Fructose Research Articles

Transcriptome and Metabolome Combined Analysis Reveals Key Genes Controlling Soluble Sugar Metabolism in Persimmon Fruit During Development

Persimmon as a type of fruit is divided into pollination-constant and non-astringent (PCNA) persimmon, which can lose its astringency naturally during fruit ripening, and non-PCNA persimmon. Its soluble sugars include the essential components that determine the flavor of the persimmon fruit. However, the underlying regulatory networks that modulate the metabolism of soluble sugar in persimmon fruit remain largely unknown. In this work, three stages (10, 15, and 20 weeks after bloom) of Chinese PCNA ‘Luotian tianshi’ fruit growth were used as experimental models to reveal the molecular mechanism of soluble sugar metabolism via the combination of the transcriptome and the metabolome. Here, 21 kinds of soluble sugars were detected, with sucrose, glucose, and fructose verified as the main soluble sugars in the persimmon fruits. We obtained 59.42 Gb of clean data via transcriptome sequencing, and the maximum number of differentially expressed genes (9098) was found in the 20 W vs. 10 W groups, of which 2513 were up-regulated and 3811 were down-regulated. The KEGG enrichment analysis showed that 37 up-regulated and 71 down-regulated differentially expressed genes were enriched for starch and sucrose metabolism in the 20 W vs. 10 W groups. The metabolome and transcriptome association analysis showed that the differentially expressed genes (malZ, INV, SPS, scrK, ISA, β-AMY, TPS, otsB, and TREH) were significantly correlated with the content of differentially accumulated metabolites (such as sucrose, glucose, and fructose), indicating that they may play important roles in the metabolism of the soluble sugars in persimmon. Overall, this study provides valuable insights into the metabolism pattern of high sugar accumulation in persimmon fruit.

A Comprehensive Review on Cucurbit Grafting: A Sustainable Approach to Boost Crop Performance

Grafting, which unites the rootstock and scion of a plant, is crucial for combating soil-borne diseases in cucurbitaceous crops such as watermelon, melon, bitter gourd, summer squash and cucumber. Essential due to limited arable land and off-season demand, this technique enhances plant vigour by improving nutrient uptake and providing resistance to soil pathogens, salinity, drought and temperature variations, thereby improving overall yield and fruit quality. Initially implemented in Japan in the late 1990s, grafting significantly affects fruit pH, flavour, sugar content, carotenoids, and texture. Globally, it has been adopted to prevent diseases like fusarium wilt and root-knot nematode. This practice mitigates production losses under adverse conditions and promotes organic, safer vegetables by reducing pesticide residues. Recent advancements in grafting methods and versatile rootstocks further support its widespread use.

Unraveling the genetic architecture of blueberry fruit quality traits: major loci control organic acid content while more complex genetic mechanisms control texture and sugar content

BackgroundFruit quality traits, including taste, flavor, texture, and shelf-life, have emerged as important breeding priorities in blueberry (Vaccinium corymbosum). Organic acids and sugars play crucial roles in the perception of blueberry taste/flavor, where low and high consumer liking are correlated with high organic acids and high sugars, respectively. Blueberry texture and appearance are also critical for shelf-life quality and consumers’ willingness-to-pay. As the genetic mechanisms that determine these fruit quality traits remain largely unknown, in this study, an F1 mapping population was used to perform quantitative trait loci (QTL) mapping for pH, titratable acidity (TA), organic acids, total soluble solids (TSS), sugars, fruit size, and texture at harvest and/or post-storage and weight loss.ResultsTwenty-eight QTLs were detected for acidity-related parameters (pH, TA, and organic acid content). Six QTLs for pH, TA, and citric acid, two for quinic acid, and two for shikimic acid with major effects were consistently detected across two years on the same genomic regions on chromosomes 3, 4, and 5, respectively. Putative candidate genes for these QTLs were also identified using comparative transcriptomic analysis. No QTL was detected for malic acid content, TSS, or individual sugar content. A total of 146 QTLs with minor effects were identified for texture- and size-related parameters. With a few exceptions, these QTLs were generally inconsistent over years and post-storage, indicating a highly quantitative nature.ConclusionsOur findings enhance the understanding of the genetic basis underlying fruit quality traits in blueberry and guide future work to exploit DNA-informed selection strategies in blueberry breeding programs. The major-effect QTLs identified for acidity-related fruit characteristics could be potential targets to develop DNA markers for marker-assisted selection (MAS). On the other hand, genomic selection may be a more suitable approach than MAS when targeting fruit texture, sugars, or size.

