Flavor challenges in extruded plant-based meat alternatives: A review.

Demand for plant-based meat alternatives has increased in recent years due to concerns about health, ethics, the environment, and animal welfare. Nevertheless, the market share of plant-based meat alternatives must increase significantly if they are to support sustainable food production and consumption. Flavor is an important limiting factor of the acceptability and marketability of plant-based meat alternatives. Undesirable chemosensory perceptions, such as a beany flavor, bitter taste, and astringency, are often associated with plant proteins and products that use them. This study reviewed 276 articles to answer the following five research questions: (1) What are the volatile and nonvolatile compounds responsible for off-flavors? (2) What are the mechanisms by which these flavor compounds are generated? (3) What is the influence of thermal extrusion cooking (the primary structuring technique to transform plant proteins into fibrous products that resemble meat in texture) on the flavor characteristics of plant proteins? (4) What techniques are used in measuring the flavor properties of plant-based proteins and products? (5) What strategies can be used to reduce off-flavors and improve the sensory appeal of plant-based meat alternatives? This article comprehensively discusses, for the first time, the flavor issues of plant-based meat alternatives and the technologies available to improve flavor and, ultimately, acceptability.

APOE Genotype Disclosure and Lifestyle Advice in a Randomized Intervention Study with Finnish Participants.

BACKGROUND: The APOE ε4 allele is associated with higher risks of cardiovascular diseases and Alzheimer disease than ε3 and ε2. OBJECTIVES: We studied the effectiveness of dietary and lifestyle guidance and personal genetic risk information [ε4 carrier (ε4+); ε4 noncarrier (ε4-)] as motivators for a healthier lifestyle. METHODS: A total of 188 healthy Finnish volunteers (82.4% women; mean ± SD age: 51.0 ± 5.6 y; BMI: 26.0 ± 3.6 kg/m2; total cholesterol: 5.2 ± 0.9 mmol/L) participated in our randomized intervention study. The participants were genotyped for APOE and divided into intervention (INT; INTε4+, n = 33; INTε4-, n = 57) and control groups (CTRL; CTRLε4+, n = 36; CTRLε4-, n = 62). Blood samples, measured observations, and questionnaire data were obtained at baseline and at 1 and 1.5 y. INT participants received their ε4 carrier status at baseline. Monthly Internet-based guidance based on the Finnish Dietary guidelines was provided for all. RESULTS: The proportion of SFAs in plasma over time fluctuated less in INTε4+ than in the other groups (P-interaction < 0.05; primary outcome). The lifestyle guidance increased vegetable consumption from 3.5 to 3.6 portions/d, improved the dietary fat quality score by 5.3%, increased the plasma n-3 (ω-3) FA proportion by 7.3%, and decreased the consumption of high-fat/high-sugar foods from 7.3 to 6.5 portions/wk and total- and LDL-cholesterol concentrations by 4.3% and 6.1%, respectively, in the entire participant population (P < 0.05; secondary outcome). Compared with the ε4- participants, ε4+ participants had 2.4% higher plasma n-6 (ω-6) FA, lower C-peptide (3.9 compared with 4.2 nmol/L × h) and sensitive C-reactive protein values, and decreased plasma malondialdehyde concentrations over time (P < 0.05; secondary outcome). CONCLUSIONS: Lifestyle guidance given to healthy Finnish participants yielded small but beneficial changes. The INTε4+ group did not seem markedly more responsive to the guidance than the other groups.This trial was registered at clinicaltrials.gov as NCT03794141.

Recent Smell Loss Is the Best Predictor of COVID-19 Among Individuals With Recent Respiratory Symptoms.

In a preregistered, cross-sectional study, we investigated whether olfactory loss is a reliable predictor of COVID-19 using a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n = 4148) or negative (C19-; n = 546) COVID-19 laboratory test outcome. Logistic regression models identified univariate and multivariate predictors of COVID-19 status and post-COVID-19 olfactory recovery. Both C19+ and C19- groups exhibited smell loss, but it was significantly larger in C19+ participants (mean ± SD, C19+: -82.5 ± 27.2 points; C19-: -59.8 ± 37.7). Smell loss during illness was the best predictor of COVID-19 in both univariate and multivariate models (ROC AUC = 0.72). Additional variables provide negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms (e.g., fever). Olfactory recovery within 40 days of respiratory symptom onset was reported for ~50% of participants and was best predicted by time since respiratory symptom onset. We find that quantified smell loss is the best predictor of COVID-19 amongst those with symptoms of respiratory illness. To aid clinicians and contact tracers in identifying individuals with a high likelihood of having COVID-19, we propose a novel 0-10 scale to screen for recent olfactory loss, the ODoR-19. We find that numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4 < OR < 10). Once independently validated, this tool could be deployed when viral lab tests are impractical or unavailable.

