Flavor profiling of apple ciders from the UK and Scandinavian region

Effect of mixed fermentation of compound grapes on organic acids and volatiles in mulberry wine

The main objective of this study was to investigate the effect of mixed fermentation of blended grapes on the organic acid and volatile content of mulberry fruit wines before and after fermentation. Rose-scented grapes and blackberry grapes were chosen to produce fruit wines through mixed fermentation with mulberries, respectively. HPLC was employed for the content of organic acids, whereas the concentrations of volatile compounds in the mulberry wines were determined using HS-SPME-GC-MS. The results showed that yeast fermentation could effectively reduce the content of malic acid and citric acid while generating rich aroma substances. During compound grape blend fermentation, the organic acid content decreases, and more volatile compounds are produced. Among them, mulberry rosé grapefruit wine exhibits a more complex array of volatile compounds, including phenylethanol, ethyl caprylate, and ethyl caprate, alongside recently discovered compounds like isobutanol, (+)-3-methyl-2-butanol, and α-pinitol. These compounds contribute to the enhanced flavor of mulberry wine.

The potential of red-fleshed apples for cider production

Cider quality is influenced by numerous factors relating to the apples used during production. While extensive research has been done to explore the phenolic content, sensory quality, and storage stability of various apple products, the domain of fermented apple products, such as ciders, remains underrepresented. Red-fleshed apples (RFAs) have naturally high concentrations of phenolic compounds, which indicate their potential in the production of novel cider products. However, a knowledge gap remains regarding the application of RFAs in cider production and how their physicochemical and sensory properties are changed during processing. This review is the first to comprehensively investigate whether and to what extent apple categories (dessert, cider, and RFAs) differ regarding their physicochemical and sensory properties from harvest throughout cider processing. Furthermore, it highlights the importance of a holistic understanding of apple characteristics, encompassing both traditional and RFA varieties in the context of cider production. The findings offer valuable insights for stakeholders aiming to enhance product quality, providing a foundation for future studies on optimizing processing methods for a diverse and appealing range of ciders.

Impact of Co-Inoculation Patterns of Wickerhamomyces anomalus and Saccharomyces cerevisiae on Cider Quality and Aromatic Profiles

Co-inoculation with Saccharomyces cerevisiae and non-Saccharomyces yeasts is an effective method to improve the flavor of cider. Wickerhamomyces anomalus, known for its high ester production capacity, was evaluated in combination with S. cerevisiae to identify optimal mixed yeast inoculants for improved sensory characteristics. Three W. anomalus strains and three inoculation ratio attributes (1:5, 1:1, and 5:1) were tested to assess their impact on the physicochemical indices and sensory attributes of cider. All the strains used as starters developed fermentation-producing ciders with alcoholic degrees between 6.22 and 6.36 (% v/v). Co-inoculation with W. anomalus resulted in significantly higher ester, volatile acid, and higher alcohol levels compared to those of S. cerevisiae monocultures, increasing the complexity of fruity and floral aromas. Furthermore, the proportion of W. anomalus strains in the inoculations was positively correlated with increased aromatic esters and higher alcohols. The Sc-Wa (1:5) cider showed the highest contents of ethyl ethanoate and 3-methylbutan-1-ol, contributing to a nail polish-like aroma. Sc-Wa (1:1) yielded a higher aromatic diversity than did Sc-Wa (5:1), suggesting that co-inoculation with a ratio of 1:1 may provide an effective fermentation strategy for cider aroma enhancement. These findings offer valuable insights into how non-Saccharomyces yeasts can be effectively applied in cider co-fermentation, providing a foundation for their future use in industrial applications.

Aroma Release and Consumer Perception During Cider Consumption

Flavor is an important property affecting consumer acceptance, yet little is known about the correlation between the sensory attributes, volatile compounds, and consumer preference during cider consumption. This study was the first to evaluate which sensory attributes of commercial apple ciders in China were preferred by Chinese consumers. Meanwhile, GC-MS and GC-IMS were conducted to characterize the aroma release both in orthonasal and retronasal olfactory perceptions. The sensory analyses exhibited that Chinese consumers preferred "sweet cider", and sensory attributes such as "a-tropical fruit", "f-fruity" and "t-sweet" were the most popular. A total of 63 volatile compounds were identified using GC-MS, while both the variety and concentrations of these compounds detected by GC-IMS were lower. Finally, partial least squares (PLS) analysis was used to establish two models based on sensory data, and orthonasal and retronasal volatile compounds. The two models had 32 and 29 compounds with variable importance in projection (VIP) values > 1, respectively. The results revealed that the compounds with high correlation with "t-sweet" and "f-fruity" were roughly the same in two PLS models, whereas the number of compounds contributing positively to "t-sour" and "f-fermented" changed significantly.

Impact of co-fermentation of Saccharomyces cerevisiae and Pichia kluyveri on the metabolic characteristics of the flavor compounds in mulberry wine

This study investigated the metabolic characteristics of mulberry wine produced by co-fermentation with Saccharomyces cerevisiae (SC) and two different Pichia kluyveri (PK). Although S. cerevisiae inhibited the growth of P. kluyveri during co-fermentation, P. kluyveri showed robust growth adaptability. Classical oenological parameters were not significantly altered by co-fermentation compared to pure-fermentation. The P. kluyveri significantly modulated amino acid metabolism pathways during co-fermentation, enhancing the biosynthesis of higher alcohol acetate compounds. Furthermore, co-fermentation strategy promoted the production of volatile flavor compounds, particularly esters and alcohols, which enriched the wine with distinct floral and fruity flavors. This study provides novel insights into the metabolic mechanisms of co-fermentation with SC and PK strains and highlights the potential of P. kluyveri as a co-fermentation agent for improving the aromatic complexity of fruit wines.

