaters and non-meat eaters
The results for the evaluations (pleasantness, fullness, etc. ratings) of various key product pairs are described below. The relevant summary data (means ± SEs) are shown in Figs. 1-4 and fuller statistical results are shown in Table S2.

Cultured meat alternatives vs. conventional meat products
The meat eaters valued the cultured burger less than the conventional beef burger in terms of lower pleasantness, fullness, satisfaction, and willingness to pay, and higher disgust (Fig. 1). By contrast, the nonmeat eaters valued these two products similarly, except for lower disgust for the cultured burger.
The same pattern of results for disgust was repeated for cultured vs. conventional chicken nuggets (Fig. 2); namely the meat eaters displaying higher disgust for the cultured than the conventional chicken product, and the non-meat eaters displaying lower disgust for the cultured than the conventional product. Notably, both the meat eaters and non-meat eaters rated the cultured nuggets as healthier than the conventional chicken nuggets. Apart from disgust and healthiness, the meat eaters valued the two nugget products similarly (pleasantness, fullness, satisfaction, and willingness to pay).
Overall, except for fullness, the non-meat eaters valued both the burger and nugget products lower than did the meat eaters (Figs. 1 and 2, and Table S2). Fig. 3 shows that the meat eaters valued the two burgers similarly in terms of pleasantness, satisfaction, disgust, and willingness to pay, but they rated the plant-based less filling than the conventional burger. By contrast, the non-meat eaters valued the plant-based burger more highly than the conventional burger in terms of higher pleasantness, satisfaction, and willingness to pay, and lower disgust. Both the meat eaters and the non-meat eaters rated the plant-based burger healthier than the conventional beef burger.

Plant-based alternatives vs. conventional meat products
For the chicken nuggets, the meat eaters valued the plant-based nuggets lower than the conventional nuggets in terms of pleasantness, fullness, satisfaction, and willingness to pay (Fig. 4). For the non-meat eaters, the pattern of results for the nuggets was similar to the pattern of results for the burgers, with greater value placed on the plant-based product, including lower disgust. Again, both the meat eaters and nonmeat eaters rated the plant-based meat alternatives as healthier than their conventional counterparts (Figs. 3 and 4, and Table S2).

Comparison of other product pairs
The results of comparison between conventional vs. vegan dairy products (cheese sandwich and ice cream); and conventional vs. organic dairy products (cheese sandwich and ice cream), overall, showed that both meat eaters and non-meat eaters valued the vegan and organic alternatives more than their conventional counterparts in terms of healthiness (Table S2). The results of the other filler items (blueberry muffin and chocolate chip cookie) indicated that reduced-fat and reduced-sugar alternatives were rated as healthier than the conventional counterparts by both meat eaters and non-meat eaters (Table S2). Fig. 5 shows the effect sizes graphs, indicating meat eaters' and nonmeat eaters' evaluation of different food products compared with their conventional counterparts. For alternatives to animal products, the direction of effects differed between meat eaters and non-meat eaters in terms of pleasantness, satisfaction (specifically for plant-based meat alternatives), disgust and willingness to pay, with the effect sizes tending to be smaller for meat-eaters. For healthiness, however, both groups valued the alternatives to meat products more highly.

The relative effect sizes between product pairs
The effect sizes for the alternatives to animal products (e.g., cultured beef burger vs. conventional beef burger, or plant-based burger vs. conventional beef burger) were on average substantially larger that the effect sizes for other product alternatives (e.g., organic ice cream vs. conventional ice cream, or reduced-fat blueberry muffin vs. conventional blueberry muffin).
We conducted a sensitivity analysis in which we repeated the main data analyses described above after removal from the data set of participants (10% of the total sample) who demonstrated at least partial awareness of the true purpose of the study from the data set. The patterns of results for both meat eaters and non-meat eaters were very similar to the results for the full sample of participants, except that for non-meat eaters some effect size increased for plant-based burger (e.g., for pleasantness, healthiness, and disgust). The sensitivity analysis effect sizes graphs are shown in Fig. S2 in supplementary materials.

