Pomegranate Fruit Quality Research Articles

BIOCHEMICAL CHARACTERIZATION AND EFFECT OF BACTERIAL BLIGHT ON MICRO AND MACRO NUTRIENT CONCENTRATION IN POMEGRANATE

Bacterial blight is a serious disease of pomegranate. The disease affects the yield and quality of pomegranate fruits. In this present work, we investigated the biochemical characterization and role of micro and macro nutrients in diseased and healthy leaves of pomegranate. Pathogen was isolated infected leaves, twigs and fruits and grown on different culture media. Different biochemical tests (Gram staining, KOH, catalase, oxidase, starch hydrolysis, gelatin liquefaction) were performed to identify the bacteria. All these tests confirm the presence of Xanthomonas axonopodis pv punicae. Pathogenicity was done in the greenhouse using three different methods (Pin-pricked, infiltration and spray method) and symptoms appeared in 8 days; and infiltration method showed early symptoms compared to the spray and pin prick method. Ionic contents (Nitrogen, Potassium, Phosphorus, Magnesium, Calcium, Iron, Boron, Zinc and Copper) are reduced by using these nutrients for the growth, multiplication and survival of pathogenic bacteria. Proper application of these nutrients helps the host plant to improve its physiological and biochemical development and resistance to bacterial blight disease in pomegranate.

Effects of different irrigation regimes on vegetative growth, yield and fruit quality of young pomegranate (Punica granatum ‘Wonderful’) trees

ISHS IX International Symposium on Irrigation of Horticultural Crops Effects of different irrigation regimes on vegetative growth, yield and fruit quality of young pomegranate (Punica granatum ‘Wonderful’) trees

Timing and Rate of Foliar Potassium Application to Improve Yield, Fruit Size and Quality Attributes of Pomegranate: Based on Data Generated in Field Experiments Conducted in Iran and Egypt

ABSTRACT It is proven that potassium (K) plays a key regulatory role in many physiological processes of plant growth and that K fertilization can improve the yield and quality attributes in fruit crops. This study was carried out to evaluate the effect of timing and various concentrations of foliar sprays of potassium sulfate, during fruit growth and maturation, on yield and quality of pomegranate fruit in Iran and Egypt, which have different pomegranate production systems. In Iran one, two or three sprays of 1% or 2% K-Leaf® (a high grade foliar potash booster) was used, and in Egypt a single spray of either 10 or 20 kg/ha, and two sprays of 10 and 20 kg/ha K-Leaf® were applied. Results showed that in both experiments in Iran and Egypt, foliar K treatments increased total and marketable yield of pomegranates, as well as fruit weight and size, flavor index (the ratio of total soluble solids/total acid). The treatments also improved the fruit’s peel and aril color compared to the non-treated control plants. Results also demonstrated that multiple potassium sprays (two or three applications) were more effective than applying higher concentrations; as in many cases, there were no significant differences between 1 and 2% concentrations of K fertilizer in treatments with same number of applications (one, two or three sprays). Although three sprays of 2% K-Leaf® were the most effective treatments, it can be concluded that three sprays of 1% K-Leaf®) is probably more economically sound for use in pomegranate orchards.

Ameliorative effect of melatonin against storage chilling injury in pomegranate husk and arils through promoting the antioxidant system

Pomegranate is a tropical and subtropical fruit sensitive to chilling injury during its cold storage, leading to quantitative and qualitative losses, as well as reduced economic value. Recently, melatonin has been considered as an environmentally friendly treatment to maintain the postharvest quality of horticultural products. In this study, the effect of melatonin treatment on chilling tolerance, postharvest quality and antioxidant system of pomegranate fruit was investigated during storage at 4 °C for 120 days. According to the results, pH, titratable acidity and the total soluble solids of the fruit were not influenced by applying melatonin. However, melatonin treatment at 100 μM dramatically improved chilling tolerance in the pomegranate fruit by reducing electrolyte leakage and increasing the total phenol content, as well as the antioxidant potential. Melatonin significantly reduced polyphenol oxidase (PPO) activity and increased the activity of phenyl alanine amylase (PAL), catalase (CAT), ascorbate peroxidase (APX) and superoxide dismutase (SOD) enzymes in the husk and arils of the pomegranate fruit during storage. In addition, melatonin inhibited H2O2 accumulation in the pomegranate fruits. Therefore, our data suggest that melatonin might be useful in improving the postharvest quality and inducing chilling tolerance in pomegranates during the cold storage.

