Protein production: planet, profit, plus people?

Postprandial Aminoacidemia Following the Ingestion of Alternative and Sustainable Proteins in Humans: A Narrative Review

There is a pressing need to expand the production and consumption of alternative protein sources from plants, fungi, insects, and algae from both nutritional and sustainability perspectives. It is well known that the postprandial rise in plasma amino acid concentrations and subsequent muscle anabolic response is greater after the ingestion of animal-derived protein sources, such as dairy, meat, and eggs, than plant-based proteins. However, emerging evidence shows that a similar muscle anabolic response is observed-despite a lower and slower postprandial aminoacidemia-after the ingestion of alternative protein sources compared with animal-derived protein sources. Therefore, a comprehensive analysis of plasma amino acid kinetics after the ingestion of alternative protein sources would play a significant role in recognizing and identifying the anabolic properties of these protein sources, allowing for the implementation of the best nutritional intervention strategies, contributing to more sustainable food production, and developing new medical nutritional products with optimal impacts on muscle mass, strength, and function, both in terms of health and disease. Therefore, this narrative review is focused on postprandial amino acid kinetics (the area under the curve, peak, and time to reach the peak concentration of amino acids) based on experimental randomized controlled trials performed in young and older adults following the ingestion of different novel, sustainable, and alternative protein sources.

Microwave-assisted extraction enhances Aquafaba functionality: A high value-added egg white replacer in vegan meringue production

This study aimed to compare microwave-assisted extraction (MAE) with conventional extraction methods regarding the physicochemical, techno-functional, molecular, and thermal properties of chickpea aquafaba. The potential of microwave-extracted aquafaba (MAEA) as an egg white replacer in vegan meringue production was also evaluated. The results indicated that while MAE reduced extraction yield and foam stability, it enhanced protein content, density, dry matter, and foaming ability compared to conventionally extracted aquafaba (CEA). X-ray diffraction revealed a reduction in protein crystal size, and FT-IR analysis confirmed the absence of harmful compounds in MAEA. Thermogravimetric analysis (TGA) identified key thermal degradation points. Substituting egg whites with aquafaba affected batter properties and meringue characteristics, but sensory evaluation showed no significant differences. Meringue with 50 % aquafaba substitution had the highest quality score, suggesting that this replacement offers economic and environmental benefits while meeting consumer preferences.

Pilot scale production of high-content mycoprotein using Rhizopus microsporus var. oligosporus by submerged fermentation and agro-industrial by-products

While mycoprotein has gained traction as a human food source, its potential as a nutrient for animals remains largely unexplored. The mycoprotein-producing Rhizopus microsporus var. oligosporus, a fungus traditionally used for human food in Indonesia, is promising. It could revolutionise animal nutrition once it is Generally Recognized as Safe (GRAS) and is a biosafety level 1 (BSL1) organism. To enhance sustainably, we propose using sugar cane molasses (SM) and corn steep liquor (CSL) as nutrient sources. Also, we investigated the growth of R. microsporus var. oligosporus in five 14 L external-loop airlift bioreactors using CSL as the sole nutrient source. After 96 h of fermentation, at 25 °C and 0.5 vvm, the mycelium produced had an average biomass yield of 38.34 g L-1, with 70.18 % (m v-1) crude protein (mycoprotein). This bioprocess, which is scalable and economically viable, produces high amounts of mycoprotein for animal feed using CSL, a cost-effective agro-industrial by-product, providing a practical solution to the growing demand for animal protein.

Age matters: The effect of regret and loss aversion on cultured meat acceptance

Cultured meat shows great promise as a more sustainable alternative to conventional meat consumption. However, consumer acceptance of cultured meat remains a great challenge as studies indicate a general reluctance to adopt this product. Notably, while existing literature has provided various factors influencing consumer acceptance of cultured meat, there is a limited focus on the use of affective cues. The present research examines the impact of regret appeal on consumers' willingness to try cultured meat. In two experimental studies, the authors investigate (1) the interactive effect between regret and age on willingness to try cultured meat, and (2) the role of loss aversion as a mediating factor between regret and willingness to try cultured meat. The results demonstrate the effectiveness of regret appeal in increasing consumers' willingness to try cultured meat, particularly among older populations. This is because older populations exhibit higher levels of loss aversion. The present study is the first to shed light on the interactive effect of regret and age in influencing sustainable product acceptance. Furthermore, the study establishes the first empirical evidence to demonstrate that loss aversion is a valid self-regulating strategy adopted to cope with the feeling of regret in a consumption context.

Formulation of new sourdough bread prototypes fortified with non-compliant chickpea and pea residues

Purpose

Nowadays, the promotion of a circular economy is fundamental to reduce food losses and waste. In this context, the possibility of using food supply chains non-compliant residues emerges. Much interest has been directed toward legume residues, in general and, in particular, to the possibility of combining different plant-matrices to improve nutritional profile, providing high-quality products.

Methods

Five different formulations of breads, with a combination of seeds and cereals, were fortified with chickpea and pea protein concentrates. Samples were analyzed and compared with their relative control recipe to determine differences in composition, actual protein quality and integrity, and protein digestibility (performed with the INFOGEST method).

Results

Samples showed a clear improvement in the nutritional profile with higher values of proteins, from averagely 12.9 (control breads) to 29.6% (fortified breads) (17.7-24.7 g/100 g of dry matter respectively), and an improvement in amino acidic profile, with a better balancing of essential amino acids (lysine and sulfur amino acid contents), without affecting protein integrity. Regarding in vitro gastro-intestinal digestibility, sample C (19% chickpea proteins) showed the best results, having a comparable protein digestibility to its control bread-48.8 ± 1.1% versus 51.7 ± 2.3%, respectively.

Conclusion

The results showed how the fortification with chickpea and/or pea protein concentrate improved the nutritional profile of bread. These prototypes seem to be a valid strategy to also increase the introduction of high biological value proteins. Furthermore, the not-expected lower digestibility suggested the possible presence of residual anti-nutritional factors in the protein concentrates interfering with protein digestibility. Therefore, it seems of fundamental importance to further investigate these aspects.

