Search Results (12)

The application of 1-methylcyclopropene (1-MCP) is widely used to extend the storage life of climacteric fruits, such as ‘Rocha’ pears. However, the suppression of ethylene’s action by 1-MCP often results in excessive ripening delay, compromising fruit quality and consumer acceptance. In this study, we investigated the potential of glyoxylic acid (GLA) to counteract the effects of 1-MCP and promote ripening. To evaluate this, ‘Rocha’ pears treated with 1-MCP were exposed to 3% (m/v) GLA and stored at 20 ± 2 °C for 15 days. Typical ripening indicators, such as firmness, skin color, ethylene production, respiration rate, volatile organic compounds (VOCs), sugars, and the activity of ethylene biosynthetic enzymes, were measured. Our results indicate that GLA did not induce significant effects on the ripening response, as ethylene production remained comparable to that of the control. Consequently, no significant changes in firmness, skin yellowing, or sugar content were observed in the GLA-treated pears. However, GLA significantly increased respiration rates (approximately 57%) and induced higher emissions of stress-associated VOCs, including hexanal, (E)-2-hexenal, and ethanol. This suggests that GLA may influence metabolic pathways related to energy metabolism and redox homeostasis without necessarily triggering ethylene-induced ripening. This study provides new insights into the interactions between GLA, 1-MCP, and fruit development, contributing to the development of alternative strategies to manage the effects of 1-MCP in ‘Rocha’ pear storage. Full article

This study aimed to evaluate the vegetative, productive, and fruit quality parameters of the European pear cultivars ‘Rocha’ and ‘Santa Maria’ under the training systems of Tall Spindle, with branches bent at an angle of 45° (Tall Spindle—45°) and 90° (Tall Spindle—90°) to the leader, and Bi-axis. The evaluation was conducted over the 2016/2017 to 2022/2023 growing seasons in the highland region of southern Brazil. Both Tall Spindle systems significantly improved the yield and productive efficiency compared to the Bi-axis system, with ‘Santa Maria’ showing superior performance under Tall Spindle—90°. While ‘Rocha’ exhibited no significant differences between Tall Spindle systems, it benefited from better vigor control and reduced biennial bearing when trained under the Bi-axis system. Fruit quality parameters were consistent across training systems, indicating Tall Spindle—90° as an optimal choice for productivity and stability in ‘Santa Maria’. These results emphasize the adaptability and efficiency of training systems for pear orchard management. Full article

Nowadays, consumers are more aware of the effects of their diet on their health, and thus demand natural or minimally processed food products. Therefore, research has focused on processes that assure safe products without jeopardizing their nutritional properties. In this context, this work aimed to evaluate the effects of high-pressure processing (550 MPa/3 min/15 °C, HPP) on a fruit salad (composed of melon juice and pieces of Golden apple and Rocha pear) throughout 35 days of storage at 4 °C. For the physicochemical properties analysed (browning degree, polyphenol oxidase activity, antioxidant activity (ABTS assay), and volatile profile), a freshly made fruit salad was used, while for the microbiological tests (total aerobic mesophiles, and yeast and moulds) spoiled melon juice was added to the fruit salad to increase the microbial load and mimic a challenge test with a high initial microbial load. It was determined that processed samples were more microbiologically stable than raw samples, as HPP enabled a reduction of almost 4-log units of both total aerobic mesophiles and yeasts and moulds, as well as an almost 1.5-fold increase in titratable acidity of the unprocessed samples compared to HPP samples. Regarding browning degree, a significant increase (p < 0.05) was observed in processed versus unprocessed samples (roughly/maximum 68%), while the addition of ascorbic acid decreased the browning of the samples by 29%. For antioxidant activity, there were no significant differences between raw and processed samples during the 35 days of storage. An increase in the activity of polyphenol oxidase immediately after processing (about 150%) was confirmed, which was generally similar or higher during storage compared with the raw samples. Regarding the volatile profile of the product, it was seen that the compounds associated with melon represented the biggest relative percentage and processed samples revealed a decrease in the relative quantity of these compounds compared to unprocessed. Broadly speaking, HPP was shown to be efficient in maintaining the stability and overall quality of the product while assuring microbial safety (by inactivating purposely inoculated microorganisms), which allows for longer shelf life (7 versus 28 days for unprocessed and processed fruit salad, respectively). Full article

