Fresh Peaches Research Articles

Evaluating Chlorine Sanitization at Practical Concentrations for Controlling Listeria monocytogenes and Salmonella on Fresh Peaches.

Recent foodborne outbreaks and recalls involving Listeria monocytogenes and Salmonella-contaminated peaches have caused significant economic losses to the peach industry. This study evaluated the effectiveness of chlorine, a commonly used sanitizer in the fresh produce industry, against L. monocytogenes and Salmonella and its ability to control cross-contamination in fresh peaches. Peaches inoculated with L. monocytogenes or Salmonella (~6 log10 CFU/peach) were treated with 50-150 mg/L of free chlorine (FC, pH6.8) 24 h post-inoculation. The results revealed that chlorine had similar efficacy against L. monocytogenes and Salmonella on peaches (p > 0.05). A 30 s treatment at 50, 100, and 150 mg/L FC resulted in dose-dependent reductions (p < 0.05), achieving reductions of 0.88-0.92, 1.54-1.61, and 1.73-1.79 log10 CFU/peach, respectively. Extending the contact time to 2 min slightly but significantly enhanced the chlorine efficacy (p < 0.05). Additionally, a 30 s to 2 min exposure to chlorine with 50-150 mg/L FC resulted in a 1.05-1.43 log10 CFU/peach reduction in yeasts and molds. Tap water exposure led to substantial cross-contamination between inoculated and uninoculated fruits and processed water, with Salmonella exhibiting higher transfer rates than L. monocytogenes. The application of chlorine mitigated the cross-contamination of both pathogens but did not entirely prevent it. These findings offer valuable insights for the peach and other stone fruit industries to verify process controls.

Nano-modifications of edible materials using ionizing radiation for potential application in active food safety

Active food packaging films from Carboxy methyl cellulose and starch (CMC-g-Starch) reinforced with Magnesium-oxide (MgO) NPs are created and characterized. The effect of different particle sizes, MgO NPs concentrations and different gamma irradiation doses on the preparation of (CMC-g-Starch-MgO) edible nanocomposite films were investigated to determine their properties. Several analytical methods, such as swelling behavior, FT-IR, TEM, TGA, and mechanical characteristics, are represented to investigate different characteristics of the prepared (CMC-g-Starch-MgO) edible nanocomposite films. Also, the prepared (CMC-g-Starch-MgO) edible nanocomposite films and their coating were subjected to the fresh Peaches fruits. Their effect on the Peach fruits' lifespan was evaluated. The anti-microbial property of the edible (CMC-g-Starch-MgO) nanocomposite films of gram (+ve) and gram (–ve) bacteria was reported. Results represented the thermal and mechanical characteristics of (CMC-g-Starch-MgO) edible nanocomposite films, which were enhanced by γ irradiation. Also, the irradiated (CMC-g-Starch-MgO) edible nanocomposite films and their coating extend the lifespan of Peaches fruits and exhibit resistance to pathogenic microorganisms. In conclusion, (CMC-g-Starch-MgO) edible nanocomposite films fulfilled the required behaviors for the application in the nanofood packaging era.

The Effect of Packaging Types on Fresh Peaches in the Direct‐To‐Consumer Environment: Distribution Testing, Life Cycle Assessment and Economic Impact

ABSTRACTThe direct‐to‐consumer (D2C) shipping mode presents new opportunity for fresh peach sales in North America where demand over the past four decades has steadily declined. The hazards in this distribution mode are severe, and fresh peaches are fragile emphasizing the need for proper protection. A full analysis that not only encompasses the effects of the D2C distribution environment but also incorporates analyses of the environmental and economic impact of the packages utilized for transit of peaches is necessary. In this study, we use the metrics of peach grade, firmness, soluble solids concentration and percent softness before and after the distribution simulation to compare the protective performance of six DTC packaging systems. All six packages consist of a single layer corrugated box with varying primary packaging. A life cycle analysis of each package system is performed as well as an economic analysis on the packaged materials and cost to ship. We conclude that peach damage in shock testing is related to the freedom of movement that peaches have within each package type and varies by package system. All the package types evaluated amplify input vibration in the frequency range commonly associated with the input from the tires of truck‐trailer systems. There are no statistical differences between package systems in the distribution simulation of the six package types except in peach softness and grade of melting flesh peaches. Finally, we found that a reduction in material use and change in format, that is, foam sheets to foam netting, provides for sufficient peach protection while reducing environmental and economic impact.

