Dominant Organic Acid Research Articles

Comparison of Some Parts of Cotoneaster coriaceus Franch. Plant in Terms of Phytochemicals and Antioxidant Capacity

Cotoneaster spp. is a plant belonging to the Rosaceae family, which includes different genera and taxa. It is a woody plant that grows from shrubs to trees depending on its height (between 0.2-20 m) and grows in the temperate areas of Europe, North Africa and Asia. Many Cotoneaster species have become highly popular ornamental plants due to their striking leaves, dense flowers, and bright red-black fruits. These species have been used traditionally for the treatment of numerous diseases due to their rich bioactive components present in both their above-ground and below-ground parts. This study investigates the phytochemical and antioxidant properties of the above-ground parts of Cotoneaster coriaceus Franch., including its fruits, stems, and leaves. For this purpose, total phenolic content (TPC) and DPPH radical scavenging activity, organic acid and sugar profile, and mineral distributions were determined. According to the results, the highest amounts of macro-minerals identified were potassium (K) and calcium (Ca), while iron (Fe) and boron (B) were the predominant micro-minerals. The dominant organic acid in the fruit was malic acid, while succinic acid was prevalent in the stems and leaves. Sucrose and fructose, the sugars detected in the fruit, were found in equal levels in the stems and leaves. Fructose was identified as the dominant sugar in the leaves. It was determined that the fruit, stem, and leave parts of the Cotoneaster coriaceus Franch. plant species were rich in TPC, with the stems exhibiting higher antioxidant capacity.

Characterisation of wild red raspberry ecotypes in Northern Anatolia: Insights into sensory, biochemical and antioxidant properties

ABSTRACT Red raspberries are among the most significant wild edible fruits (WEFs) in Türkiye, thriving in cold to warm temperate regions across the country. This study focuses on 11 wild red raspberry ecotypes sampled from the Northern Anatolia region, examining their sensory, biochemical and antioxidant properties. Sensory analysis was used to compare ecotypes based on aroma, taste and juiciness. Biochemical assessments included soluble solid content (SSC), vitamin C amount, organic acids, total anthocyanins (TA), total phenolic content (TPC), total flavonoid content and total antioxidant capacity. The Ferric Reducing Antioxidant Power (FRAP) assay measured antioxidant capacity. Despite similar growing conditions, significant variations were observed among ecotypes and across years. In the first year, fruit weights ranged from 1.04 g to 1.33 g, and in the second year, they ranged from 0.97 g to 1.27 g. Fruit chroma values ranged between 26.11 and 33.70 in 2021, and 23.17 and 30.19 in 2022. Vitamin C exhibited considerable variability, ranging from 29.3 mg · 100 g−1 to 44.4 mg · 100 g−1 across ecotypes and years. TPC, total anthocyanin content (TAC) and total flavonoid content ranged from 164 mg to 390 mg gallic acid equivalent (GAE) · 100 g−1, 17.3 mg to 33.2 mg cyanidin-3-glucoside equivalent · 100 g−1 and 10.3 mg to 17.6 mg quercetin equivalent (QE) · 100 g−1, respectively, in both years. Citric acid emerged as the dominant organic acid across all ecotypes. Notably, the ecotypes V-4, V-8, V-3 and V-10 showcased larger, more appealing fruits suitable for fresh consumption, whereas V-3 and V-5 presented sweeter fruits ideal for processing. Additionally, the ecotypes V-6, V-7 and V-11 displayed higher levels of health-promoting compounds, such as TPC and antioxidant capacity, suggesting their potential as functional foods and valuable sources of natural antioxidants in the future.

The dynamic changes and correlations between biochemical properties, flavor and microbial community during fermentation of asparagus by-products