Tackling human malnutrition resulting from mineral deficits in foods is currently an agro-industrial problem. To address this problem, an agronomic workflow to enrich Rocha pears with calcium (Ca) was considered in two orchards in Portugal. This study aims to assess quality differences in the irrigation water of two orchards (of Rocha pear) where an agronomic Ca enrichment workflow would be performed and identify possible conditioning to Ca increases in fruits. Thus, electrical conductivity (EC), pH, pHs, cations (Na⁺, K⁺, Ca²⁺, and Mg²⁺), and anions (HCO₃⁻, Cl⁻, and SO₄²⁻) were attained to calculate the Sodium Adsorption Ratio (SAR) index and the Langelier Saturation Index (LSI) and assess the agricultural use. The values of EC, pH, pHs, SAR index and LSI of both orchards varied between 1198 and 1211 µS/cm, 7.4 and 7.5, 7.7 and 8.1, 3.5 and 7.4, and −0.69 and −0.21, respectively. Regarding Piper classification, irrigation waters were classified as sodium bicarbonate (orchard 1) and sodium chloride bicarbonate (orchard 2). Both orchards presented different classifications regarding agricultural use, namely C3S1 (orchard 2) and C3S2 (orchard 1). The water of both orchards presented the same salinity hazard (C3), but the use of these irrigation waters is enabled since these trees can be considered salt-tolerant. However, regarding the alkalinization hazard to soils, the irrigation water from orchard 2 offers less danger (S1) in comparison to orchard 1 (S2). Meanwhile, a slightly inferior LSI (orchard 1) can favor a higher tendency to dissolve calcium carbonate. In conclusion, although slightly different, analysis indicated that the waters of both orchards did not induce toxicity in Rocha pear trees. Full article

Soil is a limited resource that is vital for plant production during the agricultural phase, and consequently, it is a fundamental component of the agro-industrial sector. In a near future, when efficiency in food production will be crucial to feed a growing population, agronomic strategies to ensure food quality need to be tested and optimized with field trials. Taking this into consideration, in 2018, as part of the execution of a fortification workflow for Rocha pears (Pyrus communis L.), field characterization was carried out before the beginning of foliar spraying to identify possible limitations to the increase in calcium in fruits. Thus, in March, soil samples were collected from an orchard (i.e., a parcel with 500 m²) located in the western region of Portugal, where this variety is largely produced. During sample analysis, humidity, organic matter, pH, electrical conductivity and colorimetric parameters were assessed using a CIELab system (with and without organic matter) and mineral analysis was assessed using X-ray fluorescence (of soils and fruits at harvest). Humidity values indicated there was even irrigation in the orchard. Additionally, it was found that organic matter values influenced soil color. The electrical conductivity and pH values were within the recommended range for pomeids. Additionally, higher values of Ca and P prevailed in soils, while K and S contents remained higher in fruits. In conclusion, no major limitations were identified, and field characterization before Ca fortification workflow was useful to assess the orchard’s conditions and possible limitations to nutrient absorption by trees. Full article

Since the prohibition of diphenylamine, replacement strategies have been needed for long-term disorder prevention, namely superficial scald (SC), in fruit. However, as this disorder only appears after months under cold storage, the assessment of effective strategies to prevent this disorder requires long periods. To tackle this challenge, we report in this paper a rapid and reliable system to induce symptoms, such as SC, based on storage under a β-farnesene-enriched atmosphere. Using this model, SC symptoms in ‘Rocha’ pear were induced after 15 d at 20 °C. As proof of concept, this model system allowed the study of the efficiency of antioxidant natural-based coatings on ‘Rocha’ pear quality maintenance. Pears treated with the coatings were submitted to 4 months of commercial storage under normal atmosphere conditions and the results were compared with those obtained using the induction model system. A PCA of chemical data allowed us to conclude that the model developed simulates the potential of certain strategies to prevent disorders. Full article

