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The increasing need for sustainable food choices places a demand on developing palatable foods from lower impact production and with a suitable shelf-life. In this context, knowledge of the sensory properties of whole sterilised chickpeas is required to be able to make them more attractive to the consumers. The sensory quality of chickpeas is largely dependent on the aroma and flavour, which can be influenced by storage conditions. In this study, sterilised chickpeas in two different packaging materials with different oxygen permeabilities, stored up to 52 weeks at ambient temperature (20 °C) were investigated using both descriptive sensory profiling and gas chromatography – mass spectrometry – olfactometry analysis (GC-MS-O). During storage, intense, sulphury and meat-like aromas decreased in intensity, while with longer storage time hay-like, green-like and potato-like flavours and aromas became more apparent. A total of 40 odour-active volatiles were detected, of which some had properties reminiscent of the chickpea flavour profiles. However, no clear relationships could be established between these odorants and the sensory changes observed during storage by descriptive sensory analysis. It was concluded that, significant changes in the sensory attributes of sterilised chickpeas occurred during 52 weeks of storage, but that packaging material does not seem to largely influence the sensory attributes during storage., Graphical abstract Image 1, Highlights • Significant sensory changes occur in sterilised chickpeas during 52 weeks storage. • 40 odour-active volatiles are detected in the sterilised chickpeas. • Sulphur compounds formed during sterilisation change during storage. • Hay and green attributes are perceived more intense with increased storage time. • Oxygen permeability of packaging does not impact the sensory quality during storage.

Effect of depuration on content of geosmin in pikeperch (Sander lucioperca) produced in a commercial RAS farm was examined during a 15-day period. Concentrations of geosmin in the fish were related to geosmin content in the water. For depuration, half of the water volume in a 230 m3 production tank was replaced daily with geosmin-free water. After 8 days of depuration and absence of feeding, content of geosmin in the fish was reduced from 710 ± 245 ng/kg to 165 ± 50 ng/kg (mean ± SD, p < .01). Additional depuration for 7 days only reduced the geosmin content to 135 ± 24 ng/kg. Geosmin concentration in the water was initially 34 ng/L but declined to 10 ng/L after 15 days. Changes in geosmin concentrations in water of the depuration tank indicated that geosmin was released by the fish during the depuration. In addition to removal of geosmin, the depuration also decreased concentrations of 28 different volatile compounds from the fish. Sensory analysis showed decrease in intensity of geosmin flavor upon depuration and improved the overall sensory quality of the fish after 2 weeks of depuration. Our study shows that geosmin and other off-flavors in pikeperch from RAS production can efficiently be removed to be a level that is below the threshold to most consumers.

Ultra-high temperature (UHT) processed lactose-reduced milk containing added green tea extract (GTE) at two concentrations (0.1% and 0.25%) was stored at 22 ± 2 °C for one year. The effect of GTE addition on physical stability, protein binding, and sensory quality was evaluated. Sedimentation in skim milk and creaming of full fat milk were inhibited by addition of GTE. The formation of Maillard-related flavour compounds was inhibited during storage as determined by dynamic headspace GC–MS. Using Western blot analysis, milk proteins were found to be highly conjugated to polyphenols. Addition of GTE before UHT treatment resulted in increased bitterness and astringency in UHT milk and this remained during storage. Even though GTE addition improved the physical stability and inhibited Maillard reactions in the milk, the taste and flavour contribution from GTE was dominating throughout storage, and alternative sources of polyphenols should be explored for increasing shelf-life stability of long-life milk.

The objective of this study was to investigate the impact of endo- and exo-peptidase treatment on certain structural characteristics of peptides and volatile compounds of porcine hemoglobin and whole blood hydrolysates. Porcine hemoglobin and whole blood were hydrolyzed by endo- and exo-peptidases. The presence of exopeptidases reduced the bitterness and altered the volatile profiles of protein hydrolysates. Exopeptidase treatment can release terminal amino acids from peptides, which in turn may contribute to formation of volatile compounds by Maillard reactions. In contrast, endopeptidases conferred a slightly bitter taste and different volatile profiles. For hemoglobin hydrolysates, principal component analysis revealed that proteases were categorized into three groups based on endo- or exo-peptidase activity. Whole blood is a more complex raw material, yet the proteases were still categorized in a similar fashion. This work contributes to understanding structural characteristics responsible for taste and volatile profiles of protein hydrolysates.