Impact of biofertilizers and organic manures on growth, fruit quality and leaf nutrient status of pomegranate in LONI (MS) INDIA

The study was conducted to investigate the effect of organic manures and biofertilizers on the vegetative growth, fruit quality and leaf nutrient status of pomegranate. The treatments consisted of the application of vermicompost, Azotobacter, Azospirillum, phosphorous solubilising bacteria (PSB)and farm yard manure (FYM) in different doses and combinations along with a control in which only organic fertilizers were applied. Combined application of vermi compost (15kg/Plant) + Azospirillum@ 150 g/tree + PSB @150 g/tree resulted in maximum plant height, canopy spread, trunk girth, fruit weight, while maintaining yield at par with inorganic fertilizers treatment. Maximum leaf P and K contents were recorded in treatment consisting of vermicompost (15kg/ plant) + Azospirillum @ 100 g/tree + PSB @100 g/tree but maximum leaf N content was recorded under FYM (15 kg/ plant) + Azospirillum @ 150 g/tree + PSB @150 g/tree. Use of biofertilizers with organic manures was found to be a good approach for production of quality pomegranate fruits without compromising the yield.

Multi-Spectral Imaging for Fruits and Vegetables

In the field of agriculture, fruit grading and veg-etable classification is an important and challenging task. The current fruit and vegetable classifications are done manually, which results in inconsistent performance. There is an influence of external surroundings on this manual classification. Sometimes getting an expert fruit or vegetable grader, is challenging and the performance of that person may become stagnant over some time. With the recent development in computer technology and multi-spectral camera system, it is possible to achieve an efficient fruit grading or vegetable classification system. In this manuscript, we summarize different automated fruit grading as well as vegetable classification systems, which are based on multi-spectral imaging. We have focused our analysis on four major areas such as varietal identification, fruit quality assessment, classification, and disease detection. From our analysis, we have found that the Partial Least Square Discriminant Analysis (PLS-DA) was most effective for identifying varieties of tomato seeds. For analyzing the quality of pomegranate fruits, the multiple linear regression model was the most optimal method. Multi-Layer Perceptron (MLP) classifier was the recommended method for classifying medicinal plant leaves. A Linear Discriminant Analysis (LDA) based classifier could accurately detect diseases in fruits and vegetables.

Pomegranate Fruit Quality and Seed Drying Method: Effect on the Chemical Composition and Bioactivities of the Extracted Oil

The study presents a comparative investigation of the composition and bioactivity of oil extracted from pomegranate seeds of sun-burned fruit (SB) and healthy fruit (HF) for the value-adding potential of pomegranate fruit waste. Seeds from SB and HF were independently freeze dried, sun dried, and oven dried before ultrasound-assisted oil extraction using petroleum ether. The extracted oil was analysed for yield, refractive index, ρ-anisidine value, total phenolic content (TPC), DPPH radical scavenging ability, antimicrobial activity, tyrosinase enzyme inhibition ability, and fatty acid composition. The results showed that oven dried seeds, regardless of fruit quality, yielded the highest oil (20.85–24.70%, dry weight). Regardless of the seed drying method, oil from the seeds of SB exhibited the highest TPC (1.48–2.84 mgGAE/g PSO) than oil from the seeds of HF. The oil from oven dried and freeze dried seeds of SB were more effective in scavenging the DPPH radicals with IC50 values of 34.77 and 39.97 µg/mL, respectively. All the oil samples showed good ability to inhibit tyrosinase enzyme regardless of fruit quality and seed drying method, with monophenolase and diphenolase IC50 ranging between 0.31 and 0.49 mg/mL and 0.64 and 2.43 mg/mL, respectively. Irrespective of the drying method, oil extracted from HF seeds exhibited greater antimicrobial potency against the tested bacteria. The fatty acid composition of the oil samples was neither affected by fruit quality and seed drying method. Generally, all oil samples exhibited high levels of punicic acid (81.21–82.68%) and low omega 6 to omega 3 ratios (0.19–0.37%), suggesting that the oil samples were healthy. Principal component analysis (PCA) established that freeze dried seeds of SB is an excellent source of oil with higher TPC, punicic acid, polyunsaturated fatty acids, and unsaturated fatty acid/saturated fatty acid ratio. It can be concluded that the seed from SB is a good raw material for oil that can be utilised in cosmetic products formulation.