Aromatic and sensorial profiles of Guichang kiwi wine fermented by indigenous Saccharomyces cerevisiae strains

The indigenous Saccharomyces cerevisiae (S. cerevisiae) serves as an essential tool for enhancing the sensory and aromatic profiles of fruit wines from specific regions. This study aims to investigate the effects of inoculating indigenous S. cerevisiae strains Sc1, Sc2, and a commercial strain Sy on the physicochemical properties, organic acids, sensory properties, and volatile compounds of Guichang kiwi wines (Sc1 wine, Sc2 wine, Sy wine) compared to unfermented kiwi juice. Compared to Sy wine, the ethanol concentration in Sc1 and Sc2 wines significantly increased, while the total organic acids content decreased, and the sensory properties of alcohol, fruity, and typicality were notably enhanced. Sc1 wine demonstrated the least reduction in vitamin C (VC) concentration and the lowest total organic acids concentration. Additionally, Sc1 wine surpassed Sc2 wine in terms of scores for alcohol, mouth-feel, acidity, floral, fruity, and typicality. A total of 47 volatile compounds were identified in both the juice and wines using the two-dimensional gas chromatography-mass spectrometry (GC × GC-MS) technique. A strong correlation was observed between 16 odor-active compounds and six sensory attributes, while nine aroma-active compounds (VIP > 1) were identified as the crucial differential compounds responsible for the aromatic characteristics of the juice and wines. Fermentation with Sc1 led to increased production of alcohols, ethyl esters, phenylethyl alcohol, and isoamyl acetate, which significantly enhanced floral and fruity flavors. This study provides evidence that fermentation with the indigenous S. cerevisiae strain Sc1 contributes to improving sensory attributes and enhancing aroma quality in Guichang kiwi wine. PRACTICAL APPLICATION: As kiwi wine continues to gain widespread popularity among consumers, there is an increasing preference for the use of indigenous yeast strains in the fermentation process. This study demonstrates that, compared to the indigenous S. cerevisiae strain Sc2 and the commercial strain Sy, the indigenous sourced S. cerevisiae strain Sc1 produced fermented wine with the lowest total organic acids content. Furthermore, it exhibits a greater diversity and concentration of volatile compounds, along with a more pronounced floral and fruity aroma. These findings suggest its potential to enhance both the sensory attributes and aroma quality of Guichang kiwi wine.

Revealing differences in flavor compounds during plum wine fermentation using single and mixed yeast strains through metabolomic analysis

Mixed fermentation can enhance the flavor and aroma of fruit wine, but the mechanisms driving this enhancement remain unclear. This study used non-targeted metabolomics to analyze the effects of mixed versus single fermentation on plum wine flavor. The results showed that compared with single fermentation, mixed fermentation reduced ethanol content and the ability to consume reducing sugars. In single fermentation, volatile compounds increased over time, while in mixed fermentation, they first increased and then declined. Mixed fermentation notably increased esters and reduced higher alcohols, with key differentiators including phenethyl acetate, hexyl acetate, isoamyl acetate, ethyl acetate, isoamyl alcohol, phenethyl alcohol, ethyl caproate, and isobutanol. Furthermore, 40 differential non-volatile flavor compounds were identified, with amino acids emerging as the predominant differentiators. The annotation analysis of these compounds revealed 11 important metabolic pathways for proline, aspartate, glutamate, and β-alanine metabolism. These findings provide insight about producing plum wines with distinct flavor profiles.

Effect of bacterial diversity on the quality of fermented apple juice during natural fermentation of Hanfu apples

The fermented cloudy apple juice (FCAJ) bacterial phase was analyzed by 16S rRNA gene-based sequencing. During fermentation, the bacterial phase transition promoted quality changes, such as carbohydrate, organic acid, total phenol, taste and volatiles of FCAJ. Citrobacter and Lactobacillus were the dominant bacterial genera of Hanfu apple juice by natural fermentation, and lactic acid was the most abundant organic acid in FCAJ. Citrobacter showed a continuous increase trend along with fermentation time, while Lactobacillus showed a slight decrease during the later period of fermentation. The contents of total phenolic and flavonoid both showed a trend of rising first and then decreasing in FCAJ during fermentation. Alcohols and esters, the main aromatic volatiles in FCAJ, showed significant increases, especially for ethanol, 3-methyl-1-butanol and ethyl acetate. Citrobacter presented a higher correlation than Lactobacillus with some volatile flavor.