Recent Approaches to the Formulation, Uses, and Impact of Edible Coatings on Fresh Peach Fruit.

Peaches are among the most well-known fruits in the world due to their appealing taste and high nutritional value. Peach fruit, on the other hand, has a variety of postharvest quality issues like chilling injury symptoms, internal breakdown, weight loss, decay, shriveling, and over-ripeness, which makes a challenging environment for industries and researchers to develop sophisticated strategies for fruit quality preservation and extending shelf life. All over the world, consumers prefer excellent-quality, high-nutritional-value, and long-lasting fresh fruits that are free of chemicals. An eco-friendly solution to this issue is the coating and filming of fresh produce with natural edible materials. The edible coating utilization eliminates the adulteration risk, presents fruit hygienically, and improves aesthetics. Coatings are used in a way that combines food chemistry and preservation technology. This review, therefore, examines a variety of natural coatings (proteins, lipids, polysaccharides, and composite) and their effects on the quality aspects of fresh peach fruit, as well as their advantages and mode of action. From this useful information, the processors could benefit in choosing the suitable edible coating material for a variety of fresh peach fruits and their application on a commercial scale. In addition, prospects of the application of natural coatings on peach fruit and gaps observed in the literature are identified.

Control of Brown Rot Produced by Monilinia fructicola in Peaches Using a Full-Spectrum Extract of Zuccagnia punctata Cav.

Brown rot of stone fruit, caused by Monilinia spp., is one of the most important diseases worldwide, causing significant production losses. Currently, the standard practices for controlling this infection consist of repetitive use of synthetic fungicides. The global tendency encourages the demand for high-quality food products harmless to health and the environment, leading to a reduction in the use of these types of substances. Zuccagnia punctata (Fabaceae) is a perennial shrub extensively used for the treatment of fungal and bacterial infections in Argentinean traditional medicine. In this study, we isolated and characterized (morphologically and molecularly) a pathogenic and virulent strain of Monilinia fructicola, which is the most hostile species of the genus. Consequently, we explored the in vitro antifungal activity of the ethanolic extract of Z. punctata against this phytopathogen. The chalcones 2′,4′-dihydroxy-3′-methoxychalcone and 2′,4′-dihydroxychalcone were isolated from the extract and evaluated against M. fructicola demonstrating that they were responsible for this activity. To promote full-spectrum extract rather than pure compounds, we performed ex-vivo assays using fresh peaches inoculated with the pathogen, and then treated by immersion in an extract solution of 250 µg/mL concentration. Treatment with Z. punctata extract did not show a statistically significant difference from commercial fungicides in the control of fruit rot. In addition, Huh7 cell cytotoxicity evaluation showed that Z. punctata extract was less cytotoxic than commercial fungicides at the assayed concentrations. Based on our research, this plant extract could potentially offer a safer alternative to commercial fungicides for treating peach brown rot.

Research on Defect Detection in Kubo Peach Based on Hyperspectral Imaging Technology Combined with CARS-MIV-GA-SVM Method.

Due to the dark red surface of ripe fresh peaches, their internal injury defects cannot be detected using the naked eye and conventional images. The rapid and accurate detection of fresh peach defects can improve the efficiency of fresh peach classification. The goal of this paper was to develop a nondestructive approach to simultaneously detecting internal injury defects and external injuries in fresh peaches. First, we collected spectral data from 347 Kubo peach samples using hyperspectral imaging technology (900-1700 nm) and carried out pretreatment. Four methods (the competitive adaptive reweighting algorithm (CARS), the combination of CARS and the average influence value algorithm (CARS-MIV), the combination of CARS and the successive projections algorithm (CARS-SPA), and the combination of CARS and uninformative variable elimination (CARS-UVE)) were used to extract the characteristic wavelength. Based on the characteristic wavelength extracted using the above methods, a genetic algorithm optimization support vector machine (GA-SVM) model and a least-squares support vector machine (LS-SVM) model were used to establish classification models. The results show that the combination of CARS and other feature wavelength extraction methods can effectively improve the prediction accuracy of the model when the number of wavelengths is small. Among them, the discriminant accuracy of the CARS-MIV-GA-SVM model reaches 93.15%. In summary, hyperspectral imaging technology can accomplish the accurate detection of Kubo peaches defects, and provides feasible ideas for the automatic classification of Kubo peaches.

