Acceleration of the ageing process in mei (Prunus mume Siebold) liqueur by high hydrostatic pressure treatment

This study evaluated the effects of high hydrostatic pressure (HHP) treatment on the physicochemical composition, level of aromatic compounds and antioxidant properties of mei liqueur, as well as the microstructure of mei fruits during a 180-day ageing process. The titratable acidity, pH, and browning index of mei liqueur and HHP-treated mei liqueur did not exhibit significant differences. The HHP-treated mei liqueur displayed significantly higher ∆E, sugar and alcohol concentration during the 180-day maceration period (P ≤ 0.05). Electron microscopy revealed that HHP treatment damaged the cellular structure of mei fruits, promoting the penetration of rice wine into the fruits as well as the dissolution of aromatic and antioxidant components into rice wine, leading to the completion of the maturation of the mei liqueur. Thus, HHP technology could be used to accelerate mei liqueur maturation, shorten the time required for its ageing, exhibiting tremendous potential for applications in the liqueur industry.     

Development of multiresidue DLLME and QuEChERS based LC–MS/MS method for determination of selected neonicotinoid insecticides in honey liqueur

Honey liqueur is an alcoholic drink derived from honey and strong fruit brandy of suitable type, traditionally made in Serbia and other Balkan countries. Although European Union has regulated the levels of neonicotinoid insecticides in honey and pollen, there is an increased risk of the presence of these compounds in traditional products made from honey. The objective of this study was to develop an optimized LC–MS/MS analytical method with dispersive liquid–liquid microextraction (DLLME) and QuEChERS sample preparation procedures for analysis of seven neonicotinoids (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid) in honey liqueur. The LC–MS/MS conditions were optimized to unequivocally provide good chromatographic separation, selectivity and specificity of developed method. The method was validated to fulfill the requirements of SANCO/12495/2011 for both sample pretreatment procedures providing results for accuracy (R, 69.2–113.4% for DLLME; 71.8–94.9% for QuEChERS), precision (RSD expressed in terms of repeatability (3.21–10.20% for DLLME; 4.19–12.81% for QuEChERS) and within-laboratory reproducibility (9.11–16.63% for DLLME; 11.32–16.40% for QuEChERS)), limits of detection (LOD, 0.5–1.5 μg L^− 1 for DLLME; 1.0–2.5 μg L^− 1 for QuEChERS) and quantification (LOQ, 1.0–5.0 μg L^− 1 for DLLME; 2.5–10.0 μg L^− 1 for QuEChERS). Matrix effects were compensated by the use of matrix-matched calibration. Analysis of real honey liqueur samples obtained from local markets showed the presence of clothianidin or thiacloprid in four of the analyzed samples, therefore implicating the necessity of ongoing control of this type of traditional product.     

Antioxidant capacity and phenolics of <Emphasis Type="Italic">Pouteria macrophylla</Emphasis>, an under-utilized fruit from Brazilian Amazon

The potential of fruits occurring in the Amazon with regard to their antioxidant capacity is being addressed increasingly during the last years. In this paper, the antioxidant capacity of fruits from Pouteria macrophylla (cutite) and the compounds which are responsible for that functional property were studied. Diphenyl-picrylhydrazyl (DPPH) and total oxidant scavenging capacity (TOSC) assays were used for the evaluation of antioxidant capacity of fruit aqueous extracts. TOSC assay showed inhibitory effects against peroxyl (TOSC_50% = 560 mg/L) and peroxynitrite (TOSC_50% = 830 mg/L), two important reactive oxygen species, while DPPH showed that cutite (EC₅₀ = 300 ± 3.9 g/g DPPH) has significant antioxidant capacity, greater than many other known Amazon fruits. It was also seen that the cutite fruits are a good alimentary source of polyphenols (867 ± 8 mg GAE/100 g), analyzed by Folin-Ciocalteu assay. Using HPLC-DAD-ESI-MS ⁿ and HPLC-DAD, gallic acid (4.72 mg/g fresh fruit pulp) and digalloyl glucose were found as the main phenolic compounds in the cutite fruits. TOSC assays with HPLC fractions of fruit aqueous extracts show that both compounds are predominantly responsible for the antioxidant capacity observed in the cutite.     

