Relation between sweet food consumption and liking for sweet taste in French children

Genome-wide variants and optimal allelic combinations for citric acid in tomato

Citric acid (CA) plays a crucial role as a fruit flavor enhancer and serves as a mediator in multiple metabolic pathways in tomato fruit development. Understanding factors influencing CA metabolism is essential for enhancing fruit flavor and CA-mediated biological processes. The accumulation of CA, however, is influenced by a complex interplay of genetic and environmental factors, leading to challenges in accurately predicting and regulating its levels. In this study, we conducted a genome-wide association study (GWAS) on CA, employing six landmark models based on genome-wide variations including structural variants, insertions and deletions, and single nucleotide polymorphisms. The identification of 11 high-confidence candidate genes was further facilitated by leveraging linkage disequilibrium and causal variants associated with CA. The transcriptome data from candidate genes were examined, revealing higher correlations between the expression of certain candidate genes and changes in CA metabolism. Three CA-associated genes exerted a positive regulatory effect on CA accumulation, while the remaining genes exhibited negative impacts based on gene cluster and correlation analyses. The CA content of tomatoes is primarily influenced by improvement sweeps with minimal influence from domestication sweeps in the long-term breeding history, as evidenced by population differentiation and variants distribution. The presence of various causal variants within candidate genes is implicated in the heterogeneity of CA content observed among the tomato accessions. This observation suggests a potential correlation between the number of alternative alleles and CA content. This study offers significant function-based markers that can be utilized in marker-assisted breeding, thereby enhancing their value and applicability.

Chronic sugar exposure increases daily intake of sugars but decreases avidity for sweeteners in mice

Little is known about how chronic sugar consumption impacts avidity for and daily intake of sugars. This issue is topical because modern humans exhibit high daily intakes of sugar. Here, we exposed sugar-naïve C57BL/6 mice (across two 28-day exposure periods, EP1 and EP2) to a control (chow and water) or experimental (chow, water and a 11 or 34% sugar solution) diet. The sugar solutions contained sucrose, glucose syrups, or high-fructose syrups. We used brief-access tests to measure appetitive responses to sucralose and sucrose solutions at three time points: baseline (before EP1), after EP1, and after EP2. We used lick rates to infer palatability, and number of trials initiated/test to infer motivation. Exposure to the control diet had no impact on lick rates or number of trials initiated for sucralose and sucrose. In contrast, exposure to the experimental diets reduced licking for the sweeteners to varying degrees. Lick rates were reduced by exposure to sugar solutions containing the 11% glucose syrups, 34% sucrose, 34% glucose syrups and 34% high-fructose syrups. The number of trials initiated was reduced by exposure to all of the sugar solutions. Despite the exposure-induced reductions in avidity for the sweetener solutions, daily intakes of virtually all of the sugar solutions increased across the exposure periods. We conclude that (i) chronic consumption of sugar solutions reduced avidity for the sweetened solutions, (ii) the extent of this effect depended on the concentration and type of sugar, and (iii) avidity for sweet-tasting solutions could not explain the persistently high daily intake of sugar solutions in mice.

Study protocol of the sweet tooth study, randomized controlled trial with partial food provision on the effect of low, regular and high dietary sweetness exposure on sweetness preferences in Dutch adults

BACKGROUND

Several health organizations recommend lowering the consumption of sweet-tasting foods. The rationale behind this recommendation is that a lower exposure to sweet foods may reduce preferences for sweet tasting foods, thus lowering sugar and energy intake, and in turn aiding in obesity prevention. However, empirical data supporting this narrative are lacking. In fact, relatively little is known about the contribution of long-term sweet taste exposure on one's sweetness preferences.