Identification of volatile organic compounds as markers to detect Monilinia fructicola infection in fresh peaches

Monilinia spp. are among the main fungal pathogen affecting peaches, and they can cause severe pre- and postharvest losses. Development of smart packaging technologies (e.g., volatile indicators), facilitating infection detection and preventing other fruit from being contaminated, is still limited. In this study, we compared for the first time the aroma profile of whole healthy fresh peaches to Monilinia fructicola-artificially inoculated peaches, identifying discriminant volatile organic compounds (VOCs). More than one hundred VOCs were detected by applying head space solid-phase microextraction followed by GC-MS analysis. The level of methyl esters, hydrocarbons, lactones, and acids decreased in infected peaches indicating fruit aroma deterioration, while the concentration of ethyl esters and alcohols increased. In particular, the amount of ethanol and derived ethyl acetate reached a maximum of 24- and 20-fold increase in the infected peaches, respectively. Isobutanol, propyl acetate, and ethyl isovalerate were specifically emitted by M. fructicola-infected peaches. These compounds might serve as markers for the development of smart sensors allowing the detection of fungal infection.

Sensitisation to peach allergen Pru p 7 is associated with severe clinical symptoms in a Spanish population.

Pru p 7 has been reported as a major allergen in peach allergy, associated with severe clinical symptoms and related to IgE sensitisation to cypress pollen. The main objective of this study was to prospectively evaluate the frequency of sensitisation to Pru p 7 and its clinical relevance amongst pediatric patients with peach allergy in Madrid (Spain). Patients with a history of IgE-mediated symptoms (oral allergy syndrome, urticaria/angioedema, rhinoconjunctivitis/asthma, gastrointestinal symptoms, or anaphylaxis) occurring within 2 h after peach intake or contact were prospectively recruited from February 2020 to September 2021. Skin tests, sIgE by ImmunoCAP® (Pru p 1, Pru p 3, Pru p 4, Pru p 7, and Cupressus arizonica) and oral food challenge (OFC) were performed. The study was approved by the local Ethics Committee (PI-4513). Ninety-two patients were included (53.3% male); median age, 10 (IQR 6.0-14.75) years. Seventy-four (80.4%) patients had a reaction after ingestion of fresh peach (25.0% from peel, 23.9% from pulp, and 44.6% from both). Fifteen (16.3%) patients were sensitised to Pru p 7. Upper airway symptoms, anaphylaxis, and grade 2 reactions were statistically more frequent in patients sensitised to Pru p 7. Seven (7.9%) patients presented with exercise as a cofactor, four of whom were sensitised to Pru p 7 (p = .001). Patients sensitised to Pru p 7 were significantly more likely to have a positive OFC result than patients who were not (p = .008). Four patients who reacted to peach at OFC were sensitised to Pru p 7. Specific IgE against Cupressus arizonica pollen was positive in 25 (62.5%) patients. Pru p 7 sensitisation was observed in 16.3% of our population and was related to severe reactions, upper airway symptoms, anaphylaxis, and the presence of an eliciting cofactor.

Mycotoxin Determination in Peaches and Peach Products with a Modified QuEChERS Extraction Procedure Coupled with UPLC-MS/MS Analysis.

