STORAGE OF IMMATURE GREEN MANGO (Mangifera indica, L.) FRUIT FOR PROCESSING

A suitable method of storing, for processing immature green mangoes in a fresh state was sought. Fruits were stored at three temperatures (1OC, 20C and 30C) either in sealed low density polyethylene (LDPE) bags or paper bags or they were waxed before storage. Storage above 20C proved unsuitable for fruits held longer than one week. Sixty percent of fruits stored at 10C in LDPE bags showed no evidence of pathological infection. Development of severe chilling injury limited the use of waxed and control fruits beyond 14 days at 10C. There were no visible symptoms of chilling injury in fruits stored at 10C in LDPE bags. The majority of fruits stored in LDPE bags at 10C maintained good quality characteristics with acceptable flavor and minimal changes in chemical composition up to 21 days.     

Jam Processing Effect on Phenolics and Antioxidant Capacity in Anthocyanin-rich Fruits: Cherry, Plum, and Raspberry

ABSTRACT: Four cultivars of sour cherries (Balaton, Karneol, Kroeker and Northstar), 2 cultivars of plums (BY 8158.50 and Methley), and 1 red raspberry cv. Prelude were analyzed for total phenolics, antioxidant capacity, and total anthocyanins before and after jam production to evaluate their changes after thermal processing. Fruits had total phenolics ranging from 245.7 to 398.5 mg gallic acid equivalent (GAE)/100 g. Antioxidant capacity of fruits ranged from 354.8 to 692.3 mg/100 g, expressed as vitamin C equivalent antioxidant capacity (VCEAC). Total anthocyanins of fruits ranged from 30.9 to 67.1 mg cyanidin 3-glucoside equivalent (CGE)/100 g. In 100 g of jam, total phenolics varied from 132.9 to 218.9 mg GAE, while antioxidant capacity ranged from 205.6 to 373.5 mg/100 g VCEAC. Jams had total anthocyanins of 5.4 to 30.4 mg CGE/100 g. On the basis of fresh fruit (100 g), the processing and heating during jam making generally decreased the contents of total phenolics, VCEAC, and total anthocyanins. Major losses occurred in anthocyanin content where overall retention varied from 89% to 21%. HPLC analysis of individual anthocyanins from cherry cv. Balaton to its jam showed that processing caused 90% decrease in anthocyanins. The results indicated that more than 73% total phenolics and more than 65% antioxidant capacity were retained after processing fruits into jams. Optimization of food processing would help to conserve the bioactive phenolic compounds in fruits.     

EFFECTS OF PHOMOPSIS PEACH ROT ON PULP LOSSES AND PUREE QUALITY

The effects of a Phomopsis sp. on four peach (Primus persica) cultivars and three fruit maturities were evaluated for pulp losses and quality changes of peach puree. Fruits were inoculated with 2 mm × 2 mm of agar with Phomopsis mycelium and incubated at room temperature (24 to 26 C) for 3 days. The early-maturing cultivar Goldilocks had higher susceptibility to Phomopsis than the late maturing Babygold 8. Mature fruit had a slightly higher degree of susceptibility to Phomopsis than less mature fruit, except for Goldilocks, which showed equal susceptibility at all maturity stages. Pulp losses, percentage of decayed tissue, titratable acidity, Howard mold counts, soluble solids (SS), SS/acid ratio, viscosity, pH and changes in color were variable among cultivars and maturities. Puree made with 1% or more Phomopsis-decayed tissue may be unacceptable because of a high (16–75%) mold count.     

EXTENSION OF BITTER GOURD (MOMORDICA CHARANTIA L.) STORAGE LIFE THROUGH THE USE OF REDUCED TEMPERATURE AND POLYETHYLENE WRAPS

Bitter gourd (Momordica charantia L.) fruits were stored individually wrapped in low density polyethylene (LDPE) film or unwrapped for up to 21 days at 5–7C, 20–22C and 28–30C, respectively. Assessment was done on several quality parameters including marketable quality. Storage offilm-wrapped fruit at 5–7C resulted in extension of shelf-life in excess of two weeks and delayed appearance of chilling injury symptoms. Additionally, film-wrapped fruits stored at 5–7C were still marketable after 21 days, had lowest fresh weight losses, less softening, reduced incidence of postharvest rots and minimal changes in vitamin C content and pH. Storage of individually wrapped fruits at reduced temperatures therefore offers an effective method of prolonging the shelf-life of bitter gourd.     