Is Sustainable Consumption a Sufficient Motivator for Consumers to Adopt Meat Alternatives? A Consumer Perspective on Plant-Based, Cell-Culture-Derived, and Insect-Based Alternatives

This study investigates consumer preference and acceptance of three meat alternatives-plant-based, lab-grown, and insect-based-as sustainable choices to meet the demands of a growing population and evolving food systems. Insights were gathered from European consumers regarding their perceptions and consumption patterns using a mixed-methods approach. The approach employed a questionnaire followed by focus group discussions conducted in Slovenia and the UK to understand the motivations and barriers behind their responses. The UK and Slovenia were chosen as they provided the highest response rates to the questionnaire and they have differing legislation. The results show that plant-based alternatives are the most familiar and accepted option, while lab-grown meat and insect-based products are less familiar and have lower acceptance rates. Moreover, they show that although sustainability factors are important to consumers, they are not their only concern; health and nutrition are the primary motivators for choosing meat alternatives. These are followed closely by sensory appeal, pricing, and a preference for natural, minimally processed options. Based on insights from the focus groups, strategies to overcome the barriers to the acceptance of meat alternatives should include targeted product categorisation and placement, educational campaigns, effective use of media, and greater transparency in product information.

In vitro protein digestibility of RuBisCO-enriched wheat dough: a comparative study with pea and gluten proteins

Growing demand for sustainable, plant-based protein sources has stimulated interest in new ingredients for food enrichment. This study investigates the nutritional and digestive implications of enriching wheat dough with RuBisCO, in comparison to pea protein-enriched and gluten-enriched doughs. The protein quality and digestibility of these enriched doughs were analysed through dough characterization, in vitro digestion experiments and biochemical analysis of digesta. Our findings indicate that an enrichment at 10% of RuBisCO or pea proteins improves the chemical score and the in vitro PDCAAS (IV-PDCAAS) score of wheat dough as compared to the control dough. Digestibility assays suggest that RuBisCO introduction modifies the protein hydrolysis kinetics: the nitrogen release is lower during gastric digestion but larger during intestinal digestion than other samples. The analysis of the protein composition of the soluble and insoluble parts of digesta, using size-exclusion chromatography, reveals that the protein network in RuBisCO-enriched dough is more resistant to gastric hydrolysis than the ones of other doughs. Indeed, non-covalently bound peptides and disulfide-bound protein aggregates partly composed of RuBisCO subunits remain insoluble at the end of the gastric phase. The digestion of these protein structures is then mostly performed during the intestinal phase. These results are also discussed in relation to the digestive enzymatic cleavage sites, the presence of potential enzyme inhibitors, the protein aggregation state and the secondary structures of the protein network in each dough type.

Development of the lexicon, trained panel validation and sensory profiling of new ready-to-eat plant-based " meatballs" in tomato sauce

Background

Providing educational content for children and parents can promote healthy nutritional habits. During the TITAN project, a pilot digital contest where participants have to developed ready-to-eat meatballs in sauce, using only plant-based ingredients, will be tested. The objective of this study was to develop the lexicon needed to objectively assess the sensory profile of this product.

Methods

Eight judges were recruited and trained. Thirteen 1-hour sessions took place over three months. The steps followed were the selection of commercial reference, generation of descriptors, training of the panel, validation of the trained panel and product characterisation. The judges chose one commercial reference (using simple hedonic evaluation) to serve as a reference. The accepted intensity scale for the generated descriptors was from 0 (low intensity) to 9 (very intense). To test the first versions of the game, food product developers involved in the project, acted as participants, and used a mix of lentils, quinoa, and oats to enhance the commercial version. R-project software was used to analyse the performance of the panel and the sensory profiles.

Results

A glossary with 14 descriptors was generated. The discriminatory capacity of the panel was confirmed by examining the significance of the product effect (p < 0.05). The product-judge interaction was not significant (p > 0.05) for most of the evaluated attributes, indicating a good degree of panel agreement. Overall, the panel was considered reproducible after 9 sessions. Although the appearance, firmness, fragility and chewiness were considered similar to the reference, juiciness and taste (understood as meaty flavour) of the new product were deemed improved.

Conclusions

According to the panel, two of the most appreciated attributes associated with meat analogues, juiciness and taste, were improved compared to the commercial reference. Therefore, the first approach for further development of the contest/game was validated.

A systematic review of the definitions, narratives and paths forwards for a protein transition in high-income countries

The protein transition, aiming to rebalance protein intake between animal and alternative proteins, is gaining momentum in scientific and policy discussions on food system transformation. Here, using a systematic review approach, we identified 33 articles that address challenges in reducing the environmental impacts of protein production and consumption, providing healthy diets for a growing population and preventing adverse effects of industrial livestock production systems. We found unclear definitions of the protein transition, conflicting views on reduction or replacement of dietary protein and a lack of attention to systemic change by reducing protein to its macronutrient function. Three narratives were identified, namely, the consumer narrative focusing on consumption-based solutions targeting dietary changes; the techno-centred narrative developing new, more resource-efficient protein production systems; and the socio-technological narrative that intends to transition the agri-food system from an animal-dominated regime to an alternative protein regime. We conclude that solutions should consider factors such as scale, initiating actors and expected impact to support complementary protein transition approaches.

Investigating proliferation and differentiation capacities of Hanwoo steer myosatellite cells at different passages for developing cell-cultured meat

The aim of study was to investigate proliferation and differentiation capacities of Hanwoo myosatellite cells for the development of Hanwoo cell cultures. From P1 to P19, the number of live cells decreased and the cell size increased. It was confirmed that the PAX7 mRNA was higher in P3 than P6 and P9 (p < 0.05). The maximum differentiation score was measured from P1 to P12. The maximum differentiation score maintained high from P1 to P10. Immunostaining was performed for both P1 and P10 cells to investigate differentiation characteristics. And there were no significant differences in differentiation characteristics between P1 and P10 cells. MYOG mRNA was low, whereas C-FOS mRNA was high (p < 0.05) in the late passage. Myosin and Tom20 protein also showed low values in the late passage (p < 0.05). In conclusion, our results suggest that it is appropriate to use P1 to P10 for the production of cultured meat using Hanwoo muscle cells. If cell culture meat production is performed without differentiation, the passage range may increase further. These results provide basic essential data required for further development of Hanwoo cell cultures, which could provide a valuable source of protein for human populations in the future.