Effect of sequential fermentation with indigenous non-Saccharomyces cerevisiae combinations and Saccharomyces cerevisiae on the chemical composition and aroma compounds evolution of kiwifruit wine

To unlock the potential of indigenous non-Saccharomyces cerevisiae and develop novel starters to enhance the aromatic complexity of kiwifruit wine, Zygosaccharomyces rouxii, Pichia kudriavzevii and Meyerozyma guilliermondii were pairwise combined and then used in sequential fermentation with Saccharomyces cerevisiae. The impact of different starter cultures on the chemical composition and flavor profile of the kiwifruit wines was comprehensively analyzed, and the aroma evolution during alcoholic fermentation was investigated by examining the changes in key volatiles and their loss rates. Compared with Saccharomyces cerevisiae, mixed starter cultures not only improve antioxidant capacity but also increase esters and alcohols yields, presenting intense floral and fruity aromas with high sensory acceptability. The results indicated that sequential inoculation of non-Saccharomyces cerevisiae combination and Saccharomyces cerevisiae promoted the development of volatiles while maintaining the stability of key aroma compounds in the winemaking environment and reducing the aroma loss rates during alcoholic fermentation.

Nutritional, Bioactive, and Volatile Characteristics of Two Types of Sorbus domestica Undervalued Fruit from Northeast of Iberian Peninsula, Spain

The promotion of food from underutilized plants can help combat biodiversity loss, foster cultural preservation, and empower farmers in the face of market pressures and sustainable production conditions. The nutritional and aromatic characterization of two undervalued types of Sorbus domestica fruits, differentiated by their apple and pear shapes, has been carried out. Official Association of Analytical Communities methods have been used for proximate composition and mineral analysis determinations, and gas chromatography was used for the analysis of volatile components in three states of ripeness and compared with the aromas of fresh apple and quince jam. S. domestica fruits are a good source of K, Ca, Fe, and fiber and are an important source of antioxidants in the human diet. S. domestica fruits have proven to be very distinctive in the aromatic fraction. 1-hexanol, hexyl 1,3-octanediol, phenylacetaldehyde, nonanal, hexanal, and α-farnesene are the most potent odor compounds in the overripening stage of the fruits. The aroma profiles of immature S. domestica fruits were dominated by aldehydes, while in the overripe stage, the fruit accumulated abundant esters, alcohols, and sesquiterpenoids. S. domestica fruits could be introduced as an alternative to seasonal fruit consumption and could generate sustainable production and consumption alternatives while recovering cultural and food heritage.

Effects of Torulaspora delbrueckii and Saccharomyces cerevisiae Co-Fermentation on the Physicochemical and Flavor Compounds of Huaniu Apple Cider

The effects of different fermentation methods utilizing Torulaspora delbrueckii 1004 and Saccharomyces cerevisiae 32169 on the physicochemical properties, organic acid content, polyphenol and flavonoid concentrations, antioxidant activity, and volatile aroma compounds of Huaniu apple cider were investigated in this study. Employing methods of single inoculation, co-inoculation, and sequential inoculation, it was found that sequential fermentation exhibited strong fermentative power in the initial stages, effectively reducing the content of soluble solids and achieving a balanced composition of malic, succinic, and citric acids while maintaining a lower titratable acidity. Sequential inoculation was observed to significantly enhance the total polyphenols and flavonoids, as well as the antioxidant capacity (p < 0.05). Specifically, in the synthesis of volatile aroma compounds, sequential inoculation significantly enhanced the richness and diversity of the Huaniu apple cider's aromas, particularly in terms of the concentration of ester compounds (p < 0.05). Principal component analysis further confirmed the superiority of sequential inoculation in terms of aroma component diversity and richness. The findings of this study suggest that sequential inoculation of fermentation with non-Saccharomyces and S. cerevisiae is an effective strategy for optimizing the flavor characteristics of Huaniu apple cider, offering valuable theoretical support and practical guidance for enhancing cider quality and fostering the development of new products.

Gold nanobipyramid colorimetric sensing array for the differentiation of strong aroma-type baijiu with different geographical origins

It is of great significance to quickly and effectively distinguish strong aroma-type baijiu (SAB) with the largest baijiu market share and the most extensive production regions. Colorimetric sensor arrays based on gold nanobipyramids (AuNBPs) with extraordinary plasmonic properties were constructed for the differentiation of SAB from different geographical origins. The sensing strategy was based on silver deposition on different morphologies of AuNBPs under different reducing conditions containing amino or hydroxyl groups. The deposition process can be effective for distinguishing differences in baijiu due to the chemical interaction between the trace ingredients in baijiu and reductants. The colorimetric sensor arrays were implemented for the response of the main ingredients and further used for the differentiation of SAB from different regions by linear discriminant analysis. The results showed that the sensing strategy had excellent performance in distinguishing SAB from different origins, and provides a promising application strategy for baijiu quality control.

Application of Cyclocarya paliurus-Kiwifruit Composite Fermented to Enhance Antioxidant Capacity, Flavor, and Sensory Characteristics of Kiwi Wine

A new fermentation method for kiwi wine was explored by developing the well-known medicinal and edible plant Cyclocarya paliurus (C. paliurus) to create more value with undersized kiwifruits. In this study, the changes in bioactive substances during the C. paliurus-kiwi winemaking process were analyzed on the basis of response surface optimization results, and the antioxidant capacity, aromatic compounds, and sensory quality of the C. paliurus-kiwi composite wine with kiwi wine and two commercial kiwi wines were compared. The results showed that DPPH radical, OH- radical, and ABTS+ scavenging rates remained at over 60.0%, 90.0%, and 70.0% in C. paliurus-kiwi wine, respectively. The total flavonoid content (TFC) and total polyphenol content (TPC) of C. paliurus-kiwi wine were significantly higher than those of the other three kiwi wines. C. paliurus-kiwi wine received the highest score and detected 43 volatile compounds. Ethyl hexanoate, which showed stronger fruity and sweet aromas, was one of the main aroma components of C. paliurus-kiwi wine and different from commercial wines. This wine has a good flavor with a natural and quality feeling of C. paliurus-kiwifruit extract, low-cost processing, and great market potential.