CONTROLLING OF FRUIT SPLITTING IN POMEGRANATE (PUNICA GRANATUM L.) BY FOLIAR APPLICATION OF GROWTH REGULATOR AND NUTRIENTS

Various growth regulators have been used to improve the quality of different fruit crops. Foliar spray of macro and micronutrients play an important role in vegetative growth, yield and fruit quality. In the present study, the influence of foliar application of growth regulators and nutrients on fruit splitting and fruit quality was evaluated. For that purpose, Naphthaleneacetic acid (NAA), Potassium nitrate (KNO3) and Boric acid (H3BO3) at the rate of 40 ppm, 1% and 0.3% were used respectively. Spray of chemicals were applied in 2nd and 8th week from full bloom to yield in pomegranate cultivar ‘Golden pearl’. The experiment was designed under Randomized Complete Block Design (RCBD) comprised with seven treatments and replicated thrice. Fruit splitting was reduced (48.68%) significantly with application of KNO3 + Boric acid, while maximum fruit size (60.26 cm2), fruit weight (84gm), fruit grain weight (136.38gm), total soluble solid (TSS) 12.52% and yield (21.9kg/plant) were observed in KNO3 + Boric acid. Moreover, peel weight was increased in control (60.66 gm) and minimum was observed in 48.62 gm in KNO3 + Boric acid. Finally, it is concluded KNO3 %+ Boric acid reveled best results against fruit splitting % and other fruit quality parameters. These findings show that application of KNO3+ Boric acid significantly influences fruit quality of pomegranate when fruit are in the beginning stages of growth and development.

Impact of Hot Water and Modified Atmosphere Packaging Treatments on the Postharvest Quality of Pomegranate Fruit cv. Hicaznar

Hot water (HW) and modified atmosphere packaging (MAP) treatments were evaluated to maintain postharvest quality of pomegranate fruit (Punica granatum cv. ‘Hicaznar’). Pomegranates were subjected to hot water (HW) treatment (at 50 °C for 3 min) and packaged with or without MAP bags. Fruit was then kept at 6 °C for 6 months and at 20 °C for 7 days after cold storage period. The untreated and unpackaged fruit was served as a control treatment (C). MAP and HW+MAP treatments was more effective in reducing weight loss, fungal decay and husk scald, compared to HW and C treatments. The lightness and red color intensity of husk and aril (higher values of L* and C* and lower values of h°) were maintained better in the packaged fruit with MAP (MAP + HW+MAP treatments). The unpackaged fruit from HW and C treatments became unmarketable while those from MAP and HW+MAP treatments were still marketable after 6 months of cold storage and shelf life period. Although fungal decay incidence was low in HW-treated fruit, relatively high scald incidence and weight loss had adverse effect on overall visual acceptability of HW-treated fruit. Hot water dipped pomegranate fruit cv. ‘Hicaznar’ (50 °C for 3 min) could be kept in MAP bags for 6 months at 6 °C and for 7 days 20 °C without adverse effect on quality.

​Effect of Different Post-harvest Treatments of Fungicides, Botanical Oils, Food Preservatives and Packaging on Black Mould Fruit Rot of Pomegranate

Background: Pomegranate is an important favourite fruit of tropical, subtropical and arid regions. In India, it is grown in almost all the states but a commercial orchard exists in Maharashtra and Gujarat. Some pathogens only attack the fruit from the inside, while the external surface of the fruit remains asymptomatic. Diseased fruit display poor shelf life and flavour quality attributes. Changes include losses in sugars, acids, characteristic aroma and development of off flavours. Therefore, identifying and quick characterization of these disease symptoms is paramount to their effective control and management. Since there is a lack of research work on pomegranate black mould fruit rot diseases caused by Aspergillus niger. Realizing the gaps concerns the environmental factors affecting the prevalence of disease development and management of disease, the present investigation was undertaken with the objective: Management of post-harvest black mould fruit rot diseases of pomegranate by different methods. Methods: The experiments were carried out at Division of Horticulture, UAS, GKVK, Bengaluru by using the variety Bhagwa with 11 treatments which are replicated four times in Completely Randomized Design (CRD). Different chemical, physical methods, food preservatives and packaging were used to control the black mould fruit rot. Result: The epidemiological studies revealed that injury to the pomegranate fruits was found to be a prerequisite for infection. All the fruits inoculated by cork-wounding, pin-pricking, scrapping and rubbing method exhibited symptoms of rot. Cork-wounding proved to be the most efficient method of inoculation. Post-harvest dipping in hot water, fungicides, oils and food preservatives provided effective control of the rot. Oil suspensions were found effective in preventing the rot. Food preservatives were also found effective in preventing rot, potassium metabisulphite (KMS) 0.5 percent followed by sodium benzoate 0.5 percent proved most effective against the rot in both pre-and post-inoculation treatments. Packaging for postharvest storage showed very good performance in maintaining the quality of pomegranate fruits up to 12 weeks.

