Aromatic Higher Alcohols in Wine: Implication on Aroma and Palate Attributes during Chardonnay Aging

The higher alcohols 2-phenylethanol, tryptophol, and tyrosol are a group of yeast-derived compounds that have been shown to affect the aroma and flavour of fermented beverages. Five variants of the industrial wine strain AWRI796, previously isolated due to their elevated production of the ‘rose-like aroma’ compound 2-phenylethanol, were characterised during pilot-scale fermentation of a Chardonnay juice. We show that these variants not only increase the concentration of 2-phenylethanol but also modulate the formation of the higher alcohols tryptophol, tyrosol, and methionol, as well as other volatile sulfur compounds derived from methionine, highlighting the connections between yeast nitrogen and sulfur metabolism during fermentation. We also investigate the development of these compounds during wine storage, focusing on the sulfonation of tryptophol. Finally, the sensory properties of wines produced using these strains were quantified at two time points, unravelling differences produced by biologically modulating higher alcohols and the dynamic changes in wine flavour over aging.     

Terroir Effect on the Phenolic Composition and Chromatic Characteristics of Mencía/Jaen Monovarietal Wines: Bierzo D.O. (Spain) and Dão D.O. (Portugal)

‘Mencía’/‘Jaen’ it’s an important red grape variety, exclusive of the Iberian Peninsula, used in wine production namely in Bierzo D.O. and Dão D.O., respectively. This work evaluates the effect of the two different “terroirs” on the phenolic composition and chromatic characteristics of ‘Mencía’/‘Jaen’ monovarietal wines produced at an industrial scale in the same vintage. Using Principal Component Analysis (PCA), Partial Least Squares-Discrimination Analysis (PLS-DA), and Orthogonal PLS-DA (OPLS-DA) it was found that peonidin-3-coumaroylglucoside, petunidin-3-glucoside, malvidin-3-coumaroylglucoside, peonidin-3-glucoside, malvidin-3-acetylglucoside, malvidin-3-glucoside, and ferulic acid were the phenolic compounds with the highest differences between the two regions. PLS regression allowed to correlate the differences in lightness (L*) and redness (a*) of wines from ‘Jaen’ and ‘Mencía’ to differences in colored anthocyanins, polymeric pigments, total pigments, total anthocyanins, cyanidin-3-acetylglucoside, delphinidin-3-acetylglucoside, delphinidin-3-glucoside, peonidin-3-coumaroylglucoside, petunidin-3-glucoside and malvidin-3-glucoside in wines, and the colorless ferulic, caffeic, and coutaric acids, and ethyl caffeate. The wines a* values were more affected by colored anthocyanins, ferulic acid, total anthocyanins, delphinidin-3-acetylglucoside, delphinidin-3-glucoside and petunidin-3-acetylglucoside, and catechin. The positive influence of ferulic acid in the a* values and ferulic, caffeic, coutaric acids, and ethyl caffeate on the L* values can be due to the co-pigmentation phenomena. The higher dryness and lower temperatures during the September nights in this vintage might explain the differences observed in the anthocyanin content and chromatic characteristics of the wines.     

The Phenolics and Antioxidant Properties of Black and Purple versus White Eggplant Cultivars