Simultaneous determination of anthocyanins,coumarins and phenolic acids in fruits,kernels and liqueur of Prunus mahaleb L

In the fresh tissues of Prunus mahaleb L., three classes of phenolics were characterised: phenolic acid derivatives (main compound being o-coumaric acid glucoside), quercetin glycosides, and anthocyanins (cyanidin 3,5-diglucoside, cyanidin 3-sambubioside, cyanidin 3-xylosyl-rutinoside and cyanidin 3-rutinoside). Coumarin was also identified. The kernels showed a high content of coumarin (0.87 mg g^?1) which is the main class of metabolites in this sample, but present in pitted berries as well (0.63 mg g^?1). Flavonoids are mainly concentrated in the skin and pulp (0.55 mg g^?1). In ‘Mirinello di Torremaggiore’ liqueur, produced from P. mahaleb L. in accordance with traditional procedures, anthocyanins make up 16.5%, phenolic acids 43.3%, coumarin 36.2% and flavonoids 4% of total compounds. Anthocyanins are the main class in solid residues from liqueur production (70%). These findings point out that solid residues of P. mahaleb can be considered an interesting and innovative source of appreciable amounts of cyanidin glycosides (3.3 mg g^?1).     

Change in anthocyanin concentrations in red apricot fruits during ripening

Here we report on accumulation patterns of anthocyanins and of β-carotene during fruit maturation, between 82 and 125 days after flowering, of two apricot (Prunus armeniaca L.) cultivars, A3576 and A3751. Both cultivars displayed an intense red colour of the skin but differed in their genetic background. The pigments were extracted from skin and flesh, separately, and analysed using HPLC-DAD-MS. Out of three anthocyanins detected here, the major compound, cyanidin-3-O-rutinoside was present at 75%. The two minor compounds were cyanidin-3-O-glucoside and peonidin-3-O-rutinoside. This is the first time that peonidin-3-O-rutinoside has been detected in apricot fruit. During maturation, A3751 accumulated anthocyanins in both skin and flesh, whereas anthocyanins were present only in the skin of A3576. The skin anthocyanin content was higher in A3751 (296 mg kg⁻¹) than in A3576 (41 mg kg⁻¹). Maximum anthocyanin levels were attained after 108 and 118 days of flowering in A3751 and A3576, respectively, in conjunction with loss of firmness and red colour acquisition on the un-blushed side of the fruit. At the end of ripening, the β-carotene flesh concentration reached 5 mg kg⁻¹ in A3576 and 15 mg kg⁻¹ in A3751. A significant effect of environment was observed on the anthocyanin content in the two cultivars.     

Water dynamics of turbot flesh during frying,boiling, and stewing processes and its relationship with color and texture properties: Low‐field NMR and MRI studies

Water dynamics in turbot flesh during frying, boiling and stewing was assessed by nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) techniques. Protons associated with different types of water were distinguished by T₂ relaxation spectra, and significant differences of water mobility were detected. Principle component analysis revealed a clear discrimination between samples of different cooking methods. MRI provided further visualization of internal information for turbot flesh during cooking. The linear regression analysis demonstrated a strong correlation between the NMR parameter A₂₃ and b* value (R² = .972) during frying process, A₂₃ and L* (R² = .963), T₂₂ and b* (R² = .991) during boiling process, T₂₂ and b* (R² = .883) during stewing process. Moreover, a good correlation was found between A₂₁ and cohesiveness (R² = .924) during the frying process, A₂₃ and resilience (R² = .879) during boiling process, as well as between A₂₃ and chewiness (R² = .946) during stewing process.

Practical applications

Water mobility and distribution can significantly affect turbot flesh physical and biochemical status leading to change the texture, color, tenderness and taste during cooking process. Therefore, it is very important to develop a fast, nondestructive method to monitor the water dynamics, reduce the cooking time, save energy and visualize the structure change of turbot flesh during cooking. In this study, a rapid and nondestructive NMR and MRI method were developed to analyze the water dynamics of turbot flesh during frying, boiling and stewing for the first time. The water states, distribution and mobility were analyzed by the NMR and MRI. Different cooking methods displayed different water dynamics in turbot flesh, which could be identified when NMR combined with chemometrics principal component analysis. The facile method by using both NMR and MRI for analysis of turbot flesh may have great potential for rapid and nondestructive analysis of other food processing.     