Peaches are the most significant temperate fruit crop worldwide. However, peach fruits are susceptible to fungal and mycotoxin contamination. Consequently, monitoring the residual levels of multiple mycotoxins in peaches and related products is essential. In this study, a novel method based on QuEChERS extraction, followed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) detection, was developed for analyzing 14 mycotoxins in peaches and peach products from China. Matrix-matched calibrations were employed to accurately quantify the mycotoxins and compensate for matrix effects. Recoveries for the target analytes ranged from 84.6% to 117.6%, with intra-day and inter-day precision below 20%. The limits of quantification were 2 or 5 μg/L for the 14 mycotoxins. This method was utilized to detect the presence of target mycotoxins in 109 fresh peaches, 100 diseased peaches, and 89 peach products from China. Six mycotoxins were identified in the rotten parts of the diseased peaches, with concentrations ranging from 5.2 to 1664.3 µg/kg. In the remaining parts of the diseased peach samples, only two toxins, alternariol (AOH) and alternariol monomethyl ether (AME), were quantified at levels of 15.3 µg/kg and 15.5 µg/kg, respectively. No mycotoxins were detected in fresh peaches. For peach products, all contamination levels were below the quantitative limits and significantly lower than the maximum legal limits established for the products.

Physicochemical and Sensory Parameters of Vegan Water Kefir Beverages Fermented with Different Fruits

Fermented foods have drawn the attention of the consumers due to their health advantages particularly after Covid-19 pandemic. Water kefir is one of these fermented foods which is produced by fermenting water-based solution containing sugar source, fruits and/or vegetables with water kefir grains. It is a slightly fizzy and sour beverage with low sugar fruity taste satisfying the needs of consumers who are vegan or having lactose intolerance/sensitivity. Although there are many fruit/vegetable alternatives that can be used in water kefir, figs are stated to be the most used and popularity is not understood fully. Therefore, in this study water kefir was produced with different fruits, namely fig, apricot, peach, mulberry and grapes and the effects on physicochemical properties during fermentation of 3 days were studied. Sensory analysis of beverages made with both dried and fresh peach, apricot and grapes was carried out to see the impact of the use of dried form. pH decreased for all samples and brix increased for all beverages except the one prepared with dried mulberry. L* value increased, b* value decreased for all samples and a* value decreased for the samples with dried figs, dried peach, dried grapes and fresh peach, increased for the one fermented with fresh grapes and remained same for the other beverages. Water kefir drinks made with fresh grapes, dried peach and dried apricot had the top three scores for color; samples with fresh grapes, dried peach and fresh apricot had the top three scores for smell; beverages with dried grapes, fresh grapes and fresh apricot had the top three scores for mouthfeel; samples with fresh and dried grapes and fresh apricot had the top three scores for taste; kefirs with fresh and dried grapes and fresh apricot had the top three scores for carbonation and water kefirs prepared with fresh fruits had the highest rankings for preference.

Microbial load on fresh peaches and hand gloves collected from selected packing facilities in Georgia

Duplicate peach samples were collected from the dumping and weighing areas of four fresh peach packing lines in Georgia at 0, 3, and 6 h into the packing process on 3 random packing days per operation in the summers of 2018 and 2019, along with duplicate glove samples from peach sorters and packers at the manual sorting and weighing areas. The samples were analyzed for the population of total aerobes (TA), total yeasts and molds (YM), and total coliforms (TC), as well as the incidence of thermotolerance coliforms (TTC) and Enterococci (EC). Not affected by sampling time, peach samples from the weighing area had significantly higher (P < 0.05) TA, YM, and TC counts and >5 or 3 times higher incidence of TTC or EC than those from the dumping area. The counts of TA, YM, and TC on hand gloves from peach sorters and packers were similar, but they were significantly higher at the 3 and 6 h sampling points than at the 0 h sampling point. Among analyzed glove samples, 39.39% and 7.58% tested positive for TTC or EC. Thus, packing line hygiene and hand gloves worn by peach handlers could be possible sources of fresh peach contamination.

A content analysis of website marketing for cooling flavored e-liquids in a sample of brick-and-mortar vape shops in the Greater Los Angeles area.