The total phenolic content, anthocyanins, phenolic acids, antioxidant capacity and α-amylase inhibitory activity of black (Aydin Siyahi), purple (Kadife Kemer) and white (Trabzon Kadife) eggplants grown in Turkey were subjected to a comparative investigation. The black cultivar exhibited the highest total phenolic (17,193 and 6552 mg gallic acid equivalent/kg fw), flavonoid (3019 and 1160 quercetin equivalent/kg fw) and anthocyanin (1686 and 6167 g delphinidin-3-O-glucoside equivalent/kg fw) contents in crude extracts of the peel and pulp. The majority of the caffeic acid was identified in the ester (2830 mg/kg fw) and ester-bound (2594 mg/kg fw) forms in the peel of ‘Kadife Kemer’ and in the glycoside form (611.9 mg/kg fw) in ‘Aydin Siyahi’, as well as in the pulp of these two eggplants. ‘Kadife Kemer’ (purple eggplant) contained the majority of the chlorogenic acid in free form (27.55 mg/kg fw), compared to ‘Aydin Siyahi’ in the ester (7.82 mg/kg fw), glycoside (294.1 mg/kg dw) and ester-bound (2.41 mg/kg fw) forms. The eggplant cultivars (peel and pulp, mg/kg fw) exhibited a relatively high delphinidin-3-O-rutinoside concentration in the peel of ‘Aydin Siyahi’ (avg. 1162), followed by ‘Kadife Kemer’ (avg. 336.6), and ‘Trabzon Kadife’ (avg. 215.1). The crude phenolic extracts of the eggplants exhibited the highest antioxidant capacity values (peel and pulp, µmoL Trolox equivalent/kg fw) of 2,2-diphenyl-1-picrylhydrazyl (DPPH, 8156 and 2335) and oxygen radical absorbance capacity (ORAC, 37,887 and 17,648). The overall results indicate that black and purple eggplants are the cultivars with greater potential benefits in terms of their phenolics and antioxidant values than the white eggplant.     

HS–SPME–GC–MS and Electronic Nose Reveal Differences in the Volatile Profiles of Hedychium Flowers

Floral fragrance is one of the most important characteristics of ornamental plants and plays a pivotal role in plant lifespan such as pollinator attraction, pest repelling, and protection against abiotic and biotic stresses. However, the precise determination of floral fragrance is limited. In the present study, the floral volatile compounds of six Hedychium accessions exhibiting from faint to highly fragrant were comparatively analyzed via gas chromatography–mass spectrometry (GC–MS) and Electronic nose (E-nose). A total of 42 volatile compounds were identified through GC–MS analysis, including monoterpenoids (18 compounds), sesquiterpenoids (12), benzenoids/phenylpropanoids (8), fatty acid derivatives (2), and others (2). In Hedychium coronarium ‘ZS’, H. forrestii ‘Gaoling’, H. ‘Jin’, H. ‘Caixia’, and H. ‘Zhaoxia’, monoterpenoids were abundant, while sesquiterpenoids were found in large quantities in H. coccineum ‘KMH’. Hierarchical clustering analysis (HCA) divided the 42 volatile compounds into four different groups (I, II, III, IV), and Spearman correlation analysis showed these compounds to have different degrees of correlation. The E-nose was able to group the different accessions in the principal component analysis (PCA) corresponding to scent intensity. Furthermore, the pattern-recognition findings confirmed that the E-nose data validated the GC–MS results. The partial least squares (PLS) analysis between floral volatile compounds and sensors suggested that specific sensors were highly sensitive to terpenoids. In short, the E-nose is proficient in discriminating Hedychium accessions of different volatile profiles in both quantitative and qualitative aspects, offering an accurate and rapid reference technique for future applications.     

Effect of the aging on lees and other alternative techniques on the low molecular weight phenols of Tempranillo red wine aged in oak barrels

The effect of different alternative techniques to the traditional aging on lees on the low molecular weight phenolic compounds of red wines was study as well as their evolution during the aging in oak wood barrels for six months. The study was carried out with Tempranillo red grapes from two consecutive vintages. The techniques assayed were the traditional aging on lees with or without the addition of exogenous β-glucanase enzymes, the use of yeast derivative preparations also with or without the addition of exogenous β-glucanase enzymes, the micro-oxygenation applied together with the aging on lees, and the use of non-toasted oak wood chips.     