Asparagus by-products are the promising resource that urgently need to be re-valorized. This study investigated the dynamic changes in physicochemical properties, organic acids, free amino acids, volatile flavor compounds, microbial succession, and their correlations during 7-day spontaneous fermentation of asparagus by-products. Dominant organic acids (lactic acid and acetic acid) and free amino acids (Ser, Glu, and Ala) increased with fermentation time, with lactic acid reaching 7.73 ± 0.05 mg/mL and Ser increasing 56-fold after 7 days. A total of 58 volatile flavor compounds were identified using headspace solid-phase microextraction-gas chromatography–mass spectrometry (HS-SPEM/GC–MS), with esters, alcohols and acids as the main volatile flavor compounds. Fourteen volatile flavor compounds had odor activity value >1. High-throughput sequencing showed Firmicutes and Proteobacteria as the main bacterial phyla, dominated by lactic acid bacteria (Levilactobacillus, Lactiplantibacillus, Weissella). Correlation analysis revealed that five bacterial genera (Levilactobacillus, Lactiplantibacillus, Enterobacter, Pediococcus and Acetobacter) were highly correlated with organic acids, free amino acids, and volatile flavor compounds, indicating their pivotal role in forming the characteristic flavor of fermented asparagus by-products (FAPS). This study provides new insights into the flavor and microbial profile of FAPS, offering a strategy for value-added processing and industrial production.

Effects of industrial-scale pickling processes on the dynamic changes in the physicochemical indicators and microbial diversities of Yacai

The effects of dry-salted and salt-fermented processing on the physicochemical characteristics and microbial communities of Yacai were systematically investigated. The results showed that the contents of total acid, amino acid nitrogen (AAN) and nitrite in the final products of dry-salted Yacai were greater than those in salt-fermented Yacai. Lactic acid was the dominant organic acid in the two types of Yacai. Dry-salted processing is more conducive to forming a high-quality reddish-brown color. During whole pickling process, the microbial diversity of dry-salted Yacai was higher than that of salt-fermented Yacai, particularly in the early and middle stages of fermentation. For dry-salted Yacai, 8 bacteria (Natribacillus, Chromohalobacter, Marinococcus, Lentibacillus, Nesterenkonia, Gracilibacillus, Oceanobacillus and Tetragenococcus) and 1 fungus (Zygosaccharomyces) showed a significant positive correlation with AAN. For salt-fermented Yacai, 8 bacteria (Gracilibacillus, Alkalibacillus, Oceanobacillus, Virgibacillus, Lentibacillus, Salibacterium, Chromohalobacter and Tetragenococcus) and 3 fungi (Zygosaccharomyces, Millerozyma, and Wickerhamomyces) exhibited significant positive correlations with AAN.

Effect of Lactobacillus rhamnosus and Saccharomyces cerevisiae on the flavour profile of sweet fermented glutinous rice (Jiu Niang)

SummaryRecently, there has been growing interest in intentionally incorporating fermentation starters into the traditional brewing process. Our study examined the impact of Saccharomyces cerevisiae and Lactobacillus rhamnosus on the flavour profiles of sweet fermented glutinous rice (SFGR). Saccharomyces cerevisiae obviously increased the ethanol content, whereas Lactobacillus rhamnosus notably raised the total acidity. Lactic acid became the dominant organic acid after the addition of Lactobacillus rhamnosus. The volatiles were analysed using electronic nose (E‐nose) and gas chromatography‐ion mobility spectrometry (GC‐IMS). S4 sensor of E‐nose exhibited the most extensive response to all samples. Saccharomyces cerevisiae increased ethanol and 3‐methylbutan‐1‐ol levels, while Lactobacillus rhamnosus led to a significant increase in acetone. Principal component analysis effectively discriminated the aroma of SFGR with different starters. Additionally, a strong correlation was observed between the E‐nose and GC‐IMS results. Our study shows that Saccharomyces cerevisiae and Lactobacillus rhamnosus can enhance the flavour of fermented rice products.

Preharvest Salicylic Acid and Oxalic Acid Decrease Bioactive and Quality Loss in Blackberry (cv. Chester) Fruits during Cold Storage