Influence of moderate heat pre-treatments on physical and chemical characteristics of kiwifruit slices

The effect of mild heat treatments, applied to whole kiwifruit, on physical characteristics and chemical composition of minimally processed fruit was studied. Fruits were subjected to heat treatments at 45 °C for 25 and 75 min, cooled for 24 h, minimally processed and stored at 4 °C for 12 days. Heat-treated fruits showed increased respiration rates in the first 2 days of storage. Samples colour was marginally affected either by heat treatments or by minimal processing. The application of heat treatments leads to an increment of slices firmness due to cross linking between demethylated galacturonic acid chains and endogenous calcium. An increment in sucrose, L-malic, citric, quinic and ascorbic acids was observed as a consequence of applied heat treatments. Heat treatment at 45 °C for 25 min applied to whole fruits allows quality retention of minimally processed fruit during 9 days at 4 °C.     

ETHYLENE CAPSULE PROMOTES EARLY RIPENING OF 'd'ANJOU' PEARS PACKED IN MODIFIED ATMOSPHERE BAGS

‘d'Anjou’ pears (Pyrus communis, L.) harvested commercially with flesh firmness of 64.5 N were incapable of ripening normally at 20C within 60 days of air storage at ‐1C (denoted as “under‐chilled” fruits). When under‐chilled ‘d'Anjou’ fruits (8 fruits, total fruit weight of 1.8 kg) were packed in a 3.8‐liter perforated bag inserted with an ethylene capsule, fruit would ripen normally at 20C. The ethylene concentration in the packed bag maintained no less than 100 ppm after 4 days at 20C, and declined to about 25 ppm on day 7. Regardless of the storage length, ripened fruit induced by the ethylene capsule developed high buttery and juicy texture. If ‘d’ Anjou’ fruit had been stored at ‐1C for less than 30 days, ripened fruit lacked high flavor quality. Flavor quality of ripened fruit improved rapidly when the fruit had been stored for longer than 30 days.     

SHELF-LIFE AND QUALITY OF‘NAVAHO’ AND ‘SHAWNEE’ BLACKBERRY FRUIT STORED UNDER RETAIL STORAGE CONDITIONS1

The quality of soft-fruited (‘Shawnee’) and firm-fruited (‘Navaho’) blackberry cultivars held under simulated retail conditions was determined. Leakage and decay increased during storage and exceeded 20% in 'Shawnee’ fruit after 14 days at 2C or 7 days at 5C, while ‘Navaho’ held under similar conditions was still marketable (<10% decay). Transferring fruit to 20C for 2 days after low temperature storage intervals was detrimental to fruit quality, resulting in increased weight loss, leakage, decay and softening in both cultivars. After retail warming, ‘Shawnee’ fruit lost 25% of marketable fruit while‘Navaho’ had a 10% loss. Soluble solids concentration did not change significantly during storage, but titratable acidity declined 40–50%. Anthocyanin content increased from 20–100% depending on cultivar, storage temperature and storage intervals. The sugar composition of blackberries before storage was about 10, 260 and 260 mg/g dry weight, glucose, and fructose, respectively. Sucrose and glucose decreased and fructose increased slightly during storage. Warming fruit after low temperature storage did not accelerate loss of total sugars. If held constantly at 2C, ‘Navaho’ could be held 21 days.     

Strawberry quality as a function of the ‘high pressure fast cooling’ design

Oso Grande strawberries were picked, wrapped with polyvinyl chloride film, and finally cooled by ‘high pressure fast cooling’ units with slight differences in design in terms of number of fans functioning and ventilation spacer widths. The effect on strawberry quality of these cooling cells was evaluated compared to room-cooled fruits, and when compared to quality parameter values at fruit gathering. Quality evaluations by means of determination of main sugars and organic acids, colour, firmness, total soluble solids, titrable acidity and pH assessments were carried out at different commercial stages, immediately after cooling, after 3 days at 2 °C simulating refrigerated transport, and after 4 days at 17 °C storage (shelf-life). Reducing (by half) the ventilation spacer (V cell), resulted in a 20% higher air speed and a 20% faster cooling than control units (N cell), while units using half of the fans (F cell) showed a lower air speed (45%) and a 30% more time to cool down the product. These modifications also affected strawberry quality. Fruits from the fastest cooler cell, V cell, showed a different quality pattern compared to fruits from N and F cells, with a higher sucrose inversion and less glucose and fructose contents. V cell-cooled strawberries presented a lower content of citric, malic and ascorbic acids during shelf-life. However, fruits cooled by the V cell showed the highest marketable fruit percentage, although with a decrease in red colour compared to fruit at gathering, and fruit cooled by the N or F cells. In these cells, fruit colour remained practically unchanged along the different commercial stages including the long shelf-life period.     