Factors related to sensory properties and consumer acceptance of vegetables.

Many consumers perceive the bitter taste or other sensory characteristic of vegetables as unpleasant, posing a challenge to dietary recommendations aiming to increase vegetable consumption. Food experience is multisensory, with complex interactions between the senses and individual differences in sensory perception. This review focuses on the factors affecting sensory properties of vegetables and sensory perception of vegetables among adults. Topical examples of sensory quality and evaluation of vegetable samples are presented. Cultivar and growing conditions are related to the internal sensory quality of vegetables. The effects of different processing methods, such as freezing and cooking, on the sensory properties of vegetables are also reviewed. Flavor modification of vegetables with seasonings may be used to improve palatability and incorporating vegetables to meals may increase the intake of vegetables. Recently, external factors (e.g. visual and odor stimuli) have been tested in multisensory research in the context of vegetable perception and choice. These options to achieve better sensory quality, more palatable meals and pleasant eating context may be used to promote vegetable intake among adults.

More Than Smell-COVID-19 Is Associated With Severe Impairment of Smell, Taste, and Chemesthesis.

Recent anecdotal and scientific reports have provided evidence of a link between COVID-19 and chemosensory impairments, such as anosmia. However, these reports have downplayed or failed to distinguish potential effects on taste, ignored chemesthesis, and generally lacked quantitative measurements. Here, we report the development, implementation, and initial results of a multilingual, international questionnaire to assess self-reported quantity and quality of perception in 3 distinct chemosensory modalities (smell, taste, and chemesthesis) before and during COVID-19. In the first 11 days after questionnaire launch, 4039 participants (2913 women, 1118 men, and 8 others, aged 19-79) reported a COVID-19 diagnosis either via laboratory tests or clinical assessment. Importantly, smell, taste, and chemesthetic function were each significantly reduced compared to their status before the disease. Difference scores (maximum possible change ±100) revealed a mean reduction of smell (-79.7 ± 28.7, mean ± standard deviation), taste (-69.0 ± 32.6), and chemesthetic (-37.3 ± 36.2) function during COVID-19. Qualitative changes in olfactory ability (parosmia and phantosmia) were relatively rare and correlated with smell loss. Importantly, perceived nasal obstruction did not account for smell loss. Furthermore, chemosensory impairments were similar between participants in the laboratory test and clinical assessment groups. These results show that COVID-19-associated chemosensory impairment is not limited to smell but also affects taste and chemesthesis. The multimodal impact of COVID-19 and the lack of perceived nasal obstruction suggest that severe acute respiratory syndrome coronavirus strain 2 (SARS-CoV-2) infection may disrupt sensory-neural mechanisms.

Development of an International Odor Identification Test for Children: The Universal Sniff Test.

OBJECTIVE: To assess olfactory function in children and to create and validate an odor identification test to diagnose olfactory dysfunction in children, which we called the Universal Sniff (U-Sniff) test. STUDY DESIGN: This is a multicenter study involving 19 countries. The U-Sniff test was developed in 3 phases including 1760 children age 5-7 years. Phase 1: identification of potentially recognizable odors; phase 2: selection of odorants for the odor identification test; and phase 3: evaluation of the test and acquisition of normative data. Test-retest reliability was evaluated in a subgroup of children (n = 27), and the test was validated using children with congenital anosmia (n = 14). RESULTS: Twelve odors were familiar to children and, therefore, included in the U-Sniff test. Children scored a mean ± SD of 9.88 ± 1.80 points out of 12. Normative data was obtained and reported for each country. The U-Sniff test demonstrated a high test-retest reliability (r27 = 0.83, P < .001) and enabled discrimination between normosmia and children with congenital anosmia with a sensitivity of 100% and specificity of 86%. CONCLUSIONS: The U-Sniff is a valid and reliable method of testing olfaction in children and can be used internationally.

The effect of gender, age and product type on the origin induced food product experience among young consumers in Finland.