In this study, we investigated the effects of preharvest oxalic acid (2.5 mM (OA1) and 5 mM (OA2)) and salicylic acid (0.5 mM (SA1) and 1 mM (SA2)) treatments on the storage and quality of blackberry cv. Chester. We applied salicylic acid and oxalic acid to the plants seven and fourteen days before harvest and recorded the physiological, physicochemical, and external appearance characteristics of the fruits during the cold storage period (nine days). The results showed that the treatments decreased ethylene production by 29.5% (SA1) at harvest and by 28.5% (SA2) at the end of the storage period. In addition, the respiration rate was reduced between 13.0% (OA2) and 28.0% (SA2) compared to the control. Although fruit weigh loss increased as storage extended, the highest losses were observed in control with 1.35%. Titratable acidity decreased from harvest (0.46%) to the end of storage (0.39%) in the control, whereas it ranged from 0.52% (SA1) to 0.62% (OA1) in the treatment groups. Malic acid and syringic acid were the dominant organic acid and phenolic, respectively, and although their content decreased continuously in the control group, no loss was observed in the treated groups after the sixth day. These effects were positively reflected in the external appearance of the fruits, total phenolic content, total flavonoid content, and properties related to antioxidant activity. As a result of the cumulative evaluation of all parameters, it can be suggested that Chester fruits can be stored for nine days in marketable quality with the SA2 applications. Among oxalic acid concentrations, 2.5 mM can be recommended for phytochemical accumulation at harvest and short‐term storage of three days.

Sensory Evaluation, Biochemical, Bioactive and Antioxidant Properties in Fruits of Wild Blackthorn (Prunus spinosa L.) Genotypes from Northeastern Türkiye

Wild edible fruits are an important source for agriculture worldwide suffering from genetic erosion due to a severe genetic diversity reduction and domestication hindrance. In Türkiye, underutilized Prunus spinosa fruits are increasingly being considered as genetic resources and are marginally used by small farmers constituting a real safety valve for the sustainability of the processing plum value chain. Fruits of those plum genotypes differ in their biometric, processing and functional quality attributes. In this study, fruits of eight wild grown blackthorn (Prunus spinosa) genotypes were sampled from the Ispir district of the Erzurum province and subjected to sensory, morphological, biochemical and antioxidant characterization. Aroma, taste and juiciness were used as the criteria for sensory analysis, and a trained panel of ten experts established and evaluated the sensory characteristics of the fruits of the blackthorn. Fruit weight, fruit skin and flesh color as L*, a* and b* values were the main morphological parameters. For biochemical and bioactive analysis, organic acids, SSC (Soluble Solid Content), vitamin C, total anthocyanins, total phenolic content and total antioxidant capacity were determined. Antioxidant capacity was determined by FRAP (ferric reducing antioxidant power) assay. The results indicated significant differences among genotypes for most of the traits. The fruit weight was found between 2.78–3.67 g. The skin L*, a* and b* values were 13.11–16.12, 2.56–3.85 and 2.01–3.44, respectively. The flesh L*, a* and b* values were in the ranges of 17.45–20.37, 4.88–6.73 and 4.12–5.66, respectively. The SSC content ranged from 18.66% to 21.07%. The total phenolic content (TPC), total anthocyanin content (TAC) and ferric reducing antioxidant power (FRAP) were between 372–504 mg GAE/100 g; 53–72 mg cy-3 g eq./100 g and 107–134 mmol Fe (II) eq./g, respectively. The dominant organic acid was malic acid for all genotypes and varied from 1.04 g/100 g to 1.52 g/100 g fresh weight base. The data showed that the analyzed blackthorns, particularly PS-5, PS-3 and PS-2 had bigger fruits indicate their suitability for fresh and dried consumption, PS-1 and PS-3 had higher juiciness, indicating their suitability for processing, and PS-4 and PS-6 had higher human health promoting compounds (higher total phenolic content and antioxidant capacity), making them suitable for future use as functional foods and as promising sources of natural antioxidants.

Analysis of element yield, bacterial community structure and the impact of carbon sources for bioleaching rare earth elements from high grade monazite

Rare earth element (REE) recovery from waste streams, mine tailings or recyclable components using bioleaching is gaining traction due to the shortage and security of REE supply as well as the environmental problems that occur from processing and refining. Four heterotrophic microbial species with known phosphate solubilizing capabilities were evaluated for their ability to leach REE from a high-grade monazite when provided with either galactose, fructose or maltose. Supplying fructose resulted in the greatest amount of REE leached from the ore due to the largest amount of organic acid produced. Gluconic acid was the dominant organic acid identified produced by the cultures, followed by acetic acid. The monazite proved difficult to leach with the different carbon sources, with preferential release of Ce over La, Nd and Pr.