Expected meal satisfaction and willingness to pay for products
Meal satisfaction was predicted by pleasantness and expected fullness. Overall (i.e., across all foods), pleasantness was a stronger predictor of satisfaction (max β = 0.76, p < .001; min β = 0.34, p = .002) than was fullness (max β = 0.55, p < .001; min β = 0.17, p = .005). Mean adjusted R 2 was 0.54. The presented values ranging between max and min of β and values ranging smallest to largest p values. β coefficients, pvalues and R 2 values are shown separately for the various test foods in supplementary materials Table S3.
Overall (i.e., across all foods), willingness to pay was predicted by meal satisfaction (a significant contributor for all test foods, mean max β = 0.52, p < .001; min β = 0.33, p = .004), and to a lesser extent by    Table S4.

Discussion
Strategies aiming to reduce animal-sourced foods, in particular conventional meat products, due to its adverse impact on the planet, human health, and animal welfare target meat eaters, yet reducing meat intake is not requested by meat eaters (Hoek, 2010). In addition, perceived nutritional value and sensory attributes of conventional meat have been suggested as important barriers to reduce these products. Therefore, alternatives to conventional meat have been on the spotlight in recent years to overcome these challenges. In this study, meat eaters and non-meat eaters' attitudes were investigated towards plant-based meat alternatives and cultured meat compared to conventional meat.
Consistent with our first hypothesis, meat eaters overall valued conventional meat products more than alternatives to conventional meat products. Contrary to our prediction, they rated plant-based meat alternatives and cultured meat as 'healthier' options than their conventional counterparts. However, differences in ratings were observed depending on the type of alternatives to conventional meat (plant-based and cultured), diet type (meat eaters and non-meat eaters) and product pair comparisons (beef burger and chicken nuggets).
When plant-based burger and conventional burger were evaluated by meat eaters, both products were equally valued on most outcome measures (e.g., expected pleasantness, satisfaction, and willingness to pay etc.). However, there were noticeable differences in this comparison regarding expected fullness and perceived healthiness. While plantbased burger was rated less filling compared to conventional burger, it was rated as much healthier than conventional burger. For the comparison of plant-based nuggets and conventional chicken nuggets, the plant-based alternative was again rated as substantially healthier than conventional product.
Meat eaters' evaluation of cultured meat products versus conventional meat products showed different patterns based on product type (burger or nuggets). Cultured burger was less valued than its conventional counterpart, most noticeably in respect of disgust and taste pleasantness. By contrast, disgust and taste pleasantness differed relatively little between cultured and conventional chicken nuggets. Furthermore, perceived healthiness was higher for the cultured chicken nuggets. These findings for the cultured chicken product are novel, as little is known regarding positive attitudes expressed towards cultured meat. Studies to date have generally concluded that consumers find cultured meat to be 'unnatural' (Wilks, Hornsey, & Bloom, 2021) and 'unhealthy' (Verbeke et al., 2015). The present study, however, suggests that there is an opportunity to motivate consumers to accept cultured meat products by promoting the perception of the healthiness of these products. On the other hand, these results should viewed in the context of the current limited availability and relative high cost of cultured meat products.