METHODS

The primary objective of this randomized controlled trial is to assess the effect of low, regular and high dietary sweetness exposure on preference for sweet foods and beverages, and to compare these effects between intervention groups. One hundred and eighty adults aged 18-65 years with a BMI of 18.5-30.0 kg/m² will be recruited and randomly allocated to either: low dietary sweetness exposure (LSE) (10-15% daily energy from sweet tasting foods), regular dietary sweetness exposure (RSE) (25-30% daily energy from sweet tasting foods), or high dietary sweetness exposure (HSE) (40-45% daily energy from sweet tasting foods), for 6 months, followed by a 4-month follow up. Intervention foods are provided ad libitum, covering approximately 50% of the daily number of food items, to include sugar-sweetened, low-calorie-sweetener-sweetened and non-sweet foods. The primary outcome measure is the difference in change in sweetness preference from baseline to 6 months between intervention groups. Secondary outcomes include: change in sweet taste preferences at different time-points; taste intensity perception; behavioral outcomes: food choice and intake, sweet-liker type, food cravings, dietary taste preferences and dietary taste patterns; anthropometric outcomes: body composition, waist-hip circumference, body weight; and biochemical outcomes: glucose variability and biomarkers related to CVD and diabetes.

DISCUSSION

This study will generate important data on the effect of dietary sweetness exposure on sweetness preferences in terms of effect size and change, duration of change and its impact on food intake, body weight status and associated health outcomes.

TRIAL REGISTRATION

The study protocol has been registered on ClinicalTrials.gov (ID no. NCT04497974, Registered 4 August 2020, https://clinicaltrials.gov/ct2/show/NCT04497974 ) and approved by Wageningen's Medical Ethical Committee (ABR no. NL72134).

Probiotic dairy products and consumption preferences in terms of sweetness sensitivity and the occurrence of childhood obesity

Fermented dairy products such as yogurt contain many bioactive compounds. In addition, probiotic yogurts are an invaluable source of probiotic bacteria and are a group of probiotic products best accepted by children. There is plenty of research indicating an interdependence between yogurt consumption, body mass index, and adipose tissue percentage, which suggests that yogurt consumption may contribute to reducing the risk of becoming overweight or obese. In turn, the occurrence of overweight and obesity may be accompanied by a reduced sensitivity to sweetness, which modifies food preference selection and acceptance, including with yogurt. This study aimed to assess the preferences and consumption of yogurt in terms of sensitivity to recognize sweetness and obesity in a group of 7–9-year-old children. Body mass index and adipose tissue percentage obesity indicators were determined, and the frequency of fermented milk product consumption was assessed about the results of the sweetness recognition test as well as yogurt preferences. There was no significant relationship between body weight and the frequency of fermented milk product consumption. Correlations were found between the values of body mass index and the ability to recognize sweetness, which was significantly better recognized by underweight children or at normal body weight, moreover, those children with a higher ability to recognize sweetness significantly more frequently preferred plain unsweetened yogurt.

The sweet tooth of infancy: Is sweetness exposure related to sweetness liking in infants up to 12 months of age?

Infants become increasingly exposed to sweet-tasting foods in their first year of life. However, it is still unclear whether repeated exposure to sweet taste is linked to infants' sweetness liking during this period. Making use of data from the OPALINE cohort, this study aimed to examine the link between sweetness exposure and sweetness liking during two important periods in early infant feeding: at the start of complementary feeding (3-6 months) and the transition to the family table (10-12 months). Infants' sweetness exposure was assessed using 7-d food records which were completed by mothers every month (n 312), reporting daily consumption rates of formula/breast milk or complementary food and the type of formula milk and/or complementary foods for each feeding occasion. Infants' sweetness liking was studied in the laboratory at 3, 6 and 12 months of age by assessing their response to a lactose-water solution and the amount drunk of this solution compared with plain water. Linear regressions and structural equation model assessed associations between exposure to and liking for sweetness at 6 and 12 months. Neither at 6 (n 182) nor at 12 months (n 197) was sweetness exposure associated with sweetness liking. While sweetness liking at 3 months was unrelated to liking at 6 months, the latter predicted sweetness liking at 12 months. These findings demonstrate no association between sweetness exposure at 3 to 12 months and liking at 6 and 12 months despite a sharp increase in sweetness exposure in that period. However, sweetness liking at 6 and 12 months was positively associated.