Beyond Meat: Alternative Sources of Proteins to Feed the World

A number of changes and social factors such as the expected population growth, the raising demand for animal proteins, food chain disruption due to the COVID-19 pandemic and conflicts are placing food security and sustainable diet at the very centre of the political agenda [...].

Xylo-oligosaccharides improve the adverse effects of plant-based proteins on weaned piglet health by maintaining the intestinal barrier and inhibiting harmful bacterial growth

Introduction

Piglets are more susceptible to weaning stress syndrome when fed high levels of plant-based proteins that contain abundant food antigens and anti-nutritional factors. Xylo-oligosaccharides (XOS) are a potential prebiotic that may improve the tolerance of weaned piglets to plant-based proteins. The aim of this study was to investigate the effects of XOS supplementation in high and low plant-based protein diets on growth performance, gut morphology, short-chain fatty acid (SCFA) production, and gut microbiota of weaned piglets.

Methods

A total of 128 weanling piglets with an average body weight (BW) of 7.63 ± 0.45 kg were randomly allocated to one of the four dietary treatments in a 2 × 2 factorial arrangement, with two levels of plant-based proteins (d 1-14: 68.3 or 81.33%, d 15-28: 81.27 or 100%) and XOS complex (0 or 0.43%) over a 28-day trial.

Results

The growth performance of piglets did not differ significantly among groups (P > 0.05). However, the diarrhea index of weaned piglets fed a high plant-based protein diet (HP) was significantly higher than that of those fed a low plant-based protein diet (LP) at days 1-14 and throughout the experimental period (P < 0.05). XOS treatment tended to reduce the diarrhea index at days 1-14 (P = 0.062) and during the whole experiment period (P = 0.083). However, it significantly increased the digestibility of organic matter at days 15-28 (P < 0.05). Moreover, dietary XOS supplementation increased ileal mucosa mRNA expression of occludin and ZO-1 (P < 0.05). Furthermore, the concentration of butyric acid (BA) in the cecal contents and in the concentrations of BA and valeric acid (VA) in colon contents were significantly elevated in the XOS groups (P < 0.05). Additionally, XOS optimized the gut flora by lowering the number of pathogenic bacteria such as p_Campylobacterota, thereby stabilizing the gut ecosystem.

Discussion

In conclusion, the HP diet aggravated diarrhea in weaned piglets while the XOS diet alleviated it by improving nutrient digestibility, protecting intestinal morphology, and optimizing the gut flora.

Consumer Preference Segments for Plant-Based Foods: The Role of Product Category

A survey of willingness to consume (WTC) 5 types of plant-based (PB) food was conducted in USA, Australia, Singapore and India (n = 2494). In addition to WTC, emotional, conceptual and situational use characterizations were obtained. Results showed a number of distinct clusters of consumers with different patterns of WTC for PB foods within different food categories. A large group of consumers did not discriminate among PB foods across the various food categories. Six smaller, but distinct clusters of consumers had specific patterns of WTC across the examined food categories. In general, PB Milk and, to a much lesser extent, PB Cheese had highest WTC ratings. PB Fish had the lowest WTC, and two PB meat products had intermediate WTC. Emotional, conceptual and situational use characterizations exerted significant lifts/penalties on WTC. No penalty or lifts were imparted on WTC by the situational use of 'moving my diet in a sustainable direction', whereas uses related to 'when I want something I like' and 'when I want something healthy' generally imparted WTC lifts across clusters and food categories. The importance of this research for the study of PB foods is its demonstration that consumers are not monolithic in their willingness to consume these foods and that WTC is often a function of the food category of the PB food.

Determinants of tyrosinaemia during nitisinone therapy in alkaptonuria

Nitisinone (NIT) produces inevitable but varying degree of tyrosinaemia. However, the understanding of the dynamic adaptive relationships within the tyrosine catabolic pathway has not been investigated fully. The objective of the study was to assess the contribution of protein intake, serum NIT (sNIT) and tyrosine pathway metabolites to nitisinone-induced tyrosinaemia in alkaptonuria (AKU). Samples of serum and 24-h urine collected during SONIA 2 (Suitability Of Nitisinone In Alkaptonuria 2) at months 3 (V2), 12 (V3), 24 (V4), 36 (V5) and 48 (V6) were included in these analyses. Homogentisic acid (HGA), tyrosine (TYR), phenylalanine (PHE), hydroxyphenylpyruvate (HPPA), hydroxyphenyllactate (HPLA) and sNIT were analysed at all time-points in serum and urine. Total body water (TBW) metabolites were derived using 60% body weight. 24-h urine and TBW metabolites were summed to obtain combined values. All statistical analyses were post-hoc. 307 serum and 24-h urine sampling points were analysed. Serum TYR from V2 to V6, ranging from 478 to 1983 µmol/L were stratified (number of sampling points in brackets) into groups < 701 (47), 701–900 (105), 901–1100 (96) and > 1100 (59) µmol/L. The majority of sampling points had values greater than 900 µmol/L. sPHE increased with increasing sTYR (p < 0.001). Tyrosine, HPPA and HPLA in serum and TBW all increased with rising sTYR (p < 0.001), while HPLA/TYR ratio decreased (p < 0.0001). During NIT therapy, adaptive response to minimise TYR formation was demonstrated. Decreased conversion of HPPA to HPLA, relative to TYR, seems to be most influential in determining the degree of tyrosinaemia.

Paying for the Greater Good?-What Information Matters for Beijing Consumers' Willingness to Pay for Plant-Based Meat?