Sea Buckthorn Leaf Powders: The Impact of Cultivar and Drying Mode on Antioxidant,Phytochemical, and Chromatic Profile of Valuable Resource

Sea buckthorn (Hippophae rhamnoides L. (HR)) leaf powders are the underutilized, promising resource of valuable compounds. Genotype and processing methods are key factors in the preparation of homogenous, stable, and quantified ingredients. The aim of this study was to evaluate the phenolic, triterpenic, antioxidant profiles, carotenoid and chlorophyll content, and chromatic characteristics of convection-dried and freeze-dried HR leaf powders obtained from ten different female cultivars, namely ‘Avgustinka’, ‘Botaniceskaja Liubitelskaja’, ‘Botaniceskaja’, ‘Hibrid Percika’, ‘Julia’, ‘Nivelena’, ‘Otradnaja’, ‘Podarok Sadu’, ‘Trofimovskaja’, and ‘Vorobjovskaja’. The chromatic characteristics were determined using the CIELAB scale. The phytochemical profiles were determined using HPLC-PDA (high performance liquid chromatography with photodiode array detector) analysis; spectrophotometric assays and antioxidant activities were investigated using ABTS (2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) and FRAP (ferric ion reducing antioxidant power) assays. The sea buckthorn leaf powders had a yellowish-green appearance. The drying mode had a significant impact on the total antioxidant activity, chlorophyll content, and chromatic characteristics of the samples; the freeze-dried samples were superior in antioxidant activity, chlorophyll, carotenoid content, and chromatic profile, compared to convection-dried leaf powder samples. The determined triterpenic and phenolic profiles strongly depend on the cultivar, and the drying technique had no impact on qualitative and quantitative composition. Catechin, epigallocatechin, procyanidin B3, ursolic acid, α-amyrin, and β-sitosterol could be used as quantitative markers in the phenolic and triterpenic profiles. The cultivars ‘Avgustinka’, ‘Nivelena’, and ‘Botaniceskaja’ were superior to other tested cultivars, with the phytochemical composition and antioxidant activity.     

Content of Phenolic Compounds and Organic Acids in the Flowers of Selected Tulipa gesneriana Cultivars

The study focused on the determination of phenolic acids, flavonoids and organic acids in five tulip cultivars ‘Barcelona’, ‘Columbus’, ‘Strong Gold’, ‘Super Parrot’ and ‘Tropicana’. The cultivars grown in field and in a greenhouse were exposed after cutting to different times of storage (0, 3 and 6 days). The phenolic profile contained 4-hydroxybenzoic, 2,5-dihydroxybenzoic, gallic, vanillic, syringic, salicylic, protocatechuic, trans-cinnamic, p-coumaric, caffeic, ferulic, chlorogenic and sinapic acids, as well as quercetin, rutin, luteonin, catechin and vitexin. The mean phenolic acid content was in the following order: ‘Columbus’ and ‘Tropicana’ > ’Barcelona’ > ’Strong Gold’ > ’Super Parrot’, while the levels of flavonoids were as follows: ‘Strong Gold’ > ’Barcelona’ > ’Tropicana’ > ’Columbus’ > ’Super Parrot’. The highest content of phenolic acids was confirmed for Columbus and Tropicana, while the lowest was for Super Parrot. However total phenolic content was very similar, observed between the place of cultivation, time of storage and cultivars. Malonic, succinic, acetic and citric acids were the major organic acid components in tulip petals. More organic acids (except malonic) were accumulated in tulip petals from fields than those from the greenhouse, while changes during storage were strictly correlated with cultivars.     

Rapid Discrimination of Citrus reticulata ‘Chachi’ by Electrospray Ionization–Ion Mobility–High-Resolution Mass Spectrometry

A common idea is that some dishonest businessmen often disguise Citrus reticulata Blanco varieties as Citrus reticulata ‘Chachi’, which places consumers at risk of economic losses. In this work, we combined high-resolution ion mobility (U-shaped mobility analyzer) with high-resolution mass spectrometry to rapidly distinguish Citrus reticulata ‘Chachi’ from other Citrus species. The samples were analyzed directly through simple extraction and the analytes were separated in one second. It only took about 1 min to perform a cycle of sample analysis and data acquisition. The results showed that polymethoxylated flavones and their isomers were separated easily by the ion mobility analyzer and preliminarily identified according to the accurate mass. Moreover, the collision cross-section values of all analytes, which could be used as auxiliary parameters to characterize and identify the compounds in the samples, were measured. Twenty-four samples were grouped as two clusters by multivariate analysis, which meant that Citrus reticulata ‘Chachi’ could be effectively differentiated. It was confirmed that the developed method had the potential to rapidly separate polymethoxylated flavones and distinguish between Citrus reticulata ‘Chachi’ and other Citrus reticulata Blanco varieties.     