Strawberry plant growth enhancement: Effects of artificial light and methyl jasmonate-salicylic acid treatments on physiology and metabolism.

Strawberries, known for their antioxidant properties, exhibit changes in physiology and metabolite profiles based on cultivation techniques. In Indonesia, strawberries are typically grown in highland regions, but climate change has necessitated adjustments in cultivation practices to enhance production and quality. This study investigates the adaptation of strawberry plants in lowland environments using light-emitting diodes (LEDs) and the exogenous application of methyl jasmonate (MeJA) and methyl salicylic acid (MeSA). A randomized block design was used with two factors: LED light types and MeJA-MeSA treatments. While the treatments did not significantly affect shoot growth (initially 1.5-2cm, increasing 3-5 times by day 3), chlorophyll content, or fruit sugar levels, notable effects were observed in leaf glucose accumulation. The control group showed a fivefold increase (0.55μgml-1), while LED-hormone treatments resulted in a 27-64% lower increase (0.20-0.40μgml-1). Fructose levels followed a similar pattern, and malic acid content was highest in the MeJA treatment (5.76mgml-1), with MeSA treatments also enhancing malic acid (5.91mgml-1). The secondary metabolite analysis, conducted using GC-MS and LC-MS, identified key defense-related compounds, including terpenoids, saturated fats, alkaloids, and amino acid derivatives, which play a role in the plant's defense mechanisms. These findings highlight the potential of LED lighting and hormone applications to modulate strawberry physiology and suggest further research into their role in plant stress responses.

Mechanism of induced soluble sugar accumulation and organic acid reduction in plum fruits by application of melatonin

Melatonin (MT) can improve plant resistance and fruit quality. The mechanism by which MT affects soluble sugar and organic acids accumulation in drupe fruits is not clear. In this study, 100 µmol/L MT was sprayed on the leaves of plum trees at the second stage of rapid fruit expansion (90 and 97 d after flowering), and the effects of MT on plum fruit quality and its effects on the soluble sugar-organic acid metabolism were investigated. At 28 d after MT treatment (at maturity), the longitudinal diameter, fruit weight, and vitamin C content of plum fruits were increased by 5.05%, 12.93%, and 56.09%, respectively, compared to the control. MT caused significant increase in the total soluble solids content and decreased the titratable acid content. MT increased the contents of total soluble sugar, sucrose, sorbitol, and citric acid after 21 and 28 days of treatment, while decreasing the contents of fructose, malic acid, quinic acid, and tartaric acid after 28 days of treatment. Additionally, MT increased the activities of sucrose synthase (catabolism direction), sucrose phosphate synthase, glucokinase, fructokinase, sorbitol oxidase, and NADP+-malic enzyme, and decreased the activities of soluble acid converting enzyme, cell wall insoluble converting enzyme, NAD+-sorbitol dehydrogenase, and NAD+-malic dehydrogenase after 21 or 28 days of treatment. Moreover, the differentially expressed genes (DEGs) after 21 and 28 days of treatment were accelerated starch and sucrose metabolism, galactose metabolism, fructose and mannose metabolism, as well as glycolysis, gluconeogenesis, and pentose phosphate metabolism pathways. In conclusion, exogenous MT increases soluble sugar content and decreases organic acid content in plum fruits by regulating various soluble sugar-organic acid metabolic pathways, thereby improving the fruit quality.

The hexose transporters CsHT3 and CsHT16 regulate postphloem transport and fruit development in cucumber.

Hexoses are essential for plant growth and fruit development. However, the precise roles of hexose/H+ symporters in postphloem sugar transport and cellular sugar homeostasis in rapidly growing fruits remain elusive. To elucidate the functions of hexose/H+ symporters in cucumber (Cucumis sativus L.) fruits, we conducted comprehensive analyses of their tissue-specific expression, localization, transport characteristics, and physiological functions. Our results demonstrate that CsHT3 (C. sativus hexose transporter), CsHT12, and CsHT16 are the primary hexose/H+ symporters expressed in cucumber fruits. CsHT3 and CsHT16 are localized in the sieve element-companion cell during the ovary and early fruit development stages. As the fruit develops and expands, the expression of both symporters shifts to phloem parenchyma cells. The CsHT16 knockout mutant produces shorter fruits with a larger circumference, likely due to impaired sugar and phytohormone homeostasis. Concurrent reduction of CsHT3, CsHT12, and CsHT16 expression leads to decreased fruit size. Conversely, CsHT3 overexpression results in increased fruit size and higher fruit sugar levels. These findings suggest that CsHT16 plays an important role in maintaining sugar homeostasis, which shapes the fruit, while CsHT3, CsHT12, and CsHT16 collectively regulate the supply of carbohydrates required for cucumber fruit enlargement.