Locally produced and sourced food products are gaining popularity among consumers. The effect of the expectations induced by the origin of the food was studied with 1491 consumers in two separate studies among different age groups. In order to test the consumer response to the product origin neutral, domestic, and local conditions were used. Consumers evaluated the product's pleasantness, their probability to choose it, the overall quality, and their willingness to pay. To gather information on whether the phenomenon was consistent, independent from the product category, three different types of products were tested (meat, bread, and vegetables). Our results show that a closer origin does not necessarily produce a positive response, but that there are several moderating factors such as gender, age, and product type. Female university students responded equally to domestic and local origins in the case of bread, but for meat products, only those of local origin induced a positive reaction. In this study population, the male respondents only reacted to a local origin in the case of bread, while domestic meat products provided similar results to local origins. Among young men consumers in the 7th-9th grades responded to the local origin of vegetables positively, while others among the youngest consumers, the origin did not induce a significant effect. The results indicate that even when the product is not appealing itself, locality can still increase the perceived quality.

Self-Ratings of Olfactory Performance and Odor Annoyance Are Associated With the Affective Impact of Odor, but Not With Smell Test Results.

Our aim was to explore factors potentially associated with subjective (self-rated) and objective (measured using the Sniffin' Sticks Extended test) olfactory performance in the general population without olfactory disorders. We studied associations between olfactory performance and how important odors were in determining liking for new places, things, and people (measured using the Affective Impact of Odor scale) and the average annoyance caused by odors in 117 adults (83 women, 34 men; age 18-69 years, mean age 32 years). In a subset of 44 participants, we also studied associations between olfactory performance and spice odor identification task scores (14 odors) and the number of herbs and spices consumed. Self-rated olfactory acuity and odor-related annoyance were associated with the Affective Impact of Odor scores, but neither correlated with the smell test results. Instead, the number of spices consumed correlated with spice odor identification score ( r = .50) and the identification (but not threshold nor discrimination) subscore of the Sniffin' Sticks test ( r = .49). Our results suggest that a tendency to perceive odors in affective terms may be associated with overestimation of olfactory abilities and that recurrent exposure to a large variety of spice odors may improve performance on odor identification.

Improved cider fermentation performance and quality with newly generated Saccharomyces cerevisiae × Saccharomyces eubayanus hybrids.

Yeast cryotolerance may be advantageous for cider making, where low temperatures are usually employed. Here, we crossed the cryotolerant S. eubayanus with a S. cerevisiae wine strain and assessed the suitability of the hybrids for low-temperature cider fermentation. All strains fermented the juice to 5% ABV, but at different rates; hybrid strains outperformed S. cerevisiae, which was sensitive to low temperatures. The best hybrid fermented similarly to S. eubayanus. S. eubayanus produced sulphurous off flavours which masked a high concentration of fruity ester notes. This phenotype was absent in the hybrid strains, resulting in distinctly fruitier ciders. Aroma was assessed by an independent consumer panel, which rated the hybrid ciders as identical to the wine strain cider. Both were significantly more pleasant than the S. eubayanus cider. Interspecific hybridization can apparently be used effectively to improve low-temperature fermentation performance without compromising product quality.

Pleasantness, familiarity, and identification of spice odors are interrelated and enhanced by consumption of herbs and food neophilia.

The primary dimension of odor is pleasantness, which is associated with a multitude of factors. We investigated how the pleasantness, familiarity, and identification of spice odors were associated with each other and with the use of the respective spice, overall use of herbs, and level of food neophobia. A total of 126 adults (93 women, 33 men; age 25-61 years, mean 39 years) rated the odors from 12 spices (oregano, anise, rosemary, mint, caraway, sage, thyme, cinnamon, fennel, marjoram, garlic, and clove) for pleasantness and familiarity, and completed a multiple-choice odor identification. Data on the use of specific spices, overall use of herbs, and Food Neophobia Scale score were collected using an online questionnaire. Familiar odors were mostly rated as pleasant (except garlic), whereas unfamiliar odors were rated as neutral (r = 0.63). We observed consistent and often significant trends that suggested the odor pleasantness and familiarity were positively associated with the correct odor identification, consumption of the respective spice, overall use of herbs, and food neophilia. Our results suggest that knowledge acquisition through repetitive exposure to spice odor with active attention may gradually increase the odor pleasantness within the framework set by the chemical characteristics of the aroma compound.

Raspberry wine fermentation with suspended and immobilized yeast cells of two strains of Saccharomyces cerevisiae.

The objectives of this study were to assess the differences in fermentative behaviour of two different strains of Saccharomyces cerevisiae (EC1118 and RC212) and to determine the differences in composition and sensory properties of raspberry wines fermented with immobilized and suspended yeast cells of both strains at 15 °C. Analyses of aroma compounds, glycerol, acetic acid and ethanol, as well as the kinetics of fermentation and a sensory evaluation of the wines, were performed. All fermentations with immobilized yeast cells had a shorter lag phase and faster utilization of sugars and ethanol production than those fermented with suspended cells. Slower fermentation kinetics were observed in all the samples that were fermented with strain RC212 (suspended and immobilized) than in samples fermented with strain EC1118. Significantly higher amounts of acetic acid were detected in all samples fermented with strain RC212 than in those fermented with strain EC1118 (0.282 and 0.602 g/l, respectively). Slightly higher amounts of glycerol were observed in samples fermented with strain EC1118 than in those fermented with strain RC212.