Promoting the transition from animal meat to plant-based food consumption has significant benefits for public health and environmental sustainability. This study, involving 526 consumers from Beijing, China, explores how food attributes and information may affect consumers' food choices concerning plant-based meat products. A discrete choice experiment was conducted using burgers with five attributes (meat patties, flavor, sodium content, energy, and price) as the focal product. Separate messages on nutrition, food safety, and the environmental issues related to plant-based meat consumption were also randomly provided to consumers to help examine the role of information. Our findings suggest that Beijing consumers' awareness of plant-based meat is relatively low at present, and they show a negative preference toward plant-based meat consumption relative to that of conventional meat. However, consumers' willingness to pay for plant-based meat significantly increased after nutrition information was provided, but it was not responsive to the provision of food safety or environmental information. These findings suggest that to promote plant-based meat consumption, information closely related to consumers' personal interests rather the "greater good" should be provided, at least in the context of Beijing, China.

Temporal adaptations in the phenylalanine/tyrosine pathway and related factors during nitisinone-induced tyrosinaemia in alkaptonuria

BACKGROUND

Adaptations within the phenylalanine (PHE)/tyrosine (TYR) pathway during nitisinone (NIT) are not fully understood.

OBJECTIVE

To characterise the temporal changes in metabolic features in NIT-treated patients with alkaptonuria.

PATIENTS AND METHODS

Serum (s) and 24-urine (u) homogentisic acid (sHGA, uHGA24), TYR (sTYR, uTYR24), PHE (sPHE, uPHE24), hydroxyphenylpyruvate (sHPPA, uHPPA24), hydroxyphenyllactate (sHPLA, uHPLA24) and sNIT were measured at baseline (V1) and until month 48 (V6) in 69 NIT-treated patients, recommended to reduce protein intake. The 24-h urine urea (uUREA24), creatinine (uCREAT24) and body weight were also measured. Amounts of tyrosine metabolites in total body water (TBW) were derived by multiplying the serum concentrations by 60% body weight, and sum of TBW and urine metabolites resulted in combined values (c).

RESULTS

uUREA24 and uCREAT24 decreased between V1 and V6 during NIT, whereas body weight and sNIT increased. Linear regression coefficient between uUREA24 and uCREAT24 was extremely strong (R = 0.84). sPHE, TBWPHE and cPHE24 increased gradually from V1 to V6. A decrease in cTYR24/cPHE24, sTYR/sPHE and TBWTYR/TBWPHE was seen from V2 to V6. Serum, 24-urine and combined TYR, HPPA and HPLA either remained stable or decreased from V2 to V6.

DISCUSSION

The gradual increase in PHE suggests adaptation to increasing TYR during NIT therapy. The decrease in protein intake resulted in decreased muscle mass and increased weight gain.

CONCLUSION

Progressive adaptation by decreasing PHE conversion to TYR occurs over time during NIT therapy. A low protein diet results in loss of muscle mass but also weight gain suggesting an increase in fat mass.

The Source of Protein or Its Value? Consumer Perception Regarding the Importance of Meat(-like) Product Attributes

Food product attributes may significantly influence the general perception of the product itself, as well as the willingness for its consumption. Assessment of the product is based on customers’ beliefs and individual preferences. Because meat-like products are presented as meat substitutes providing sufficient protein values, the present study aimed to determine the effect of protein source and labelling pointing at high protein content on the evaluation of the product. The experimental online study was conducted with a group of 552 respondents. Four versions of product packaging were designed and tested. These packages differed in the presence or absence of the Nutrition Claim and the presence of the text indicating the vegetable or meat origin of the product. Data collected in the experiment were analyzed using a 2 × 2 ANOVA. The study revealed that the source of protein (plant vs. animal) appears to shape consumers’ perception of the product as more eco-friendly (F (1.518) = 38.681, p < 0.001, η2 = 0.069), natural (F (1.518) = 15.518, p < 0.001, η2 = 0.029), and healthy (F (1.518) = 25.761, p < 0.001, η2 = 0.047). Moreover, labelling including a “high-protein” Nutrition Claim increases the willingness to consume the product (F (1.518) = 4.531, p = 0.034, η2 = 0.009), and provides the impression of it being more eco-friendly (F (1.518) = 6.658, p = 0.01, η2 = 0.012) and of a higher quality (F (1.518) = 7.227, p = 0.007, η2 = 0.014). The obtained results may have theoretical significance by improving the understanding of factors determining the perception of food products and the use of meat substitutes.

Rationalisation of meat consumption in New Zealand adolescents

OBJECTIVE

This study aimed to describe meat consumption rationalisation and relationships with meat consumption patterns and food choice motivations in New Zealand adolescents.

DESIGN

This was a cross-sectional study of adolescents from high schools across New Zealand. Demographics, dietary habits, and motivations and attitudes towards food were assessed by online questionnaire and anthropometric measurements taken by researchers. The 4Ns questionnaire assessed meat consumption rationalisation with four subscales: 'Nice', 'Normal', 'Necessary' and 'Natural'.

SETTING

Nineteen secondary schools from eight regions in New Zealand, with some purposive sampling of adolescent vegetarians in Otago, New Zealand.

PARTICIPANTS

Questionnaires were completed by 385 non-vegetarian and vegetarian (self-identified) adolescents.

RESULTS

A majority of non-vegetarian adolescents agreed that consuming meat was 'nice' (65 %), but fewer agreed that meat consumption was 'necessary' (51 %). Males agreed more strongly than females with all 4N subscales. High meat consumers were more likely to agree than to disagree that meat consumption was nice, normal, necessary and natural, and vegetarians tended to disagree with all rationalisations. Adolescent non-vegetarians whose food choice was motivated more by convenience, sensory appeal, price and familiarity tended to agree more with all 4N subscales, whereas adolescents motivated by animal welfare and environmental concerns were less likely to agree.

CONCLUSIONS

To promote a reduction in meat consumption in adolescents, approaches will need to overcome beliefs that meat consumption is nice, normal, necessary and natural.

Recovery of Functional Proteins from Pig Brain Using pH-Shift Processes

The goal of this work is to explore if pH-shift processing could be used as a cold refinery technique to manufacture pig brain protein isolate (PI). Pig brain protein had the highest solubility at pH 2 (acid method) and pH 12 (alkaline method). As the protein solution’s zeta-potential was near 0 with the lowest solubility, pH 5.0 was chosen as the precipitation pH. Alkaline process produced a 32% dry matter yield with phospholipid content of 35 mg/100 g. The alkaline-made PI was better at forming soft gels and had good emulsifying and foaming capabilities. Although the acid-made PI included less residual lipid and total haem protein and was whiter in colour, it could not be gelled. Acid-made PI was more prone to lipid oxidation with a poorer ability to function as an emulsifier and foaming agent. Thus, functional proteins from pig brain may be isolated using the alkaline pH-shift technique.