Industrial processing effects on chestnut fruits (Castanea sativa Mill.) 3. Minerals,free sugars,carotenoids and antioxidant vitamins

The major aim of this study was to evaluate the effects of industrial processing on the composition of minerals, free sugars, vitamins and pigments in fruits of chestnut cultivars at four stages of industrial processing (A–fresh; B–after 3 months storage at ± 0 °C and relative humidity = 90%; C–after flame peeling at 800 °–1000 °C for 1–2 s; D–after freezing in a tunnel with a CO₂ flow at ?65 °C for 15–20 min) from two harvest years. Potassium and phosphorous were predominant in the fruits of all cultivars for both harvest years. Calcium, magnesium, iron, zinc and manganese were also present in the fruits. Fruits from both harvest years had a significant content of free sugars, with sucrose predominating, and these sugars were more affected by the processing stage. Significant levels of lutein, lutein esters, γ‐tocopherol and vitamin C were also found in the chestnut fruits. Fruit carotenoids and vitamin C significantly decreased during the industrial processing.     

Influence of Sulfur Dioxide Generators on Red Raspberry Quality During Postharvest Storage

Hand harvested ‘Meeker’ red raspberries were held at 4°, 14°, and 25°C for up to 12 days using two types of sulfur dioxide generating pads. Visual mold ratings were lower for fruits held with either SO₂ generator, but Howard Mold Count did not differ between the generators and the control fruits. Fruits stored with the generators were brighter and redder in color than controls when stored at 4°C. Irregular bleaching of anthocyanins from drupelets occurred when fruits were stored at 14°C or higher. Use of SO₂ generators is not recommended for fresh market fruit or nonheat treated processing fruit due to the bleaching and due to SO₂ residues in the fruit.     

Quality of Gamma Irradiated California Valencia Oranges

California Valencia oranges were irradiated at 0.30, 0.50, 0.75 and 1.0 kGy for quality evaluation and potential use of gamma-radiation as an alternative quarantine treatment and for fresh market life extension. Fruits were ocean-freighted to Honolulu, irradiated at the Hawaii Research irradiator 8 days after harvest, then stored for 7 wk at 7°C or 4 wk at 7°C and 2 wk at 21°C (6 wk total). Treatments of 0.75 kGy maintained fruit qualities at low storage temperature (7°C) up to 7 wk while 0.50 kGy retained qualities when fruits were stored at 21°C. Gamma irradiation of Valencia oranges at 0.26–0.30 kGy can achieve fruit fly disinfestation at probit 9 security level while preserving market qualities including organoleptic qualities, ascorbic acid, total acids, and total soluble solids.     

EXTENDED STORAGE LIFE OF LITCHI FRUIT USING CONTROLLED ATMOSPHERE AND LOW TEMPERATURE

The postharvest quality of litchi (Litchi chinensis Sonn.) cv. Bombay stored under controlled atmosphere (CA) at 3.5% O₂and 3.5% CO₂, 2C temperature and 92–95% relative humidity was studied. Fruits were also held in regular atmosphere (RA) maintained at 2C temperature and 92–95% relative humidity. Fruits kept at normal ambient conditions were used as controls. Various quality attributes measured revealed that fruits stored in CA exhibited Hunter “a” values of 11.2 after 56 days of storage, indicating the beneficial effect of CA on retaining the red color of litchi fruits. Fruits held in RA exhibited Hunter “a” values (7.9) lower than that of CA‐stored litchi, showing that browning of litchi was noticeable in RA. Loss of weight was lowest (4.9%) for the fruits stored in CA compared to those stored in RA (11.0%) and control (33.1%). Loss of acidity and ascorbic acid content of fruits stored in CA were less than that of RA. The smallest increase of litchi firmness and pericarp puncture strength of 2.2 and 3.9 times of initial level, respectively, were observed even after 56 days of storage in CA. Total soluble solid of litchi increased from 19.3° Brix at harvest to 23.0° Brix until 48 days of storage in CA after which it declined to 22.8 °Brix. The sensory evaluation of aril color and taste showed that the fruits held in CA were rated good throughout 56 days of storage.     