Improving pomegranate fruit quality by short-term hypobaric treatment combined with modified atmosphere packaging storage

ISHS IV International Conference on Fresh-Cut Produce: Maintaining Quality and Safety Improving pomegranate fruit quality by short-term hypobaric treatment combined with modified atmosphere packaging storage

The Influence of Internal Packaging (Liners) on Moisture Dynamics and Physical and Physiological Quality of Pomegranate Fruit during Cold Storage.

Weight loss and decay are common physiological disorders during postharvest handling and storage of pomegranates. The study focused on relating the ability of plastic liners as internal packaging to modify both gaseous and moisture atmosphere around the fruit to moisture dynamics and physical and physiological quality of pomegranate fruit (cv. Wonderful) during storage. Fruit were packed with no-liner, non-perforated ‘Decco’, non-perforated ‘Zoe’, micro-perforated Xtend®, 2 mm macro-perforated high density polyethylene (HDPE), and 4 mm macro-perforated HDPE plastic liners. After 84 days of storage at 5 °C and 90–95% relative humidity (RH), fruit packed with no-liner lost 15.6 ± 0.3% of initial weight. Non-perforated (Decco and Zoe) liners minimised losses to 0.79 and 0.82% compared to Xtend® micro-perforated (4.17%) and 2 mm HDPE (2.44%) and 4 mm macro-perforated HDPE (4.17%) liners, respectively. Clearly, micro- and macro-perforation of liners minimised moisture condensation, fruit decay, and shrivel severity. Micro-perforated Xtend® and macro-perforated 4 mm HDPE were the best treatments in minimising postharvest losses that are often associated with inadequate environment control inside packaging compared to the use of non-perforated liners.

Influence of lemongrass (Cymbopogon flexuosus (Nees ex Steud.) essential oil yield under inter - cropping with pomegranate (Punica granatum L.)<em> </em>with special reference to the plant - soil relationship

The rain - fed/oasis areas, where lemongrass and pomegranate are grown as intercropping crops, are considered as the best ecosystem with particular properties. No research has been made to investigate the relationship between lemongrass essential oil and pomegranate fruit quality in such an environment. A comparison between pomegranate trees was intercropped with lemongrass crop and regular orchards with full sun conditions have been investigated in terms of yield of lemongrass essential oil and pomegranate fruit quality. The intercropped microclimate was more favourable for the production of lemongrass essential oil and pomegranate arils with attractive red colour and high total anthocyanin content. Pomegranates under these conditions contained total volatile content that was about two times higher than that in separate fruits. Particularly, hexanal and limonene were the most abundant compounds characterizing the aroma profile of fruits cultivated under intercropped, and their arils were the most appreciated in terms of colour, odour, and taste by Indian consumers. However, fruits from partial shade oasis provided the sweetest juices with high concentrations of glucose and fructose. Titratable acidity and total organic acid content were also higher in fruits grown under the two conditions. Red colour intensity, monoterpenes, hexanal, citric and quinic acids were useful to discriminate full shade oasis. These compounds seem to contribute to the typical organoleptic properties of oasis pomegranate fruits. The correlations between intercropped varieties of pomegranate and lemongrass, irrigated water, soil, and manure factors, elevated moisture in the soil in the intercropping impaired the expression of high yield of fresh herb and lemongrass oil of the good quality and pomegranate fruits production.