Predicting meat consumption from concurrent, automatic appraisals: Introducing nuance to product appraisals

Research into the relationship between automatic product appraisals and consumer behaviour has largely been limited to measuring generic product evaluations (i.e., positive vs. negative). Especially in the context of meat consumption, this approach seems inadequate, as conflicting evaluative product dimensions may play a role in the preference for a plant-based vs. a meat-based diet (e.g., sustainability vs. taste vs. healthiness). We discuss the limitations of this approach and provide a novel tool that can measure automatic appraisals of several stimulus dimensions simultaneously. Using this tool, we register automatic appraisals (health, taste, price, sustainability, ethicality) of meat and vegetarian stimuli, and compare automatic and explicit appraisals in relation to a range of outcome measures, including self-reported likelihood of purchase and reducing meat consumption, willingness to pay, self-reported frequency of meat consumption, and Body Mass Index. Our findings suggest that the measured automatic appraisals represent unique constructs and vary in the degree to which they inform behaviour. Further, variation in the prediction of the outcome variables suggests that the appraisals captured by the explicit and automatic measures differed. Demonstrating unique contributions of the individual automatic appraisals has crucial implications for future research to understand behaviour and improve existing models.

Identifying Belgian protein consumption typologies by means of clustering and classification to move towards personalized advices for sustainable and nutritious food choices

Protein sources are determinant for the environmental impact and nutritiousness of our food consumption patterns. Dietary advices, in terms of nutritional values and, more recently, the associated environmental impacts, are mostly formulated at nationwide level. However, actual food consumption patterns are variable between individuals within nations, leading to a need for more personalized dietary advices to ensure the feasibility of potential dietary changes. This research addresses the variability within Belgian food consumption patterns by identifying different "protein consumption typologies": consumer groups with different consumption frequencies of different protein sources. Hereto, both statistical clustering and classification were applied to food consumption data, the latter using predefined criteria related to meat consumption. The obtained typologies were further analyzed based on personal characteristics and compliance to nutritional guidelines. Five clusters and five classes were identified, with each survey participant belonging to one cluster and to one class. The clusters differed mainly in milk- and grain product intake, while the classes differed in the intake of meat products from the onset. Both clustering and classification showed that only a small part of the Belgian population frequently adopts plant-based protein sources, that meat products are predominant and that compliances to dietary guidelines are generally low. The typologies are the starting point for more personalized dietary advices to lower environmental impacts while ensuring adequate nutritional value, moving away from nationwide advices.

Drivers of Protein Consumption: A Cross-Country Analysis

Consumption and production of proteins derived from animals have more significant environmental and health impacts than proteins derived from plants. This raises concerns mainly in consideration of the predictable increased consumption of animal proteins at the expense of vegetal ones due to growing income, especially in developing countries. Animal protein consumption, and particularly meat consumption, seems to start to decrease at a high level of income, which may suggest that economic growth solves or attenuates the environmental and health problems of animal food consumption. To test this possibility, the relationship between per capita income and animal and vegetal protein consumption is explored. Using a cross-country regression for 142 countries in 2017, animal-based protein, meat protein, and vegetal-based protein consumption are specified as dependent variables. In addition to per capita income, other potential drivers of protein choices, including ecological, demographic and social factors are controlled for. Apart from income, which still seems to be the most important driver of any type of protein consumption, the results suggest that protein consumption from animal sources and meat sources have different determinants. Though there is actually some evidence of an inverted U-shaped relationship between per capita income and animal protein consumption, the peak is at such high levels as to make economic growth irrelevant to curb animal protein consumption.

Sprint Interval Exercise Performance in Vegans

OBJECTIVE

The impact of a vegan diet on sprint interval exercise performance is unknown. Thus, the purpose of the present study was to compare performance during a sprint interval exercise between omnivores and vegans.

METHODS

Nine healthy omnivores (4 men and 5 women) and nine healthy vegans (4 men and 5 women), with similar levels of daily physical activity, performed four bouts (5-min rest between bouts) of a 30-s all-out sprint exercise on a cycle ergometer. Peak power, mean power, fatigue index, and time to reach maximal power output in each bout were recorded.

RESULTS

There was a higher peak power in bouts 1 and 2 compared with bouts 3 and 4 (p < 0.02), and a higher mean power in bout 1 compared with bouts 2, 3 and 4 (p < 0.02). However, for all bouts, there were no significant difference between omnivores and vegans in peak power (7.60 ± 1.55 vs. 8.16 ± 1.27, 7.52 ± 1.6 vs 7.61 ± 0.73, 7.00 ± 1.44 vs. 7.00 ± 1.05 and 6.95 ± 1.42 vs. 6.49 ± 0.90 W.kg^-1, all p > 0.05) and in mean power (5.35 ± 0.93 vs. 5.69 ± 0.84, 5.10 ± 0.88 vs. 5.21 ± 0.49, 4.79 ± 0.81 vs. 4.79 ± 0.45 and 4.81 ± 0.81 vs. 4.69 ± 0.47 W.kg^-1, all p > 0.05). Fatigue index and time to reach maximal power output were not affected by diet or bouts (all p > 0.05).

CONCLUSIONS

These findings indicate that a vegan diet does not compromise sprint interval exercise performance.

Does grazing management provide opportunities to mitigate methane emissions by ruminants in pastoral ecosystems?