Prediction of NPK doses based on targeted fruit sugar content in Cucumis melo L. ‘Cantaloupe’ using a simple regression method

The fruit sweetness is the main target in melon plant production. The highest criterion of sweetness is excellent, with 16% of total sugar content. Modification of essential plant nutrients is the alternative to reach that category. So, this study aims to obtain optimum NPK doses using a simple regression method. The experiment was conducted in a greenhouse with a soilless culture hydroponic system from August until November 2023 using a completely randomized design (CRD) with five treatments and four replications. The parameters included leaf area, plant dry matter, leaf nutrient uptake, fruit weight, and fruit sugar content. Pearson correlation analysis showed that the total sugar content in fruit has a significantly positive correlation with potassium in NPK fertilizer treatments such as K2O dose and K2O uptake at 7 WAP, i.e., 0.932 and 0.973, respectively. According to the regression model y = -50.7 + 1.079 N + 0.251 P2O5 + 0.528 K2O, the NPK formula fertilizer containing 31.56 g N, 23.99 g P2O5, and 50.42 g K2O can be used by grower to produce excellent fruit sugar content.

CBL1/CIPK23 phosphorylates tonoplast sugar transporter TST2 to enhance sugar accumulation in sweet orange (Citrus sinensis).

Fruit taste quality is greatly influenced by the content of soluble sugars, which are predominantly stored in the vacuolar lumen. However, the accumulation and regulation mechanisms of sugars in most fruits remain unclear. Recently, we established the citrus fruit vacuole proteome and discovered the major transporters localized in the vacuole membrane. Here, we demonstrated that the expression of tonoplast sugar transporter 2 (CsTST2) is closely associated with sugar accumulation during sweet orange (Citrus sinensis) ripening. It was further demonstrated that CsTST2 had the function of transporting hexose and sucrose into the vacuole. Overexpression of CsTST2 resulted in an elevation of sugar content in citrus juice sac, calli, and tomato fruit, whereas the downregulation of its expression led to the reduction in sugar levels. CsTST2 was identified as interacting with CsCIPK23, which binds to the upstream calcium signal sensor protein CsCBL1. The phosphorylation of the three serine residues (Ser277, Ser337, and Ser354) in the loop region of CsTST2 by CsCIPK23 is crucial for maintaining the sugar transport activity of CsTST2. Additionally, the expression of CsCIPK23 is positively correlated with sugar content. Genetic evidence further confirmed that calcium and CsCIPK23-mediated increase in sugar accumulation depends on CsTST2 and its phosphorylation level. These findings not only unveil the functional mechanism of CsTST2 in sugar accumulation, but also explore a vital calcium signal regulation module of CsCBL1/CIPK23 for citrus sweetness quality.

Перспективные сорта и гибридные формы абрикоса селекции Дагестанской селекционной опытной станции плодовых культур

Abstract. The article presents the results of a comprehensive assessment of breeding varieties and hybrid forms of apricot (Prunus armeniaca L.) for 2021-2023 based on the following traits: yield capacity, resistance to major diseases (clasteresporium and moniliosis), and fruit quality. The following varieties were distinguished by yield capacity: Tamasha (8.0 t/ha), Uzden (8.9 t/ha), Kokan kyurek (7.3 t/ha) (early ripening); Hukumat kyurek (10.2 t/ha) and hybrid 3/34 (9.2 t/ha) (mid-season ripening) and Esdelik (10.4 t/ha), Untsukulskiy late (10.6 t/ha), Dzhengutaevskiy (9.7 t/ha) (late ripening). Among the studied breeding varieties and hybrid forms, Tamasha (0.5 points) and Uzden (0.1 points) are noted for their comparatively high resistance to clasterosporium. For the other varieties and hybrid forms, this indicator is in the range from 1.0 points to 1.7 points. In terms of resistance to blossom blight, Tamasha and Uzden (0.5 points) stand out among the early varieties; among the mid-season ripening varieties, the seedling Khonobakha (0.5 points) and among the late varieties, Dzhengutaevskiy and Untsukulskiy pozdniy (0.5 points). Damage by fruit rot in most varieties and hybrid forms fluctuates between 0.1 and 0.5 points. Only three varieties have this indicator in the range from 0.8 to 1.0 points. The content of total sugar in fruits of breeding varieties and hybrid forms of apricot varied from 5.8 to 9.8%. The varieties with large fruit size (fruit weight over 35 g) Bukhara, Esdelik, Uzden, Salikh, Musa, Dzhengudaevskiy and hybrids 3/34 and 6/22 have been selected. The selected breeding varieties and hybrid forms of apricot will be recommended for inclusion in targeted crossings in order to increase the efficiency of the breeding process. Keywords: breeding variety, hybrid form, adaptability, clusteresporium, moniliosis, fruit rot, yield capacity