Methyl jasmonate effects on pomegranate fruit yield and quality at harvest and during storage depend on the applied concentration

Methyl jasmonate effects on pomegranate fruit yield and quality at harvest and during storage depend on the applied concentration

Effect of regulated deficit irrigation on pomegranate fruit quality at harvest and during cold storage

The effect of regulated deficit irrigation (RDI) strategies on fruit yield and quality at harvest and during cold storage at 5 °C of Wonderful pomegranates was studied. Three irrigation strategies were tested: control strategy (C) using farm irrigation with 100% of crop evaporation (ETc), and two RDI strategies where 25% of ETc was applied during flowering and fruit set (RDI 1) and during the final phase of fruit growth and ripening (RDI 2). The RDI 1 approach reduced the pomegranate yield. Conversely, the RDI 2 allowed a similar pomegranate yield to C treatment. Fruit morphological characteristics were not affected by RDI at harvest and during cold storage. Both RDI strategies resulted in fruits with higher aril percentages. Physicochemical parameters of fruits at harvest and during cold storage were not affected by irrigation strategies, except the total soluble solids content that was higher in fruits from RDI 2 than in those from C and RDI 1. During storage, a reduction of the fruit weight and size was observed, particularly in the first 15 days of storage. The total soluble solids content and titratable acidity decrease, while pH increases with storage. At harvest and during cold storage, the total phenolic content and antioxidant activity evaluated by ABTS+ assay did not differ among irrigation treatments, whereas using a FRAP assay fruits from RDI trended to have higher antioxidant activity than those from C treatment. Total phenolic content and ABTS+ values were lower at the final of storage time than on the first day. Present results showed that RDI strategies applied in a final phase of fruit growth and ripening could be a convenient irrigation strategy for commercial Wonderful orchards in the south of Portugal, allowing improve the fruit quality with a water saving of 14.6%.

Impact of chitosan in combination with potassium sorbate treatment on chilling injury and quality attributes of pomegranate fruit during cold storage.

The impact of chitosan (CH) and potassium sorbate (PS) on quality attributes of pomegranate fruits (cv. Malas e Saveh) was evaluated during 90days of storage at 4°C and 85%-90% relative humidity. The CH as well as the combined treatments (CH+PS) were effective in decreasing the chilling injury (CI) symptoms, electrolyte leakage, and malondialdehyde contents of fruit peel. Furthermore, CH, PS, and CH+PS treatments enhanced the activity of DPPH radical scavenging, and antioxidant enzymes of arils, and preserved the ascorbic acid content at high levels during the storage period. Fruits treated with CH1% + PS10% and CH2% + PS10% exhibited the lowest decay incidence and weight loss. Higher content of arils' phenols, flavonoids, and anthocyanin was observed in treated-fruits as a result of more activity of phenylalanine ammonia-lyase (PAL) and low activity of polyphenol oxidase (PPO). Consequently, CH+PS showed positive effects on the storage life of pomegranate fruits in terms of CI, decay incidence, and also nutritional values. PRACTICAL APPLICATIONS: Enhancement of chilling tolerance of pomegranate fruits during cold storage condition is a crucial issue. Application of CH coating alone or in combination with potassium sorbate could decrease the CI symptoms and preserved peel cell membrane integrity by maintaining electrolyte leakage (EL) and malondialdehyde in lower levels. Also, these treatments prevent weight loss and decay incidence in peel, and increase the activity of phenylpropanoid pathway and antioxidant systems in arils. All in all, usage of CH edible coating (2%) plus PS (10%) illustrated high efficiency in alleviating CI, decay incidence, and preserving nutritional quality of pomegranate fruits.

Effects of Postharvest Edible Coatings to Maintain Qualitative Properties and to Extend Shelf-life of Pomegranate (Punica granatum. L)

Regardless of the low respiration rate in pomegranate fruits, it is a greatly perishable product. An alternative to maintain quality and prolong the shelf life of pomegranate fruits could be edible coatings. In the present study, three different edible coatings including: 1% chitosan, 1000 mg L-1 thymol, and their combined were investigated on the postharvest quality of pomegranate fruits. Changes in weight loss, fruit firmness, total soluble solids (TSS), titratable acidity (TA), juice pH, anthocyanin, total phenolic, and flavonoids content, sensory characteristics and fungal decay incidence of fruits were evaluated during 30, 60, 90 and 120 days storage at 6 °C. The results showed that coated fruits with 1% chitosan + 1000 mg L-1 thymol significantly decreased weight loss and firmness than uncoated fruits. Furthermore, the coated fruits with 1% chitosan + 1000 mg L-1 thymol exhibited significantly higher anthocyanin, total phenolic, flavonoids content, and sensory characteristics than the control treatment. The minimum shelf-life (83.33 days) was observed in uncoated fruits, while the maximum shelf-life (108.33 days) was recorded in fruits coated with 1 % chitosan + 1000 mg L-1 thymol. Duration of storage had a significant effect on weight loss, firmness, juice pH, anthocyanin content, total phenolic content, flavonoids content, sensory characteristics, and decay, whereas there was no significant effect on TSS, TA, and TSS/TA. In conclusion, the combined application of chitosan and thymol can provide a useful alternative for shelf life extension of pomegranate fruits.