Agriculture, and livestock production in particular, is criticized for being a contributor to global environmental change, including emissions of greenhouse gases (GHG). Methane (CH₄) from grazing ruminants accounts for most of livestock's carbon footprint because a large share of them are reared under suboptimal grazing conditions, usually resulting in both low herbage intake and animal performance. Consequently, the CH₄ quota attributed to animal maintenance is spread across few or no animal outputs, increasing the CH₄ intensity [g CH₄/kg live weight (LW) gain or g CH₄/kg milk yield]. In this review, the generalized idea relating tropical pastures with low quality and intrinsically higher CH₄ intensity is challenged by showing evidence that emissions from animals grazing tropical pastures can equal those of temperate grasses. We demonstrate the medium-to-high mitigation potential of some grazing management strategies to mitigate CH₄ emissions from grazing ruminants and stress the predominant role that sward canopy structure (e.g., height) has over animal behavioral responses (e.g., intake rate), daily forage intake and resulting CH₄ emissions. From this ecological perspective, we identify a grazing management concept aiming to offer the best sward structure that allows animals to optimize their daily herbage intake, creating opportunities to reduce CH₄ intensity. We show the trade-off between animal performance and CH₄ intensity, stressing that mitigation is substantial when grazing management is conducted under light-to-moderate intensities and optimize herbage intake and animal performance. We conclude that optimizing LW gain of grazing sheep and cattle to a threshold of 0.14 and 0.7 kg/day, respectively, would dramatically reduce CH₄ intensity to approximately 0.2 kg CH₄/kg LW gain, as observed in some intensive feeding systems. This could represent a mitigation potential of around 55% for livestock commodities in pasture-based systems. Our results offer new insights to the debate concerning mitigation of environmental impacts of pastoral ecosystems.

A systematic review on consumer acceptance of alternative proteins: Pulses, algae, insects, plant-based meat alternatives, and cultured meat

Consumers' dietary patterns have a significant impact on planetary and personal health. To address health and environmental challenges one of the many possible solutions is to substitute meat consumption with alternative protein sources. This systematic review identifies 91 articles with a focus on the drivers of consumer acceptance of five alternative proteins: pulses, algae, insects, plant-based alternative proteins, and cultured meat. This review demonstrates that acceptance of the alternative proteins included here is relatively low (compared to that of meat); acceptance of insects is lowest, followed by acceptance of cultured meat. Pulses and plant-based alternative proteins have the highest acceptance level. In general, the following drivers of acceptance consistently show to be relevant for the acceptance of various alternative proteins: motives of taste and health, familiarity, attitudes, food neophobia, disgust, and social norms. However, there are also differences in relevance between individuals and between alternative proteins. For example, for insects and other novel alternative proteins the drivers of familiarity and affective processes of food neophobia and disgust seem more relevant. As part of gaining full insight in relevant drivers of acceptance, the review also shows an overview of the intervention studies that were included in the 91 articles of the review, providing implications on how consumer acceptance can be increased. The focal areas of the intervention studies included here do not fully correspond with the current knowledge of drivers. To date, intervention studies have mainly focussed on conscious deliberations, whereas familiarity and affective factors have also been shown to be key drivers. The comprehensive overview of the most relevant factors for consumer acceptance of various categories of alternative proteins thus shows large consistencies across bodies of research. Variations can be found in the nuances showing different priorities of drivers for different proteins and different segments, showing the relevance of being context and person specific for future research.

The next protein transition

Background

Meeting the UN Sustainable Development Goals requires a relatively rapid transition towards a circular economy. Therefore, a multidisciplinary perspective is required to sketch why a transition from diets based primarily on animal proteins towards diets based primarily on plant proteins products is extremely urgent for both food security and sustainability.

Scope and approach

This review starts out by identifying ecological, economic and social aspects of sustainable food consumption. Subsequently, it is argued how protein supply is underlying and linking the top-3 of anthropogenic impacts based on the planetary boundaries concept, i.e. 1) biodiversity loss, 2) nitrogen cycle acceleration, and 3) carbon cycle acceleration (resulting in climate change). These environmental impacts associated with current Western food consumption need to be reduced urgently. In order to address the inefficiencies inherent to current dietary patterns, therefore, a ranked list of more sustainable options is proposed, based on their order of magnitude. Addressing consumers, industry, and governmental stakeholders plus cultural aspects, challenges and options are sketched.

Key findings and conclusions

Clearly, a dietary transition from primarily animal towards plant protein products is required. Fortunately, new dietary guidelines are increasingly taking sustainability into account and the contours of a diet transition are slowly emerging.

Analysis of Association between the Consumer Food Quality Perception and Acceptance of Enhanced Meat Products and Novel Packaging in a Population-Based Sample of Polish Consumers

The consumer acceptance of novel enhanced-quality products and their willingness to buy such products may be a crucial topic in the field of marketing. The aim of this study was to analyze the association between consumers’ perceptions of food quality and their acceptance of enhanced meat products and novel packaging. The study was conducted using the Computer-Assisted Personal Interview (CAPI) method in a random group of 1009 respondents, who were recruited as a representative sample based on data from the Polish National Identification Number database. The participants were asked about the most important quality determinants of food products of animal origin and about quality improvement methods and their acceptance of those methods. The quality determinants of animal-based food products were indicated as follows: origin, production technology, manufacturer, components and nutritional value, visual and sensory characteristics, expiry date, and cost. The quality improvement methods were clustered into groups that were associated with product enhancement and application of novel packaging, and the acceptance of those methods was also verified. Indicating specific quality determinants of animal-derived food products affects the consumer acceptance of product enhancement (p = 0.0264) and novel packaging as quality improvement methods (p = 0.0314). The understanding that enhancement is applied for the purpose of quality improvement did not influence the acceptance of products (p = 0.1582), whereas the knowledge that novel packaging is applied influenced the acceptance (p = 0.0044). The obtained results suggested that in the case of application of novel packaging, a higher level of knowledge may be a reason for consumer’s rejection of the resulting products, but the appearance and taste of products may contribute to the higher acceptance of novel packaging. Educating consumers may improve their acceptance of product enhancement, as concerns about the addition of food preservatives may lead them to reject enhanced products.