Effects of temperature on the ripening of mango fruit (mangifera indica L. var. tommy atkins)

The effects of temperature on the ripening of Tommy Atkins mango were studied. Ripening temperature can affect fruit colour, flavour and texture development differently. Fruits at 12°C did not ripen to full eating quality during the 16 days of the experiment. Sugar levels were comparable with those at other temperatures, but acid levels were higher; they retained some green coloration, had lower pulp carotenoids and showed incomplete softening. After 15 days at 17°C, fruits had softened and degreened to an acceptable level but had a poor pulp colour. They were comparatively high in sugars but were also high in acids, resulting in a low sugar:acid ratio. Fruits kept at 22, 27 and 32°C all showed the development of good quality characteristics of high chlorophyll breakdown, high pulp carotenoids, a good texture and a balanced sugar: acid ratio. Similar characteristics were shown at 37°C, although the peel generally appeared mottled and the pulp had slightly lower sugar:acid ratios.     

Physicochemical changes of sweet cherry fruits related to application of gibberellic acid

The influence of gibberellic acid on the physical and chemical properties of sweet cherry fruits during ripening (development of fruit colour) and at fruit maturity (firmness of fruits, cracking index, water uptake, soluble solids content, total acidity, fruit dimensions) of three sweet cherry cvs. ‘Van', ‘Sunburst' and ‘Elisa' grown in a climate with frequent rainfall during fruit maturation were studied. Fruits of cv. ‘Elisa' were prematurely picked because of cracking. A significant main effect of GA₃ treatment and significant main effect of cultivars were established in fruit colour development. The means of firmness and soluble solids content were systematically higher for the cherries of ‘Van' and ‘Sunburst' treated with GA₃ but they were not significant at =0.05. The fruit cracking was significantly smaller for GA₃-treated fruits of the cv. 'Sunburst' after 4 h in water. Gibberellic-treated fruits of both cultivars were larger in fruit weight than untreated fruits; the differences were significant at =0.10. Fruit dimensions: height, width and thickness of both cultivars were significantly affected by GA₃ treatment. The response of sweet cherry fruits to GA₃ spraying depended on the properties of the cultivar.     

Effect of exogenous fludioxonil postharvest treatment on physiological response,physico-chemical,textural, phytochemical and sensory characteristics of pomegranate fruit

The study investigated the effects of fludioxonil (FLU) on the postharvest quality of pomegranate fruit (cv. Wonderful). Fruits were dipped in FLU concentrations (control, 150, 300 and 600 mg/L) and stored for 4 months at 5?°C and 90–95% relative humidity (RH) plus an additional 4 days at 20?°C and 65% RH. Effects of FLU were evaluated on physiological responses, quality and sensory attributes. Results showed that fruit weight loss and decay incidence were reduced by FLU treatment, with fruit treated with 600 mg/L concentration showing the best results. Fruit respiration rate was more influenced by storage duration than FLU concentration. The severity and occurrence of physiological disorders increased with storage duration but were more pronounced in fruits treated with FLU. Storage duration influenced fruit colour whereas aril colour was affected by FLU concentration. Untreated fruit showed better aril redness and chroma although treated fruit also had acceptable red colour. Chemical quality attributes of fruit juice were not significantly affected by FLU concentrations. Fruit treated with FLU had significantly (p?<?0.05) higher total phenolic content during storage although lower ascorbic acid content was observed compared to untreated fruit. Treating fruit with FLU resulted in better sensory attributes with regards to crispness, juiciness and sweetness. Overall, this study showed that fruit treated with FLU at 600 mg/L had the best quality with respect to decay incidence, weight loss, total phenolics and sensory attributes.     