Prediction of Japanese color score

Relationships between Japanese color score (JCS) and pork quality attributes were studied and three equations were developed to predict JCS. Averages for population one (n = 781) traits were used to develop initial prediction equations and traits from population two (n = 684) were used to evaluate the success of the prediction equations. The first equation was: JCS = 12.698 − (0.01128 × firmness) + (0.09008 × pH) − (0.00007199 × drip loss) − (0.266 × L^*) + (0.06923 × a^*) − (0.201 × b^*) + (0.02143 × hue angle); r² = 0.916. The second equation was: JCS = 15.255 − (0.259 × L^*) − (0.213 × b^*) + (0.02518 × hue angle); r² = 0.931. The third equation was: JCS = 12.920 − (0.219 × L^*) + (0.07342 × a^*) − (0.02166 × b^*); r² = 0.906. All equations predicted 92% or more Japanese color scores within ±0.50. Requiring fewer measurements, the second and third equations would be advantageous when sorting pork on the basis of JCS.     

Traditional walnut liqueur – cocktail of phenolics

The phenolic composition in walnut husks of the Slovenian cultivar Elit, which is a basic material for the traditional making of walnut liqueur, was investigated by HPLC with a PDA detector. Four different samplings of green husks were performed on different dates in order to compare the contents of phenolic compounds. The 2nd sampling coincided with the picking time of walnut fruits intended for the making of liqueur. Phenolic composition of walnut liqueur was investigated as well. Thirteen phenolic compounds were identified in walnut husks: chlorogenic acid, caffeic acid, ferulic acid, sinapic acid, gallic acid, ellagic acid, protocatechuic acid, syringic acid, vanillic acid, catechin, epicatechin, myricetin, and juglone. In walnut liqueur, 1,4-naphthoquinone was also identified. The major phenolic in the husks was juglone with the highest content in the 2nd sampling; its content in walnut liqueur was low. The concentrations of individual phenolics in the liqueur were quite low compared with the contents in the green husks, due to the traditional way of making the liqueur.     

LC/MS/MS detection of fungicide guazatine residues for quality assessment of commercial citrus fruit

An analytical protocol was developed for investigating guazatine occurrence in citrus fruit with the aim of controlling the import of treated fruits in countries where the use of this fungicide is forbidden. The main constituents of guazatine mixture (GN, GG, GNG, GGN, GGG, GGGN and GGGG) and the internal standard (dodine) were separated by high performance liquid chromatography using a hydrophilic end-capped Aquasil C₁₈ column and detected by ESI/MS/MS of parent ions, operating in positive mode. Extraction from citrus peels was performed with 1% HCOOH in water/acetone (1:2 v/v). The analytical method was statistically validated on three of the main constituents (GG, GGN and GGG) representing more than 65% of the total content. The regression lines, ranging from 0.100 to 3.750 mg/L of total guazatine, showed r ² > 0.990. Recoveries of about 81, 90 and 104% were obtained on average for the fortification level of 0.010, 0.035 and 0.060 mg/kg, respectively; the relative standard deviations ranged from 2 to 8% (n = 6). The limit of detection was below 0.0050 mg/kg, while the limit of quantification did not exceed 0.0065 mg/kg. The method was successfully applied to 77 samples of extra-European citrus fruit collected in the Italian market during the summer 2007. The results demonstrated that 64% of the investigated citrus samples contained guazatine over the residue limit value of 0.010 mg/kg for not allowed pesticides, evidencing the alarming illicit employ of this fungicide in citrus post-harvest treatments.     

Melatonin-mediated postharvest quality and antioxidant properties of fresh fruits: A comprehensive meta-analysis

At postharvest, fruits have a short shelf life. Recently, there has been much literature on the effects of melatonin on the postharvest quality of horticultural crops. However, reports of various findings comprise mixed claims and product-specific conclusions. Therefore, a meta-analysis systematically dissects the comprehensive effect on several fruits. In this meta-analysis, standard mean difference (SMD) was adopted using a random-effect model. The study used 36 articles and isolated 24 indicator parameters of postharvest quality and antioxidant properties based on the inclusion criteria. As exhibited in the forest plot, melatonin reduced chilling injury, weight loss, respiration rate, and ethylene content (SMD −0.90, 95% CI [−1.14, −0.65]; I² = 81%; p < .00001). Similarly, the application of melatonin significantly suppressed electrolyte leakage, malondialdehyde (MDA), hydrogen peroxide, superoxide anion, lipoxygenase, and polyphenol oxidase (SMD −0.89, 95% CI [−1.09, −0.69]; I² = 70%; p < .00001). In addition, exogenous melatonin application induced endogenous melatonin content, phenolic content, and flavonoid and anthocyanin contents (SMD 1.15, 95% CI [0.91, 1.39]; I² = 71%; p = .01). Moreover, melatonin treatment enhanced antioxidant activities (catalase, superoxide dismutase, peroxidase, ascorbate peroxidase, and phenylalanine ammonia-lyse) (SMD 1.37, 95% CI [1.03, 1.71]; I² = 86%; p < .00001). Thus, in the whole study, the overall effect was significantly high in treated fruit (p < .0001), and the overall heterogeneity was above (I²) > 70%. In addition, the funnel plot showed symmetry in the most selected studies. To sum up, the result gives a further understanding of melatonin's capabilities in reducing postharvest losses and maintaining the quality of fresh fruits.     