Evaluation of Leaf Mineral,Flavonoid, and Total Phenolic Content in Spider Plant Germplasm

Spider plant (Cleome gynandra L.) is an important leafy vegetable that grows naturally in many parts of the world. The leaves are highly nutritious and are used mainly for human consumption. The mineral content and phenolic compounds of 17 genotypes (local and exotic) of spider plant and four standards (swiss chard, jute mallow, cowpea, and pumpkin) were investigated. Leaf samples were harvested from plants raised at Thohoyandou, South Africa. Exotic genotypes were superior to local genotypes for most of the minerals. Swiss chard possessed significantly high levels of some minerals such as iron and manganese in comparison with exotic spider plant genotypes. The calcium content in the local (‘MP-B-3-CG’) and exotic (‘GPS’) genotypes was >30.0% and >60.0% higher than in swiss chard, respectively. Total phenolics among spider plant genotypes ranged from 9.86 to 12.21 mg GAE/g DW and were superior to pumpkin. In addition, the spider plant genotypes varied significantly in the antioxidant capacity as estimated by the 2,2 diphenyl-1-picrylhydrazyl method and ferric-reducing antioxidant power. The main flavonoid in the leaves of spider plant genotypes was quercetin-3-rutinoside. Crotonoside (glycoside) was detected in all the spider plant genotypes and swiss chard. A positive correlation was observed between total phenolic content and each of the three flavonoids. The PCA biplot associated exotic genotypes (‘ML-SF-29′, ‘PS’, ‘TZ-1’, and ‘GPS’) and local genotypes (‘ML-3-KK’, ‘ML-13-SDM’, and ‘ML-12-TMP’) with high Al, Fe, Zn, N, and TPC. Cluster analysis indicated high “distant groups” between exotic and local genotypes of spider plant. These results indicated that some of the local germplasm of spider plant was largely inferior to the exotic germplasm in terms of their mineral composition but contained considerable quantities of quercetin-3-rutinoside, particularly in the local genotypes ‘MP-B-2-CG’ and ‘MP-B-1-CG’. There is a need for genetic improvement of the local germplasm in some of the minerals particularly to benefit the end-users.     

Chemical Compositions and Antioxidant Activities of Essential Oils,and Their Combinations,Obtained from Flavedo By-Product of Seven Cultivars of Sicilian Citrus aurantium L.

In this work, seven Citrus aurantium essential oils (EOs) derived from flavedo of cultivars ‘Canaliculata’, ‘Consolei’, ‘Crispifolia’, ‘Fasciata’, ‘Foetifera’, ‘Listata’, and ‘Bizzaria’ were investigated. EOs were also combined in 1:1 (v/v) ratio to identify possible synergism or antagonism of actions. GC-MS analysis was done to investigate Eos’ phytochemical profiles. The antioxidant activity was studied by using a multi-target approach based on FRAP, DPPH, ABTS, and β-carotene bleaching tests. A great difference was observed in EOs’ phytochemical profiles. d-limonene (33.35–89.17%) was the main monoterpene hydrocarbon, and α-Pinene, β-myrcene, and β-linalool were identified in almost all samples. Among EOs, only C3 showed high quantitative and qualitative variability in its chemical composition. The chemical diversity of EOs was also demonstrated by PCA and HCA statistical analysis. Samples C2, C4, C5, C6, and C7 were statistically similar to each other, while C1 and C3 were characterized as having a different amount of other compounds and oxygenated monoterpenes, respectively, with respect to the other EOs mentioned. The global antioxidant score (GAS) revealed that among the tested EOs, C. aurantium ‘Fasciata’ EO had the highest antioxidant potential, with a GAS value of −0.47, whereas among combinations, the EO obtained by mixing ‘Canaliculata’ + ‘Bizzaria’ was the most active. Comparison by theoretical and real data on inhibitory concentration (IC₅₀) and FRAP values did not reveal any significant effect of synergism or antagonism of actions to be valid in all biological applied tests. These findings, considered together, represent an important starting point to understand which compounds are responsible for the activities and their future possible industrial application.     