A comparative study of the effect of bacteria and yeasts communities on inoculated and spontaneously fermented apple cider

Understanding bacteria and yeasts communities can reduce unpredictable changes of apple cider. In this study, apple juice inoculated with Saccharomyces cerevisiae WET 136 and fermented spontaneously were compared, the relationships of bacteria, yeasts, organic acids, and volatiles were analyzed. Results showed that microbial diversity affected the fermentation, organic acids and volatiles in apple ciders. In the first four spontaneous fermentation days, LAB (lactic acid bacteria) multiplied and reached 7.89 lg CFU/mL, and then triggered malolactic fermentation (MLF), leading to malic acid decreased by 3880.52 mg/L and lactic acid increased by 4787.55 mg/L. The citric, succinic and fumaric acids content was 2171.14, 701.51 and 8.06 mg/L lower than that in inoculated cider, respectively. Although the yeasts multiplied during spontaneous fermentation, it did not reach 7.50 lg CFU/mL until the 5th day, which led to a long lag period, as well as later and lower production of acetaldehyde and higher alcohols. The inoculated yeast inhibited LAB, acetic acid bacteria, Rahnella, and non-Saccharomyces. Yeasts were the key to produce citric acid, acetaldehyde and 3-methyl-1-butanol in apple cider; while bacteria were closely related to the formation of lactic acid, acetic acid and ethyl acetate. It suggested that low higher alcohols and acetaldehyde can be realized by selecting yeasts, and Leuconostoc pseudomesenteroides can work as candidate to reduce L-malic and citric acids in apple cider.

Sensory descriptive analysis of hard ciders from the Northeast and Mid-Atlantic United States

Although alcoholic or "hard" cider is a beverage of growing popularity throughout the Northeastern and Mid-Atlantic United States (US), the industry lacks a consistent language for describing the sensory quality of its products. The main objective of this research was to explore the sensory attributes that can be used to describe a large representative sample (N = 42 samples) of ciders from Virginia, Vermont, and New York, using classical descriptive analysis (DA). The secondary objective of the research was to determine if cider samples' sensory attributes differ based on extrinsic factors, such as style, packaging, and apple varieties. The study was conducted using a standard DA: 8 panelists were trained for 13 h to develop a lexicon of aroma, taste, and mouthfeel descriptors for 42 cider samples (15 single varietal ciders, 27 blended ciders). Then, subjects evaluated each cider in duplicate for all descriptive attributes in standard sensory-evaluation conditions. Results were analyzed to determine overall differences among the individual cider samples, geographic origins, cider styles, and packaging formats, as well as significant differences across individual attributes. Herein, we report on 29 attributes that can be used to discriminate cider samples, as well as a subset of attributes which differentiate ciders based on extrinsic product variables. These results provide a framework for describing ciders from the Northeast and Mid-Atlantic regions of the US, which may be further generalizable to other North American ciders. As well, these results highlight the potential for more descriptive, sensory-based style guidelines may inspire future research related to cider production practices and terroir.

Screening low-methanol and high-aroma produced yeasts for cider fermentation by transcriptive characterization

The commercial active dry yeast strains used for cider production in China are far behind the requirements of the cider industry development in recent decades. In this study, eight yeasts, including Saccharomyces cerevisiae, Schizosaccharomyces pombe, Pichia bruneiensis, and Pichia kudriavzevii, were screened and assessed by growth performance, methanol production, aroma analysis, and their transcriptive characterization. Saccharomyces cerevisiae strains WFC-SC-071 and WFC-SC-072 were identified as promising alternatives for cider production. Strains WFC-SC-071 and WFC-SC-072 showed an excellent growth capacity characterized by 91.6 and 88.8% sugar utilization, respectively. Methanol production by both strains was below 200 mg/L. Key aroma compounds imparting cider appreciably characteristic aroma increased in cider fermented by strains WFC-SC-071 and WFC-SC-072. RT-qPCR analysis suggested that most genes associated with growth capacity, carbohydrate uptake, and aroma production were upregulated in WFC-SC-071 and WFC-SC-072. Overall, two Saccharomyces cerevisiae strains are the optimal starters for cider production to enable the diversification of cider, satisfy the differences in consumer demand, and promote cider industry development.

A Preliminary Study of Yeast Strain Influence on Chemical and Sensory Characteristics of Apple Cider

During the fermentation of apple juice, yeast metabolism creates complex biosynthetic pathways which produce a range of compounds responsible for the organoleptic qualities of cider. In this study, basic cider quality parameters were measured to investigate the influence of six yeast strains on cider made from three apple varieties (‘Pink Lady’, ‘Sturmer’, and ‘Bulmer’s Norman’). Measurement of pH, titratable acidity, and total phenolic content revealed that yeast can influence cider attributes, albeit variety and season dependent. Descriptive sensory analysis using a trained sensory panel was conducted on cider made from ‘Pink Lady’ apples and the same six yeast strains. The sensory panel significantly differentiated the yeast strains on the attributes of ‘fresh apple’, ‘earthy’ and ‘pear’. Identifying the variety specific influence of individual yeast strains on chemical and sensory characteristics of apple cider will provide cider makers with an enhanced understanding when choosing yeast strains.