Changes on physiochemical properties and volatile compounds of Chinese kombucha during fermentation

Kombucha is a traditional fermented beverage in China. In this study, six samples of kombucha from different regions of China were fermented, and the pH, total acidity, organic acid, carbohydrate and volatile flavor compounds at different fermentation time were determined. The results showed that the acidity of the samples increased as fermentation progressed, which was manifested as a decrease in pH and an increase in total acidity. During the fermentation period, the content of all organic acids showed an upward trend, and acetic acid was the most dominant organic acid in kombucha. The content of sucrose showed a downward trend, but remained stable in the middle and late stages. However, the contents of glucose and fructose were increasing throughout the fermentation. Twenty volatile compounds were identified by headspace solid-phase microextraction with gas chromatography-mass spectrometry (HS-SPME-GC-MS), among which the contents of 2-phenylethanol, 2,5-dimethylbenzaldehyde, acetic acid, ethyl acetate, ethyl hexanoate, ethyl 2-phenylacetate, and 2-phenylethyl acetate were greatly increased, and could be used as markers of the flavor quality of kombucha. Principal component analysis and correlation analysis showed that unique quality characteristics of kombucha were formed during the fermentation, and fructose and glucose were related to the production of tartaric acid, malic acid, acetic acid, and other volatile compounds. This study provides a theoretical reference for the quality evaluation of kombucha, and is expected to help in developing kombucha products with high quality.

Investigation of microbial succession and volatile compounds dynamics during the fermentation of traditional cereal vinegar in Xinjiang

Cereal vinegar, a traditional acidic condiment in China. The quality of cereal vinegars varies depending on the raw materials used to produce them, fermentation methods and brewing environments. To investigate the microbial community succession and metabolite changes on the whole fermentation process of traditional cereal vinegar in Xinjiang, we analyzed it by high-throughput sequencing, high-performance liquid chromatography and head space solid phase micro-extraction-gas chromatography-mass spectrometry technology. The acetic acid (5733.33 mg/100 g), lactic acid (1265.33 mg/100 g) and succinic acid (520.00 mg/100 g), gallic acid (63.09 μg/g) and vanillic acid (29.05 μg/g) were the dominant organic acids and phenolic compounds in traditional cereal vinegar of Xinjiang, respectively. In later stage of aging, high levels of acetoin, ethyl phenylacetate, phenylethyl alcohol and ethyl lactate endowed the cereal vinegar with rosy, fruity and creamy aroma. The functional fungal genera were Saccharomyces, Fusarium and Kazachstania, and the functional bacterial were Pseudomonas, Lactobacillus, Acetobacter, Rhodococcus and Methylobacterium. Spearman's correlation coefficient showed that bacterial community had a strong correlation with various flavor compounds. The results could provide a theoretical reference for flavor enhancement and process improvement of traditional cereal vinegar in Xinjiang.

Field-scale differences in rhizosphere micro-characteristics of Cichorium intybus, Ixeris polycephala, sunflower, and Sedum alfredii in the phytoremediation of Cd-contaminated soil

Understanding the intricate interplay between Cd accumulation in plants and their rhizosphere micro-characteristics is important for the selection of plant species with profitable Cd phytoextraction and soil remediation efficiencies. This study investigated the differences in rhizosphere micro-ecological characteristics and Cd accumulation in chicory, Ixeris polycephala, sunflower, and Sedum alfredii in low-moderate Cd-contaminated soil. Data reveal that the dominant organic acids in rhizosphere soil that responded to Cd were oxalic and lactic acids in chicory and Ixeris polycephala, tartaric acid in sunflower, and succinic acid in Sedum alfredii. These unique organic acids could also influence the abundance of specific rhizobacterial communities in rhizosphere soil that were Sphingomonadaceae and Bradyrhizobiaceae in both Sedum alfredii (9.75 % and 2.56 %, respectively) and chicory (8.98 % and 2.82 %, respectively) rhizosphere soil, Xanthomonadaceae in both Sedum alfredii and Ixeris polycephala rhizosphere soil, and Gaiellaceae in chicory rhizosphere soil. In this case, the combined effects of the organic acids and unique rhizobacterial communities by plant species increased the bioavailable concentration of Cd in Sedum alfredii, Ixeris polycephala, and sunflower rhizosphere soil, while decreasing the Cd-DOM concentrations in chicory rhizosphere soil and the water-extractable Cd reduced by 88.02 % compared to the control. Though the capacity for Cd accumulation in the shoots of chicory was weaker than of Sedum alfredii but better than either Ixeris polycephala or sunflower, chicory presented better Cd translocation and harbored Cd mainly as the low toxic chemical form of pectates and proteins-bound Cd and Cd oxalate in its shoot. Generally, chicory, as an economic plant, is suitable for phytoremediation of low-moderate Cd-contaminated soil after Sedum alfredii.