Preharvest Application of Oxalic Acid Improved Pomegranate Fruit Yield, Quality, and Bioactive Compounds at Harvest in a Concentration-Dependent Manner

The effects of oxalic acid (OA) applied in preharvest on pomegranate crop yield and quality properties have not yet been investigated. Pomegranate trees were treated with OA at 1, 5, and 10 mM along the developmental growth cycle during 2016, from full blossom until harvest, and the fruit diameter was recorded monthly. The yield was significantly higher in OA-treated pomegranate trees, the on-tree ripening process being promoted in a concentration-dependent manner. With respect to quality traits, OA at 10 mM showed better results in terms of firmness, external color due to a red color enhancement, and respiration rate and sensory attributes. Then, a second-year experiment was performed with OA at 10 mM, and crop yield and fruit quality results were confirmed. In addition, an increase in glucose and total acidity, specifically malic and ascorbic acids, was observed in OA 10 mM-treated pomegranate fruit. Bioactive compounds were also higher in OA-treated fruit than control, the 10 mM concentration being the most effective in increasing total phenolics, total anthocyanins, and total antioxidant activity. Overall, results suggest that OA applied at 10 mM as preharvest treatment could be an effective tool to enhance pomegranate crop and quality and to improve the content of health-related compounds.

Maintenance of quality and bioactive compounds in pomegranate fruit (Punica granatum L.) by combined application of organic acids and chitosan edible coating.

Pomegranate is a subtropical fruit that affects its cold storage. To ameliorate chilling injury, fruits were treated with malic acid (50 and 100mM MA) and oxalic acid (5 and 10mM OA), and then, coated with 2% chitosan (CH) and stored at low temperature (2°C) for 4months. Treatments significantly delayed the development of browning signs and reduced malondialdehyde and hydrogen peroxide of arils as compared to control. CH+ 5mM OA resulted in the highest catalase activity in arils during storage. Anthocyanin, ascorbic acid, total phenolic compound, and antioxidant activity of arils were higher in CH+ 5mM OA and CH+ 50mM MA-treated fruit. Also, the minimum PPO and POD activity of arils was found in CH+ 5mM OA. Overall, CH edible coating following organic acids treatment, and especially 5mM OA and 50mM MA are beneficial treatments for preserving the quality of pomegranate fruit during storage. PRACTICAL APPLICATIONS: Pomegranate fruit waste is high due to chilling sensitivity during cold storage. Coating fruit with 2% chitosan (CH) alone and with malic acid (50 and 100mM MA) and oxalic acid (5 and 10mM OA) could ameliorate chilling injury. Treatments reduce the development of browning signs. Overall, CH edible coating combined with 5mM OA and 50mM MA were the most effective treatments for ameliorating the chilling injury of pomegranate fruit.

Maintenance of quality and bioactive compounds of cold stored pomegranate (Punica granatum L.) fruit by organic acids treatment.

Pomegranate is a subtropical and chilling sensitive fruit. In this study, the effects of malic acid (50 and 100 mM) and oxalic acid (5 and 10 mM) on quality properties of pomegranate during cold storage (2 ℃) were investigated. The lowest weight loss was observed in fruit treated with 50 mM malic acid. Malic acid had positive effects on color parameters (L*, a*, and b*) of pomegranate at low temperature. Organic acid treatments reduced chilling injury, malondialdehyde, and hydrogen peroxide and increased catalase activity. The lowest activity of polyphenol oxidase and peroxidase was observed in 5 mM oxalic acid-treated fruit. On the other hand, fruit treated with 50 mM malic acid showed the maximum ascorbic acid and citric acid content. The most antioxidant activity was found in fruit treated with 5 mM oxalic acid and 50 mM malic acid. Also, all treatments except 10 mM oxalic acid and 100 mM malic acid resulted in higher titratable acidity than control fruit. Overall, 50 mM malic acid and 5 mM oxalic acid were the most effective for preserving the quality of pomegranate fruit at low temperature.