INTRODUCTIONMenthol is a characterizing flavor in combustible cigarettes and electronic nicotine delivery systems (ENDS). E-liquids are recognized as an important reason for ENDS use. Yet, compared to menthol cigarettes, menthol flavored e-liquids and other cooling flavors, including mint and ‘ice’ for ENDS, are an understudied area of investigation. The present study examined cooling flavored e-liquid website marketing among brick-and-mortar vape shops in Greater Los Angeles Area.METHODSA total of 104 brick-and-mortar vape shops were identified, and 38 had active websites. Over a 30-day period (28 September – 28 October 2020), we collected marketing for all flavored refillable e-liquids (photos/images) from each website. Data were collected for 1330 products. Only refillable e-liquid bottles were selected for this study, excluding prefilled pod vapes and disposable vapes. Each e-liquid per website was coded (e.g. menthol or not) and grouped into categories (e.g. type of menthol). The three flavor descriptor categories that the e-liquids were grouped into were menthol, mint, or ice. An ‘other’ category was also created for identified e-liquids with flavor descriptors that did not mention menthol, mint, or ice.RESULTSA total of 1330 e-liquid flavors were identified from 38 active websites. Among them, 219 were coded as menthol/mint/ice flavor e-liquids. Frequencies included ice/iced/icy (n=123; 56%), menthol (n=32; 15%), mint (n=23; 11%), and other (n=41; 19%). Of the 123 ice-flavor e-liquids, 70.3% (n=83) were in combination with fruit (e.g. ‘Apple Ice’, ‘Grape Iced’, ‘Icy Mango’). Of the 32 menthol-flavored e-liquids, 63.3% (n=19) were in combination with fruit (e.g. ‘Dragon Fruit Menthol’, ‘Blue Raspberry Menthol’, ‘Fresh Peach Menthol’). Flavors in the other category were ice-related flavor descriptors (e.g. ‘Arctic Air’, ‘Brain Freeze’, ‘Frozen Hulk Tears’).CONCLUSIONSBrick-and-mortar vape shops in the Greater Los Angeles Area market a variety of cooling flavor e-liquids on their websites. Such marketing focused largely on ice fruit flavor combinations. Future research is needed to understand how exposure to and appeal of cooling flavored e-liquid marketing differs among diverse consumer groups, including adult menthol cigarette smokers and non-smoking youth.

Prediction of Potassium in Peach Leaves Using Hyperspectral Imaging and Multivariate Analysis

Hyperspectral imaging (HSI) is an emerging technology being utilized in agriculture. This system could be used to monitor the overall health of plants or in pest/disease detection. As sensing technology advancement expands, measuring nutrient levels and disease detection also progresses. This study aimed to predict three different levels of potassium (K) concentration in peach leaves using principal component analysis (PCA) and develop models for predicting the K concentration of a peach leaf using a hyperspectral imaging technique. Hyperspectral images were acquired from a randomly selected fresh peach leaf from multiple trees over the spectral region between 500 and 900 nm. Leaves were collected from trees with varying potassium levels of high (2.7~3.2%), medium (2.0~2.6%), and low (1.3~1.9%). Four pretreatment methods (multiplicative scatter effect (MSC), Savitzky–Golay first derivative, Savitzky–Golay second derivative, and standard normal variate (SNV)) were applied to the raw data and partial least square (PLS) was used to develop a model for each of the pretreatments. The R2 values for each pretreatment method were 0.8099, 0.6723, 0.5586, and 0.8446, respectively. The SNV prediction model has the highest accuracy and was used to predict the K nutrient using the validation data. The result showed a slightly lower R2 = 0.8101 compared with the training. This study showed that HSI could measure K concentration in peach tree cultivars.