Comparative metabolome and transcriptome analyses of the properties of Kluyveromyces marxianus and Saccharomyces yeasts in apple cider fermentation

This study explored the application of Kluyveromyces marxianus and Saccharomyces cerevisiae (commercial and wild type) in the alcoholic fermentation of Fuji apple juice under static conditions. Metabolome analyses revealed that ethyl esters, including ethyl hexanoate, ethyl decanoate, ethyl octanoate, octanoic acid and decanoic acid, were the dominant components in ciders fermented by the Saccharomyces yeasts. In the K. marxianus ciders, ethyl acetate, hexyl acetate, propyl acetate and acetic acid were the most abundant volatiles, suggesting that the cider fermented by K. marxianus might have a fruitier smell. Transcriptome analyses were adapted to gain insight into the differential metabolite patterns between K. marxianus and S. cerevisiae during cider fermentation. GO and KEGG enrichments revealed that the metabolic pathways of glucose, organic acids and amino acids during cider fermentation were quite different between these two yeasts. The K. marxianus strain exhibited a higher rate of glycolysis and ethanol fermentation than did Saccharomyces yeasts under oxygen-limited conditions. It also reduced the metabolic flux of acetate into acetyl-CoA and then into the TCA cycle, increasing the syntheses of ethyl acetate and relevant esters, which may affect its cell growth under anaerobic conditions but enriched the taste and variety of aromas in apple cider.

Fermentation of kiwifruit juice from two cultivars by probiotic bacteria: Bioactive phenolics, antioxidant activities and flavor volatiles

Three commercial lactic acid bacteria (LAB), namely Lactobacillus acidophilus 85 (La85), Lactobacillus helveticus 76 (Lh76) and Lactobacillus plantarum 90 (Lp90), were employed to investigate the effects on the phenolic compounds, antioxidant capacities and flavor volatiles of kiwifruit juices prepared from two cultivars (Actinidia deliciosa cv. Xuxiang and Actinidia chinensis cv. Hongyang). Results showed that both kiwifruit juices were favorable matrices for LAB growth and the colony counts remained above 9.0 log CFU/mL after fermentation. Total phenolics and flavonoids in Xuxiang and Hongyang juices were increased dramatically by Lh76. Correspondingly, antioxidant capacities based on DPPH, ABTS and FRAP methods were improved significantly and positively correlated with protocatechuic acid and catechin contents (p < 0.05), two newly formed phytochemicals in fermented kiwifruit juices. Furthermore, results of hierarchical cluster analysis revealed that flavor profiles were improved significantly by LAB, and there were noticeable differences between fermented Xuxiang and Hongyang juices.

Phenolic compound profiles in Finnish apple (Malus × domestica Borkh.) juices and ciders fermented with Saccharomyces cerevisiae and Schizosaccharomyces pombe strains

The phenolic compounds in juices and ciders made with Saccharomyces cerevisiae or Schizosaccharomyces pombe from eleven Finnish apple cultivars were analyzed using liquid chromatographic and mass spectrometric methods combined with multivariate data analysis. In general, the ciders contained less phenolic compounds than corresponding apple juices. In the studied apple juices and ciders, hydroxycinnamic acids were the most predominant, accounting for around 80% of total phenolic compounds. Apple juices contained more flavonol glycosides and dihydrochalcones whereas cider processing resulted in increased amount of free hydroxycinnamic acids. The contents of individual phenolic compounds were more dependent on the apple cultivars than the yeast species. Certain cultivars contained remarkably higher contents of dihydrochalcones and hydroxycinnamic acids when comparing with other cultivars. Ciders made using S. pombe remained higher contents of procyanidins and (+)-catechin while S. cerevisiae ciders contained higher individual hydroxycinnamic acids, such as 5-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 3-O-p-coumaroylquinic acid, and 4-O-p-coumaroylquinic acid.

Flavour stability of sterilised chickpeas stored in pouches

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.

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Significant sensory changes occur in sterilised chickpeas during 52 weeks storage.

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40 odour-active volatiles are detected in the sterilised chickpeas.

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Sulphur compounds formed during sterilisation change during storage.

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Hay and green attributes are perceived more intense with increased storage time.

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Oxygen permeability of packaging does not impact the sensory quality during storage.

The Impact of the Fermentation Strategy on the Flavour Formation of Ilzer Rose (Malus domestica Borkh.) Apple Wine

The flavour and the volatilome of apple wines made from the Austrian heritage variety Ilzer Rose was in the scope of this study. The apple wines were produced by adopting oenological practises that are not commonly used in fruit wine production. Different fermentation strategies including the addition of enzymes with β-glucosidase activity, addition of a fining agent, maceration of the mash along with mash fermentation were applied. The volatile compounds of the juices as intermediates and the resulting apple wines were analysed using headspace-SPME GC-MS. CATA technique with a well-trained panel was applied for sensory evaluation. The results show that the flavour of single-variety apple wine can be significantly altered by taking oenological measures. High correlations were found between the results of the analytical investigation and the sensory evaluation. Maceration of the mash leads to an increase in the fruity character of the products, also reflected by significantly higher fruit ester quantities in the wine. During mash fermentation, spontaneous malolactic fermentation was induced leading to a product with new, but thoroughly interesting sensory properties of the apple wine. The results of this study demonstrate that the integration of oenological measures may open a wide field to the development of a high diversity in apple wine flavour.

