Search Results (61)

The freshwater drum (Aplodinotus grunniens) is a promising aquaculture species due to its strong environmental adaptability, tolerance to low temperatures, rapid growth rate, high nutritional value, high-quality texture (garlic-clove-shaped flesh), and absence of intermuscular bones. Nevertheless, processing technologies related to freshwater drum remain largely unexplored. Salting pretreatment serves as a viable strategy for enhancing the quality attributes of frozen fish products. This study investigated the effects of different sodium chloride (NaCl) pickling concentrations (0.25, 1, and 3 mol/L) on the physicochemical properties and quality attributes of frozen–thawed freshwater drum (Aplodinotus grunniens). Results indicated that elevated NaCl concentrations (1–3 mol/L) significantly (p < 0.05) shortened the transit time through the maximum ice crystal formation zone during freezing, effectively mitigating structural damage to myofibrillar networks. As the NaCl concentration increased from 0 to 3 mol/L, the water content decreased from 71.26 ± 0.22% to 68.64 ± 0.50%, while the salt content increased from 0.31 ± 0.01% to 8.46 ± 0.12%. Pickling pretreatment markedly enhanced water-holding capacity and improved texture profiles, including hardness, springiness, gumminess, and chewiness. Histological analysis revealed preserved myofibril integrity in high-salt-treated samples, supported by reduced fluorescence intensity of myofibrillar proteins, indicating mitigated freeze-induced denaturation. Low-field NMR confirmed salt-induced redistribution of water states, with decreased free water proportion. Our results identify that pretreatment with NaCl at concentrations ≥ 1 mol/L is an effective strategy to preserve the post-thaw quality. Due to 3 mol/L NaCl resulting in a relatively high salt content, 1 mol/L NaCl pretreatment is more suitable for maintaining the quality of freeze–thawed freshwater drums. Full article

While short-term faba bean feeding is known to improve fish texture, its long-term systemic effects and the underlying molecular mechanisms in Nile tilapia remain rarely explored. This knowledge gap is critical, given the potential for extended feeding to induce distinct metabolic reprogramming and trade-offs. Here, we present the first comprehensive study investigating the 180-day impact of a 60% FB-based diet (FBD) on Nile tilapia through an integrated analysis of phenotypic traits, muscle histology, metabolome, and transcriptome. Our results revealed a fundamental trade-off: FBD feeding induced hyperplasia-driven muscle remodeling, significantly enhancing textural properties (hardness, gumminess, chewiness) and increasing intramuscular fat and collagen content, but at the cost of suppressed growth and hepatosomatic index. Metabolomics identified 243 significantly altered metabolites, outlining a systemic metabolic shift characterized by activated lipid synthesis but inhibited amino acid and energy metabolism. This multi-omics integration nominated the chac1 gene as a novel key regulator for FB-induced muscle hyperplasia, a finding not previously reported in this context. We propose a mechanistic model wherein long-term FBD feeding coordinates lipid deposition, collagen accumulation, and chac1-mediated hyperplastic growth to remodel muscle texture. Our work provides new insights into the long-term metabolic trade-offs and molecular drivers of FB-induced flesh quality improvement, offering a theoretical foundation for developing optimized aquafeeds. Full article

Peach trees (Prunus persica L. Batsch) produce climacteric fruits that are prone to senescence and softening after harvesting, and they are susceptible to external pathogens that cause rot and deterioration. This study investigated the effects of 1-methylcyclopropene (1-MCP) treatment combined with laser microporous film (LMF) packaging on the preservation of firm-fleshed honey peaches (‘Xiahui No. 8’ variety) during refrigerated storage at 5 ± 1 °C. The combined 1-MCP + LMF treatment significantly reduced respiration and rot rates and preserved the levels of reducing sugar and titratable acid after 35 days more effectively compared to the control and LMF groups. The 1-MCP + LMF packaging suppressed cell-wall-degrading enzymes (polygalacturonase, β-glucosidase, and cellulase) and maintained high contents of original pectin, cellulose, and hemicellulose. The treatment also reduced the accumulation of superoxide anions and malondialdehyde, maintained cell-wall structural integrity and fruit hardness, and delayed fruit browning by inhibiting polyphenol oxidase and peroxidase activity. Together, our results demonstrate that the combination of 1-MCP treatment and LMF packaging effectively preserved the hardness and quality of firm-fleshed honey peaches during refrigerated storage, extending their shelf life to 28 days while maintaining good sensory and nutritional qualities. Full article