Exogenous GABA improves tomato fruit quality by contributing to regulation of the metabolism of amino acids, organic acids and sugars

To better explore the impact of exogenous GABA on tomato fruit quality, we explored the effects of GABA (20 mM) on tomato fruits at different developmental stages. The results showed that spraying GABA 3 days before harvest improved the quality of fruits, primarily in terms of amino acid, organic acid, and soluble sugar content. Transcriptome and metabolome data indicated that exogenous GABA enters cells and mitochondria through GABA transporters, thereby simulating endogenous GABA metabolism and enhancing the activity of genes related to amino acids and organic acids metabolism, and elevating the levels of amino acids and organic acids. Moreover, the application of exogenous GABA promoted the contents of glucose, fructose, and sucrose by affecting the expression of genes related to sugar metabolism. It was found that the mechanism of exogenous GABA in increasing fruit sugar content involved promoting sucrose synthesis, partially inhibiting glycolysis, and increasing the content of trehalose 6-phosphate. This study also provides a new model for the mechanism through which exogenous GABA affects tomato quality.

Gene expression and soluble sugar accumulation in perennial fruits

Abstract Soluble sugars primarily contribute to fruit flavouring and are crucial for fruit quality. Carbohydrate accumulation in fruits is a multifaceted process that can be influenced by their biosynthesis capacity, sink strength, homeostasis, and vacuolar storage ability. Moreover, total soluble sugar contents in fruits also vary among different varieties/species and environmental conditions. Numerous studies have elucidated the carbohydrate regulatory mechanism in fruits; however, there is a knowledge gap regarding the most important contributor to soluble sugar accumulation in perennial fruits. Here, we briefly discussed the recent advances, including carbohydrate long-distance transportation, metabolism and vacuolar storage, and transcript factors for soluble sugar accumulation in fruits. Most importantly, we elucidated that the sink strength in fruit is the most crucial factor that can trap more soluble sugars by maintaining continuous unloading to fruit by genes of cell wall invertase; moreover, genes of sucrose transporters/pyrophosphatase play key roles in vacuolar storage of soluble sugars in perennial fruits. This review delivers a comprehensive summary of recent findings for soluble sugar regulation and fruit quality improvement, which may facilitate sugar optimisation in fruit crops for enhanced fruit quality.

Releasing a sugar brake generates sweeter tomato without yield penalty

In tomato, sugar content is highly correlated with consumer preferences, with most consumers preferring sweeter fruit1–4. However, the sugar content of commercial varieties is generally low, as it is inversely correlated with fruit size, and growers prioritize yield over flavour quality5–7. Here we identified two genes, tomato (Solanum lycopersicum) calcium-dependent protein kinase 27 (SlCDPK27; also known as SlCPK27) and its paralogue SlCDPK26, that control fruit sugar content. They act as sugar brakes by phosphorylating a sucrose synthase, which promotes degradation of the sucrose synthase. Gene-edited SlCDPK27 and SlCDPK26 knockouts increased glucose and fructose contents by up to 30%, enhancing perceived sweetness without fruit weight or yield penalty. Although there are fewer, lighter seeds in the mutants, they exhibit normal germination. Together, these findings provide insight into the regulatory mechanisms controlling fruit sugar accumulation in tomato and offer opportunities to increase sugar content in large-fruited cultivars without sacrificing size and yield.

Recent Advancements in Harnessing Lactic Acid Bacterial Metabolites for Fruits and Vegetables Preservation.