Comparison of flavor profiles of Cantonese soy sauces obtained at different fermentation stages

In this study, we analyzed the differences, including organic acid, free amino acid, and volatile compound contents, in soy sauces obtained at different fermentation stages (stage A, Touyou; stage B, Eryou; stage C, Sanyou). The result showed that the content of total organic acids in Eryou (400.41 mg/kg) and Sanyou (393.95 mg/kg) was significantly higher than that in Touyou (376.52 mk/kg), even though lactic acid content showed no significant differences, which was the dominant organic acid among the three soy sauces. However, the total free amino acid content of Touyou (7.73 g/kg) was significantly higher than that of Eryou (5.82 g/kg) and Sanyou (6.44 g/kg). Moreover, the umami and bitter free amino acid contents in Touyou were significantly higher than those in Eryou (p < 0.50). Besides, Touyou and Sanyou showed the highest peak intensities of alcohols (130157.08) and acids (77943.05), respectively. PLS-DA showed that the soy sauces from different fermentation stages were well separated from each other based on the volatile compounds, and 19 volatile components were selected characteristic volatile compounds with VIP > 1. Thus, these differences in organic acid, free amino acid and volatile compound contents resulted in the variability in flavor and quality of Cantonese soy sauces at different fermentation stages.

PEP4-Allele Modification Provides an Industrial Brewing Yeast with Malate Stress Tolerance

Acid stress is a challenging condition that yeast cells must overcome during fermentation. Enhancing the inherent tolerance of industrial Saccharomyces cerevisiae to organic acid stresses is crucial for increasing fermentation efficiency and reducing economic costs. In a previous study, we constructed a Saccharomyces cerevisiae strain SWY85S with improved tolerance to citric acid stress by modifying the second PEP4-allele. Malic acid is a dominant organic acid in grapefruit, which forms the acidic constituents of wine fermentation mash and finished products. We investigated the malic acid stress tolerance of the strain SWY85S in comparison with that of a strain with one PEP4-allele disrupted and the wild-type strain in this study. Our results revealed that the strain SWY85S demonstrated greater tolerance of malic acid stress, regardless of whether it was cultured with adequate nutrient supplies or under amino acid starvation. Moreover, the strain SWY85S performed remarkably in converting glucose to ethanol during fermentation under malic acid stress. This study provides insights into the role of a vacuolar PEP4-allele coding product in response to environmental stress and the physiological mechanism of yeast to withstand organic acid stress.

Colonization Mechanism of Endophytic Enterobacter cloacae TMX-6 on Rice Seedlings Mediated by Organic Acids Exudated from Roots

Small molecular organic acids (SMOAs) in root exudates are critical for plant-microbe interaction, especially under environmental stresses. However, the dominant organic acids driving the process and promoting the colonization are unclear. Here, using a target metabolomics, 20 main SMOAs of rice root exudates were identified and analyzed in control and 10 mg/L thiamethoxam-treated groups. The composition of these SMOAs differed significantly between the two treatments. Among which, malic acid, citric acid, succinic acid, and proline induced a chemotactic response, swimming ability, and biofilm formation of Enterobacter cloacae TMX-6 in a dose-dependent manner. The maximal chemotactic response of TMX-6 was induced by proline at 10 mg/L, and a strong chemotactic response was even observed at 0.01 mg/L. The recruitment assay confirmed that the addition of these four compounds promoted the colonization of TMX-6. The results provide insight for directional regulation of plant-microbe interactions for beneficial outcomes.