High lipid and high protein infant formula milk powders were stored at water activity of 0.11, 0.33 and 0.53 for up to fourteen weeks at 40 °C to investigate the effect of storage water activity on physicochemical properties and formation of volatiles to thereby recommend optimal storage water activity conditions. Water activity of the powders was determined during storage together with surface colour, glass transition temperature combined with dynamic headspace sampling followed by gas chromatography/mass spectrometry. The principal component analysis (PCA) showed that the optimal water activity for storage of high lipid infant formula milk powder, for which lipid oxidation was found to be the critical quality parameter, is aw = 0.33 with lowest lipid oxidation, while for high protein infant formula milk powder, for which protein degradation was found to be the critical quality parameter, aw = 0.11 is optimal to limit formation of Maillard reaction products.

The specialty coffee industry is growing and, as a result, there is an accelerated interest in modulating roast profiles to present customers with new and diverse sensory experiences. The present study investigates the chemical and sensory effects of subtle variations in the ‘development time’ phase of the coffee roasting process. Four roast profiles were studied through sensory descriptive analysis (DA), gas chromatography–mass spectrometry (GC–MS), and nuclear magnetic resonance (NMR). Multivariate analysis showed clear separation of DA, GC–MS, and NMR data. A prolonged development time facilitated a statistically significant shift in the chemical and sensory profile of the coffee. The findings suggest that a short development time increases the fruity, sweet and acidic characteristics of the coffee, whereas a longer development time shifts the balance towards a more roasty, nutty, and bitter profile. The results provide evidence that supports the effect of subtle roast profile modulations. This lays a strong foundation for the inclusion of development time as a critical control parameter in the certification system of the Specialty Coffee Association, quality control, and product development strategies.

Protein degradation, rheological properties, sensory properties and the aroma profile of soft brined cheese made from camel milk using two levels of coagulant (camel chymosin) [55 and 85 International Milk Clotting Units (IMCU) L−1] and two levels of brine (2% or 5% NaCl, w/w) were investigated over a ripening period of 60 d. Casein degradation in soft brined camel milk cheese significantly (p

Introduction: Umami is a basic taste. However, practitioners often refer to it as a flavour, indicating that sensory interactions may affect the gustatory response. Dashi is a basic soup stock that can be made simply by extracting seaweed into water (Mouritsen, Williams, Bjerregaard, & Duelund, 2012). By creating a sensory diverse set of dashis, we can explore odour-induced umami enhancement by omitting the sense of smell in sensory characterization of the dashis. Methods: Dashis were made from 16 seaweeds (9 different species) collected from locations in 6 different countries, following procedures of Mouritsen et al. (2012). Samples were characterised by standard sensory descriptive analysis (with and without olfactory input), HPLC (Mouritsen, Duelund, Calleja, & Frøst, 2017) and GC (Juhari & Petersen, 2018). Results: Main effects of olfactory stimulation was found for the basic tastes umami (p=0.001), sweet (p=0.017), and the flavour roasted (p=0.01), with decreases in intensity when olfactory input is prevented. Similar effects were found for the aftertastes astringent, metallic and fatty. However, odour-induced enhancement, indicated by statistical interactions between olfactory input and samples was only seen for umami (p=0.018) and astringent (p=0.009). HPLC analysis demonstrated that three samples (table 1) with high umami intensity had very low glutamate content. Scrutinizing the aroma compound concentration by GC identifies a set of candidates that can have increased umami (table 1). Conclusions: Sensory interactions between basic tastes and aroma compounds were found in seaweed dashi. Odours that enhance umami were observed in three samples with very low glutamate content. A number of potential odour-induced umami enhancing aroma compounds is suggested (table 1). Odour-induced umami enhancement can be used to create more palatable foods with simple and sustainable means.

