Analysis of Volatile Compounds in Processed Cream Cheese Models for the Prediction of "Fresh Cream" Aroma Perception.

Controlling flavor perception by analyzing volatile and taste compounds is a key challenge for food industries, as flavor is the result of a complex mix of components. Machine-learning methodologies are already used to predict odor perception, but they are used to a lesser extent to predict aroma perception. The objectives of this work were, for the processed cream cheese models studied, to (1) analyze the impact of the composition and process on the sensory perception and VOC release and (2) predict "fresh cream" aroma perception from the VOC characteristics. Sixteen processed cream cheese models were produced according to a three-factor experimental design: the texturing agent type (κ-carrageenan, agar-agar) and level and the heating time. A R-A-T-A test on 59 consumers was carried out to describe the sensory perception of the cheese models. VOC release from the cheese model boli during swallowing was investigated with an in vitro masticator (Oniris device patent), followed by HS-SPME-GC-(ToF)MS analysis. Regression trees and random forests were used to predict "fresh cream" aroma perception, i.e., one of the main drivers of liking of processed cheeses, from the VOC release during swallowing. Agar-agar cheese models were perceived as having a "milk" odor and favored the release of a greater number of VOCs; κ-carrageenan samples were perceived as having a "granular" and "brittle" texture and a "salty" and "sour" taste and displayed a VOC retention capacity. Heating induced firmer cheese models and promoted Maillard VOCs responsible for "cooked" and "chemical" aroma perceptions. Octa-3,5-dien-2-one and octane-2,3-dione were the two main VOCs that contributed positively to the "fresh cream" aroma perception. Thus, regression trees and random forests are powerful statistical tools to provide a first insight into predicting the aroma of cheese models based on VOC characteristics.

Vitamin B4 as a salt substitute in bread: A challenging and successful new strategy. Sensory perception and acceptability by French consumers.

Numerous scientific studies have shown that overconsumption of salt can be harmful and promotes the development of cardiovascular diseases. For this reason, many international organizations and government agencies aim to reduce overall salt consumption from food. Recent exploratory work has shown that vitamin B4 can play the role of salt substitute. This study aims on the one hand to develop and optimize a bread recipe reduced in salt and enriched with vitamin B4. On the other, it aims to study the acceptability for consumers of this double innovation, combining the addition and withdrawal of a nutrient. The study was conducted with French consumers. The sensory test showed that vitamin B4 tends to increase the perception of salt in salt-reduced bread. The acceptance of reduced-salt and vitamin B4-enriched bread was investigated in three focus-groups, mixing blind tests, information input and spontaneous evocations. Three potential targets have been identified: health-oriented young people, young parents who want to educate children to engage in a healthy lifestyle, and people broadly sensitive to nutritional information. Consumers with a pleasure and taste-oriented profile were more skeptical of the new bread formula because of greater attachment to traditional, salty French bread.

Influence of baking time and formulation of part-baked wheat sourdough bread on the physical characteristics, sensory quality, glycaemic index and appetite sensations.

Raw materials and process parameters in bread production can modulate the glycemic index, which on itself has been linked with provision of better hunger satisfaction and maintaining better satiation. The objective of this research was to investigate if using unrefined wheat flour or the addition of intact cereals in formulation or alternating the baking time would have an effect on physical characteristics, sensory quality, glycaemic index and appetite sensations in wheat sourdough bread. In the study, three types of commercial part-baked frozen sourdough bread, baked to the final baking for two different times (long and short baking time) were used. A randomized controlled crossover trial was performed with 10 healthy adults who consumed sufficient quantity of bread to ingest 50 g available carbohydrates. Participants self-reported appetite sensations (desire to eat, hunger, fullness, satisfaction, appetite) on a 10 cm visual analog scale (VAS) scale in a course of 180 min. In addition, bread products were subjected to overall acceptability and different sensory attributes were examined on JAR "just about right" scale. Different bread formulations (refined flour, unrefined wheat flour, cereal flour or intact cereals) and different length of baking time significantly influenced (p < 0.005) physical, textural and sensory features of products. The alternation of aforementioned parameters decreased the glycemic index, but not significantly (p > 0.005). No correlation was found between lower GI, satiety and satiation. Liking score and incremental area under the curve (iAUC) of satiety and satiation were calculated as highest in sourdough bread with added cereals.

Comparison of Child and Adult Mastication of a Sticky Processed Cream Cheese and Simulation with a Masticator.