The exponential increase of the world’s population is a major concern for the food sector because the quantity and quality of food products need to be ensured for consumers. Thus, in an orchard of pears located in Portugal, a total of seven foliar sprays, using CaCl₂ and Ca(NO₃)₂, were performed; the first two sprays with three different concentrations each (CaCl₂—0.4, 0.8, and 1.6 kg·ha⁻¹; Ca(NO₃)₂—0.1, 0.3, and 0.6 kg·ha⁻¹), the third with CaCl₂ 4 kg·ha⁻¹, and the remaining four with CaCl₂ 8 kg·ha⁻¹. During the workflow, a normalized difference vegetation index (NDVI) was attained with an unmanned aerial vehicle (UAV) and was later correlated with photoassimilates synthesis (assessed by a portable open-system infrared gas analyzer) and Ca content in leaves and fruits (assessed by X-Ray fluorescence analysis). Regarding NDVI values, the exclusive use of CaCl₂ presented slightly inferior values; however, no major signs of disrupted vegetation were detected. For leaf gas exchange, only minor changes occurred (namely E and iWUE parameters), while calcium content in leaves during the workflow and fruits at harvest increased. In conclusion, smart farming techniques can be correlated with in situ analysis to monitor Rocha pear trees, and the concentrations used in this study increased Ca content in fruits without reaching toxicity levels. Full article

The objective of this research was to evaluate the effect of drying temperature and innovative pre-treatments (i.e., microwave and ultrasound) on “Rocha” pear drying behavior and quality characteristics, such as color, total phenolic content and antioxidant activity. Experiments were carried out with pear slabs subjected to microwaves (2450 MHz, 539 W, 4 min, microwave oven) and ultrasounds (35 kHz, 10 min, in an ultrasonic bath) as well as control samples. The drying process was conducted in a tray dryer at three different temperatures (50, 55 and 60 °C) and a fixed air velocity of 0.75 m/s. Microwave technology resulted in a higher quality deterioration in dried pear samples compared to those of controls and ultrasound pre-treated samples. The combined application of ultrasound pre-treatment and the higher drying temperature of 60 °C was characterized by the lowest color changes (ΔE = 3.86 ± 0.23) and higher preservation of nutritional parameters (total phenolic content, TPC = 345.60 ± 8.99; and antioxidant activity, EC₅₀ = 8.80 ± 0.34). The drying characteristics of pear fruits were also analyzed by taking into account empirical models, with the Page model presenting the best prediction of the drying behavior. In conclusion, ultrasound application is a promising technology to obtain healthy/nutritious dried “Rocha” pear snacks as dietary sources for consumers. Full article

The food industry will face determinant challenges in the future, namely, feeding a growing population, set to reach up to 9 billion people by 2050, while maintaining food quality, in circumstances of resource limitations and sustainable use. In this outlook, minimizing mineral deficits in the human diet can prevent health diseases. Calcium is one of the most abundant minerals in human organisms, performing both structural and signaling functions, its deficits being associated with the development of osteoporosis and other pathologies. To minimize this issue, foliar spraying of edible plants can increase the amount of minerals, triggering additional value in unprocessed food products. Following this assumption at an orchard of Rocha pears located in the West region of Portugal, seven foliar sprays were carried out with calcium chloride (4% corresponds to the exclusive use of CaCl₂ 4 kg ha⁻¹; 8% corresponds to the use of CaCl₂ 4 kg ha⁻¹ (for the first three sprays) and CaCl₂ 8 kg ha⁻¹ (for the four remaining sprays)). At harvest, calcium levels increased about 12.2–38.3%, whereas significant differences in physicochemical parameters occurred only in malic acid and total soluble solids. In conclusion, calcium levels increased in fruits after foliar spraying, but quality parameters only revealed minor changes, enabling the production of biofortified Rocha pears. Full article