This study investigated the dynamic changes in fruit color, texture and quality attributes of blueberry cultivars during a 15-day postharvest storage period to provide theoretical insights for cultivar selection, postharvest preservation and commercial evaluation. Phenotypic and quality traits, including color parameters (CIE-Lab*), texture attributes (Note: hardness represents firmness and is an indicator in the Brookfield’s texture analyzer), adhesive force and physicochemical indices, were systematically analyzed using a colorimeter, texture analyzer and conventional methods. Principal component analysis (PCA) and cluster analysis were applied to evaluate postharvest performance. Southern highbush cultivars, including ‘EB 9-2’, ‘Meadowlark’, ‘Primadonna’, ‘Eureka’ and ‘Camellia’, exhibited superior comprehensive quality, characterized by small fruit shape index, minimal scar sizes and stable hardness dynamics. During the storage period, ‘Legacy’ demonstrated optimal color stability (ΔE < 3.5 from days 0–15), while ‘EB 9-2’ showed the most significant hardness increase. Scar size, fruit shape index and flesh elasticity were identified as key indicators for analyzing shelf-life hardness variations, offering scientific guidance for cultivar selection and postharvest management. Full article

To address the prominent issues in current potato peeling processes (such as high labor intensity, excessive flesh loss, hard-to-remove peel from bud eyes/concaves), a non-contact waterjet method was proposed. Based on the computational fluid dynamics (CFD) method, the Fluent software was used to simulate and analyze the flow field of fan-shaped nozzle models with different slot angles. The simulation results indicated that the 25° scattering angle nozzle had excellent performance: it ensured effective potato surface coverage and minimized jet energy loss, fitting peeling needs. A one-way fluid–structure interaction (FSI) model of the nozzle–potato system was built to study waterjet–potato mechanical interactions. Surface stress distribution under waterjet impact was analyzed, and jet dynamic pressure was mapped to solid stress via FSI interface load transfer. Simulations revealed that with a 25° scattering angle, 200 mm standoff distance, and 5 MPa pressure, the maximum shear stress at potato surface characteristic points was 0.032 MPa—within the 0.025–0.04 MPa target range and matching potato skin–substrate peeling strength threshold. This confirmed the energy–mechanical response coordination, validated by experiments. The research results can provide an effective technical reference for potato peeling processing. Full article

This study utilized high-voltage electrostatic field (HVEF) treatment combined with cold storage to preserve Agaricus bisporus, characterized by high water content and susceptibility to browning, cap opening, and mechanical injury. Key quality indicators, such as surface and flesh color, weight loss, respiration rate, hardness, and soluble solids, were monitored to determine optimal HVEF intensities. Transcriptomic, physiological, and biochemical analyses were used to reveal the underlying preservation mechanisms. This study demonstrates that high-voltage electrostatic field (HVEF) treatment at 30 kV m⁻¹ combined with cold storage effectively delays browning, weight loss, and respiration rate in A. bisporus while maintaining color, texture, and flavor. Transcriptomic analysis revealed that HVEF modulates key metabolic pathways, including ATP synthesis, fatty acid metabolism, and redox enzyme activity, leading to reduced ATP levels, suppressed respiration, and delayed senescence. Additionally, the treatment enhances antioxidant capacity through increased ascorbic acid (AsA) and glutathione (GSH) levels, while decreasing malondialdehyde (MDA) content and membrane electrical conductivity, thereby preserving membrane integrity. The suppression of polyphenol oxidase (PPO) and peroxidase (POD) activities reduces pigment formation and browning. Furthermore, the active metabolism of osmoprotectants such as proline improves cold resistance. These findings provide a mechanistic basis for HVEF-based preservation strategies for A. bisporus, supporting its application in postharvest technology. Full article