Maturity‐dependent chilling tolerance regulated by the antioxidative capacity in postharvest cucumber (Cucumis sativus L.) fruits

BACKGROUND: The aim of the present study was to reveal the effect of fruit maturity on the chilling tolerance of cucumber (Cucumis sativus L.) fruit and the oxidative and antioxidative mechanisms involved. Chinese mini‐cucumber (cv. Hangcui‐1) fruits were harvested at four developmental stages: Immature (3–8 days after anthesis (DAA)), Mature (9–16 DAA), Breaker (17–22 DAA) and Yellow (35–40 DAA). All fruits were stored at 2 °C for 9 days and rewarmed at 20 °C for 2 days. RESULTS: The chilling injury index declined with advancing fruit maturity. High superoxide anion radical production rate and hydrogen peroxide content were observed in Immature fruits after cold storage and rewarming. Under chilling stress, superoxide dismutase showed an early response. Fruits at earlier maturity stages exhibited higher catalase, ascorbate peroxidase and monodehydroascorbate reductase activities and glutathione content as well as its redox state, and lower peroxidase, dehydroascorbate reductase and glutathione reductase activities and ascorbate content as well as its redox state. CONCLUSION: Fruits at the earlier developmental stage are more susceptible to chilling injury, which is related to increased oxidative stress. High peroxidase activity and ascorbate content and maintenance of the latter's redox state appear critical to the chilling tolerance of cucumber fruits at later developmental stages. © 2012 Society of Chemical Industry     

Reduction of chilling injury in ripe Alphonso mango fruit in cold storage by temperature conditioning

The influence of ripening temperature and cold conditioning of pre-climacteric fruits on the incidence of chilling injury (CI) in ripe mango fruits cv. Alphonso during refrigerated storage was investigated. Fruits previously held and ripened at tropical ambient temperature (AT, 27–34°C) developed CI (skin staining or browning) when ripe fruits were subsequently stored at 5, 10, or 15°C for shelf-life extension. Fruits held and ripened at 20°C1°C, RH 85–90% showed little evidence of CI when subsequently stored at 5 or 10°C up to 14 days. Chilling injury in ripe mangoes was also avoided by holding pre-climacteric fruits for a minimum period of 30 days at 10°C and then ripening them at 27–34°C. The quality of the ripe mangoes remained good during cold storage for 7 days and were acceptable until 10–14 days with minimal changes in texture, flesh colour, carotenoids, total soluble solids, titratable acids and ascorbic acid. Shelf-life of ripe mangoes can thus be extended under refrigeration by pre-storage conditioning.     

Effect of heat treatment and individual shrink packaging on quality and nutritional value of bell pepper stored at suboptimal temperature

The goal of this study was to develop a technology for prolonged storage of pepper fruit at low temperature, based on physical treatments and packaging materials. Physical and compositional changes of red bell pepper fruit (Capsicum annuum L. cv.’Selika’) were monitored during 21 days of cold storage (at 2 °C) plus 3 days at 20 °C (market simulation). Fruits were treated with tap and hot water and stored without packaging or sealing each fruit in individual shrink packaging (Cryovac®). This research revealed that individual shrink packaging following prestorage with hot water rinse (55 °C for 15 s) over brushes, significantly reduced weight loss, softening, decay incidence and chilling injury, while maintaining a quality. The wrapped fruit ripened normally (carotenoid content increased) during shelf‐life period, when shifted to 20 °C after unwrapping. This study showed that antioxidant levels of pepper fruit may be preserved during storage.     

Effect of deficit irrigation on apricot fruit quality at harvest and during storage

The effect of different irrigation strategies on the fruit quality at harvest and during storage at 1 °C of 'Búlida' apricots (Prunus armeniaca L.) was studied. Irrigation treatments consisted of a control irrigated at 100% of crop evapotranspiration (ETc) throughout the season, and two deficit irrigation treatments consisting of continuous irrigation at 50% of control, and regulated deficit irrigation (RDI) at 100% of ETc during the critical periods (second rapid fruit growth and early post‐harvest) and at 25% during the rest of the season. Fruits at harvest from both deficit irrigation treatments showed higher values of total soluble solids (TSS), titratable acidity and hue angle (h°) than control fruits, whereas their diameter, fresh weight, firmness and maturity index values were similar to those in the control. During the first 10 days of the 30‐day chilling storage period, higher TSS and h° values were found in deficit irrigated fruits, whilst the other parameters were similar for all treatments. Weight loss and fungal attacks (mainly Rhizopus sp. and Monilinia sp.) during a subsequent retail sale period of 4 days at 13 °C were the lowest in RDI. Deficit irrigation was demonstrated to be commercially advantageous for keeping fruit quality, saving considerable amounts of water. Copyright © 2007 Society of Chemical Industry