Process engineering for bioflavour production with metabolically active yeasts - a mini-review.

Flavours are biologically active molecules of large commercial interest in the food, cosmetics, detergent and pharmaceutical industries. The production of flavours can take place by either extraction from plant materials, chemical synthesis, biological conversion of precursor molecules or de novo biosynthesis. The latter alternatives are gaining importance through the rapidly growing fields of systems biology and metabolic engineering, giving efficient production hosts for the so-called 'bioflavours', which are natural flavour and/or fragrance compounds obtained with cell factories or enzymatic systems. Yeasts are potential production hosts for bioflavours. In this mini-review, we give an overview of bioflavour production in yeasts from the process-engineering perspective. Two specific examples, production of 2-phenylethanol and vanillin, are used to illustrate the process challenges and strategies used.

Food neophobia associates with lower dietary quality and higher BMI in Finnish adults.

OBJECTIVE: Food neophobia has been associated with decreased consumption of vegetables mainly among children. We hypothesized that food neophobia in adults is also associated with lower overall dietary quality and higher BMI. DESIGN: Data for the present cross-sectional analyses were derived from parents in a follow-up family study. SETTING: The STEPS study, a longitudinal study of health and development of a cohort of children born in south-west Finland. SUBJECTS: The parents, 1178 women (age 19-45 years, mean 32·2 years) and 1013 men (age 18-57 years, mean 34·1 years), completed a questionnaire at home when their child was 13 months old. The questionnaire included the Food Neophobia Scale (FNS; range 10-70), the Index of Diet Quality (IDQ; range 0-16) and a measure of fruit and vegetable consumption. At that time the participants' height and weight were also measured by a research nurse to calculate BMI. RESULTS: Compared with the food neophilics (FNS score 10-24), the food neophobics (FNS score 40-70) consumed fewer vegetables (women: 15 v. 10 portions/week; men: 13 v. 7 portions/week), scored lower on the IDQ (women: 9·7 v. 8·5; men: 8·8 v. 7·8) and had higher BMI (women: 24·2 v. 26·0 kg/m²; men: 26·5 v. 27·5 kg/m²) as tested by one-way ANOVA, with all P values <0·001 in women and <0·05 in men. The food neophobics followed a diet lower in nutritional quality than did the food neophilics, especially regarding vegetables. CONCLUSIONS: Food neophobia may complicate adaptation to dietary recommendations and predispose to overweight.

Sensory and Physical Properties of Fibrous Meat Analogs Made from Faba Bean, Pea, and Oat Using High-Moisture Extrusion.

Faba bean is a promising source of ingredients for the production of meat analogs. However, sensory properties of faba bean, especially the bitter taste of the protein concentrate, restrict its use. Our aim was to assess the feasibility of two types of faba bean ingredients-flour (from germinated, gently heat-treated beans) and groat (from non-germinated, roasted beans)-in combination with pea protein isolate and oat fiber concentrate for producing meat analogs using high-moisture extrusion. We produced six samples using varying recipes, while maintaining constant process parameters. An untrained panel (55 participants) evaluated the samples for key sensory attributes (check-all-that-apply) and rated their pleasantness. The water absorption capacity and mechanical properties of the samples were assessed using instrumental measurements. The samples were frequently described as 'beany' and 'tasteless', but very rarely as 'bitter'. The most frequently cited attributes for mouthfeel varied between the samples containing 30% ('tough', 'gummy') and 50% ('crumbly', 'floury') of faba bean flour/groat and were associated with corresponding mechanical properties. On average, the sample containing a blend of faba bean groat and pea protein isolate (50% each) appeared to be the most pleasant. Our results suggest that faba bean groat with pea protein isolate enables the production of fibrous meat analogs with acceptable taste and texture, without the bitter off-taste.

Fuzzy liquid analysis by an array of nonspecifically interacting reagents: the taste of fluorescence.

Complex or unknown liquid analysis requires extensive instrumentation and laboratory work; simple field devices usually have serious limitations in functionality, sensitivity, and applicability. This communication presents a novel, effective, and simple approach to fingerprinting liquids. The method is based on nonspecific interactions of the sample liquid, a long lifetime luminescent europium label, and various surface modulators in an array form that is readily converted to a field analysis µTAS system. As compared to existing e-nose or e-tongue techniques, the method is unique both in terms of sensitivity and usability, mainly due to the well-known unique properties of the europium label. This communication demonstrates the use of this new method in distinguishing different wines, waters, alcohols, and artificially modified berry juices.