Meat quality critically influences product value and consumer preferences. Here, the effect of long-term saline adaptation on flesh nutritional quality, sensory value, texture, and flavor was evaluated in a new Micropterus salmoides salt-tolerant population. The results showed that the salt-tolerant population exhibited decreased lipid, saturated fatty acid, and long-chain polyunsaturated fatty acid contents but increased monounsaturated fatty acid content, accompanied by upregulated elongase 5 and fatty acid desaturase 6 mRNA levels. The meat color of the new population was brighter and fresher, with a slightly less red tint, and the increased 2,3-butanedione content resulted in a desirable creamy aroma. 3-Pentanone was the most abundant volatile substance in both populations. Regarding taste parameters, the salt-tolerant population had improved hardness, stickiness, chewiness, resilience, cooking loss, myocyte space, and collagen content. Alanine, proline, and histidine were the main amino acids responsible for flavor presentation. The salt-tolerant population was found to have lower bitter and higher sweet amino acid contents. Higher umami nucleotides and lower pH intensified umami and sourness in salt-tolerant meat. The saltiness of the new-population meat was enhanced. This study comprehensively evaluated the flesh quality of a salt-tolerant M. salmoides population with the potential for cultivation, thereby providing a reference for its potential development as an alternative aquaculture strain. Full article

This study aimed to reveal the lipid composition and distribution and characterize the lipid metabolism profile in the three distinct parts of four guava varieties with varying textures and colors using liquid chromatography–electrospray ionization–tandem mass spectrometry. The four varieties, collected from a guava cultivation base in Danzhou City, Hainan Province, were “Zhenzhu” (white-fleshed hard-crispy guava, YBSL), “Bendi” (white-fleshed soft-waxy guava, RBSL), “Xiguahong” (red-fleshed hard-crispy guava, YHSL), and “Hongxin” (red-fleshed soft-waxy guava, RHSL). A total of 8242 lipids were detected, which were classified into four categories and 20 subcategories. Glycerolipids and glycerophospholipids are the most abundant types of lipids in guava. The lipid composition showed significant differences between hard-crispy and soft-waxy guavas. The red-fleshed guava varieties had 98, 57, and 96 differential lipid metabolites, whereas white-fleshed varieties had 68, 108, and 41 lipid metabolites in the epicarp, mesocarp, and endocarp, respectively. Moreover, comparative analysis of hard-crispy versus soft-waxy guavas with different colors revealed common differential lipids in the epicarp (29), mesocarp (21), and endocarp (18). The common differential lipids, including phosphatidylcholine (PC) (16:0/18:1), PC (18:1/18:1), and phosphatidylethanolamine (PE) (18:1/18:2), were found to be upregulated across all fruit parts, with greater abundance in soft-waxy guavas. They were mainly enriched in metabolic pathways associated with glycerophosphocholine and glycerophosphoethanolamine. These differential lipids may serve as potential biomarkers for evaluating guava quality. This study unveiled the lipid distribution and metabolic variations among different guava varieties. It also established a scientific foundation for improving guava varieties and implementing quality control measures. Full article

The fruits of the common quince (Cydonia oblonga) have wide-ranging health benefits due to their valuable composition. However, consumers usually do not welcome the hard flesh and astringency, so the fruit is not eaten raw. Therefore, it is important to choose the proper method for processing, including heat treatment, to preserve the high quality of the common quince fruit. The study examined the effects of freeze drying and convection drying at two temperatures (40 °C and 60 °C) on selected physicochemical, bioactive, and antioxidant properties of Cydonia oblonga fruits. It was found that freeze drying allowed the processed fruit to retain properties most similar to fresh fruit. This variant had the highest rehydration rate (3.53 ± 0.04), the lowest shrinkage rate (9.87 ± 0.29%) and the lowest bulk density (0.41 ± 0.01 g/cm³). Freeze drying preserved the brightest fruit colour (L* = 75.70 ± 1.71). These samples also had the highest total acidity (1.34 ± 0.01 g/100 g DM). Drying reduced the fruit’s tannin content, but no statistically significant differences were detected between freeze-dried and convection-dried samples at 40 °C and 60 °C. Freeze-dried quince fruits retained a high content of polyphenols (233.56 ± 5.96 mg GEA/100 g DM), flavonoids (36.79 ± 0.74 mg EPI/100 g DM), and antioxidant activity against ABTS (364.51 ± 9.12 µM Trolox/100 g DM) and DPPH (258.78 ± 5.16 µM Trolox/100 g DM). The highest losses of the mentioned bioactive compounds, and thus of antioxidant activity, were recorded in samples dried by convection at 60 °C. Full article