Although new storage technologies have been emerging in recent years, preservation of pear (Pyrus communis L.) remains a challenge for suppliers. Maintenance of desired organoleptic properties throughout cold storage using non-chemical strategies has been investigated and the use of edible coatings has shown potential to delay fruit quality deterioration during cold storage. Thus, the objective of this study is to evaluate the impact of pectin coatings including plant extracts, in “Rocha” pear (Pyrus communis L. cv. Rocha) preservation. A four-month pilot scale assay was performed in both dynamic controlled atmosphere (DCA) (−0.5 °C, 0.5% O₂, and 0.4% CO₂) and normal atmospheric (NA) conditions (2 °C). For each storage condition, the following three coatings were tested: pectin (3% w/v) (PCT), pectin (3% w/v) + strawberry tree leaves extract (9.5 mg/mL) (CT1), and pectin (3% w/v) + apple pomace extract (16 mg/mL) (CT2). Volatile compounds, potentially related to aroma or ripening status of “Rocha” pear, were monitored alongside with conjugated trienols (CTs) and maturity parameters. The combination of DCA conditions and the application of pectin coatings were able to reduce the release of Rocha pear volatiles associated with ripening status, (particularly esters and sesquiterpenes), as well as reduce CTs, which could contribute to the preservation of Rocha pear for longer periods. Full article

“Pera Rocha do Oeste” is a pear (Pyrus communis L.) variety native from Portugal with a Protected Designation of Origin (PDO). To supply the world market for almost all the year, the fruits are kept under controlled storage. This study aims to identify which classical physicochemical parameters (colour, total soluble solids (TSS), pH, acidity, ripening index, firmness, vitamin C, total phenols, protein, lipids, fibre, ash, other compounds including carbohydrates, and energy) could be fingerprint markers of PDO “Pera Rocha do Oeste”. For this purpose, a data set constituting fruits from the same size, harvested from three orchards of the most representative PDO locations and stored in refrigerated conditions for 2 or 5 months at atmospheric conditions or for 5 months under a modified atmosphere, were selected. To validate the fingerprint parameters selected with the first set, an external data set was used with pears from five PDO orchards stored under different refrigerated conditions. Near infrared (NIR) spectroscopy was used as a complementary tool to assess the global variability of the samples. The lightness of the pulp; the b* CIELab coordinate of the pulp and peel; and the pulp TSS, pH, firmness, and total phenols, due to their lower variability, are proposed as fingerprint markers of this pear. Full article

The effect of coating ‘Rocha’ pears with alginate-based nanoemulsions enriched with lemongrass essential oil (LG) or citral (Cit) was investigated. Fruit were treated with the nanoemulsions: sodium alginate 2% (w/w) + citral 1% (w/w) (Cit1%); sodium alginate 2% (w/w) + citral 2% (w/w) (Cit2%); sodium alginate 2% (w/w) + lemongrass 1.25% (w/w) (LG1.25%); sodium alginate 2% (w/w) + lemongrass 2.5% (w/w) (LG2.5%). Then, fruit were stored at 0 °C and at 95% relative humidity, for six months. Fruit samples were taken after two, four and six months, and then placed at 22 °C. Upon removal and after 7 d shelf-life, fruit were evaluated for colour CIE (L*, h◦), firmness, soluble solids content (SSC), titratable acidity (TA), weight loss, electrolytic leakage, microbial growth, symptoms of superficial scald and internal browning. All nanoemulsions had droplets in the nano range <500 nm, showed uniformity of particle size and stable dispersion. Cit-nanoemulsions had lower droplet size and higher stability than LG. No nanoemulsion showed cytotoxicity. Coatings reduced fruit colour evolution and preserved better firmness than control. After shelf-life, better firmness was found in LG-coated fruit. Coatings did not affect SSC and TA. Microbial growth was below the safety limits in all treatments. Fruit treated with LG-nanoemulsions did not show scald symptoms and panelists preferred LG1.25% coated fruit. Cit2% treated fruit showed the highest scald and internal browning symptoms, while LG1.25% did not show any disorders. This study suggests that LG-nanocoatings have the potential for preserving the quality of ‘Rocha’ pear. Full article