This study explored the amino acid utilisation by Debaryomyces hansenii and Yamadazyma triangularis grown on cheese agar at 16 °C and 25 °C. The consumption of amino acids was species- and strain-dependent and greatly affected by temperature. For D. hansenii, the consumption of most amino acids was higher at 25 °C compared with 16 °C, contrary to Y. triangularis. Debaryomyces hansenii produced more 2- and 3-methyl-butanal, 3-methyl-1-butanol, and 2-phenylethanol, and consumed more of the corresponding amino acids, isoleucine, leucine, and phenylalanine, respectively, than Y. triangularis at 25 °C. Yamadazyma triangularis produced more volatile sulphur compounds, and consumed more of their precursor, methionine, than D. hansenii at 16 °C. Moreover, Y. triangularis seemed able to markedly consume the volatile sulphur compounds at 25 °C. These results may contribute to the selection of appropriate yeasts to be used in the cheese industry.

The effect of epigallocatechin gallate enriched green tea extract (GTE) on flavor, Maillard reactions and protein modifications in lactose-hydrolyzed (LH) ultrahigh temperature (UHT) processed milk was examined during storage at 40 °C for up to 42 days. Addition of GTE inhibited the formation of Strecker aldehydes by up to 95% compared to control milk, and the effect was similar when GTE was added either before or after UHT treatment. Release of free amino acids, caused by proteolysis, during storage was also decreased in GTE-added milk either before or after UHT treatment compared to control milk. Binding of polyphenols to milk proteins was observed in both fresh and stored milk samples. The inhibition of Strecker aldehyde formation by GTE may be explained by two different mechanisms; inhibition of proteolysis during storage by GTE or binding of amino acids and proteins to the GTE polyphenols.

Wine is often used as an ingredient in butter sauces such as hollandaise sauce, but normally in its reduced form. Hollandaise sauce is an emulsion, and roughly consists of a continuous phase (water based ingredients) and a dispersed phase (fat). In addition, hollandaise sauce contains varying amounts of incorporated air, seen as air bubbles in the sauce. In this study, the influence of wines and wine reductions on sauce flavor was studied. Butter sauces, where the aqueous phase of the sauces varied, were made and analyzed. Four different types of white wine (Chardonnay, Riesling, Sauvignon blanc and a blended wine) and these wines’ corresponding wine reductions were incorporated in butter sauce to produce model products (eight sauces in total). In the reductions, approximately 51% of the volume was removed by evaporation. The wines were selected based on both non-volatile composition and aroma differences. A trained sensory panel (n=10) evaluated sauce flavor and texture. Volatile profiles of sauces were studied by GC-MS, and sauce texture was evaluated by texture analysis, microscopy and dry matter measurements. Results showed that the degree of reduction is more important for sauce flavor than the wine type.

Different types of cheese powder were added to meat emulsion sausages in order to address its influence on chemical composition, volatile compounds profile and sensory properties, and its potential to reduce salt content through boosting saltiness. Addition of cheese powder to emulsion sausages modified their profile of volatile compounds. Blue cheese increased some ketones, alcohols, and esters, while brown cheese brought typical Maillard reaction compounds. Overall, addition of cheese powders to sausages enhanced the intensity of flavour traits. A mixture of hard and blue cheese powder showed the highest effect on boosting saltiness, while brown cheese powder showed the strongest umami and meat flavour boosting effect, and sausages with added blue cheese powder showed a more intense aftertaste. Hardness significantly increased due to the addition of blue cheese powder. Addition of cheese powder to emulsion sausages might be an interesting tool to boost flavour and reduce salt content in cooked sausages with no negative effect on saltiness or overall flavour.

The present study aimed to investigate coffee flavour perception and release as function of serving temperature to support standardisation in the specialty coffee branch. The coffee cultivar Bourbon Caturra was evaluated at six serving temperatures ranging from 31°C to 62°C. Coffee samples were analysed by dynamic headspace sampling gas chromatography-mass spectrometry and descriptive analyses using sip-and-spit tasting. The release of volatiles followed mostly the van't Hoff principle and was exuberated at temperatures above 40°C. Aliphatic ketones, alkylpyrazines, some furans and pyridines increased most notably at temperatures ⩾50°C. The changes in volatile release profiles could explain some of the sensory differences observed. The flavour notes of 'sour', 'tobacco' and 'sweet' were mostly associated with the coffees served at 31-44°C, whereas coffees served between 50°C and 62°C exhibited stronger 'overall intensity', 'roasted' flavour and 'bitter' notes.