Harnessing Food Product Reviews for Personalizing Sweetness Levels

Sweet taste is innately appealing, ensuring that mammals are attracted to the sweetness of mother’s milk and other sources of carbohydrates and calories. In the modern world, the availability of sugars and sweeteners and the eagerness of the food industry to maximize palatability, result in an abundance of sweet food products, which poses a major health challenge. The aim of the current study is to analyze sweetness levels, liking, and ingredients of online reviews of food products, in order to obtain insights into sensory nutrition and to identify new opportunities for reconciling the palatability–healthiness tension. We collected over 200,000 reviews of ~30,000 products on Amazon dated from 2002 to 2012 and ~350,000 reviews of ~2400 products on iHerb from 2006 to 2021. The reviews were classified and analyzed using manual curation, natural language processing, and machine learning. In total, ~32,000 (Amazon) and ~29,000 (iHerb) of these reviews mention sweetness, with 2200 and 4600 reviews referring to the purchased products as oversweet. Oversweet reviews were dispersed among consumers. Products that included sucralose had more oversweet reviews than average. 26 products had at least 50 reviews for which at least 10% were oversweet. For these products, the average liking by consumers reporting oversweetness was significantly lower (by 0.9 stars on average on a 1 to 5 stars scale) than by the rest of the consumers. In summary, oversweetness appears in 7–16% of the sweetness-related reviews and is less liked, which suggests an opportunity for customized products with reduced sweetness. These products will be simultaneously healthier and tastier for a substantial subgroup of customers and will benefit the manufacturer by expanding the products’ target audience. Analysis of consumers’ reviews of marketed food products offers new ways to obtain informative sensory data.

Sweetness of Chilean Infants' Diets: Methodology and Description

Sugars and other sweeteners contribute to the sweet taste of foods; exposure to this taste could alter appetite regulation and preferences for sweet products. Despite this, there is no widely accepted methodology for estimating overall diet sweetness. The objective of this study was to develop a methodology to estimate diet sweetness and describe diet sweetness in a cohort of Chilean infants. In order to estimate diet sweetness density, the sweetness intensity of foods was obtained from existing databases and from sensory evaluations in products with no available information and then linked to 24-h dietary recalls of infants at 12 and 36 months of age. Diet sweetness density was significantly and positively associated with total sugars and non-nutritive sweeteners intakes. The main food sources of sweetness at 12 months were fruits (27%) and beverages (19%). Sweetness density increased 40% between 12 and 36 months (from 1196 to 1673, p < 0.01), and sweetness density at both ages was significantly associated. At 36 months, beverages and dairy products were the main sources of sweetness (representing 32.2% and 28.6%, respectively). The methodology presented here to estimate the sweetness density of the diet could be useful for other studies to help elucidate different effects of exposure to high sweetness.

Finding the Sweet Spot: Measurement, Modification, and Application of Sweet Hedonics in Humans

Sweetness is a sensation that contributes to the palatability of foods, which is the primary driver of food choice. Thus, understanding how to measure the appeal (hedonics) of sweetness and how to modify it are key to effecting dietary change for health. Sweet hedonics is multidimensional so can only be captured by multiple approaches including assessment of elements such as liking, preference, and consumption intent. There are both innate and learned components to the appeal of sweet foods and beverages. These are responsive to various behavioral and biological factors, suggesting the opportunity to modify intake. Given the high amount of added sugar intake in the United States and recommendations from many groups to reduce this, further exploration of current hypothesized approaches to moderate sugar intake (e.g., induced hedonic shift, use of low-calorie sweeteners) is warranted.