Polycyclic aromatic hydrocarbons (PAH) in various types of tea

For the analysis of the 16 PAH (EFSA-PAH), which are classified as priority for different food groups by the Scientific Committee on Food (SCF) and the Joint FAO/WHO Experts Committee on Food Additives (JECFA) in tea, a sensitive analytical Fast-GC/HRMS method was used. The sample preparation included accelerated solvent extraction (ASE) and the highly automated clean up steps, gel permeation chromatography and solid phase extraction. The analytical parameters, limit of detection (0.01–0.02 μg/kg) and limit of quantification (0.03–0.06 μg/kg), were determined. The repeatability (RSD, n = 3) of different PAH in fruit tea ranged from 0.1 to 11%. It was observed that the total contents of the 16 PAH in tea samples ranged from 14 to 2,662 μg/kg. The analysed tea samples showed an increasing presence of PAH in the following order: herbal and fruit tea (n = 7) < black tea (n = 11) < green tea (n = 11) < white tea (n = 3) < mate-tea (n = 8). The correlation coefficient (R) between BaP and the sum of the 16 EFSA-PAH was established considering the contamination amount in all the 40 tea samples analysed.     

Change regime of aroma active compounds in response to pulsed electric field treatment time,sour cherry juice apricot and peach nectars,and physical and sensory properties

Regime (direction, amount, rate, and pattern) of change in aroma active compounds was quantified as a function of four pulsed electric field (PEF) treatment times, three fruits, and 10 physical and eight sensory properties using the best-fit multiple linear regression (MLR) models. The PEF treatment times did not deteriorate 94% of the sensory properties and 70% of the physical properties and significantly change 57% of a total of 73 aroma active compounds detected for sour cherry juice, and apricot and peach nectars. The best performing MLR models belonged to 1-methyl-4-prop-1-en-2-ylcyclohexene as a function of fruit type, treatment time, and titratable acidity (= 49 mg/L; R_adj² = 95.7%; R_cv² = 94.9%) and to 2-[(2S,5S)-5-ethenyl-5-methyloxolan-2-yl]propan-2-ol as a function of fruit type, and treatment time (SE = 157 mg/L; R_adj² = 98.2%; R_cv² = 98.0%), respectively (n = 48; p < 0.001).Industrial relevancePulsed electric field (PEF) is one of the leading nonthermal food technologies especiallyfor processing of high acid low viscosity foods with satisfactory quality and microbial inactivation. It was shown in this study that PEF with different treatment times can successfully be applied in the pasteurization of sour cherry juice, and apricot and peach nectars with minimum loss of aroma active compounds and sensory and physical properties. Both PEF processing conditions and results can be used as a guide to determine PEF processing parameters for industrial scale processing of juices/nectars.     

Effects of gastrointestinal digestion models in vitro on phenolic compounds and antioxidant activity of juçara (Euterpe edulis)

This study evaluated the effects of different gastrointestinal digestion models in vitro on the bioaccessibility of phenolics and antioxidant activity in juçara frozen pulp. In the sequence, method 3 was applied to juçara fruit in three different stages of maturation (vitrin – reddish fruits, mature – purple fruits, tuíra – deep purple fruits). In the method applied, the final pH adopted was 5.0, in order to avoid interference in the assay used to determine the antioxidant activity, and BHT was used to prevent excessive oxidation in the system. In this method, higher values for antioxidant activity were obtained (3574.95–3719.10 μmol L^?1 Trolox 100 g^?1 pulp) compared with the other two methods tested (1969.14–3034.74 μmol L^?1 Trolox 100 g^?1 pulp). In relation to juçara fruit, the mature stage was found to be ideal for processing, showing generally higher values of the bioaccessibility for phenolics and antioxidant activity compared to other maturation stages.     