Comprehensive overview of the quality of plant- And animal-sourced proteins based on the digestible indispensable amino acid score

Indispensable amino acid (IAA) composition and standardized ileal digestibility (SID) of five animal- and 12 plant-based proteins were used to calculate their respective Digestible Indispensable Amino Score (DIAAS) according to the three age categories defined by the Food and Agriculture Organization (FAO). Mean IAA content and mean SID obtained from each protein dataset were subsequently used to simulate optimal nutritional quality of protein mixtures. Datasets revealed considerable variation in DIAAS within the same protein source and among different protein sources. Among the selected protein sources, and based on the 0.5- to 3-year-old reference pattern, pork meat, casein, egg, and potato proteins are classified as excellent quality proteins with an average DIAAS above 100. Whey and soy proteins are classified as high-quality protein with an average DIAAS ≥75. Gelatin, rapeseed, lupin, canola, corn, hemp, fava bean, oat, pea, and rice proteins are classified in the no quality claim category (DIAAS <75). Potato, soy, and pea proteins can complement a broad range of plant proteins, leading to higher DIAAS when supplied in the form of protein mixtures and at specific ratios. Such complementarity highlights the potential to achieve an optimal nutritional efficiency with plant proteins alone.

Analysis of Scientific and Press Articles Related to Cultured Meat for a Better Understanding of Its Perception

Cultured meat is presented by its advocates as a good alternative for consumers who want to be more ethically minded but who do not wish to change their diet. This novel food has become an emerging topic in both the scientific field and the press media. From a bibliometric analysis of scientific publications and on a sociometric analysis of the mainstream press, the aim of this study was to identify potential differences between the scientific view and the public perception. This research analyzed the publications indexed by SCI-EXPANDED in the Web of Science Core Collection database owned by Clarivate Analytics, for scientific literature analysis, and indexed by the Factiva database, for the press media. A total of 327 scientific publications were analyzed according to year of publication and country and institution of origin, also including coauthorships, co-citations, and scientific fields' and journals' networks. A knowledge mapping using VOSviewer was used to study the literature in the field. Based on Factiva, 12,900 press articles dealing with artificial meat, mainly in English, have been found through public databases. The main conclusion is that cultured meat is mainly developing in the USA and the UK, with other countries, such as China, observing the trend for potential future applications. Scientific articles seemed initially to focus mainly on technical aspects of artificial meat and more recently on health value, consumer's acceptance, and sustainability. However, the potential environment-friendly effects of this novel food are more and more studied or described in scientific or press articles.

A catalog of microbial genes from the bovine rumen unveils a specialized and diverse biomass-degrading environment

Background

The rumen microbiota provides essential services to its host and, through its role in ruminant production, contributes to human nutrition and food security. A thorough knowledge of the genetic potential of rumen microbes will provide opportunities for improving the sustainability of ruminant production systems. The availability of gene reference catalogs from gut microbiomes has advanced the understanding of the role of the microbiota in health and disease in humans and other mammals. In this work, we established a catalog of reference prokaryote genes from the bovine rumen.

Results

Using deep metagenome sequencing we identified 13,825,880 non-redundant prokaryote genes from the bovine rumen. Compared to human, pig, and mouse gut metagenome catalogs, the rumen is larger and richer in functions and microbial species associated with the degradation of plant cell wall material and production of methane. Genes encoding enzymes catalyzing the breakdown of plant polysaccharides showed a particularly high richness that is otherwise impossible to infer from available genomes or shallow metagenomics sequencing. The catalog expands the dataset of carbohydrate-degrading enzymes described in the rumen. Using an independent dataset from a group of 77 cattle fed 4 common dietary regimes, we found that only <0.1% of genes were shared by all animals, which contrast with a large overlap for functions, i.e., 63% for KEGG functions. Different diets induced differences in the relative abundance rather than the presence or absence of genes, which explains the great adaptability of cattle to rapidly adjust to dietary changes.

Conclusions

These data bring new insights into functions, carbohydrate-degrading enzymes, and microbes of the rumen to complement the available information on microbial genomes. The catalog is a significant biological resource enabling deeper understanding of phenotypes and biological processes and will be expanded as new data are made available.

Consumer acceptability in the USA, Mexico, and Spain of chocolate chip cookies made with partial insect powder replacement

In the last decade, consumer perception of protein as an important nutrient has increased exponentially and focused on alternative sources such as plant- or insect-based protein and microalgae. However, many consumers indicate that they do not consider insect ingredients, a potential source of high quality protein, to be a good choice in food products. But is it because of the sensory aspects? This consumer study was conducted in the United States of America, Mexico, and Spain to compare acceptability of a familiar product, chocolate chip cookies, in three "blind" variations: a control 100% wheat flour chocolate chip cookie, and two versions substituting 15% and 30% cricket flour for an equivalent amount of wheat flour. Two hundred consumers from each country were recruited and scored overall acceptability and acceptability of different sensory attributes for the three cookies. Acceptance was measured using a nine-point hedonic scale and a similar format was used for each attribute. US consumers did not find significant differences in liking between the control and 15% sample. The 30% cricket powder cookie showed a decrease in consumer acceptance. Mexican and Spanish consumers liked the 15% sample significantly more than the control and 30% sample. Spanish consumers also like the control more than the 30% sample. The substitution of 15% cricket powder does not negatively impact liking in this product and, in fact, may improve both liking and protein content. Further research is necessary to determine whether this finding can help to mitigate the impact of insect-containing ingredients. PRACTICAL APPLICATION: High protein and sustainability are two key aspects being used to promote products in many markets. The protein content and sustainability of insect-based ingredients could make more competitive baked products if certain negative aspects, such as sensory and emotional and psychological barriers, can be overcome. This study focused on three specific countries but products using insect powder as an ingredient have the potential to be used in other regions or countries as acceptable products. With the correct marketing, such products could become a competitive choice in the product category. The food industry should consider and explore different insect powders/flours as an alternative ingredient.

Mindfulness is not associated with dissonant attitudes but enhances the ability to cope with them

Background

Explicit and implicit attitudes have been studied extensively, but there is less attention to reducing dissonance between them. This is relevant because this dissonance (IED) results in distress and has inconsistent effects on behavior, e.g. less physical activity but more smoking. Mindfulness decreases dissonance between self-related explicit and implicit constructs. This study investigates if, and which, specific mindfulness subskills are associated with decreased dissonance between explicit and implicit attitudes, and whether mindfulness subskills moderate the relationship between IED and intention/behavior.

Method

At baseline and one and three months thereafter, participants’ (N = 1476) explicit attitudes, implicit attitudes, red meat consumption (RMC), intention to reduce RMC as well as levels of trait mindfulness were assessed.