In this study, we compare the effects of single- and double-cycle HP treatments at 600 MPa on inactivation of the natural microflora and physicochemical properties of whole and skimmed milk of high bacterial load. The results show that two-cycled HP (2 × 2.5 min) was more effective (P 0.05) in physicochemical properties of milk in comparison to single cycled HP (1 × 5 min). In addition to the expected milk protein structure changes, HP at 600 MPa caused only slight effects on milk fat and lactose. Minor decreases in levels of short chain fatty acids were observed with the cycled treatments, and the volatiles in general decreased after HP treatment, depending mostly on the pressure time but also on cycling in skimmed milk. The study confirmed the superior effect of two-cycle HP on microbial inactivation, and shows a slightly better preservation of the physical-chemical milk quality. Industrial relevance Multi-cycling HP has been shown to be advantageous for microbial inactivation, but limited information is available regarding the effect on milk components in whole milk or skimmed milk. The present study compares the psychochemical properties of whole and skimmed milk processed by multi-cycling in comparison to single cycle HP treatment. Double cycled HP presented a superior effect on microbial inactivation and slightly better preservation of milk quality than one continuous HP.

Ethanol concentration in batters prepared with alcoholic beverages was measured upon deep frying, using static headspace GC-MS. The concentration decreased dramatically during the first two minutes of frying resulting in a concentration of maximum 0.28 ± 0.03 g/100 g. Frying for another two minutes had an insignificant effect on the concentrations. The measured concentrations resulted in 0.14 g ethanol per serving, which is considered very low and not problematic for human consumption. When the batter was fried as a coating for fish, the concentrations were slightly higher than when fried alone, namely 0.69 ± 0.21 g/100 g after two minutes of frying.

In recent decades, intensive selective breeding programs have allowed the development of disease-resistant and flavorsome apple cultivars while leading to a gradual decline of a large number of ancient varieties in many countries. However, the re-evaluation of such cultivars could lead to the production new apple-based products with health beneficial properties and/or unique flavor qualities. Herein, we report the comprehensive characterization of juices obtained from 86 old, mostly Danish, apple cultivars, by employing traditional analysis (ion chromatography,◦Brix, headspace gas chromatography/mass spectrometry (GC–MS), and panel test evaluation) as well as an innovative nuclear magnetic resonance (NMR)-based screening method developed by Bruker for fruit juices, known as Spin Generated Fingerprint (SGF) Profiling™. Principal component analysis showed large differences in aroma components and sensory characteristics, including odd peculiar odors and flavors such as apricot and peach, and very different levels of phenolic compounds, acids and sugars among the analyzed juices. Moreover, we observed a tendency for late-season juices to be characterized by higher◦Brix values, sugar content and they were perceived to be sweeter and more flavor intense than early-season juices. Our findings are useful for the production of specialty vintage-cultivar apple juices or mixed juices to obtain final products that are characterized both by healthy properties and peculiar sensory attributes.

There has been an increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. In this work, three non-Saccharomyces yeast strains (Metschnikowia viticola, Metschnikowia fructicola and Hanseniaspora uvarum) indigenously isolated in Denmark were used in sequential fermentations with S. cerevisiae on three cool-climate grape cultivars, Bolero, Rondo and Regent. During the fermentations, the yeast growth was determined as well as key oenological parameters, volatile compounds and sensory properties of finished rose wines.; Results: The different non-Saccharomyces strains and cool-climate grape cultivars produced wines with a distinctive aromatic profile. A total of 67 volatile compounds were identified, including 43 esters, 14 alcohols, five acids, two ketones, a C13-norisoprenoid, a lactone and a sulfur compound. The use of M. viticola in sequential fermentation with S. cerevisiae resulted in richer berry and fruity flavours in wines. The sensory plot showed a more clear separation among wine samples by grape cultivars compared with yeast strains.; Conclusion: Knowledge on the influence of indigenous non-Saccharomyces strains and grape cultivars on the flavour generation contributed to producing diverse wines in cool-climate wine regions. © 2017 Society of Chemical Industry.; © 2017 Society of Chemical Industry.