Characterization of Volatile Compounds and Flavor in Spirits of Old Apple and Pear Cultivars from the Balkan Region

This study was conducted with the aim of developing fruit spirits by utilizing old (autochthonous) apple and pear cultivars that can be attractive to both consumers and producers. Consumers of spirits could enjoy the unique flavor, and producers could gain an opportunity for brand development. In total, eight old apple cultivars (Sarija, Žuja, Samoniklica, Prijedorska zelenika, Bobovec, Masnjača, Lijepocvjetka, and Šarenika) and three pear cultivars (Budaljača, Krakača, and Kalićanka) from Bosnia and Herzegovina were used for the spirits production and for characterizing the flavor of distillates. Golden Delicious was used as a representative of commercial apple cultivar. The aroma profile was conducted through the identification of minor volatile organic compounds (VOCs) and the sensory perception of spirits. Analysis of the VOCs was performed by gas chromatography mass spectroscopy (GC/MS) techniques after enrichment via solid-phase microextraction (SPME). Sensory evaluation was performed by 12 trained panelists. Overall, 35 minor volatile compounds were found in spirits: 13 esters, 7 alcohols, 6 acids, 5 terpenes, and 4 aldehydes. Significant differences were detected in the distribution and quantity of the VOCs, which were fruit cultivar-dependent. Spirits made from Šarenika apple cultivar showed the largest amount of all acids, especially short- and medium-chain fatty acids; however, this richness was not correlated with pleasant sensory attributes. Spirits obtained from Prijedorska zelenika and Masnjača apple cultivars had the best sensory attributes. Budeljača and Krakača pears are promising cultivars as flavoring in spirits production.

Authentication Using Volatile Composition: A Proof-of-Concept Study on the Volatile Profiles of Fourteen Queensland Ciders

Although relatively small, the Australian cider industry has experienced significant growth in recent years. One of the current challenges in the industry is the lack of research specific to Australian ciders. Establishing baseline volatile organic compound (VOC) profiles of Australian cider is paramount to developing a better understanding of the industry. This understanding may ultimately be utilized for both the categorization and authentication of existing ciders, and the targeted modification of cider volatiles for the development and improvement of cider quality. This study utilized gas chromatography, coupled with mass spectrometry, to identify key VOCs present in 14 ciders sourced from four different manufacturers in Queensland, Australia. A total of 40 VOCs were identified across the ciders, with significant variation depending on the flavor and manufacturer. Principal component analysis indicated that the ciders were well-separated based on the manufacturer, supporting the prospect of using the volatile composition to discriminate between cider manufacturers. Furthermore, hierarchical cluster analysis highlighted the commonalities and differences in cider composition between different manufacturers, which may be indicative of the varying ingredients and manufacturing processes used to create the ciders. Future studies profiling the volatile composition of larger numbers of Australian ciders are recommended to support the use of this analytical technique for authentication purposes. Likewise, exploration of the relationship between specific processes and VOCs is recommended to fortify an understanding of how to optimize cider production to improve consumer satisfaction.

The Use of Temporal Check-All-That-Apply and Category Scaling by Experienced Panellists to Evaluate Sweet and Dry Ciders

Cider is a growing market in North America, but more studies need to be completed to fully understand ciders’ sensory properties. The primary objective of this study was to identify the differences in the sensory properties of ciders described as “sweet” or “dry” using both static (category scales) and dynamic (temporal check-all-that-apply, TCATA) sensory methodologies. The secondary objective was to evaluate experienced panellists with a familiar methodology (category scales) and an unfamiliar methodology (TCATA). The sweet ciders were characterized by sweet, floral, cooked apple, and fresh apple attributes, and they had a sour aftertaste. The dry ciders were found to be bitter, sour, earthy, and mouldy, and they had a sour and bitter aftertaste. The experienced panellists produced reproducible results using both methodologies; however, they did not find small differences between the cider samples. Future research should investigate a wider range of cider and investigate ciders’ aftertaste. More studies need to be completed on experienced panellists and on when researchers and the food industry should use them.

Apple Fermented Products: An Overview of Technology, Properties and Health Effects

As an easily adapted culture, with overloaded production in some parts of the globe, apples and their by-products are being redirected to pharmaceutical, canning and beverages industries, both alcoholic and non-alcoholic. Fermentation is generally considered to increase the bioavailability of bioactive compounds found in apple, by impacting, through a high degree of changes, the product’s properties, including composition and health-promoting attributes, as well as their sensory profile. Probiotic apple beverages and apple vinegar are generally considered as safe and healthy products by the consumers. Recently, contributions to human health, both in vivo and in vitro studies, of non-alcoholic fermented apple-based products have been described. This review highlighted the advances in the process optimization of apple-based products considering vinegar, cider, pomace, probiotic beverages and spirits’ technologies. The different processing impacts on physical-chemical, nutritional and sensory profiles of these products are also presented. Additionally, the harmful effects of toxic compounds and strategies to limit their content in cider and apple spirits are illustrated. New trends of fermented apple-based products applicability in tangential industries are summarized.