Total phenolic compounds and antioxidant capacities of major fruits from Ecuador

Seventeen fruits from Ecuador were analysed for total soluble phenolic compounds content and for antioxidant capacity, using three different methods (DPPH, FRAP and ABTS⁺). For the total phenolic content measured by the Folin–Ciocalteu method, three groups, having <100, 200–500 and >1000 mg GAE/100 g FW, were clearly distinguishable. Andean blackberry, capulí cherry peel and banana passion fruit were classified in the third group, with concentrations of 2167, 1494 and 1010 mg of GAE/100 g FW, respectively. Antioxidant capacity analyses revealed the same classes. FRAP and ABTS⁺ gave comparable results and were highly correlated (y = 0.691x + 6.78; r² = 0.908). Spectrophotometric measurements showed that the Andean blackberry and capulí peel but not banana passion fruit contained high levels of anthocyanins (λ_max = 520 nm).     

Effects of harvesting seasons and maturity stages on internal characteristics of the mangosteen having different surface properties

Translucent flesh disorder is a major internal physical disorder of mangosteen. The internal characteristics of smooth‐ and coarse‐surface fruits in relation to their respective specific gravity values and sensory characteristics were evaluated for suitable grading process. Study on percentage of the internal characteristics was performed in different external characteristics, different harvesting seasons and different maturity stages of mangosteen. Results showed that internal physical disorders of smooth‐surface fruits were higher than coarse‐surface ones at the level of 63% and 19%, respectively. Average specific gravity of normal‐flesh fruits, mild translucent‐flesh fruits and moderate‐to‐severe translucent‐flesh fruits were observed as 0.97, 1.00 and 1.01, respectively. The sensory characteristics: sweetness, flavour and overall acceptability were significantly (P < 0.05) higher for coarse‐surface fruits compared with smooth‐surface fruits. Both results were inconsistent with market price in which smooth fruit was 50% higher than coarse‐surface fruit.     

Controlled and modified atmospheres influence chilling injury,fruit quality and antioxidative system of Japanese plums (Prunus salicina Lindell)

Our objective was to compare the effects of controlled atmosphere (CA) and modified atmosphere packaging (MAP) on fruit quality, chilling injury (CI) and pro‐ and antioxidative systems in ‘Blackamber’ Japanese plums. Matured fruit were stored for 5 and 8 weeks at 0–1 °C in normal air, CA‐1 (1% O₂ + 3% CO₂), CA‐2 (2.5% O₂ + 3% CO₂) and MAP (~10% O₂ and 3.8% CO₂). CA was more effective than MAP in retention of flesh firmness and titratable acidity during cold storage. Fruit stored in CA‐1 showed reduced CI and membrane lipid peroxidation after 5 and 8 weeks of cold storage. Low O₂ atmospheres appeared to limit the generation of reactive oxygen species (ROS) and their efficient scavenging through the concerted action of superoxide dismutase and peroxidase. The role of ascorbate–glutathione (AsA–GSH) cycle in the regulation of oxidative stress was also studied during and after storage in different atmospheres. In conclusion, optimum CA conditions delayed fruit ripening and CI through augmentation of antioxidative metabolism and suppression of oxidative processes.     

Processing of Xoconostle fruit (Opuntia joconostle) juice for improving its commercialization using membrane filtration

The aim of this study was to propose a membrane process for processing of a native Mexican fruit with limitations for its commercialization. The clarification of Xoconostle juice was performed using a hollow fiber membrane. The operating conditions were determined (T = 25 °C, Q_f = 58 L/hr, TMP = 138 kPa); the process presented high productivities in terms of permeate flux (12.0–19.7 kg/m²/hr). The proposed method achieved high retention of turbidity (87.50%); whereas low retentions of pH (0.98%), total soluble solids (10.17%), carbohydrates (33.17%), polyphenols (2.10%), betalains (5.52%), and antioxidant activity (15.74%) were observed. Finally, a clear juice (3.79 ± 1.3 NTUs) was obtained with high antioxidant activity (21.40 ± 1.1 TEAC), high phenolic (27.50 ± 0.2 mg gallic acid/L) and betalain contents (18.80 ± 0.6 mg/L). An enhancement on color properties was observed (redness grade, h° = 10.14 ± 2.0).