Flesh texture is an important quality trait and is related to people’s preference for fruit, especially for crisp pears. Puncture tests were carried out on 156 crisp pear fruit germplasm samples to analyze the diversity level of texture traits, to clarify the correlation between sensory description evaluation and instrumental traits, and to explore the effects of fruit ripening, size, and shelf life on the change in flesh texture. The results showed that puncture parameters were significantly different between crisp pear cultivars, and the work associated with the flesh limit compression force had the highest coefficient of variation (0.281). There was a significant correlation between puncture parameters and sensory evaluation scores. The correlation between sensory score and flesh firmness was the highest, with a correlation coefficient of 0.708, indicating that hardness can significantly influence the sensory evaluation of texture. Cluster analysis based on sensory evaluation and puncture determination could divide the germplasm resources of crisp pear into five texture categories: loosen, crunchy, crisp, tight–crisp, and dense. A comprehensive texture score model, constructed by principal component analysis, showed consistency with sensory evaluation scores and proved that the combination of a puncture test and sensory evaluation is the best way to identify and evaluate the texture of crisp pear. Further analysis of the influencing factors of flesh texture showed that fruit maturity and shelf life had significant effects on flesh quality. This study provides an important reference for the standardization, evaluation, and utilization of crisp pear variety resources. Full article

Apples (Malus domestica Borkh.) represent one of the most widely cultivated and consumed fruits globally, with significant genetic diversity among cultivars. This study aimed to evaluate the morphological, biochemical, and organoleptic characteristics of 34 apple cultivars, including ancient Romanian varieties, internationally old and modern cultivars, and new selections. The assessment was conducted to identify valuable traits for breeding programs and commercial applications. Morphological analysis revealed significant variation in fruit size, shape, and weight, with international ‘classic’ cultivars exhibiting larger dimensions on average. Biochemical profiling indicated notable differences in moisture content, total soluble solids, titratable acidity, and carotenoid levels, with some traditional cultivars demonstrating high nutritional potential. Texture analysis showed variations in peel hardness, flesh firmness, and toughness, influencing storage capacity and consumer preference. Organoleptic evaluations highlighted the superior sensory attributes of cultivars such as ‘Golden Orange’, ‘Jonathan’, ‘Kaltherer Böhmer’, and ‘Golden Delicious’, which ranked highest in terms of taste, aroma, and juiciness. Statistical analyses, including principal component and hierarchical clustering analyses, further distinguished cultivars based on their physicochemical and sensory profiles. The findings emphasize the importance of genetic diversity in apples in maintaining a resilient and sustainable assortment. This study provides valuable insights for breeding programs and for orchard, market, and apple industry development. We also highlight future directions, promoting the conservation and strategic use of both traditional and modern cultivars. Full article

Background: Millet peppers have rich and diverse germplasm resources. It is of great significance to characterize their phenotypes and physicochemical indicators. Methods: 30 millet germplasms were selected to measure the fruit length and width, flesh thickness, number of ventricles, fruit stalk length, and single fruit weight, and the texture characteristics of fruit such as hardness, cohesiveness, springiness, gumminess, and chewiness were determined by a texture analyzer. At the same time, high-performance liquid chromatography (HPLC) and gas chromatography (GC) were used to determine the fruit of capsaicin, dihydrocapsaicin, nordihydrocapsaicin, fatty acids, vitamin E (VE), total phenol, total sugar, and total dietary fiber. Results: M11 showed outstanding parameters in phenotype and texture. The coefficient of variation (CV) for VE was as high as 94.943% and the highest diversity index (H’) was total soluble solid, at 1.988%. M5 and M18 contained rich and diverse fatty acids. At the same time, the content of capsaicinoids in M18 also ranks among the top, second only to M27 (with a total capsaicin content of 5623.96 μg/g). PCA analysis using phenotypic data and physicochemical data showed that the classification results were different. Further hierarchical group analysis was carried out using all the index data. The results showed that 30 millet pepper germplasms were divided into three new categories: M5, M9, M18, and M24 formed one group (C1), M10, M14, M16, M19, M20, M22, M25, M26, M28, M29, and M30 formed another cluster (C2), and the remaining germplasms formed a third cluster (C3). Among them, the abundance of fatty acids in the C1 germplasm was higher than that in the other two groups. Conclusions: Our study showed that different germplasms had significant differences in morphological traits and nutritional metabolic components and were rich in genetic diversity. This study provides a theoretical basis for the improvement of millet varieties and the development of functional food. Full article