Starch/PBAT blown antimicrobial films based on the synergistic effects of two commercial antimicrobial peptides

In this study, starch/PBAT antimicrobial film, based on the synergistic effects of two commercial antimicrobial peptides, was fabricated by blown extrusion. The blends with nisin exhibited higher storage modulus and complex viscosity than those with ε-polylysine hydrochloride (ε-PL) alone. ATR-FTIR spectra revealed that new intermolecular hydrogen bonds were formed among starch, nisin, and ε-PL. XRD results indicated that antimicrobial peptides facilitated the destruction of the original crystalline structure of starch. Combination of ε-PL and nisin enhanced tensile strength, flexibility, moisture permeability, and oxygen barrier property of the films with more homogeneous morphology. SP-PN1/2 film (1% ε-PL + 2% nisin) exhibited over 90% inhibition rates against Staphylococcus aureus and Escherichia coli, and prolonged the shelf life of fresh peaches. The antimicrobial film with nisin and ε-PL showed high safety, cost-effectiveness, consumer acceptability, and thus it had a good application prospect in the food packaging field.

Flower and fruit development of a low-chill peach, ‘KU-PP2’ in plastic houses with and without heating

Although ‘KU-PP2’, a low-chill peach cultivar, was released for high-quality peach production under forcing culture, the performance of ‘KU-PP2’ trees under forcing conditions has yet to be determined. In this study, we investigated the spring phenology, fruit development, and fruit quality of ‘KU-PP2’ in a heated plastic house compared with the same traits in an unheated plastic house and open field conditions. We found that the forcing conditions accelerated the spring phenology and harvest period of ‘KU-PP2’. Heated conditions shortened the number of days from dormancy release to blooming and the length of the fruit development period, resulting in the blooming of flowers in late February, with fruit begin harvested as early as mid-May, which was notably earlier than blooming and fruit harvest under natural conditions by 4 and 6 weeks, respectively. Similarly, the unheated conditions accelerated the time to blooming and harvest by up to 3 and 4 weeks, respectively compared with the open field conditions. However, although the fruit produced by trees raised in the heated plastic house could be harvested at an earlier date, the amount of fuel used for the heating system was 50 L per tree, which could be prohibitively expensive for commercial production. Although the fruit growth pattern did not differ significantly between the forcing and natural conditions, the rate of fruit growth at stages S1 and S2 was higher in the heated plastic house than that under the other assessed conditions. Furthermore, the size and quality of fruit obtained under forcing conditions were slightly larger and superior, respectively, than those of fruit produced under natural conditions. Moreover, we found no evidence of split-pits under the forcing conditions. The findings of this study accordingly indicate that cultivation of the low-chill peach ‘KU-PP2’ under forcing conditions is conducive to a notably earlier harvest of fresh peaches. These observations advance our current understanding of the flowering, fruit development, and fruit production of low-chill peaches under forcing conditions.

CULTURE MEDIA EVALUATION ON THE Leucoagaricus gongylophorus AND Escovopsis sp. FUNGI DEVELOPMENT

This study aimed to evaluate the in vitro interference of different culture media, Czapek Dox Agar, Nutrient Agar, Starch Casein agar, Malt Extract Broth Base, Nutrient Broth, and the medium containing Peptone, Malt, Agar and crushed peach palm pulp (Bactris gasipaes) and tucumã (Astrocaryum aculeatum) on the fungus Leucoagaricus gongylophorus and the parasitic fungus Escovopsis sp. growth. The fungi were inoculated in different culture media and then kept in acclimatized chambers at 28 ºC in the dark for 42 days, being analyzed at weekly intervals, totaling six evaluations. Fungal colonies were evaluated considering the factor "f" (cm), obtained from the product between the width (W) and length (L) of the diameter of the colonies (f = W x L). The results showed that the symbiotic fungus and the leafcutter ant parasitic fungus showed a growth increase compared to the media provided in the plates, and the media added with tucumã peel, tucumã peel+pulp, fresh peach palm, and cooked peach palm had a significant effect in the L. gongylophorus fungus development. However, these treatments were not promising for the Escovopsis sp. fungus compared to other culture media.

Development of an artificial neural network as a tool for predicting the chemical attributes of fresh peach fruits.

