Tomato (Lycopersicon esculentum Mill.) fruit, cv. Solar Set, were harvested at the mature-green stage and treated with 50 μL·L-1 ethylene at 20 °C. Individual fruits at the breaker stage (<10% red color) were dropped onto a solid surface to induce internal bruising. Dropped and undropped fruit were stored at 20 °C until red-ripe, at which time pericarp, placental, and locule tissues were excised. Tissues from dropped tomatoes were examined for evidence of internal bruising and all tissues were analyzed for selected volatile profiles via headspace analysis. Individual volatile profiles of the three tissues in bruised fruit were significantly different from those of corresponding tissues in undropped, control fruit, notably: trans-2-hexenal from pericarp tissue; 1-penten-3-one, cis-3-hexenal, 6-methyl-5-hepten-2-one, cis-3-hexenol and 2-isobutylthiazole from locule tissue; and 1-penten-3-one and β-ionone from placental tissue. Alteration of volatile profiles was most pronounced in the locule tissue, which was more sensitive to internal bruising than the other tissues. Changes observed in the volatile profiles appear to be related to disruption of cellular structures.
Celso L. Moretti, Elizabeth A. Baldwin, Steven A. Sargent, and Donald J. Huber
Douglas D. Archbold, Ann M. Clements, T.R. Hamilton-Kemp, and R.W. Collins
Prior work indicated that volatile compounds produced by macerated strawberry fruit occurred at levels capable of affecting pathogen development. To determine if a less-severe injury, such as bruising, would alter the volatile profile of strawberry fruit, the headspace volatiles from ripe `Tribute' strawberry fruit were sampled with SPME fiber during the 15 min immediately following and from 75 to 90 min following application of a compression bruise. The compression bruise was applied with a force gauge, and fruit were kept in a closed bottle at room temperature during the study. Of the 14 major volatile products consistently produced by all fruit, acetate esters derived from hexanal, (E)-2-hexenal, and (Z)-3-hexenal increased most, over 50%, in response to bruising during the first interval. During the later interval, bruised fruit produced over 50% more (E)-2-hexenyl acetate and hexyl acetate than control fruit. Most notably, the ratio of levels of (E)-2-hexenyl acetate produced by bruised compared to control fruit were the highest among all 14 major volatiles, over 150% more after 15 min and 270% more at 90 min. Headspace levels of the 6-carbon acetate esters declined for both control and bruised fruit between 15 and 90 min, while levels of the other major volatiles increased. The other 11 volatile compounds were commonly identified aroma volatiles. Headspace levels of some of these were also higher from bruised than control fruit. In particular, headspace levels of ethyl butyrate were increased by bruising 13% after 15 min but over 100% after 90 min, the most of any volatile product other than (E)-2-hexenyl acetate.
Celso L. Moretti, Steven A. Sargent, Donald J. Huber, and Rolf Puschmann
Tomato (Lycopersicon esculentum L.) fruits, cv. Solarset, were harvested at the mature-green stage and treated with 50 μL/L ethylene at 20C. Breaker fruits (<10% red coloration) were dropped from 40 cm onto a smooth, solid surface and held along with undropped fruits at 20°C and 85% relative humidity. At table-ripe stage, pericarp, placental, and locular tissue were individually excised and analyzed for total carotenoids, total soluble sugars, soluble solids content, titratable acidity, density (locule tissue), polygalacturonase activity, and electrolyte efflux (pericarp tissue). Internal bruising caused by impact forces significantly affected pericarp and locule tissues, but not placental tissue. For bruised locule tissue, total carotenoids content decreased by 37.1%, vitamin C content by 15.6%, and titratable acidity by 15.3% as compared to control. However, density was increased by 3.0%. For bruised pericarp tissue, vitamin C content decreased by 16.5%, while polygalacturonase activity and electrolyte efflux increased by 33.3% and 24.8%, respectively. The development of abnormal ripening following an impact was confined to locule and pericarp tissues and appears to be related to the disruption of cellular structure and stimulation of enzymic activity.
Daniel Valero, Domingo Martínez, Fernando Riquelme, and María Serrano
The polyamines putrescine, spermidine, and spermine (free form) were measured during 48 hours at 20 °C after mechanical damage of `Fortune' and `Clementine' mandarins (Citrus reticulata Blanco.) with forces of 0, 10, 20, and 30 N. In control fruits (without damage), the three polyamine levels were higher in `Fortune' than in `Clementine', and putrescine and spermine levels tended to diminish during the experiment, while spermidine levels increased slightly in `Fortune' and showed a prominent peak in `Clementine' 6 hours after storage. In general, polyamine levels increased in the peel following bruising. The magnitude of this effect differed for both cultivars and applied forces. Putrescine levels were positively correlated with the applied force in `Fortune', while in `Clementine' only the 20 N force was effective. Spermidine levels also increased in `Fortune' following injury, but there was no difference in effects among the three forces used. Only the 10 N force increased spermidine levels significantly in `Clementine'. Spermine levels were slightly higher than control levels after 48 hours, but not higher than initial levels.
Carlos H. Crisosto, David Garner, Jim Doyle, and Kevin R. Day
Respiration rate and bruising incidence were assessed in new cherry (Prunus avium L.) cultivars adapted to high temperatures. `Bing', `Brooks', `Tulare', and `King' respiration rates were evaluated at 0,5,10, and 20C, and bruising susceptibilities at 0, 10, 20, and 30C. `Bing' was the least susceptible to bruising and had the lowest respiration rate at all temperatures. Respiration rate increased with temperature in all cultivars. Impact bruising damage was greatest in all cultivars when fruit flesh was below 10C. Vibration damage was not influenced by fruit temperature. Our results suggest that the cherry cultivars assessed should be handled at temperatures between 10 and 20C during packing to minimize bruising damage. Due to increased respiration rates at higher temperatures, however, fruit should be cooled to 0C within 4 to 6 hours after harvest.