An advantage of masticators is the calibration and possible standardization of intra- and inter-individual mastication variability. However, mastication of soft, sticky and melting products, such as processed cream cheeses, is challenging to reproduce with a masticator. The objectives of this work were, for the cheese studied: (1) to compare child and adult mastication and (2) to find in vitro parameters which best reproduce their in vivo chewing. Five parameters influencing mastication (mouth volume, quantity consumed, saliva volume, mastication time and number of tongue-palate compressions) were measured in 30 children (5-12 years old) and 30 adults (18-65 years old) and compared between the two populations. They were then transposed to a masticator (Oniris device patent). The initial cheese, a homogeneous white paste, was surface-colored to investigate its in-mouth destructuring. In vivo boli were collected at three chewing stages (33, 66 and 99% of mastication time) and in vitro boli were obtained by varying the number of tongue-palate compressions and the rotation speed. In vivo and in vitro boli were compared by both image and texture analysis. Child masticatory parameters were proportionally smaller than those of adults. The in vivo child boli were less homogeneous and harder than adult ones. Comparison of in vivo and in vitro bolus color and texture enabled the successful determination of two in vitro settings that closely represented the mastication of the two populations studied.

Acute and two-week effects of neotame, stevia rebaudioside M and sucrose-sweetened biscuits on postprandial appetite and endocrine response in adults with overweight/obesity-a randomised crossover trial from the SWEET consortium.

BACKGROUND: Sweeteners and sweetness enhancers (S&SE) are used to replace energy yielding sugars and maintain sweet taste in a wide range of products, but controversy exists about their effects on appetite and endocrine responses in reduced or no added sugar solid foods. The aim of the current study was to evaluate the acute (1 day) and repeated (two-week daily) ingestive effects of 2 S&SE vs. sucrose formulations of biscuit with fruit filling on appetite and endocrine responses in adults with overweight and obesity. METHODS: In a randomised crossover trial, 53 healthy adults (33 female, 20 male) with overweight/obesity in England and France consumed biscuits with fruit filling containing 1) sucrose, or reformulated with either 2) Stevia Rebaudioside M (StRebM) or 3) Neotame daily during three, two-week intervention periods with a two-week washout. The primary outcome was composite appetite score defined as [desire to eat + hunger + (100 - fullness) + prospective consumption]/4. FINDINGS: Each formulation elicited a similar reduction in appetite sensations (3-h postprandial net iAUC). Postprandial insulin (2-h iAUC) was lower after Neotame (95% CI (0.093, 0.166); p < 0.001; d = -0.71) and StRebM (95% CI (0.133, 0.205); p < 0.001; d = -1.01) compared to sucrose, and glucose was lower after StRebM (95% CI (0.023, 0.171); p < 0.05; d = -0.39) but not after Neotame (95% CI (-0.007, 0.145); p = 0.074; d = -0.25) compared to sucrose. There were no differences between S&SE or sucrose formulations on ghrelin, glucagon-like peptide 1 or pancreatic polypeptide iAUCs. No clinically meaningful differences between acute vs. two-weeks of daily consumption were found. INTERPRETATION: In conclusion, biscuits reformulated to replace sugar using StRebM or Neotame showed no differences in appetite or endocrine responses, acutely or after a two-week exposure, but can reduce postprandial insulin and glucose response in adults with overweight or obesity. FUNDING: The present study was funded by the Horizon 2020 program: Sweeteners and sweetness enhancers: Impact on health, obesity, safety and sustainability (acronym: SWEET, grant no: 774293).

Acute and repeated impact of sweeteners and sweetness enhancers in solid and semi-solid foods on appetite: protocol for a multicentre, cross-over, RCT in people with overweight/obesity - the SWEET Project.

INTRODUCTION: Intake of free sugars in European countries is high and attempts to reduce sugar intake have been mostly ineffective. Non-nutritive sweeteners and sweetness enhancers (S&SEs) can maintain sweet taste in the absence of energy, but little is known about the impact of acute and repeated consumption of S&SE in foods on appetite. This study aims to evaluate the effect of acute and repeated consumption of two individual S&SEs and two S&SE blends in semisolid and solid foods on appetite and related behavioural, metabolic and health outcomes. METHODS AND ANALYSIS: A work package of the SWEET Project; this study consists of five double-blind randomised cross-over trials which will be carried out at five sites across four European countries, aiming to have n=213. Five food matrices will be tested across three formulations (sucrose-sweetened control vs two reformulated products with S&SE blends and no added sugar). Participants (body mass index 25-35 kg/m2; aged 18-60 years) will consume each formulation for 14 days. The primary endpoint is composite appetite score (hunger, inverse of fullness, desire to eat and prospective food consumption) over a 3-hour postprandial incremental area under the curve during clinical investigation days on days 1 and 14. ETHICS AND DISSEMINATION: The trial has been approved by national ethical committees and will be conducted in accordance with the Declaration of Helsinki. Results will be published in international peer-reviewed open-access scientific journals. Research data from the trial will be deposited in an open-access online research data archive. TRIAL REGISTRATION NUMBER: NCT04633681.