This investigation aimed to develop a method to predict the total soluble solids (TSS), titratable acidity, TSS/titratable acidity, vitamin C, anthocyanin, and total carotenoids contents using surface color values (L*, Hue and chroma), single fruit weight, juice volume, and sphericity percent of fresh peach fruit. Multiple regression analysis (MLR) and an artificial neural network (ANN) were employed. An ANN model was developed with six inputs and 15 neurons in the first hidden layer for the prediction of six chemical composition parameters. The results confirmed that the ANN model R2 = 974–0.998 outperformed the MLR models R2 = 0.473–0.840 using testing dataset. Moreover, sensitivity analysis revealed that the juice volume was the most dominating parameter for the prediction of titratable acidity, TSS/titratable acidity and vitamin C with corresponding contribution values of 39.97%, 50.40%, and 33.08%, respectively. In addition, sphericity percent contributed by 23.70% to anthocyanin and by 24.08% to total carotenoids. Furthermore, hue on TSS prediction was the highest compared with the other parameters, with a contribution percentage of 20.86%. Chroma contributed by different values to all variables in the range of 5.29% to 19.39%. Furthermore, fruit weight contributed by different values to all variables in the range of 16.67% to 23.48%. The ANN prediction method denotes a promising methodology to estimate targeted chemical composition levels of fresh peach fruits. The information of peach quality reported in this investigation can be used as a baseline for understanding and further examining peach fruit quality.

The Influence of Product Quality on Export Performance: Eco-Efficient Value in South African Peach and Nectarine Fresh Exports

This study evaluates the role of quality in influencing export earnings. It argues that different types of product attributes confer different quality features and these features provide diverse consumer value which influence the export product’s market performance. The gravity model is used to regress export earnings against indices measuring product value propositions, as well as economic, demographic, demand and trade regulation indicators. It uses data from South Africa’s fresh peach and nectarine exports and 21 trading partners for the period between 2001 and 2017. The study’s results show that improvements in the delivery of esthetic quality were associated with increases in export earnings. On the other hand, improvements in eco-efficiency (sustainable production and consumption) and the delivery off-season fruit were associated with lower export earnings. The results reiterate the importance of providing consumer value, the provision of communication for any additional environmental quality-upgrades and consensus in quality definitions with importing countries.

Efficacy of commercial overhead washing and waxing systems on the microbiological quality of fresh peaches

Overhead spray washing and waxing systems (WWS) are used commercially to reduce the risk of microbial contamination and improve the quality of fresh produce during packing. This study evaluated the microbiological quality of overhead spray water and spent peach wash water, as well as fresh peaches before and after they pass the WWS. Pre- and post-washed/waxed peach samples (n = 192) and overhead spray water and spent peach wash water samples (n = 54) were collected several times over the course of a processing day in three packing facilities located in the state of Georgia. Populations of total aerobes (TA), yeasts and molds (YM), and coliforms (TC) and the presence of thermotolerant coliforms (TTC) and enterococci (EC) were measured in collected samples. The average TA and TC counts and the incidences of TTC and EC were significantly higher (P < 0.05) on peach samples collected after the WWS compared to those collected before the WWS. Counts and incidences of TA, YM, and TC in spent peach wash water were significantly higher than in the overhead spray water where neither TTC nor EC was detected. Results suggest that the commercial washing and waxing systems had little effect in improving the microbiological quality of fresh peaches.

Thin Layer Peach Drying in Solar Tunnel Drier

This study presents performance of the solar tunnel dryer for drying of peach samples. The solar tunnel dryer consists of a flat plate solar collector, a drying tunnel, a solar cell module and a small axial fan. It has been constructed at the Department of Agricultural Machinery and Technologies Engineering at Isparta University of Applied Sciences. During the drying process, solar irradiation, drying air temperature, relative humidity, and air velocity were measured constantly in different parts of the dryer. At same time, mass loss of the peach samples was measured during the drying period at one-hour interval. In this study, the color measurements fresh and dried products were determined at the beginning and end of experiment. The fresh peach samples were sorted, graded, washed by tap water and then sliced manually as half-moon without peeling before pretreatment. Sun drying behavior of sliced peach samples pretreated with 1% sodium metabisulfit, 1% ascorbic acid and non-pretreated was investigated. The drying characteristic curves were evaluated against ten mathematical models. Results showed that the Midilli et al. model was found to be the best descriptive model for solar tunnel drying of thin layer peach.