Associations between Infant Dietary Intakes and Liking for Sweetness and Fattiness Sensations in 8-to-12-Year-Old Children

An exposure to sweetened and fatty foods early in life may be involved in high liking later in life. The objective is to investigate the association between dietary exposure to carbohydrate, sugars and fat in infancy, with liking for sweetness, fattiness and fattiness-and-sweetness sensations at 8-to-12-year-old. Analyses were conducted on 759 French children from the EDEN mother-child cohort. Carbohydrate, sugar or fat intake, being a consumer of added sugars or added fats were assessed at 8 and 12 months using 3-day food records. The liking score (0–10) for the different sensations was assessed through an online child-completed questionnaire. Associations were tested by linear regressions adjusted for main confounders and the interaction with sex was tested. None of the early dietary exposure variables was related to fattiness liking. Carbohydrate intake at 8 months was positively but weakly associated with liking for sweetness-and-fattiness. In girls only, carbohydrate intake at 12 months was positively associated with liking for sweetness. Globally, no marked associations were observed between infant dietary exposure to sweet and fat and liking for sweetness and fattiness in young children. The positive link in girls between early carbohydrate exposure and later liking for sweetness needs to be confirmed in further studies.

Probiotic fermented milks: Children's emotional responses using a product-specific emoji list

This study aimed to develop and validate a product-specific emoji list and use this list to analyse children's emotional responses associated with the consumption of probiotic fermented milks prepared with different probiotic strains. Furthermore, the overall liking of the products was studied during a sensory test. Six formulations were studied: Bifidobacterium BB12 (BB), Lactobacillus acidophilus L3 (LA3), Lactobacillus acidophilus LA 05 (LA5), Lactobacillus delbrueckii subsp. lactis (LL), Lacticaseibacillus casei 01 (LC), and Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus (CONV). A total of 132 children (7-14 years old) participated in two study phases: development (n = 32) and validation (n = 100) of the list. Fifteen emoji were selected to be included in the product-specific list, which had a high frequency of citations in the first phase. The formulations with the highest overall liking (LL, BB, LC and CONV) were correlated with positive emoji, while the least-liked formulations (LA3 and LA5) were associated with negative emoji. Furthermore, the utilisation of emoji enabled the differentiation among formulations with similar overall liking. Therefore, this study developed and validated an emoji list to be used in the evaluation of fermented milks by children. The results suggest that the type of probiotic culture impacted the sensory characteristics of fermented milks, supporting the use of Bifidobacterium, L. lactis or L. casei in these products.

Texture Preferences of Chinese, Korean and US Consumers: A Case Study with Apple and Pear Dried Fruits

The present study aimed to understand the drivers of liking dried apple and pear chips with various textures among Chinese (n = 58), Korean (n = 58), and US (n = 56) consumers. The possibility of hedonic transfer from snack texture preferences to fruit-chip texture preferences was also investigated among Chinese and Koreans. Fourteen fruit-chip samples with four textural properties (crispy, puffy, soft, and jelly-like) were selected. Consumers rated their level of liking for each sample, and then they performed hedonic-based projective mapping with the same samples. In the hedonic texture transfer investigation, consumers rated their acceptance of nine snacks with various textures but possessing similar textures to those of dried fruit samples. The data were analyzed by ANOVA and multiple factor analysis. Most consumers disliked samples with a soft or jelly-like texture, while liked samples with a crispy texture. Cross-cultural differences were observed in the liking of puffy samples, with both Chinese and Koreans liking puffy samples as much as crispy ones for their melting characteristics in the mouth, while US consumers perceived the puffy samples as being Styrofoam-like and disliked them. Hedonic transfer was observed from snack texture preferences to fruit-chip. Individual texture preferences for snacks seem to significantly affect the texture preferences for fruit chips.

Determinants of Sweetness Preference: A Scoping Review of Human Studies

Factors associated with sweetness preference are multi-faceted and incredibly complex. A scoping review was undertaken to identify determinants of sweetness preference in humans. Using an online search tool, ProQuest ™, a total of 99 publications were identified and subsequently grouped into the following categories of determinants: Age, dietary factors, reproductive hormonal factors, body weight status, heritable, weight loss, sound, personality, ethnicity and lifestyle, previous exposure, disease, and 'other' determinants. Methodologies amongst studies were heterogenous in nature (e.g., there was variability across studies in the sweetness concentrations tested, the number of different sweetness concentrations used to assess sweetness preference, and the methods utilized to measure sweetness preference), rendering interpretation of overall findings challenging; however, for certain determinants, the evidence appeared to support predictive capacity of greater sweetness preference, such as age during certain life-stages (i.e., young and old), being in a hungry versus satiated state, and heritable factors (e.g., similar sweetness preferences amongst family members). Recommendations for the design of future studies on sweetness preference determinants are provided herein, including an "investigator checklist" of criteria to consider.