Impact of Maltitol and Sorbitol on Technological and Sensory Attributes of Biscuits.

Overconsumption of sugars in diets is associated with many health problems, including dental diseases, diabetes and obesity. However, removing sugar from products such as biscuits is still a challenge for manufacturers and has been limited in Europe since the evolution of the EU regulation in January 2018, allowing only polyols and non-sweetening bulking agents as sugar substitutes. This study investigated the effects of fully replacing sugar with two polyols, maltitol and sorbitol, in short-dough biscuits. Morphological, textural and visual characteristics were studied as well as sensory properties. The reformulated biscuits were more compact in shape and structure. They were also less prone to checking, which was attributed to a more homogeneous water distribution at the end of baking, especially with sorbitol. Polyol biscuits were surprisingly colourful, especially sorbitol ones, although polyols are not normally involved in Maillard reactions. Sensory tests, however, showed a depreciation of the products compared to the control. Sorbitol biscuits were the least preferred but maltitol ones were quite well accepted compared to the control. Thus, maltitol is an excellent potential substitute for this type of product.

Aroma-retention capacities of functional whey protein aggregates: Study of a strawberry aroma in solutions and in fat-free yogurts.

The aroma-retention capacity of functional whey protein aggregates (WPA) was compared to that of native whey protein isolate (WPI) in aqueous solutions and in fat-free yogurts. The retention of aroma compounds, constituting a model strawberry aroma, was evaluated by calculating gas-matrix partition coefficients using headspace gas chromatography (HS-GC). The retention capacity of WPA differed from the one of WPI for three out of seven aroma compounds detected in HS-GC. Incorporating WPA in fat-free yogurts tended to decrease the release of hydrophobic aroma compounds such as 2-nonanone or methyl-cinnamate. The magnitude of the differences between the partition coefficients of yogurts enriched in WPI or WPA was lower than in aqueous solutions, which is likely to be due to the higher complexity of the food matrix and potential interactions with other ingredients. Overall, the different aroma-retention capacities of native WPI and functional WPA are likely to lead to unbalanced aroma, especially in fat-free dairy products.

Can instrumental characterization help predicting sour taste perception of wheat sourdough bread?

Sourdough bread is known to have a characteristic sour taste. To guarantee consumer acceptability, sour taste should be monitored to assure constant bread quality. However, little is known about bread sour taste perception, especially how it evolves during tasting, neither if some simple measurements could help predict it. The aims of this study were to characterize the evolution of sour taste perception during bread tasting and to determine which bread instrumental variables can be correlated to it. For that purpose, eight types of bread were made with different sourdoughs and baking processes to obtain wide ranges of acidity, density and Fermentation Quotient. Bread were characterized by instrumental methods (i.e. pH, Total Titratable Acidity, organic acid content and density measurements) and their sour taste was determined by Quantitative Descriptive Analysis and a dynamic method called Progressive Profiling. As a result, it appeared that breads were perceived as significantly different throughout tasting. The "sour taste profile" was globally similar among breads with the highest intensity reached at the swallowing point. Progressive Profiling seemed then an efficient and simple method to evaluate the intensity of food organoleptic properties as well as the persistence after swallowing. Surprisingly, bread acetic acid content and Fermentation Quotient showed no effect on sour taste perception. Conversely, from all the physicochemical characteristics monitored, bread pH correlated with sour taste the most, explaining up to 97% of sour taste variations. Measuring bread pH could therefore constitute a quick and easy way to predict bread sour taste perception in research and industry.

Use of random forest methodology to link aroma profiles to volatile compounds: Application to enzymatic hydrolysis of Atlantic salmon (Salmo salar) by-products combined with Maillard reactions.

To use salmon protein hydrolysates as food ingredients and to mask the fish odor, Maillard reactions were associated with enzymatic production of hydrolysates. The study explored an original approach based on regression trees (RT) and random forest (RF) methodologies to predict hydrolysate odor profiles from volatile compounds. An experimental design with four factors: enzyme/substrate ratio, quantity of xylose, hydrolysis and cooking times was used to create a range of enzymatic hydrolysates. Twenty samples were submitted to a trained panel for sensory descriptions of odor. Hydrolysate volatile compounds were extracted by means of Headspace Solid Phase MicroExtraction (HS-SPME) and analyzed using gas chromatography/mass spectrometry (GC-MS). The results showed that RT and RF methodologies can be useful tools for predicting an entire sensory profile from volatile compounds. Four main volatile compounds made it possible to separate hydrolysates into five groups according to their specific sensory profile. 2,5-dimethylpyrazine, 1-hydroxy-2-propanone and 3-hydroxy-2-pentanone were identified as the main predictors of the roasted odor, whereas methanethiol was associated with a mud odor. These results also suggest the appropriate process conditions for obtaining a typical roasted odor.