Physiochemical Changes of European Pear cv. Conference and Asian Pear cv. Yali during Cold Storage

This study evaluated the physiochemical changes of one commercial European pear variety ‘Conference’ and one Asian pear variety ‘Yali’ during 60 days of storage at 1 °C. Content of organic acids, ethylene and formation of CO2 were determined using HPLC/UV-VIS and GC/FID and TCD detectors, respectively. This study presents an evaluation of the influence of the above-mentioned factors and long-term storage on quality parameters, including the antioxidant capacity of an important European and Asian pear cultivar. There was a significant effect of temperature on respiration rate in both varieties. Development of the respiration intensity had a similar course in European and Asian pears. The high values of CO2 production at the beginning of storage for the variety ‘Conference’ (14.08 mg·kg−1·h−1) and ‘Yali’ (23.37 mg·kg−1·h−1) were followed by a sharp decline of 80% and 83% at later stages of storage at 1 °C, respectively. Ethylene formation in fruit increased with storage time and was the highest after 60 days in cold storage, especially in ‘Yali’ (7.14 µL·kg−1·h−1). The results show the relation between ethylene formation and ripening-related fruit parameters. The ‘Yali’ variety showed negligible changes in soluble solids content and flesh firmness during storage ranging from 0.35 to 0.60 MPa. The most represented sugar determined enzymatically was fructose and malic acid was the dominant organic acid in pear fruit. Antioxidant activity determined using the FRAP and DPPH methods did not change significantly during 60 days of storage.

A New Substrate and Nitrogen Source for Traditional Kombucha Beverage: Stevia rebaudiana Leaves.

Recently, the use of different herbal products as carbon sources instead of black and green tea in the preparation of traditional kombucha has been investigated. In this study, functional kombucha was prepared by adding Stevia rebaudiana Bertoni leaves, which have special organoleptic properties, to kombucha medium, and some properties of the beverage were analyzed. Tea blends were determined as 100% green tea (control = C), 75% green tea (GT) + 25% Stevia (ST), 50% GT + 50% ST, and 100% ST. On the 15th day of fermentation, gluconic acid (43.12 ± 0.01 g/L) was detected as dominant organic acid in GT75 + ST25 samples compared to group C (p < 0.05). According to physicochemical parameters that determine the drinkability properties of prepared teas, the best results were in GT25 + ST75 compared to group C (p < 0.05). It proved that the highest activity was in GT25 + ST75 on the 10th day in the groups that applied different antioxidant tests (DPPH, MCA, and CUPRAC). The antimicrobial activities of kombucha at 25, 50, 75, and 100% concentrations of GT and ST reached the highest levels in the GT25 + ST75 group in samples after 10 days of fermentation for all selected microorganisms. The results prove that GT25 + ST75 kombucha is a functional product with high drinkability on the 10th day of fermentation and also more beneficial for health due to the phenolic compounds from both green tea and Stevia. Stevia rebaudiana leaves can be suggested that be used as a new substrate and nitrogen source for kombucha production.

Split batch and coculture fermentation to regulate the organic acids and flavor profile of fruit wine-a case study of Prunus mume Sieb. et Zucc (greengage) wine

The higher acidity in fruits compared with grapes was one of the main obstacles to producing high-quality fruit wines. In the present research, the effect of the split batch fermentation pattern on the metabolites of greengage wines was investigated. This fermentation pattern included whole fruit immersion in the sucrose and coculturing Saccharomyces bayanus Y4 with Torulaspora delbrueckii Y7. These results showed that the contents of total acidity and dominant organic acids were significantly reduced among the batches. Aliphatic compounds were decreased with the batches, while aromatic compounds that contributed to flavor improvement were increased oppositely. The acetate esters, ketones, and terpenes contents were significantly increased in the first batch of coculture. In addition, acidic stress largely affected the kinetics characteristics of greengage wine on a pilot scale. Interestingly, the increment of total acidity was closely associated with the rate of total sugar consumption, which was affected by microbial activities. The acidity content was significantly declined and distinct flavour profiles were formed in split batch and coculture fermentation of greengage wines. It provides a new avenue to enhance the flavor and quality of fruit wines.