Postharvest losses in fruits and vegetables exert substantial economic and environmental repercussions. Chemical interventions are being widely utilized for the past six decades which may lead to significant health complications. Bioprotection of fruits and vegetables is the need of the hour in which use of lactic acid bacteria (LAB) with GRAS status predominantly stands out. Incorporation of LAB in postharvest fruits and vegetables suppresses the growth of spoilage organisms by synthesizing various antimicrobial compounds such as bacteriocins, organic acids, hydrogen peroxide (H2O2), exopolysaccharides (EPS), and BLIS. For example, Pediococcus acidilactici, Lactobacillus plantarum, and Limosilactobacillus fermentum convert natural sugars in fruits and vegetables to lactic acid and create an acidic environment that do not favour spoilage organisms. LAB can improve the bioavailability of vitamins and minerals and enrich the phenolic profile and bioactivity components. LAB has remarkable physiological characteristics like resistance towards bacteriophage, proteolytic activity, and polysaccharide production which adds to the safety of foods. They modify the sensory properties and preserve the nutritional quality of fruits and vegetables. They can also perform therapeutic role in the intestinal tract as they tolerate low pH, high salt concentration. Thus application of LAB, whether independently or in conjunction with stabilizing agents as edible coatings, is regarded as an exceptionally promising methodology for ensuring safer consumption of fruits and vegetables. This review addresses the most recent research findings that harness the antagonistic property of lactic acid bacterial metabolites, formulations and coatings containing their bioactive compounds for extended shelf life of fruits and vegetables.

Genetic and QTL analysis of sugars and acids content in sweet cherry (Prunus avium L.)

Abstract Sweet cherry is very appreciated by consumers because of its attractive appearance and taste, which is determined by the balanced sweet-sour flavor. In this work, the genetics of soluble solid content (SSC), titratable acidity (TA), sugars and organic acids was investigated in sweet cherry to facilitate breeding improvement for fruit quality. The fruits of five sweet cherry populations (N = 372), three F1 and two F2, were sampled over two years to evaluate SSC, TA, and the content of individual sugars (glucose, fructose, sorbitol, and sucrose) and organic acids (malic, quinic, oxalic, citric and shikimic) by ultra-performance liquid chromatography (UPLC). Glucose, followed by fructose, was the most abundant sugar, while malic acid was the predominant acid. Sorbitol and malic acid were the most stable compounds between years, and had the highest heritability, being also the best correlated to SSC and TA respectively, revealing their relevance for breeding. Significantly positive correlations were observed among sugars and SSC, and acids and TA, but high interannual variability between years was observed for all traits. QTL mapping for SSC, sugars, TA, and organic acids was performed using a multi-family approach with FlexQTL™. Twenty QTLs were detected consistently during the two phenotyped years, and several relevant regions with overlapping QTLs for sugars and acids were also identified. The results confirmed major stable SSC and TA QTLs on the linkage groups 4 and 6, respectively. Within the main LG4 SSC QTL region, where maturity and fruit development time QTLs have been previously detected, three stable sugar (glucose, sorbitol, and sucrose) and two acid (quinic, shikimic) QTLs were also identified, suggesting a pleiotropic effect of ripening date on the content of these compounds. The major malic acid QTL overlapped with TA QTL on LG6, thus TA QTL mapping in LG6 may correspond to malic acid QTLs. Haplotype analyses of major SSC and sugars QTL in LG4, and TA and malic acid in LG6 revealed haplotypes of breeding interest. Several candidate genes previously identified in other Prunus fruit species, like peach, were found to collocate with the QTLs detected herein. This work reports QTLs regions and haplotypes of sugar and acid content in a Prunus non-climacteric stone fruit for the first time.

High-Fructose Diet and Chronic Unpredictable Stress Modify Each Other's Neurobehavioral Effects in Female Rats.