The aim of this study was to investigate the effect of foliar application of calcium and salicylic acid on improving the physicochemical quality, sensory quality and antioxidant potential of pepper fruits grown hydroponically in mineral wool substrate. Two sweet pepper varieties with red fruit type were used: block Aifos and elongated Palermo. Fruit quality was tested from four plant treatment combinations: (1) water (control), (2) calcium nitrate 0.7% (Ca), (3) salicylic acid 0.03% (SA), (4) calcium nitrate and salicylic acid combined (Ca+SA). Fruits of both varieties showed high concentrations of health-promoting constituents, including potassium, phosphorus, vitamin C (over 47 mg 100 g⁻¹ of FW (fresh weight)), and carotenoids, with capsanthin being the most abundant (more than 1226 μg 100 g⁻¹ of FW). The results of the sensory evaluation demonstrated that the attributes tested scores above 7 out of 10, indicating a high sensory quality. The antioxidant activity of pepper fruits was determined by three different methods: DPPH (method for measuring the antioxidant activity of DPPH), ABTS (method for measuring the antioxidant activity of ABTS) and TPC (total polyphenol content) and averaged more than 86%, 78% RSC (radical scavenging capacity) and almost 54 mg CE (catechin) 100 g⁻¹ of FW for both cultivars, respectively. Fruit quality results were analysed using PCA (principal component analysis). The first two principal components (PC1 and PC2) explained almost 54% of the variation, highlighting the strong correlations of PC1 with dry matter content, soluble sugars, potassium, acidity and sensory characteristics of pepper fruit such as skin hardness and flesh firmness. The application of SA to peppers resulted in an increase in the carotenoid content of the fruit. Furthermore, a notable positive correlation was detected between total sugars and the sugar/acid ratio when Ca+SA was combined in both cultivars. Palermo fruit showed better quality parameters and higher antioxidant activity, making this sweet pepper variety particularly valuable in a health-promoting context. Full article

The aim of this study was to establish a standardized and unified method for identifying and evaluating jujube fruit texture quality and to provide a theoretical basis for determining the texture quality of jujube germplasm resources. The texture of 56 jujube germplasms was characterized via the texture profile analysis (TPA) method, and the texture and anatomical structure of three each of the hard- and soft-fleshed germplasms were analyzed. Cluster analysis was used to categorize the 56 germplasms into hard- (17) and soft-fleshed jujubes (39). Significant positive correlations were found between all other textural parameters of jujube fruits except adhesiveness. The hardness, springiness, and chewiness of the full-red period hard- and the soft-fleshed jujube fruit were lower than those of the half-red period. The hardness, adhesiveness, and chewiness of the hard-fleshed jujube fruits in the full-red period were 2.13–3.57, 3.00–4.99, and 4.39–9.58 times higher than those of the soft-fleshed jujube fruits, respectively. The findings of this study provide a theoretical foundation for the evaluation and classification of the texture and quality of jujube fruits and a basis for the breeding of new, high-quality jujube varieties with distinctive characteristics. Full article

Carnosine is a natural dipeptide made up of L-histidine and β-alanine which is rich in muscle tissues and has multiple physiological functions. The current research aimed to investigate the effects of varied carnosine concentrations in low-fishmeal feed on the growth, muscle antioxidant capacity and flesh quality of orange-spotted grouper. Carnosine was supplemented at doses of 0, 10, 20, 40, 80, 160, and 320 mg/kg in low-fishmeal feed. Seven groups with three tanks of fish (11.4 ± 0.1 g/fish) were allotted one of the diets during the 8-week feeding trial. The growth rate, body protein content, muscle activities of superoxide dismutase and catalase, and muscle adhesiveness showed positive linear response and/or an open upward parabola with increasing carnosine concentrations, with a peak at 160 mg/kg of carnosine. Feed utilization, serum total protein content, gut trypsin activity, muscle glutathione peroxidase, total antioxidant capacity, muscle hardness, gumminess, chewiness and resilience followed the same pattern as the growth rate, reaching a peak at 320 mg/kg of carnosine; while the opposite trend was observed, reaching a minimum at 320 mg/kg for muscle malondialdehyde and 160 mg/kg for muscle liquid and water loss. The results indicated that appropriate carnosine addition could improve growth performance, muscle antioxidant capacity and flesh quality of grouper. The suitable inclusion concentration was estimated to be 195.14 mg/kg to achieve the best percent weight gain. Full article