As a second and important part of our first hypothesis, we also investigated the role of disgust in acceptance of alternatives to conventional meat. Contrary to our hypothesis, there was not a statistically significant difference in meat eaters' disgust ratings in their evaluation of plant-based products (for both plant-based product types) compared to conventional meat products. However, as predicted, meat eaters rated the cultured meat products, especially the cultured burger, as more disgusting than their conventional counterparts. Disgust expressed towards cultured meat is consistent with previous findings Siegrist & Hartmann, 2020a;Verbeke et al., 2015), which likely comes, in part at least, from the 'unfamiliarity' of cultured meat products (Bryant & Barnett, 2018; that in turn creates a perception of increased risk (Siegrist, Bearth, & Hartmann, 2020b).
Satisfaction and willingness to pay were primary outcome measures and, as hypothesised from previous research Shahrokni, Ferriday, Motou, Brunstrom, & Rogers, 2018), taste pleasantness and fullness predicted satisfaction. Furthermore, satisfaction, together with a smaller contribution from healthiness and/or disgust, predicted willingness to pay. These results can, in turn, explain the important finding that meat eaters' overall valuation (willingness to pay measure) of plant-based alternatives was similar to, or only somewhat lower than their valuation of meat products. Specifically, it seems that meat eaters' lower satisfaction for plant-based meat alternatives is at least partly offset by their perception that plant-based meat alternatives are healthier.
In this context, the results for the filler items provided further insight into meat eaters' attitudes towards animal product alternatives (e.g., cultured, plant-based and vegan dairy products) compared with the other, filler-item product alternatives (e.g., organic dairy products and low-fat or low-sugar bakery/confectionary products). Importantly, the effect sizes for healthiness of plant-based alternatives compared with meat products were mostly larger than the effect sizes for healthiness of organic, reduced sugar and reduced fat products compared with their equivalent conventional products. This demonstrates that the perceived healthiness advantage of plant-based alternatives to meat product is not trivial, and therefore could be a useful focus for the promotion of such products. Nonetheless, as described above, this may not compensate fully for the lower satisfaction expected from these products, which appears to be driven by expectations of both reduced taste pleasantness and reduced fillingness.
By contrast, satisfaction did not differ between the organic alternatives and their conventional counterparts, or, more surprisingly, between reduced fat and reduced sugar products and their conventional counterparts. Consistent with this, neither taste pleasantness nor fillingness were expected to be much affected by reduced sugar or reduced fat content, which supports this approach to combating excessive energy intake (e.g., Rogers & Appleton, 2021).
Non-meat eaters highly valued plant-based meat alternatives in most respects, except for the fillingness of plant-based vs. conventional chicken nuggets. As predicted, and unsurprisingly, non-meat eaters also rated conventional meat products as substantially more disgusting than their plant-based alternatives. Notably, non-meat-eaters expressed less disgust towards the cultured meat products than they did towards the conventional meat products.
Although there was not a specific hypothesis for non-meat eaters' attitudes towards cultured meat vs. conventional meat products, results showed that non-meat eaters valued cultured vs. conventional products similarly, except for lower disgust for the cultured burger. In this study, cultured meat products were labelled as 'slaughter-free' to be factually accurate and to align with its original description as an 'animal-friendly' way of meat production (Post, 2012). We suggest that 'slaughter-free' label of cultured meat may have acted as a prime for animal welfare in non-meat eaters' evaluations, resulting in the lower disgust they expressed towards the cultured meat products compared to conventional meat products. This argument is also supported by a previous study where the 'animal welfare' aspect of cultured meat was proposed to reduce non-meat eaters' disgust towards those products (North, Klas, Ling, & Kothe, 2021).