Early influencing factors on the development of sensory and food preferences

PURPOSE OF REVIEW

The current review focuses on studies investigating the factors related to the development of preferences for foods and sensory inputs (tastes, odours, and food textures) in the first years of life, which constitutes a specific window for food learning.

RECENT FINDINGS

Foetal nutrition, intrauterine growth, and prematurity influence food preferences; this topic warrants more research to broaden our understanding of the 1000 days phenomenon. Although it is less studied than other sensory inputs, food texture acceptance, and the related sensitive period for texture introduction are attracting more attention, as is the impact of fat acceptance. Research should focus not on vegetables alone but on diverse foods whose consumption is encouraged (e.g., fishes and legumes). The role of parental feeding practices, as another major determinant, continues to inspire research exploring the bidirectional influences between children and caregivers. New interventions have confirmed the strong positive influence of repeated exposure to foods through familiarization via taste lessons, cooking, or play activities on acceptance. Interventions that consider individuals traits are necessary.

SUMMARY

Although new evidence is available, it remains a challenge to consider both individual traits and bidirectional influences between parents and children and to investigate this issue worldwide and in all socioeconomic status groups.

A new sensory sweetness definition and sweetness conversion method of five natural sugars, based on the Weber-Fechner Law

This study's aim is to establish a new sensory sweetness definition and conversion method for five sugars. A "closed-type" question based on triangle test and paired comparison was used for sensory evaluation. The absolute threshold and nine sensory difference threshold values were determined and used to generate a sweet sensory difference strength curve. Defining absolute threshold of sucrose sweetness as 1, the sucrose sweetness at any concentration could be calculated via the curve. After taking the logarithm of each curve, sweetness index was calculated as 1, 1.12, 0.94, 1.29, and 1.25 for sucrose, glucose, fructose, lactose and maltose, respectively. Based on this, each sugar concentration and sweetness could be converted and calculated. Single sugar and mixed-sugars sweetness comparison experiments verified the new sweetness index and sweetness values were more accurate (83.3-100%) than those reported in previous studies. Therefore, this new definition and conversion method established more reliable references for sweet taste sensory applications.

Association between early introduction of fruit juice during infancy and childhood consumption of sweet-tasting foods and beverages among children exposed and unexposed to gestational diabetes mellitus in utero

BACKGROUND

Children exposed to gestational diabetes mellitus (GDM) in utero are at high-risk of obesity. Given that nutritional habits can track from infancy to childhood, the aim of this study was to evaluate the association between the timing of fruit juice introduction in infancy and later consumption of sweet-tasting foods and beverages among children exposed (GDM+) and unexposed (GDM-) to GDM.

METHODS

A total of 107 GDM+ and 59 GDM- participated in the project. Data on the timing of fruit juice introduction during infancy were retrospectively collected for 62 GDM+ and 32 GDM- children. Current dietary intakes were collected with two 24-hour dietary recall questionnaires. Children were divided into groups according to the median timing of juice introduction (9 months).

RESULTS

Mean age of children was 6.3 ± 2.6 and 7.6 ± 3.7 years for GDM+ and GDM- children, respectively (p = 0.08). Mean age of fruit juice introduction was similar between groups (p > 0.05). Consuming >1 serving of fruit juice per day was 2.72 times more prevalent among GDM+ children introduced to fruit juice <9 months, compared to GDM+ children introduced ≥9 months (CI: 1.19-6.20). This association was not observed in the GDM- group. The timing of fruit juice introduction was not associated with later consumption of sweets, desserts and sweet-tasting beverages when adjustment for children's age was made among GDM+ and GDM- children.

CONCLUSION

Early introduction of fruit juice in infant diet is associated with higher prevalence of consumption of >1 serving of fruit juice per day in GDM+ children.