A pervasive exposure to stressors and the consumption of fructose-containing beverages usually go hand-in-hand in everyday life. In contrast to their metabolic outcomes, their impact on the brain and behavior is still understudied. We examined the behavioral response to a novelty (open field test), the expression of biochemical indicators of neuronal activity (Egr1 and FosB/ΔFosB), the synaptic potentiation (CaMKIIα and pCaMKIIThr286), the synaptic plasticity (synaptophysin, PSD95, gephyrin, and drebrin), and the GABAergic system (parvalbumin and GAD67), along with the glucocorticoid receptor (GR) and AMPK, in the medial prefrontal cortex of female Wistar rats subjected to liquid fructose supplementation (F), chronic unpredictable stress (S), or both (SF) over 9 weeks. The only hallmark of the F group was an increased expression of pCaMKIIThr286, which was also observed in the S group, but not in the SF group. The SF group did not show hyperactivity, a decreased expression of FosB, or an increased expression of parvalbumin, as the S group did. The SF group, as with the S group, showed a decreased expression of the GR, although the basal level of corticosterone was unchanged. The SF group showed, as de novo marks, thigmotactic behavior, increased drebrin, and decreased gephyrin expression. These findings suggest that the long-term consumption of fructose, which itself has subtle neurobehavioral consequences, in combination with stress prevents some of its effects, but also contributes to novel outcomes not seen in single treatments.

Potential reformulation of food products two years after implementation of Nutri-Score in Belgium

Abstract Background Nutri-score is a front of pack labeling system that provides consumers with simplified information of the nutritional quality of food products. It is based on a five color (green to red) or letter (A to E) scheme that grades the quality of the product using an algorithm that takes into account the energy, sugar, saturated fats, salt, fiber, protein content, and percent of fruits and vegetables. In Belgium, Nutri-score was implemented on a voluntary basis in April 2019. This study aims to explore reformulation of products with Nutri-score by comparing their nutrient content and Nutri-score distribution in 2019 and 2021. Methods Product data from one of the major retailers was used in the analysis. Similar products in 2019 and 2021 with matched barcodes were used. Descriptive statistics were computed and statistical analyses such as the signed rank test and the McNemars test were performed to respectively evaluate the changes in the nutrient content and Nutri-score. The tests were conducted at 5% level of significance. Results From the matched sample of 668 products, about 55% had a Nutri-score of A and B in both 2019 and 2021. The proportion of food products with Nutri-Score of A/B and of D/E was not significantly different after two years of Nutri-Score implementation. Results showed a significant decrease in the median energy content of dairy, sauces, and meat products and in the median sugar content of dairy and fruit and vegetable products. There was a significant increase in the median fiber content of the dairy, meat products, and non-alcoholic beverages. For all food groups, the salt content of the products in 2019 and 2021 was not significantly different. Conclusions This two-year interval analysis described the changes in the classification and reformulation of the products with Nutri-score. Favorable changes in the nutrient quality of the product profiles reveals improvement in their reformulation. Key messages • In this analysis, changes has been observed in the nutrient content of food products between 2019 and 2021. • Producers or manufacturers should continue working on commitments to enhance the nutritional quality of the products delivered to consumers.

Effect of fruit pulp and sugar concentration on the physicochemical, phytochemical and sensory characteristics of star fruit (Averrhoa carambola) leather

Starfruit is an underutilized fruit and is rich in vitamin C. Fruit leather from starfruit was prepared in this study and analyses of its physicochemical, phytochemical, and sensory characteristics were performed. Five samples named A, B, C, D and E were prepared with different proportions of fruit pulp:sugar of 70:30, 75:25, 80:20, 85:15 and 90:10, respectively. All the prepared samples were subjected to analyses. Phytochemical contents were found to increase with increasing fruit pulp proportion, thus sample E (90:10) was found to be the best in terms of phytochemical content. Similarly, product sample C (80:20) was scored the highest by the panelist in terms of sensory aspect. The best product sample C had total soluble solids (TSS) of 31 ± 2 °Bx, total ash content of 2.482 ± 0.001 %, acid insoluble ash of 1.0013 ± 0.002 %, crude protein of 0.5902 ± 0.004 %, crude fat of 0.3514 ± 0.003 %, crude fiber of 0.8991 ± 0.003 %, carbohydrate of 95.67 ± 0.04 %, vitamin C of 24.24 ± 0.1 mg/100g, total energy of 338.11 ± 0.04 Kcal/100 g, total phenolic content (TPC) of 6.105 ± 0.001 mg GAE/g of dry extract, total flavonoid content (TFC) of 1.125 ± 0.002 mg QE/g of dry extract and DPPH scavenging activity of 27.268 ± 0.001 %. Panelists responded favorably to the prepared product samples.