The influence of fermentation temperatures (8°C, 16°C, and 32°C) and yeast levels (2%, 4%, and 6% of the flour) on the formation of volatile compounds in the crust of whole meal wheat bread was investigated. The fermentation times were regulated to optimum bread height for each treatment. The volatile compounds were extracted by dynamic headspace extraction and analyzed by gas chromatography-mass spectrometry. The results were evaluated using multivariate data analysis and ANOVA. In all crust samples 28 volatile compounds out of 58 compounds were identified and the other 30 compounds were tentatively identified. Higher fermentation temperatures promoted the formation of Maillard reaction products 3-methyl-1-butanol, pyrazine, 2-ethylpyrazine, 2-ethyl-3-methylpyrazine, 2-vinylpyrazine, 3-hydroxy-2-butanone, 3-(methylsulfanyl)-propanal, and 5-methyl-2-furancarboxaldehyde whereas at lower temperature (8°C) the formation of 2- and 3-methylbutanal was favored. Higher levels of yeast promoted the formation of 3-methyl-1-butanol, 2-methyl-1-propanol and 3-(methylsulfanyl)-propanal, whereas hexanal was promoted in the crust fermented with lower yeast level.

Nowadays, the use of non-Saccharomyces yeasts in combination with Saccharomyces cerevisiae is being recognised to enhance the analytical composition of the wines. The aim of this work was to evaluate the influence of indigenous non-Saccharomyces yeasts on the flavour character of wines from the cool-climate grape cultivar Solaris in Denmark. The volatile and non-volatile compounds as well as the sensory properties of wines were evaluated. Solaris wines with Hanseniaspora uvarum sequentially inoculated with S. cerevisiae produced a larger amount of glycerol as well as heptyl acetate and 2-phenylethyl acetate. This co-culture fermentation also produced higher amounts of ethyl acetate and acetic acid, reducing the possibility of its use in winemaking. Three Metschnikowia strains, a M. chrysoperlae strain and two M. fructicola strains, gave a comparable production of volatile compounds. These wines were characterised by several floral and fruity attributes. The Metschnikowia strains turned out to be promising in winemaking from Solaris grapes.

Caraway (Carum carvi) is used as a vegetable; more commonly, the fruits are used to flavour foods or as a preservative. Quality is a key issue; however, little is known about the respective influences of type of material and location and the interaction of these factors on essential oil composition. In this study, wild populations and commercial cultivars from the Nordic germplasm collection were examined. Plants were grown in two locations (Iceland and Sweden) and essential oil composition and phenotypic characteristics identified. Carvone and limonene were the two major compounds detected at levels around 14 and 70% of total peak area, respectively. Also p-cymene, trans-β-ocimene, α-Terpinolene and myrcene each were detected at levels above or around 2%. In total, 47 compounds were detected of which 40 were identified. The effects of material type and location were established, where location had a greater impact than genotype. In 15 out of the 35 compounds detected at levels below 2%, significant location-dependent differences were detected. For morphological traits, genotype had a more significant effect than location.

The influence of fermentation temperatures (8, 16, and 32°C) and yeast levels (2, 4, and 6%) on the formation of volatile compounds in the crumb of whole-meal wheat bread was investigated. Volatile compounds were extracted by dynamic headspace extraction and analyzed by gas chromatography–mass spectrometry. Results were evaluated with multivariate data analysis and ANOVA. Bread fermented at a high temperature (32°C) had higher peak areas of the Maillard reaction products 2-furancarboxaldehyde, 2-acetylfuran, 2-methylpyrazine, and phenylacetaldehyde compared with bread fermented at lower fermentation temperatures. Bread fermented at low temperatures (8 and 16°C) was characterized by having higher peak areas of the fermentation products 3-methylbutanal, 2-methylbutanal, ethyl acetate, ethyl hexanoate, ethyl propanoate, and 3-methylbutanol. Fermentation of bread with 6% yeast resulted in a higher peak area of the important fermentation product 2-phenylethanol. It also reduced the peak areas of important lipi...