Rapid Preparation of Mesoporous Methylsilsesquioxane Aerogels by Microwave Heating Technology

Microwave heating technology is known as an alternative to traditional gas and electric heating sources. In this work, mesoporous methylsilsesquioxane (MSQ) aerogels were prepared via a sol–gel process accompanied by microwave heating technology, and microwave heating was used in the gelation of sol and the drying of wet gels, respectively. The effects of hexadecyltrimethylammonium chloride (CTAC) as a surfactant and template, hydrochloric acid (HCl) as a catalyst, ethanol as a solvent, sodium hydroxide (NaOH) as a gelation agent, and microwave power on the pore structure of as-prepared MSQ aerogels were investigated in detail. Microwave heating at low power results in the acceleration of sol–gel transition and achieves the gelation within a few minutes. Appropriate amounts of chemical reagents and microwave heating at high power allow the preparation of mesoporous MSQ aerogels with a BET-specific surface area of 681.6 m²·g⁻¹ and a mesopore size of 19 nm, and the resultant MSQ aerogel still has a BET specific surface area as high as 134 m²·g⁻¹ after heat treatment at 600 °C for 2 h, showing high thermal stability. The MSQ aerogels/fibre composite possesses a low thermal conductivity of 0.039 W/(m·k)⁻¹, displaying good thermal insulation. Microwave heating technology is a promising heating method for the preparation of other aerogels.     

The Potential of Virgin Olive Oil from cv. Chondrolia Chalkidikis and Chalkidiki (Greece) to Bear Health Claims according to the European Legislation

The European food legislation authorizes the use of certain health claims based on a scientific basis. This study aimed to evaluate the fatty acid, tocopherol, and polar phenol composition of virgin olive oil (VOO) from cv. Chondrolia Chalkidikis and Chalkidiki regarding the fulfillment of official requirements for the health claims of ‘oleic acid’, ‘vitamin E’, and ‘olive oil polyphenols’. The examination of representative industrial VOOs from 15 olive mills of the Chalkidiki regional unit showed that the two cultivars yield oils contained the necessary concentrations of the responsible bioactive compounds. This evidence was further substantiated by a four harvest study whereby olives from different maturity stages were sampled from three olive groves. Oils were extracted at a laboratory scale and examined for their content in the above-mentioned three categories of constituents. Oils produced at industrial scale from olives harvested on the ‘technological optimum’ stage according to the olive grove proprietor were also analyzed. Extra virgin olive oil of the studied cultivars can safely bear the generic claims for ‘oleic acid’ and ‘vitamin E’. The cultivars present great potential regarding the total hydroxytyrosol and tyrosol content of the extracted oil required to attain the third health claim that may be influenced negatively by manufacturing practices.     

The Content of Phenolic Compounds and Organic Acids in Two Tagetes patula Cultivars Flowers and Its Dependence on Light Colour and Substrate

The main focus of the study was to determine the content of phenolic acids, flavonoids, and organic acids in the flowers of Tagetes patula ‘Petite Gold’ and ‘Petite Orange’. The growth of the plants was assessed depending on the cultivation conditions. The above plants were illuminated with white light, whereas the ‘Petite Gold’ ones with white light enhanced with blue or red light. Both cultivars grew in a two-level-mineral compounds organic substrate. The research showed that the French marigold flowers were rich in phenolic compounds and organic acids. The ‘Petite Gold’ flowers had more bioactive compounds compared with the ‘Petite Orange’ flowers. Three flavonoids, 10 phenolic acids and seven organic acids were found in the ‘Petite Gold’ flowers. The artificial lighting used during the cultivation of the plants showed diversified influence on the content of organic compounds in their flowers. The measurements of the plants’ morphological traits and the number of inflorescences showed that illumination with red light resulted in a better effect. Large plants with numerous inflorescences grew in the substrate with a lower content of nutrients.     