M.D. Ferreira, S.A. Sargent, J.K. Brecht, and C.K. Chandler
Individual strawberry (Fragaria ×ananassa Duch.) fruits at cooled or ambient pulp temperatures were subjected to compression or impact forces to determine sensitivity to bruising. Fruits were more resistant to compression bruising at lower temperatures, but were more resistant to impact bruising at ambient temperatures. `Chandler' fruits at 1C or 30C were compressed (9.8 N for 2 s); after 24 h @ 24C, bruise volumes were 0.27 cm3 and 0.65 cm3, respectively. Following a single impact from 13 cm, fruits at 1C or 24C had bruise volumes of 0.21 cm3, and 0.10 cm3, respectively. Increasing impact height to 38 cm caused bruise volumes of 0.31 cm3 and 0.16 cm3 for fruits at 1C and 24C, respectively. The potential exists to improve packout quality and efficiency for value-added strawberry packs. Due to greater resistance to impacts at ambient temperatures, strawberries could be bulk-transported to a central facility, and graded and packed on an appropriately designed packing line. Care must be taken to avoid compression bruising at harvest.
Celso L. Moretti, Steven A. Sargent, Donald J. Huber, Adonai G. Calbo, and Rolf Puschmann
`Solar Set' tomatoes (Lycopersicon esculentum Mill.) were harvested at the mature-green stage of development and treated with 50 μL·L-1 ethylene at 20 °C. Breaker-stage fruit were dropped from 40 cm onto a solid surface to induce internal bruising and held along with undropped fruit at 20 °C. At the ripe stage, pericarp, locule, and placental tissues were analyzed for soluble sugars, vitamin C, pigments, titratable acidity, soluble solids content, pericarp electrolyte leakage, extractable polygalacturonase activity, and locule tissue consistency. Bruising significantly affected chemical composition and physical properties of pericarp and locule tissues, but not placental tissue. For bruised locule tissue, carotenoids, vitamin C, and titratable acidity were 37%, 15%, and 15%, lower, respectively, than unbruised fruit. For bruised pericarp tissue, vitamin C content was 16% lower than for unbruised tissue, whereas bruising increased electrolyte leakage and extractable polygalacturonase activity by 25% and 33%, respectively. Evidence of abnormal ripening following impact bruising was confined to locule and pericarp tissues and may be related to the disruption of cell structure and altered enzyme activity.
Robert K. Prange, Peter A. Harrison, and Jennifer R. DeEll
In a 2-year study, `McIntosh' apples were stored in a CA regime of 4.5% CO2 + 2.5% O2. Within the CA cabinets there were three humidity levels: >75% RH (CaCl2 salt in the chamber), >90% RH (ambient), or >95% RH (distilled water in the chamber). After removal at 4 and 8 months, the fruit were warmed to handling temperatures of 0C, 10C, or 20C and subjected to three levels of impact bruising of 0, 10, or 20 lb with a Ballauf pressure tester with a 1.5 × 1.5-cm tip. The results showed that low-humidity CA storage decreased visible bruising. Although visible shrivel was not observed, the low-humidity treatment may increase the possibility of its occurrence. Respiration, measured as O2 consumption or CO2 production immediately after removal from CA storage, was lowest in low humidity (>75% RH) and highest in ambient humidity (>90% RH) CA storage. The humidity treatments did not affect firmness, soluble solids, titratable acids, or ethylene production. Increasing the temperature during post-storage handling decreased the amount of visible bruising without affecting other variates such as firmness, soluble solids, titratable acids, respiration, or ethylene production.
Nancy L. Schulte, Edward J. Timm, and Galen K. Brown
`Redhaven' peaches [Prunus persica (L.) Batsch] were dropped onto several impact surfaces to determine impact conditions that initiate bruising. After impact, the peaches were tested for flesh firmness and sorted into firm, soft, and very soft groups for bruise analysis. The drop height that did not bruise decreased as fruit softened. The peach shoulder area bruised most easily. A drop of only 8 mm onto a hard surface initiated bruising on a soft peach, whereas a Poron 15250 cushion could protect the peach for a ≤85-mm drop. Impact damage threshold estimates were developed for the three flesh firmness conditions. The threshold estimates and impact history information collected by an instrumented sphere can be used to develop handling equipment design and operation guidelines that essentially avoid impact bruises on peaches.
James F. Thompson, Joseph A. Grant, Eugene M. Kupferman, and Jerry Knutson
Damage (pitting and bruising) to sweet cherries during packing line operations was evaluated in a 3-year study conducted in California, Washington, and Oregon. A large percentage of cherries sampled before packing developed damage symptoms (28% in 1992 and 35% in 1993 and 1994), suggesting that damage is imparted during growing, harvest, or transport to the packing house. Packing line operations caused an average of 39% pitting and 10% bruising. The greatest damage was imparted by cluster cutters (20% pitting) and shower type hydrocoolers (19% pitting). Results from this study demonstrate that packing line damage can be reduced by slowing fruit speed in cluster cutters, operating cluster cutters at high fruit-throughput rates, and reducing water drop height in shower hydrocoolers.