Quality of whole milk pasteurized by high hydrostatic pressure processing (HPP: 600 MPa for 5 min) or HPP combined with microfiltration (MF + HPP) were compared with two conventional heat treatments, low temperature long time (LTLT: 63 °C for 30 min) and high temperature short time (HTST: 72 °C for 15 s). Inactivation of microorganisms, changes in volatiles, protein denaturation, gastric digestion, and sensory quality were evaluated after 8 days of storage at 5 °C. Total bacterial and E.coli counts were reduced to approximately the same level for both high pressure and heat treated milks. The denaturation of β-lactoglobulin was significantly higher for high-pressurized milks, while no significant differences were found in gastric in-vitro protein digestion compared with heat treated milks. The results of volatile compounds revealed that HTST and HPP-treated milks exhibited very similar aroma profiles, while LTLT-milks were characterized by higher levels of ketones. After 8 days storage, the sensory analysis showed that LTLT milk was the one that differed most from the other three milks with highest intensities of all the sensory attributes, while no tangible differences were found between HTST and any HPP and MF + HPP milk, except for Boiled Taste that was slightly but significantly lower for MF + HPP.

Whey protein isolate (WPI) is widely used as a protein ingredient in foods, but undergoes thermal treatment before and during application to make the final product. The aim of the present study was to determine the temperature dependency of formation of volatiles that potentially act as off-flavours in reconstituted WPI solutions (3%, w/v) heated for different temperature–time combinations (50–90 °C for 5–10 min). Differences in orthonasal aroma were evaluated by triangle tests by a sensory panel. The panel could distinguish between samples heated for 10 min at 60 °C and 70 °C. Analysis by headspace gas chromatography-mass spectrometry (GC-MS) showed that heating the samples at 90 °C for 10 min significantly increased the concentration of dimethyl disulphide and dimethyl trisulphide compared with heating at 80 °C for 10 min or below, which suggests that sulphur-derived odour could be decreased by decreasing the heating temperature by 10 °C.

1. Two experiments were carried out in parallel with male Ross 308 broilers over 37 d. An experiment with a total of 736 broilers was performed to study the effect of dietary inclusion of crimped kernel maize silage (CKMS) on broiler production and meat quality. Another study with 32 broilers was carried out from 21-25 d to investigate the inclusion of CKMS on nutrient digestibility.2. In both trials, 4 dietary treatments were used: wheat based feed (WBF), maize based feed (MBF), maize based feed supplemented with 15% CKMS (CKMS-15) and maize based feed supplemented with 30% CKMS (CKMS-30).3. Compared with MBF, the DM intakes of broilers receiving CKMS-15 and CKMS-30 respectively were numerically 7.5 and 6.2 % higher, and FCR were 6 and 12 % poorer (significant for CKMS 30%), although there were no significant differences in AME content between the three diets. At 37 d, the body weight of birds receiving 15% CKMS was similar to birds fed with MBF. However, the inclusion of 30% CKMS decreased broiler growth. Dietary supplementation with CKMS significantly reduced the apparent digestibility of phosphorus. The fat digestibility was significantly lower for CKMS-30 than for the other 3 diets.4. Broiler mortality decreased significantly when CKMS was added to the diet.5. The consumption of drinking water was significantly lower in all maize based diets as compared to WBF and was lowest in broilers fed CKMS-30.6. An improved litter quality in terms of dry matter content and a lower frequency of foot pad lesions was observed with broilers supplemented with both dietary levels of CKMS.7. The addition of CKMS to maize based diets increased juiciness, tenderness and crumbliness of the meat.8. In conclusion, the dietary supplementation of 15% CKMS had no negative effect on broiler growth and positively influenced bird welfare in terms of mortality and foot pad health. Therefore, the addition of 15% CKMS to maize based diets is considered an advantageous feeding strategy in broiler production