High Throughput Identification of the Potential Antioxidant Peptides in Ophiocordyceps sinensis

Ophiocordyceps sinensis, an ascomycete caterpillar fungus, has been used as a Traditional Chinese Medicine owing to its bioactive properties. However, until now the bio-active peptides have not been identified in this fungus. Here, the raw RNA sequences of three crucial growth stages of the artificially cultivated O. sinensis and the wild-grown mature fruit-body were aligned to the genome of O. sinensis. Both homology-based prediction and de novo-based prediction methods were used to identify 8541 putative antioxidant peptides (pAOPs). The expression profiles of the cultivated mature fruiting body were similar to those found in the wild specimens. The differential expression of 1008 pAOPs matched genes had the highest difference between ST and MF, suggesting that the pAOPs were primarily induced and play important roles in the process of the fruit-body maturation. Gene ontology analysis showed that most of pAOPs matched genes were enriched in terms of ‘cell redox homeostasis’, ‘response to oxidative stresses’, ‘catalase activity’, and ‘ integral component of cell membrane’. A total of 1655 pAOPs was identified in our protein-seqs, and some crucial pAOPs were selected, including catalase, peroxiredoxin, and SOD [Cu–Zn]. Our findings offer the first identification of the active peptide ingredients in O. sinensis, facilitating the discovery of anti-infectious bio-activity and the understanding of the roles of AOPs in fungal pathogenicity and the high-altitude adaptation in this medicinal fungus.     

Nutraceutical Content and Genetic Diversity Share a Common Pattern in New Pomegranate Genotypes

The nutraceutical value of pomegranate in the treatment of many diseases is well-documented and is linked to its richness in phenolic compounds. This study aims to evaluate the nutraceutical and genetic diversity of novel pomegranate genotypes (G1–G5) in comparison to leading commercial pomegranate varieties, i.e., ‘Wonderful’, ‘Primosole’, ‘Dente di Cavallo’ and ‘Valenciana’. Morphometric measurements were carried out on fruits, accompanied by chemical characterization (total phenolic content, antioxidant activity, carbohydrates and minerals) and the development of four new polymorphic SSR markers involved in the flavonoid pathway. The cultivars displayed a marked variability in the weight and shape of the fruits, as well as in the weight of the arils and juice yield. The highest level of total phenolic content and antioxidant activity was found in ‘Wonderful’ and G4, while the lowest was in ‘Dente di Cavallo’. Furthermore, the results showed that pomegranate juice is an excellent source of minerals, especially potassium, which plays a key role in organ functioning. The new flavonoid-related markers effectively differentiated the cultivars with the same diversity pattern as morpho-chemical characterization, so the SSRs developed in the present study can be used as a rapid tool for the identification of pomegranate cultivars with relevant nutraceutical traits, such as the new genotypes investigated.     

Comparative Assessment of Phytochemical Compounds and Antioxidant Properties of Kernel Oil from Eight Sour Cherry (Prunus cerasus L.) Cultivars