A Broad-Spectrum Sweet Taste Sensor Based on Ni(OH)₂/Ni Electrode

A broad-spectrum sweet taste sensor based on Ni(OH)₂/Ni electrode was fabricated by the cyclic voltammetry technique. This sensor can be directly used to detect natural sweet substances in 0.1 M NaOH solution by chronoamperometry method. The current value measured by the sensor shows a linear relationship with the concentration of glucose, sucrose, fructose, maltose, lactose, xylitol, sorbitol, and erythritol (R² = 0.998, 0.983, 0.999, 0.989, 0.985, 0.990, 0.991, and 0.985, respectively). Moreover, the characteristic value of this sensor is well correlated with the concentration and relative sweetness of eight sweet substances. The good correlation between the characteristic value of six fruit samples measured by the sensor and human sensory sweetness measured by sensory evaluation (correlation coefficient = 0.95) indicates that it can reflect the sweetness of fruits containing several sweet substances. In addition, the sensor also exhibits good long-term stability over 40 days (signal ratio fluctuation ranges from 91.5% to 116.2%). Thus, this broad-spectrum sensor is promising for sweet taste sensory application.

The development of basic taste sensitivity and preferences in children

This study aims at understanding how preference and sensitivity to the basic tastes develop in the preschool years, and how the two relate to each other. To expand on the existing literature regarding taste preferences conducted in cross-sectional studies, a longitudinal design was applied with children from age four to six years old. During the springs of 2015, 2016, and 2017, 131 children born in 2011 were tested in their kindergartens. To investigate preferences for sweet, sour and bitter tastes, the children performed ranking-by-elimination procedures on fruit-flavored beverages and chocolates with three taste intensity levels. The beverages varied in either sucrose, citric acid, or the bitter component isolone. The chocolates varied in the bitter component theobromine from cocoa and sucrose content. Each year, the children also performed paired-comparison tasks opposing plain water to tastant dilutions at four concentrations. The stimuli consisted of the five basic tastes: sweet (sucrose) sour (citric acid monohydrate) umami (monosodium glutamate), salty (sodium chloride), and bitter (quinine hydrochloride dihydrate). Preference for sweetness levels increased with age, while preference for bitterness and sourness levels were stable. Concerning taste sensitivity, the children showed an increase in sensitivity for sourness and saltiness, a decrease for sweetness, and stability for umami and bitterness. A negative association was found between sweetness sensitivity and preference for sweetness. The study highlights different trajectories of sensitivity and preferences across tastes. On average, a reduction in sweetness sensitivity combined with an increase in preference for higher sweetness was observed from the age of four to six. The weak relationship between taste sensitivity and taste preference in our data suggests that taste preference development is shaped by a multitude of factors in addition to taste sensitivity.

A workshop on 'Dietary Sweetness-Is It an Issue?'

This report summarises a workshop convened by ILSI Europe on 3 and 4 April 2017 to discuss the issue of dietary sweetness. The objectives were to understand the roles of sweetness in the diet, establish whether exposure to sweetness affects diet quality and energy intake, and consider whether sweetness per se affects health. Although there may be evidence for tracking of intake of some sweet components of the diet through childhood, evidence for tracking of whole diet sweetness, or through other stages of maturity are lacking. The evidence to date does not support adverse effects of sweetness on diet quality or energy intake, except where sweet food choices increase intake of free sugars. There is some evidence for improvements in diet quality and reduced energy intake where sweetness without calories replaces sweetness with calories. There is a need to understand the physiological and metabolic relevance of sweet taste receptors on the tongue, in the gut and elsewhere in the body, as well as possible differentiation in the effects of sustained consumption of individual sweeteners. Despite a plethora of studies, there is no consistent evidence for an association of sweetness sensitivity/preference with obesity or type 2 diabetes. A multifaceted integrated approach, characterising nutritive and sensory aspects of the whole diet or dietary patterns, may be more valuable in providing contextual insight. The outcomes of the workshop could be used as a scientific basis to inform the expert community and create more useful dialogue among health care professionals.