Explaining and predicting individually experienced liking of berry fractions by the hTAS2R38 taste receptor genotype.

The roles of taste and astringent properties, food choice motives and health concerns in liking of bilberry and crowberry samples were studied using a sensory panel prescreened for the hTAS2R38 taste receptor genotype. The subjects rated the intensity of sourness, bitterness and two astringent properties (soft, velvety and rough, puckering) of all berry samples. They also scored the liking of juice fractions and completed a food choice motive and health concern questionnaire. Regression models were used to combine different data sets and to predict liking of the extracts. Sourness contributed positively to the liking of berry fractions, and bitterness and rough astringency were negative factors. The hTAS2R38 genotype affected the liking of polyphenol-rich extracts, which were significantly bitter and astringent. Based on the genotype grouping of subjects, PAV homozygotes gave lower ratings to the attributes than AVI homozygotes. In contrast, PAV homozygotes were predicted to dislike the extracts notably more than AVI homozygotes. Health concern and food choice motives related to health and weight control had significant roles in individual liking of juice fractions. Our results indicate that mood was more important to the PAV homozygotes than to the AVI homozygotes.

Factors explaining individual differences in the oral perception of capsaicin, l-menthol, and aluminum ammonium sulfate.

This research focused on the oral perception of naturally occurring chemical food compounds that are used in the pharma and food industries due to their pharmacological properties. They stimulate chemically sensitive receptors of the somatosensory system and are also chemesthetic compounds. Capsaicin is a naturally occurring alkaloid activating pungency perception. l-Menthol is a cyclic monoterpene working also as a medical cooling agent. Aluminum ammonium sulfate is used as a dehydrating agent and additive known to activate astringency in oral cavity. The objective of the study was to identify factors explaining individual differences in the perception of oral chemesthesis measured as sensitivity to chemesthetic compounds and their recognition. The subjects (N = 205) evaluated quality-specific prototypic compounds at five different concentration levels. Differences between gender were discovered in capsaicin sensitivity with men being less sensitive than women. Age was associated with the perception of capsaicin, l-menthol, aluminum ammonium sulfate, and the combined oral chemesthetic sensitivity. Quality-specific recognition ratings were also contributing to the sensitivity to chemesthetic compounds. A combined oral chemesthetic recognition score was created based on quality-specific recognition ratings. Increasing age generally indicated weaker recognition skills. Better recognizers had a higher combined oral chemesthetic sensitivity score than poorer recognizers. These results provide new information about chemesthesis. The results suggest that age and gender are important factors in explaining individual differences in sensitivity to capsaicin, l-menthol, and aluminum ammonium sulfate. In addition, recognition skills are associated with the sensitivity based on the quality-specific recognition scores.

Food-related consumer behaviours in times of crisis: Changes in the wake of the Ukraine war, rising prices and the aftermath of the COVID-19 pandemic.

When the COVID-19 pandemic subsided, the war in Ukraine led to further disruptions in consumers' daily behaviours, with rising prices for food and energy. We conducted a survey study on self-reported changes in food-related consumer behaviour in ten European countries and compared the results to a similar study conducted two years ago. A latent class cluster analysis distinguished five clusters and showed that different types of consumers can be distinguished based on how they react to the crisis as regards their eating habits. 19% of survey participants reported no major changes, and 32% reported changes mostly in terms of more price sensitivity. Among those that reported changes beyond reacting to higher prices, there are indications of more mindful eating and more deliberate choices. The changes already found earlier in response to the COVID-19 pandemic therefore seem to have been strengthened and supplemented by reactions to price increases. The results present a challenge to the food industry in terms of supplying healthy and sustainable food at affordable prices.

Nutrition economics: towards comprehensive understanding of the benefits of nutrition.

There has been an increase in the knowledge and interest on nutrition, and functional foods have gained popularity over the last few decades, and the trend is increasing. Probiotics and prebiotics are among the most studied functional foods. Nutrition economics has been defined as the discipline dedicated to researching and characterising health and economic outcomes in nutrition for the benefit of society. The concept and its application to probiotics and prebiotics will be discussed in terms of health and economic benefits and their evaluation. Health economics and concrete applications showing how to maximise long-term nutritional benefits will contribute to motivate consumers in making food choices based on a rational understanding of their own interest. We present a model that shows that nutrition economics can be used as an analytical tool for product and service network development.