Effect of Saccharomyces cerevisiae and Schizosaccharomyces pombe strains on chemical composition and sensory quality of ciders made from Finnish apple cultivars

Composition of volatile compounds and concentrations of sugars and organic acids were studied in apple ciders produced with Saccharomyces cerevisiae and Schizosaccharomyces pombe yeasts using eleven different Finnish apple cultivars. Moreover, sensory quality of selected ciders was studied using check-all-that-apply test with untrained panelists. Seventy-seven volatile compounds were detected in the samples using HS-SPME-GC-MS. In general, the ciders had higher concentrations of higher alcohols, aldehydes, and acetals whereas the juices contained higher contents of C6-alcohols. Simultaneously, fermentation using S. pombe resulted in lower concentrations of malic acid, ethyl pentanoate, ethyl hexanoate, and volatile acids and higher concentrations of residual sugars compared to S. cerevisiae. Ciders made using S. cerevisiae were characterized as 'alcoholic' and 'yeasty' while S. pombe ciders were more frequently described as 'sweet', 'honey-like', and less rated as sour. Besides the strong effect by the yeasts, apple cultivars had significant effects on the compositional and sensorial properties of apple ciders.

Geographical differentiation of apple ciders based on volatile fingerprint

With the globalization of food trade, it's traceability and genuineness becomes increasingly more difficult. Therefore, it is necessary to develop analytical tools to define the authenticity and genuineness of food-derived products. In the current work, headspace solid-phase microextraction followed by gas chromatography-mass spectrometry (HS-SPME/GC-MS) combined with chemometric tools was used to establish the volatile fingerprint of apple ciders produced in different geographical regions of Madeira Island, in order to define their typicity and to identify putative geographical markers. A total of 143 volatile organic compounds (VOCs) belonging to different chemical families have been identified, of which 28 were found in all apple ciders independently of geographical region. Esters, terpenic and furanic compounds presented on average a higher contribution for the total volatile fingerprint in cider produced in northern region of the Island, whereas alcohols, acids, volatile phenols, carbonyl compounds and lactones in cider from southern region. Considering the relative areas of the VOCs, 43 revealed statistically significant differences (p < 0.001) between geographical regions, and 11 between northern and southern regions. A clear differentiation among cider-producing regions was observed on the developed partial least squares-discriminant analysis (PLS-DA) model. Two alcohols (1-hexanol, 1-octanol), 6 esters (methyl acetate, (Z)-3-hexen-1-ol acetate, ethyl hexanoate, ethyl nonanote, ethyl octanoate, isoamyl octanoate) and 1 terpenic compound (limonene), can be considered putative geographic markers due to their discriminatory ability. The results obtained recognize the specific and typical geographical characteristics of the cider, which will allow the forthcoming guarantee for the construction of a sustainable platform for the establishment of the authenticity and typicality of the regional cider.

Effect of the apple cultivar on cloudy apple juice fermented by a mixture of Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus fermentum

This study aimed to evaluate the fermentation performance of a mixture of Lactobacillus spp. in cloudy apple juices from nine cultivars. The results showed that cultivar influenced most the properties of the fermented cloudy apple juice. The fermented cloudy apple juices made from Changfu had the highest viable bacterial count and acetic acid contents (6.37 × 10⁸ CFU/mL and 2.67 mg/mL, respectively). It also had higher sensory score, second only to Huaniu. The highest total sugar consumption, utilising fructose, glucose, and sucrose (33.07 mg/mL), was seen with Golden Delicious. Qinguan fermented cloudy apple juice had the highest contents of lactic acid (6.74 mg/mL) and total esters (921.36 μg/L); d-limonene also detected in this fermented cloudy apple juice. Of the nine cultivars examined in this study, Changfu, Qinguan, and Golden Delicious were the most suitable for producing fermented cloudy apple juice with better taste, higher viable count and more intense aroma.

Analysis of Volatile Compounds and Sugar Content in Three Polish Regional Ciders with Pear Addition

Aroma plays important part in cider acceptability to the consumer. In this study, techniques such as headspace solid-phase microextraction (HS-SPME), which has been coupled with gas chromatography and mass spectrometry, have been used to assess what changes in the volatilome occur during fermentation of three apple cultivars (Cortland, Gala, Idared) with and without addition of pear (Konferencja) juice addition. Analysis of volatiles has shown that temperature of fermentation, apple variety and pear juice addition have significant influences on the volatile compositions of the acquired ciders. Ciders prepared in laboratory conditions fermented at 15 °C were characterized by a greater share of esters, such as ethyl hexanoate, ethyl decanoate and ethyl dodecanoate, in volatile profile (66.24–79.58%) than ciders fermented at 20 °C (58.81–77.22%). Ciders fermented at a higher temperature were characterized by a greater share of alcohols, such as phenylethyl alcohol and hexan-1-ol (18.34–36.7%) than ciders fermented at a lower temperature (16.07–25.35%). In the ciders prepared from pear (20% w/w) and apple (80% w/w) juice, the presence of esters, such as ethyl (2E, 4Z)-deca-2,4-dienoate, characterized by a pear aroma, could be noted.