There is a growing market for the use of hydrolysates from animal side-streams for production of high-protein supplements. However, there can be issues with development of off-flavors, either due to the raw material in question or due to the hydrolysis process itself. This study examined the development of volatile compounds during hydrolysis of hemoglobin. Briefly, porcine hemoglobin was hydrolyzed by 0.5% papain for up to 5 h, and the development of volatile compounds was analyzed via gas chromatography-mass spectrometry. The results showed that there was significant development of a number of volatile compounds with time, e.g., certain Maillard reaction and lipid oxidation products, which are likely candidates for the aroma development during hydrolysis. Furthermore, it was shown that development of a number of the volatiles was due to the hydrolysis process, as these compounds were not found in a control without enzyme.

Roselle (Hibiscus sabdariffa L.) is considered an underexploited food crop with nutritional and large scale processing potential. Roselle can be utilized as a functional food, mainly due to being rich in vitamin C, anthocyanins, other phytochemicals, and natural color. Although Roselle has been widely planted and consumed, little is known about the composition of aroma profiles. In this study, seventeen samples of dried Roselle calyx were collected from eight countries and the aroma profiles were determined by dynamic headspace sampling and GC-MS and GC-olfactometry. Furthermore, total soluble solids, pH, and color L* a* b* were determined, and sugars and acids were measured using ion chromatography. There were significant (p 0.05) differences in all measured variables in physicochemical properties and non-volatile compounds. A total of 135 volatiles were identified mainly terpenes, aldehydes, esters, furans, and ketones. Thirty-seven odorants were reported as potentially important aroma compounds based on GC-olfactometry. This study provides valuable information for future commercial utilization of Roselle in the food industry.

Milled Roselle (Hibiscus sabdariffa L.) seeds of the UMKL cultivar were analyzed for proximate composition, water and oil absorption capacity, and the influence of storage conditions on storage stability. The storage stability was determined under four types of conditions: light/oxygen (air) (LO), light/nitrogen (LN), darkness/oxygen (air) (DO), and darkness/nitrogen (DN) while monitoring for seven consecutive months. During the storage period, the formation of volatiles was determined using dynamic headspace sampling and Gas Chromatography-Mass Spectrometry (GC-MS) analysis. In total, 85 volatiles were identified, mainly aldehydes, alcohols, ketones, furans, and acids indicating lipid oxidation. It is recommended that milled Roselle seeds should be flushed with nitrogen and stored in darkness. Under these conditions, the seeds can be stored for at least three months without changes in volatile profile. This is important to ensure the good quality of milled Roselle seeds for further commercialization.

The aim of this study was to characterize the flavor profiles of 14 commercial apple ciders from the United Kingdom and Scandinavian region. The flavor properties were established by sensory profiling and analysis of volatile and non-volatile components, including titratable acidity, pH, residual sugars and organic acids. A total of 72 volatile compounds were identified in the 14 apple ciders using dynamic headspace sampling (DHS) coupled to gas chromatography-mass spectrometry (GC/MS). The main volatile compounds found in apple ciders were esters and higher alcohols, followed by aldehydes and fatty acids. Sensory characterizations of the aroma and taste of apple ciders were carried out by a trained sensory panel using descriptive analysis with 23 sensory attributes. The attributes apple, cooked apple, yeasty, sweet and sour were the most predominant sensory descriptors used to describe the similarities and differences in the samples. Principal component analysis (PCA) showed that floral and fruity (fresh apple, banana and pear) odors were highly associated with sweet taste and opposed to the more complex aroma attributes (yeasty, lactic, chemical, mouldy, black pepper and earthy) and sour taste. Most of the UK apple ciders were characterized by these complex odors and taste notes sour, astringent and bitter, whereas ciders from the Scandinavian region had diverse sensory profiles. Partial least squares regression (PLS) based on the sensory and chemical data was able to cluster the ciders according to differences in production methods (oak-aged or spontaneous fermentation; controlled malolactic fermentation; industrial production with flavor modifications). Moreover, this study also suggested that ciders with marked levels of acetate esters were characterized by cooked/fresh apple, citrus and tropical fruit odors.