Practical applications

Nowadays, the interest of food industry is focusing on the development of functional foods as well as looking for new valuable sources rich in bioactive compounds. Until now, many native Mexican fruits have not been processed in agro‐food industry, that is, Xoconostle fruit is one of the natural products not strongly processed. The processing of its derivative products, as fresh juice, can offer benefits to exploit a bit more its well‐known functional properties to human health. The enhancement of the quality of this natural juice preserving its nutritional and biological properties can be carried out using pressure‐driven membrane processes. Based on (a) the high productivity of the applied methodology for juice processing, (b) the high removal of turbidity, (c) the enhancement of physical characteristics (colorimetric), and (d) the preservation of its natural chemical substances, the membrane filtration seems to be a good alternative to going further in the commercialization of the fruit.     

Discrimination of Kyoho grape (Vitis labruscana) skin,seed and flesh antioxidant activities by solvent extraction: application of advanced chemometrics

Grape skin, seed and flesh, a potential source of bioactive compounds, were investigated to discriminate Kyoho skin, seed and flesh antioxidant activities by solvent extraction using chemometrics, including multivariate, discriminant analysis (DA) and hierarchical cluster analysis (HCA). Multivariate analysis (Wilk's Λ = 0.02 × 10^-4, P < 0.01) explained the discrimination behaviour of phenolics and antioxidants by different solvents. Moreover, DA with three discrimination functions (DFs) and HCA with three well-defined clusters (clusters 1 to 3) further demonstrated the differences and/or similarities among the solvents. Solvent I (75% ethanol: water) exhibited the different extraction process over the solvents IV (water) and III (acetone: water). Quercetin (39.25 mg kg⁻¹), epicatechin (53.08 mg kg⁻¹) and gallocatechin gallate (1.28 mg kg⁻¹) were the major phenolic compounds in Kyoho skin, seed and flesh extracts, respectively. These further confirmed the chemometric approach that could be used to discriminate solvents. Therefore, these findings suggested the application of chemometrics in extraction studies to understand the role of solvents and high recovery of grape bioactive compounds.     

Nondestructive measurement of firmness and soluble solids content for apple fruit using hyperspectral scattering images

Nondestructive sensing is critical to assuring postharvest quality of apple fruit and consumer acceptance and satisfaction. The objective of this research was to use a hyperspectral scattering technique to acquire spectral scattering images from apple fruit and develop a data analysis method relating hyperspectral scattering characteristics to fruit firmness and soluble solids content (SSC). Hyperspectral scattering images were obtained from ‘Golden Delicious’ (GD) and red ‘Delicious’ (RD) apples, which were generated by a broadband beam over the spectral region between 500 nm and 1,000 nm. Mean and standard deviation spectra were extracted from the hyperspectral scattering images. A hybrid method combining the backpropagation feedforward neural network with principal component analysis was used to develop prediction models for fruit firmness and SSC. The neural network models were able to predict fruit firmness with r ² = 0.76 and the standard error of prediction (SEP) of 6.2 N for GD, and r ² = 0.55 and SEP = 6.1 N for RD. Better SSC predictions were obtained with r ² = 0.79 and 0.64 and SEP = 0.72% and 0.81% for GD and RD, respectively. Hyperspectral scattering is promising for assessing internal quality, especially the firmness, of apples. Mention of commercial products is only to provide factual information for the reader and does not imply endorsement of the US Department of Agriculture.     

Assessment of quality‐assured Tarocco orange fruit sorting rules by combined physicochemical and sensory testing

BACKGROUND: The aim of this study was to extract a sorting rule for Tarocco orange fruit from several physicochemical and sensory tests performed on a marketable lot of 399 Tarocco orange fruits. RESULTS: The elastic tension at 5% strain (T₅) was found to be linearly correlated (r = 0.65) with the Magness–Taylor (MT) index. Thus T₅ was regarded as a non‐destructive parameter quantifying fruit firmness and used to categorise the aforementioned lot in three different firmness classes, high (HF), medium (MF) and low (LF). Only the MT index, fruit rind thickness near the fruit peduncle, lightness coefficient and yellow/blue hue component of the orange flesh, as well as total soluble solid content, confirmed the validity of this discrimination at the significance level of 5%. Sensory professionals recognised the greater compactness (7 ± 2) but lower ease of peeling (4 ± 2) and segment separation (4 ± 2) of the HF oranges with respect to the corresponding sensory attributes of orange fruits grouped in the MF and LF classes. CONCLUSION: To limit the costly rejection of Tarocco orange fruit considered too soft, especially after long‐term shipping, it would be reasonable to select only fruits characterised by a compressive force or tension at 5% strain in the range 23–41 N or 300–540 N m^?1 respectively. © 2012 Society of Chemical Industry