Monitoring Cider Aroma Development throughout the Fermentation Process by Headspace Solid Phase Microextraction (HS-SPME) Gas Chromatography–Mass Spectrometry (GC-MS) Analysis

Volatile organic compounds (VOCs) play a crucial role in cider quality. Many variables involved in the fermentation process contribute to cider fragrance, but their relative impact on the finished odor remains ambiguous, because there is little consensus on the most efficient method for cider volatile analysis. Herein, we have optimized and applied a headspace solid phase microextraction gas chromatography–mass spectrometry (HS-SPME GC-MS) method for the chemical analysis of cider VOCs. We determined that the 30 min exposure of a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) solid phase microextraction (SPME) fiber at 40 °C yielded detection of the widest variety of VOCs at an extraction efficiency >49% higher than comparable fibers. As a proof-of-concept experiment, we utilized this method to profile cider aroma development throughout the fermentation process for the first time. The results yielded a very practical outcome for cider makers: a pre-screening method for determining cider quality through the detection of off-flavors early in the fermentation process. The aroma profile was found to be well established 72 h after fermentation commenced, with major esters varying by 18.6% ± 4.1% thereafter and higher alcohols varying by just 12.3% ± 2.6%. Lastly, we analyzed four mature ciders that were identically prepared, save for the yeast strain. Twenty-seven key VOCs were identified, off-flavors (4-ethylphenol and 4-ethyl-2-methoxyphenol) were detected, and odorants were quantified at desirable concentrations when compared to perception thresholds. VOCs varied considerably following fermentation with four novel strains of S. cerevisiae, evidencing the central importance of yeast strain to the finished cider aroma.

Characterization of metabolite profiles of white and green spears of asparagus officinalis L. from Caoxian, East China

China is the largest planting country of asparagus (Asparagus officinalis L.) in the world. Caoxian, as the famous asparagus township in China, enjoys a reputation for producing asparagus with high yield and good quality, due to its unique geological characteristic. In this study, a method of reverse-phase ultraperformance liquid chromatography coupled with electrospray tandem mass spectrometry (RP-UPLC-ESI-MS/MS) was established for profiling metabolites from three segments (tip, mid, and base) of 'Caoxian white and green Asparagus'. A total of 114 metabolites were identified, among them, 43 were found for the first time in this vegetable. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) was applied to provide an overview of the metabolite profiles of Caoxian asparagus and to separate different segments of spears. The variables most decisive to discriminate among segments included 9 of the metabolites tentatively identified. This study will help to improve the protection of Caoxian asparagus geographical indication.

Chemical composition, sensorial properties, and aroma-active compounds of ciders fermented with Hanseniaspora osmophila and Torulaspora quercuum in co- and sequential fermentations

In this study, apple juice was fermented using Hanseniaspora osmophila X25-5 in pure culture as well as mixed culture with Torulaspora quercuum X24-4, which was inoculated simultaneously or sequentially. H. osmophila inhibited the growth of T. quercuum, while T. quercuum had little effect on the growth of H. osmophila. The simultaneous fermentation consumed relatively more sugar and resulted in the highest ethanol content. The production of organic acids varied depending on the yeast species employed and inoculation modality. Esters and alcohols were the main volatile families produced during fermentation, while ethyl esters and terpenes contributed most to the temperate fruity aroma. Gas chromatography-olfactometry (GC-O) showed that 3-methyl-1-butanol, ethyl 2-methylbutanoate, phenylethyl alcohol, β-phenethyl acetate, and β-damascenone were the most potent odorants in all samples. This study suggested that simultaneous fermentation with H. osmophila and T. quercuum might represent a novel strategy for the future production of cider.

From Byproduct to Resource: Fermented Apple Pomace as Beer Flavoring

One of the main struggles of the large-scale apple processing industry is pomace disposal. One solution for this problem is to convert this waste into a resource. Apple pomace could be used as a substrate for lactic acid bacteria and could induce the formation of a more complex aroma profile, making this fermented product an innovative aromatizer for alcoholic beverages, such as beer. In this study, for the first time, the effect of lacto-fermented apple pomace addition in beer was evaluated. Three bacterial strains (Lactobacillus rhamnosus 1473 and 1019, and L. casei 2246) were tested for apple pomace fermentation, and L. rhamnosus 1473 was the strain that best modified the aromatic profile. The addition of fermented apple pomace to beer increased the complexity of the aroma profile, demonstrating the potential of this byproduct as an aromatizer in the alcoholic beverage industry.

An HS-SPME-GC-MS Method for Profiling Volatile Compounds as Related to Technology Used in Cider Production

Volatile aromatic compounds have a major impact on the final organoleptic properties of cider, and their profiles are influenced by a number of parameters that are closely related to production technologies, especially with regard to the raw material, the microorganism used and the fermentation process. In this work, the profiles of volatile compounds (4 fatty acids, 6 higher alcohols and 12 esters) from 34 European ciders were studied using HS-SPME-GC-MS. Volatiles were isolated by HS-SPME using a CAR/PDMS fiber. Analytical data were statistically evaluated using principal component analysis, and differences in composition of volatiles between cider produced using "intensified" technologies and that of ciders produced by traditional production processes were demonstrated. This difference was mainly due to varying contents of some higher alcohols (2-methylpropanol, isoamyl alcohols, hexanol, and butane-2,3-diol) and esters (ethyl 2-methylbutanoate, butylacetate, and hexyl acetate).