Results

Mindfulness subskills were not associated with decreased IED. IED was associated with lower RMC and a higher intention to reduce RMC. The mindfulness subskill acceptance buffered the effect of IED on intention, seemingly offering a skill to deal with dissonant attitudes, which was unidentified until now.

Conclusion

The mindfulness subskill accepting without judgment functions as a way to deal with dissonance. Future research should use this novel finding and investigate whether mindfulness can be used as a buffer in contexts where dissonance results in maladaptive behaviors.

Promoting 'pro', 'low', and 'no' meat consumption in Switzerland: The role of emotions in practices

Meat consumption has become a contentious issue among the Swiss population. The emotional character of the debates surrounding the necessity for a change of habits, namely a reduction in consumption and a shift in the kind of meat we eat, reveals its particular place in our societies: as a symbolic food with roots in our affective economies, as involved in the creation of a shared culture and national identity, and as a political object used to defend different views. To date, research in sustainable consumption has given much attention to environmental- and animal-friendly groups and their practices. However, certain interest groups have been voicing the right to meat, or promoting alternative forms of meat consumption. In this paper, we seek to understand the affective dimension of 'no', 'low' and 'pro' meat consumption initiatives in the Swiss context. Based on a qualitative study and an understanding of emotions as part of social practices, we draw out what affects and related moralities are being mobilized by prescribers and how they are picked up in practice. By doing so, we contribute to further understanding the emotions and moral registers linked to different approaches to meat (non)consumption, their role in promoting certain practices over others, as well as the dynamics that make reducing meat consumption so controversial. We conclude by discussing the need to take emotions and related moralities seriously as a crucial step towards understanding opportunities for 'healthy and sustainable' food practices.

Implicit attitudes and explicit cognitions jointly predict a reduced red meat intake: a three-wave longitudinal study

Background: Despite nutritional benefits, a high consumption of red meat is not without risks as it is linked to the development of certain types of cancer as well as to other non-communicable diseases, such as type II diabetes or cardiovascular diseases. Moreover, the production of meat has negative effects on the environment. Therefore, a transition to a less meat-based diet could be beneficial. It is unclear how explicit cognitions towards red meat consumption and implicit attitudes jointly influence intention and consumption. We tested the additive pattern (both types of cognitions explain unique variance) and interactive pattern (both types interact in the prediction).

Method: At baseline (T0; N = 1790) and one (T1; n = 980) and three months thereafter (T2; n = 556), explicit cognitions, red meat consumption, and implicit attitudes were assessed among a Dutch sample.

Results: Only explicit cognitions were associated with red meat consumption. Implicit attitudes moderated the effect of self-efficacy on T0-RMC; negative implicit attitudes strengthened this effect. T0-intention was associated with explicit cognitions and implicit attitudes. Additionally, negative implicit attitudes strengthened the effect of social norms on T0 and T2-intention. Regarding red meat consumption, support for the interactive pattern was found. For intention there was support for the interactive and additive pattern.

Conclusion: Interventions aiming to reduce red meat consumption in the general public might profit from changing implicit attitudes in addition to explicit cognitions.

The Myth of Cultured Meat: A Review

To satisfy the increasing demand for food by the growing human population, cultured meat (also called in vitro, artificial or lab-grown meat) is presented by its advocates as a good alternative for consumers who want to be more responsible but do not wish to change their diet. This review aims to update the current knowledge on this subject by focusing on recent publications and issues not well described previously. The main conclusion is that no major advances were observed despite many new publications. Indeed, in terms of technical issues, research is still required to optimize cell culture methodology. It is also almost impossible to reproduce the diversity of meats derived from various species, breeds and cuts. Although these are not yet known, we speculated on the potential health benefits and drawbacks of cultured meat. Unlike conventional meat, cultured muscle cells may be safer, without any adjacent digestive organs. On the other hand, with this high level of cell multiplication, some dysregulation is likely as happens in cancer cells. Likewise, the control of its nutritional composition is still unclear, especially for micronutrients and iron. Regarding environmental issues, the potential advantages of cultured meat for greenhouse gas emissions are a matter of controversy, although less land will be used compared to livestock, ruminants in particular. However, more criteria need to be taken into account for a comparison with current meat production. Cultured meat will have to compete with other meat substitutes, especially plant-based alternatives. Consumer acceptance will be strongly influenced by many factors and consumers seem to dislike unnatural food. Ethically, cultured meat aims to use considerably fewer animals than conventional livestock farming. However, some animals will still have to be reared to harvest cells for the production of in vitro meat. Finally, we discussed in this review the nebulous status of cultured meat from a religious point of view. Indeed, religious authorities are still debating the question of whether in vitro meat is Kosher or Halal (e.g., compliant with Jewish or Islamic dietary laws).

Sustainable Diets in the UK—Developing a Systematic Framework to Assess the Environmental Impact, Cost and Nutritional Quality of Household Food Purchases

Sustainable diets should not only respect the environment but also be healthy and affordable. However, there has been little work to assess whether real diets can encompass all three aspects. The aim of this study was to develop a framework to quantify actual diet records for health, affordability and environmental sustainability and apply this to UK food purchase survey data. We applied a Life Cycle Assessment (LCA) approach to detailed food composition data where purchased food items were disaggregated into their components with traceable environmental impact data. This novel approach is an improvement to earlier studies in which sustainability assessments were based on a limited number of “food groups”, with a potentially high variation of actual food items within each group. Living Costs and Food Survey data for 2012, 2013 and 2014 were mapped into published figures for greenhouse gas emissions (GHGE, taking into account processing, transport and cooking) and land use, a diet quality index (DQI) based on dietary guidelines and food cost, all standardised per household member. Households were classified as having a ‘more sustainable’ diet based on GHGE, cost and land use being less than the median and DQI being higher than the median. Only 16.6% of households could be described as more sustainable; this rose to 22% for those in the lowest income quintile. Increasing the DQI criteria to >80% resulted in only 100 households being selected, representing 0.8% of the sample. The framework enabled identification of more sustainable households, providing evidence of how we can move toward better diets in terms of the environment, health, and costs.