Effect of postharvest spermidine treatments on quality and biochemical properties of nectarine fruits

In this study, the effect of spermidine (SP) treatments at different doses after harvest on the changes in the pomological and biochemical contents of nectarine fruits was determined. The fruits were placed in cold storage (4 ± 0.5 °C and 90 ± 5% RH) for 30 days. Specific organic acids and phenolic compounds from biochemical compounds were analyzed by HPLC device. Weight loss and decay values, which are quality criteria of nectarine fruits, increased during storage compared to the harvest period. In this study, 1.0 mM SP application was found to be more successful in the preservation of visual quality (fruit pulp firmness and weight loss) properties during storage. At the end of the storage period (30th day), weight loss was determined as 3.27% in the control group and 1.84% in the 1.5 mM SP treatment. Fruit flesh firmness value, which is one of the important quality parameters affecting the storage life of fruits, was determined as 30.97 N in the control group and 37.06 N in 1.5 mM SP doze (30th day). Contrary to the acidity values, the total soluble solids content (TSS) and fruit juice pH values increased during storage. In this research, when the organic acid and phenolic compound contents are examined; it was determined that the dominant organic acid and phenolic compound in nectarine fruits were malic acid and chlorogenic acid, respectively. The malic acid ratio was found to be 4.89 g/kg in the control group and 6.66 g/kg in 1.5 mM SP treatment at the end of the 30-day storage period. Chlorogenic acid content was recorded as 6.86 mg/100g in the control group and 8.82 mg/100g in 1.5 mM SP application at the end of the storage period (30th day). In this study, it was determined that a 1.5 mM SP dose after harvest was effective on the biochemical contents of nectarine fruits and protected the fruits more during storage.

Chemical and Sensory Characteristics of Different Red Grapes Grown in Xinjiang, China: Insights into Wines Composition

Globally, the red wine market experienced a rapid growth in the last decade, due to the superior colour, taste, and nutritional quality. The red grapes used for vinification have individual characteristics varying within the regional environment. In this study, the quality of seven grape cultivars, including Marselan, Yan 73, Muscat Hamburg, Kadarka, Merlot, Cabernet Sauvignon, and Crimpose, and their corresponding wines, were investigated based on high-performance liquid chromatography and headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry. These techniques were performed to analyze the chemical compositions and volatile compounds of the tested samples, respectively. The results showed that tartaric acid (29.96% to 73.45%) and rutin (12.53% to 56.54%) were the dominant organic acid and phenolic compounds in grapes, respectively. Higher concentrations of organic acids and phenolic compounds, and the types of volatile compounds, were observed to be highest in the Cabernet Sauvignon grape. The antioxidant activity of wines ranged from 6.74 to 102.68 mmol TE/L, and Yan 73 wine had the highest antioxidant activity. A total of 69 volatile compounds consisting of 17 alcohols, 26 esters, 5 aldehydes, 9 acids, 7 ketones, and 5 other volatile compounds were identified in all tested wines, and 11 important aroma active substances (odor activity value &gt; 1) were selected, consisting of β-ionone, phenethyl acetate, geranyl acetate, ethyl 9-decenoate, ethyl caprate, ethyl pelargonate, decanal, ethyl caprylate, 6-methyl-5-hepten-2-one, methyl 2-hexenoate, and ethyl hexanoate, which endow wines with a unique aroma. This work clearly describes the chemical and sensory characteristics of seven red grape cultivars in Xinjiang of China and provides diversity options for cultivars for winemaking.

Comparison of traditional Zivzik pomegranate vinegar against commercial pomegranate vinegar: antioxidant activity and chemical composition

The vinegar, which is known to be very beneficial for health, also changes its usage potential and chemical properties according to the raw material it is obtained from. In this study, Zivzik pomegranate Vinegar produced with the traditional methods from Zivzik pomegranate varieties was compared with commercial pomegranate vinegar in terms of physicochemical properties, total phenolic, total flavonoid, and total anthocyanin content, organic acid, sugar, and phenolic acid composition by HPLC, elemental analysis by ICP-OES and antioxidant properties. As a result of the study, Zivzik pomegranate vinegar was found to be more antioxidant than commercial vinegar. In both vinegar samples, K is the dominant element. Similarly, acetic acid is the dominant organic acid detected in both types of vinegar. While chlorogenic acid was the dominant phenolic compound in commercial pomegranate vinegar, it was determined that gallic acid was dominant in Zivzik pomegranate vinegar. As a result, while it was determined that the origin and variety of the raw material had a direct effect on the product quality obtained, it was concluded that the vinegar obtained by traditional methods was more beneficial in terms of health than commercial vinegar.