Geosmin and 2-methylisoborneol are the most recognized off-flavors in freshwater fish, but terpenes may also contribute off-flavor in fish. We identified six monoterpenes, 11 sesquiterpenes, and three terpene-related compounds in pangasius and tilapia from aquaculture farms in Bangladesh. The concentrations of most of the volatiles were below published odor thresholds, except for α-pinene, limonene, β-caryophyllene, α-humulene, and β-ionone in tilapia, and limonene and β-ionone in pangasius. To identify sources of the terpenes, terpene profiles of fish feed and phytoplankton in the ponds were analyzed. In feed and mustard cake (feed ingredient), five monoterpenes and two sesquiterpenes were identified, and five of these compounds were also detected in the fish. In phytoplankton, 11 monoterpenes were found and three also occurred in the fish. The higher number of terpenes common to both fish and feed, than to fish and phytoplankton, suggests that feed was a more abundant source of odor-active terpenes in the fish than phytoplankton.

Effect of water treatment on concentrations of the off-flavor geosmin was examined in a RAS facility for commercial production of pikeperch (Stizostedion lucioperca). Short-term (minutes) and long-term (days) variations in concentrations of geosmin were measured in grow-out tanks, at inlet and outlet of biofilters and at the denitrification unit. Geosmin in water of the grow-out tanks ranged typically from

Hexanal formation and pentanal formation were found to be early signs of quality deterioration of both a high lipid infant formula milk powder and a high protein infant formula milk powder with similar lactose and water content; these aldehydes were sensitive predictors for shelf-life at ambient conditions using short term storage at temperatures up to 55 °C. Higher temperature loads such as 70 °C were found to induce rapid lactose crystallisation entailing a rising water activity, higher levels of free radicals, rapid browning and formation of Strecker aldehydes from protein degradation, of which all were found to be unsuitable for shelf-life prediction. Advanced glycation end products were not detected during storage at 25 °C for up to 18 weeks and the rate of oxygen consumption for the reconstituted milk drink was not affected by storage of the infant formulas at 25 °C; neither can be recommended for shelf-life prediction.

Summary This paper studied the fast sensory Rate-All-That-Apply (RATA) method as a contributor to existing quality control (QC) in chocolate production by comparing it with the outcome of dynamic headspace sampling combined with gas chromatography–mass spectrometry (DHS-GC-MS). Seven different chocolates were evaluated by a semi-trained panel using RATA. RATA showed potential as a sensory evaluation tool which could be part of QC programmes in chocolate production as RATA was efficient to perform and captured important sensory deviations, herein addition of excess lecithin and prolonged roasting. However, product deviations caused by long conching were only detected by DHS-GC-MS. A more extreme conching process must occur before it can be perceived by humans. RATA and DHS-GC-MS should be used as complementary methods in detecting future important issues in chocolate production. DHS-GC-MS detects product deviation from chemical perspectives while sensory evaluation gives information on quality parameters from a perceivable perspective influencing consumer satisfaction.

Many essential oils and their terpene constituents display antimicrobial properties, which may affect rumen metabolism and influence milk production parameters. Many of these compounds also have distinct flavors and aromas that may make their way into the milk, altering its sensory properties. Essential oils from caraway (Carum carvi) seeds and oregano (Origanum vulgare) plants were included in dairy cow diets to study the effects on terpene composition and sensory properties of the produced milk, as well as feed consumption, production levels of milk, and methane emissions. Two levels of essential oils, 0.2 and 1.0 g of oil/kg of dry matter, were added to the feed of lactating cows for 24 d. No effects on feed consumption, milk production, and methane emissions were observed. The amount and composition of volatile terpenes were altered in the produced milk based on the terpene content of the essential oils used, with the total amount of terpenes increasing when essential oils were added to the diet. Sensory properties of the produced milk were altered as well, and milk samples from animals receiving essential oil treatment were perceived as having a fresher aroma and lower stored aroma and flavor. The levels of essential oils used in this study mimic realistic levels of essential oils in herbs from feed, but were too low to affect milk production and methane emissions, and their inclusion in the animal diet did not adversely affect milk flavor.