New plant oils as a potential natural source of nutraceutical compounds are still being sought. The main components of eight cultivars (‘Koral’, ‘Lucyna’, ‘Montmorency’, ‘Naumburger’, ‘Wanda’, ‘Wigor’, ‘Wołyńska’, and ‘Wróble’) of sour cherry (Prunus cerasus L.) grown in Poland, including crude fat, protein, and oil content, were evaluated. The extracted oils were analysed for chemical and biological activity. The oils had an average peroxide value of 1.49 mEq O₂/kg, acid value of 1.20 mg KOH/g, a saponification value of 184 mg of KOH/g, and iodine value of 120 g I₂/100 g of oil. The sour cherry oil contained linoleic (39.1–46.2%) and oleic (25.4–41.0%) acids as the major components with smaller concentrations of α-eleostearic acid (8.00–15.62%), palmitic acid (5.45–7.41%), and stearic acid (2.49–3.17%). The content of sterols and squalene varied significantly in all the studied cultivars and ranged between 336–973 mg/100 g and 66–102 mg/100 g of oil. The contents of total tocochromanols, polyphenols, and carotenoids were 119–164, 19.6–29.5, and 0.56–1.61 mg/100 g oil, respectively. The cultivar providing the highest amounts of oil and characterised by the highest content of PUFA (including linoleic acid), plant sterols, α-and β-tocopherol, as well as the highest total polyphenol and total carotenoids content was been found to be ‘Naumburger’. The antioxidant capacity of sour cherry kernel oils, measured using the DPPH^• and ABTS^•+ methods, ranged from 57.7 to 63.5 and from 38.2 to 43.2 mg trolox/100 g oil, respectively. The results of the present study provide important information about potential possibilities of application of Prunus cerasus kernel oils in cosmetic products and pharmaceuticals offering health benefits.     

Evaluation of Physiological Characteristics,Soluble Sugars,Organic Acids and Volatile Compounds in ‘Orin’ Apples (Malus domestica) at Different Ripening Stages

‘Orin’ is a popular apple cultivar, which has a yellow-green appearance, pleasant taste, and unique aroma. However, few studies on the fruit quality characteristics of ‘Orin’ apples have been reported before. In this study, changes of the physiological characteristics were measured at different ripening stages, and the soluble sugars and organic acids were determined by high-performance liquid chromatography (HPLC). Volatile compounds were identified using the headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). During the fruit ripening, the ‘Orin’ apple fruit weight, size, and total soluble solid were gradually increased by contrast with the titratable acidity, and the firmness decreased. The content of four soluble sugars reached the maximum at the 180 days after full bloom (DAFB) stage. Malic acid was measured as the most abundant organic acid in ‘Orin’ apples. Ethyl butyrate, hexyl propanoate, hexyl acetate and butyl acetate belonging to esters with high odor activity values (OAVs) could be responsible for the typical aroma of ‘Orin’ apples. The aim of this work was to provide information on the flavor characteristics of ‘Orin’ apples and promote this apple cultivar for marketing and processing in the future.     

Sensory Quality Evaluation of Korla Pear from Different Orchards and Analysis of Their Primary and Volatile Metabolites

Metabolites play vital roles in shaping the quality of fresh fruit. In this study, Korla pear fruit harvested from twelve orchards in South Xinjiang, China, were ranked in sensory quality by fuzzy logic sensory evaluation for two consecutive seasons. Then, gas chromatography-mass spectrometry (GC-MS) was applied to determine the primary metabolites and volatile compounds. Sensory evaluation results showed that the panelists were more concerned about ‘mouth feel’ and ‘aroma’ than about ‘fruit size’, ‘fruit shape’ and ‘peel color’. In total, 20 primary metabolites and 100 volatiles were detected in the pear fruit. Hexanal, (E)-2-hexenal, nonanal, d-limonene, (Z)-3-hexen-1-yl acetate and hexyl acetate were identified as the major volatile compounds. Correlation analysis revealed that l-(+)-tartaric acid, hexanoic acid, trans-limonene oxide and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate were negatively correlated with sensory scores. Furthermore, OPLS-DA results indicated that the fruit from three orchards with lower ranks in quality could be distinguished from other samples based on the contents of l-(+)-tartaric acid and other eight metabolites, which were all associated with ‘mouth feel’ and ‘aroma’. This study reveals the metabolites that might be closely associated with the sensory quality attributes of Korla pear, which may provide some clues for promoting the fruit quality in actual production.