Dynamic Analysis of UPLC-MS/MS for Sugar and Organic Acid Components of Pears with Different Flesh Texture Types During Development

Pears are popular among consumers for their juicy and delicious taste. In this study, the sugar and organic acid compositions of pear fruits with different texture types during development were determined by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS), and fruit texture traits were determined by a texture analyzer. The results showed that the dominant sugar in soft and crispy types of pear fruits was fructose. The main difference between pears was the second-highest sugar component; glucose content was higher in crispy-flesh pear fruits while sucrose content was higher in soft-flesh pear fruits. The composition of organic acid components in both texture types of pear fruits was similar. The turning points of changes in the content of sucrose, sorbitol, glucose and quinic acid were different between different-textured pear varieties. A Pearson correlation analysis showed that sugar and organic acid components were significantly correlated with single fruit weight and soluble solid contents (SSCs), respectively. There was a high correlation among texture traits, individual sugars and organic acids. A partial least squares discriminant analysis (PLS-DA) VIP score plot showed that the differential traits with scores greater than 1 were total soluble sugars/total organic acids (TSSs/TAs), fracture and malic acid/citric acid (MA/CA), which could distinguish pear fruits of different texture types better and reflect the uneven quality differences among pear fruits adapted to different origins. The comprehensive analysis results of the flesh texture parameters and sugar and organic acid components are in line with objective reality and will provide a reference for quantitative indicators of the sensory evaluation of pear varieties as well as for molecular mechanism research on trait differences.

Declaration of free sugars from fruits on food labels: a scoping review

PurposeThe World Health Organization recommends limiting the intake of free sugars, which can be added to packaged foods and may appear on labels under different terms. The aim of this research was to analyse the evidence related to the declaration of free sugars from fruits on packaged food labels.Design/methodology/approachA scoping review was conducted following the recommendations of the Joanna Briggs Institute (JBI).FindingsTen eligible studies, conducted in seven countries, were included in this review. The percentage of packaged foods in which free sugars were identified ranged from 52.5 to 86.5%. In three studies, terms related to sugars were identified inductively by reading the entire ingredient list, whereas in the other studies sugars were identified by searching for a list of predefined terms. Studies differed in the definition of sugars and the terms used to identify them. Nine studies included fruit sugars within the terms used to identify free sugars. However, they lacked consistency in the types of fruit sugars considered and did not discuss their agreement with the adopted definitions of sugars.Originality/valueAs far as can be ascertained, this is the first review that addresses the declaration of free sugars from fruits on packaged food labels. Overall, there is a scarcity of literature focused on identifying and discussing the range of free sugars from fruits declared on food labels.

Biochemical composition of three Opuntia species O. humifusa, O. phaeacantha, O. engelmannii var. lidheimeri. Prospects of their utilization

Relevance. Opuntia distinguished by high adaptability is widespread in many countries of the world. Tolerance to water deficiency and high biological activity provide prospects of its cultivation for food and pharmaceutical industry. In Russia Opuntia is grown in the Crimea, Caucasus, Donbass, Astrakhan region and even in the Central Russia. Evaluation of the Opuntia cultivation efficiency in the Crimea for various utilization supposes the importance of its biochemical characteristics which variability greatly depends on the place of habitat. Materials and Methods. Total antioxidant activity and titratable acidity were determined using titration methods, polyphenol content –using spectrophotometric method, monosaccharide and total sugar concentrations were assessed via reaction with ferricyanide, mucilage levels were determined gravimetrically.Results. Investigation of cladode, inflorescence and fruit biochemical parameters of three Opuntia species: O. humifusa, O. phaeacantha, O. engelmannii, – gathered at the Southern and South-Eastern part of the Crimean peninsular revealed wide variability of fruit mucilage (4.3-16.56% d.w.), sugar and total antioxidant activity. Polyphenol content decreased according to: inflorescence (18.4-21.0) > fruit (11.7-18) > cladodes (10.2-20.0). Fruit monosaccharide content reached (6.2-31) % while in cladodes these values were in the range of 8.1-16.0%. Total sugar content was equal to 32.6-95% in fruit and 15.5-29.7% in cladodes. Concentration of selenium as a natural antioxidant was higher in the cladodes (102-176 µg/kg d.w.) than in fruit (46.8-72 µg/kg d.w.). The highest levels of the total antioxidant activity and titratable acidity were registered in O. engelmannii while the highest sugar, mucilage and taste index were typical for O. humifusa. Nevertheless, O. humifusa was characterized by the lowest fruit mass (6.0-6.3 g) contrary to O. engelmannii (36-40 g). The results suppose prospects of fruit, cladode and inflorescence utilization in food industry, cosmetics and pharmacology with the preference to O. humifusa.