Strengths and limitations of this study and future direction
To sum up, this study complements and contributes to the literature Fig. 5. Effect sizes for the evaluation of different food products compared with their conventional counterparts (e.g., cultured beef burger vs. conventional beef burger). The data are the alternative product minus the conventional product (with disgust ratings reversed scored). So, a negative effect size represents lower valuation of the alternative product, and a positive effect size represents higher valuation of the alternative product. on attitudes to alternatives to conventional meat products. We used measures validated in previous research on food acceptance, including in studies which involved actual consumption of the foods in question. The present results replicated the relationships between measures demonstrated in that research, for example, we found, as hypothesised, that taste pleasantness and fillingness predicted satisfaction.
We took great care in drafting the descriptions of the various food products. We were aware especially of the importance of the information we provided about the, unfamiliar, cultured meat products. Our choice of words, which included the phrase 'produced without animal slaughter' and supporting information, was similar in length and sentence construction to the descriptions used for the other food products. Whilst this phrase is not affectively neutral, it is realistic and factually correct, in contrast to, for example, referring to cultured meat as 'clean meat' or 'lab-grown meat' (it will not be 'lab grown', when it is scaled up for large scale production). A bland, fully neutral, description does not reflect how food products are described. Accordingly, we also included positive phrases such as 'grown in the UK' (implying, for the study participants, local production), for the other food products. Evidence that our description of the cultured meat products was not unrealistically positive, is that these products were rated as significantly disgusting by meat eaters. Having said this, we do not claim that the description of cultured meat we used did not positively affect meat eaters' responses in this study.
A limitation of this study was grouping meat eaters and non-meat eaters simply as two groups, which, for example included potential flexitarians in the 'meat eaters' group, whilst vegans and vegetarians were grouped as 'non-meat eaters'. This should be addressed in future research, especially considering the literature suggesting that meat eaters and flexitarians have different motivations concerning conventional meat consumption, and therefore that they should be targeted separately in relation to reducing their meat consumption (Becker & Lawrence, 2021; Onwezen et al., 2021).
Overall, future studies should investigate how the description of cultured meat affects its acceptance, whilst also considering how this does or does not vary between consumer segments and as a function of differing motives for reducing consumption of conventional meat products.
A limitation of research on novel or relatively novel products is that, by definition, consumers will be unfamiliar with those products. We did not measure participants' familiarity with the products they evaluated, although without doubt, few or likely none of them will have eaten any cultured meat products. On the other hand, plant-based meat alternatives are commonly visible in UK supermarkets. Therefore, we assume that UK consumers, in general, are familiar with these products. Our description of the various products, with its corresponding picture (in all cases a photograph of a 'conventional' product), provided, together with participants' existing knowledge of the product or product type, the basis for their evaluative judgements. Familiarity, in part is a measure of acceptance (we eat food that we like, and like food that we eat). Nonetheless, the effect of familiarity goes beyond the frequency of consumption, for example the literature shows that when consumers become more familiar with/aware of plant-based meat alternatives and cultured meat, they become more open to accepting these products . In that respect, it would have been informative to include a familiarity measure in the present study, and we recommend doing this in future similar studies.
A final point is that the effect size graphs provided a method for summarising a large amount of data in a way that facilitates the comparison of the different products across the various measures. Nonetheless, large effects on a measure (e.g., healthiness) do not necessarily translate into a large effect on overall acceptance (as measured by, for example, willingness to pay), as healthiness in this example is one among several predictors of acceptance, as demonstrated by the results of the multiple regression analyses. Moreover, relative importance of variables such as healthiness will likely differ across consumer segments, which again highlights the imporance of a finer grained analysis of individual differences. Likewise, in future studies it may well be worth making comparisons between, for example, cultured meat and organic meat. In the present study, our purpose of including, for example, organic ice cream rather than organic meat, was to reduce demand awareness in respect of the key alternatives to the conventional meat products, namely the cultured meats and the plant-based alternatives.

Conclusion
Key conclusions of this study are 1) alternatives to conventional meat products are in part acceptable to both meat eaters and non-meat eaters. 2) Meat eaters' lower satisfaction for plant-based meat alternatives is driven by expectations of both poorer taste pleasantness and reduced fillingness. However, plant-based meat alternatives have an advantage of a higher perceived healthiness. 3) Cultured meat products are rated as equally or more healthy by meat eaters, but as more disgusting than their conventional counterparts. 4) These results have implications for public promotion of a change in diet -higher perceptions of healthiness can be used to promote alternatives to conventional meat whilst at least partly balancing reduced taste pleasantness and fillingness and, for cultured products, a high level of disgust.

CRediT author statement
Yeliz Vural: Conceptualisation, Methodology, Investigation, Data analysis and interpretation, writing of original draft. Danielle Ferriday: Writing -review and editing, Supervision. Peter Rogers: Conceptualisation, Methodology, Writing -review and editing, Supervision.

Funding
Yeliz Vural was funded by a scholarship awarded by the Turkish Ministry of National Education, Republic of Turkey. This funder played no direct role in influencing the nature of the research or the decision to submit the article for publication.