Effect of Salt Reduction on Children's Acceptance of Bread.

Salt reduction is becoming a major concern for public authorities, especially in cereal products. As childhood is important for the development of healthy eating habits, this study aimed to formulate salt-reduced breads with satisfying sensory properties for children. Sourdough and an artisanal bread-making process were used to compensate the flavor loss due to salt reduction. French breads (FBs) made with sourdough and artisanal processing were compared with white breads (WBs). Two salt levels were applied (1.2 and 1.8 g /100 g flour). To determine their acceptability and characterization, the four breads were assessed (i) by an adult panel (n = 39) according to cohesiveness, overall odor intensity, overall aroma in the mouth and saltiness intensity and (ii) a panel of children (n = 100, aged 6 to 11 years) according to overall liking and saltiness intensity. Finally, consumption by children (n = 89, aged 6 to 11 years) was measured during school lunch to evaluate the acceptability of salt reduction in a real consumption context. Both formulation and salt level induced physical and sensory changes in breads perceived by adults. They described WB as less dense, cohesive, and aromatic but more odorant than FB. Saltiness differences were perceived by adults but not by children. Children showed a preference for the saltiest breads and the FB but these drivers of preference were not confirmed during consumption measurements. These results shed new light on how natural solutions to enhance the flavor of bread can reduce its salt level while maintaining acceptability. PRACTICAL APPLICATION: Salt reduction in bread could be compensated by the use of sourdough and an artisanal bread-making process. These methods allow an improvement of the nutritional quality of breads while maintaining their acceptance by young consumers by favoring the development of appealing organoleptic characteristics (aroma, texture). These methods are natural, easy to implement, and could be adapted to other fermented products in order to improve their nutritional quality.

Characterization of aroma-active compounds in rainbow trout (Oncorhynchus mykiss) eliciting an off-odor.

The aroma-active and off-flavor compounds of cooked rainbow trout (Oncorhynchus mykiss) were analyzed by sensory and instrumental analyses. Sensory analysis shows that the aromatic extract obtained by vacuum steam distillation was representative of rainbow trout odor. To obtain more information on odorants of volatile compounds, analyses were conducted on two gas chromatography columns of different polarities (DB-5 and DB-Wax). The results of the gas chromatography-olfactometry analysis showed that 38 odorous compounds were perceived when the DB-5 column was used and 36 with the DB-Wax column. Of these, 31 with the DB-5 and 28 with the DB-Wax were identified. (E)-2-Nonenal, 2-ethyl-1-hexanol, 2-methylisoborneol, geosmin, 2-methylnaphthalene, and 8-heptadecene were described as off-flavor compounds by the sniffing assessors. The most powerful off-flavor compounds identified in the extract were 2-methylisoborneol and geosmin, which were described as strong musty and earthy odors, respectively.

Mitigation strategies of acrylamide, furans, heterocyclic amines and browning during the Maillard reaction in foods.

The Maillard reaction (MR) occurs widely during food manufacture and storage, through controlled or uncontrolled pathways. Its consequences are ambiguous depending on the nature and processing of the food products. The MR is often used by food manufacturer to develop appealing aromas, colour or texture in food products (cereal based food, coffee, meat…). However, despite some positive aspects, the MR could decrease the nutritional value of food, generate potentially harmful compounds (e.g. acrylamide, furans, heterocyclic amines) or modify aroma or colour although it is not desired (milk, fruit juice). This paper presents a review of the different solutions available to control or moderate the MR in various food products from preventive to removal methods. A brief reminder of the role and influence of the MR on food quality and safety is also provided.

Odour quality of spray-dried hens' egg powders: the influence of composition, processing and storage conditions.

This study aimed to determine whether compositional or processing parameters have an influence on the odour quality of egg powders. The parameters tested were: whole egg vs. egg yolk, polyunsaturated fatty acid (PUFA) enrichment, spray-drying temperature (160°C vs. 180°C), production scale (industrial vs. pilot plant), storage temperature (15°C vs. 30°C) and time (1, 2, 4 and 8 months). The quality of egg powders was evaluated by sensory analysis using free sorting, and by gas chromatography coupled to mass spectrometry and olfactometry. PUFA enrichment and spray-drying temperature do not affect the odour of egg yolk powders. There are significant differences between the odour of whole-egg and egg-yolk powders as well as between powders produced on an industrial scale or in a pilot plant. An increase in the odour intensity of egg powders was observed during storage, while unpleasant odours were perceived when the egg powders were stored at 30°C.