scholarly journals Heat-induced Volatiles in Fresh Broccoli

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 824A-824
Author(s):  
Charles F. Forney ◽  
Michael A. Jordan
Keyword(s):  
Dimethyl Sulfide ◽  
Dimethyl Disulfide ◽  
Heat Treatments ◽  
Hot Water ◽  
Physiological Changes ◽  
Induced Volatiles ◽  
Heat Treated ◽  
Relationship Of ◽  
Water Treatments ◽  
Methyl Thiocyanate

Heat can induce physiological changes in plant tissues, including the inhibition of broccoli senescence. Hot water treatments at 52C for 3 or more minutes may induce off-odors in fresh broccoli. The objective of this study was to identify heat-induced volatiles that may indicate physiological injury and/or be responsible for off-odors. Heads of fresh broccoli (Brassica oleracea L. Italica group cv. `Paragon') were immersed in water at 25C for 10 min (control); 45C for 10, 15, or 20 min; or 52C for 1, 2, or 3 min. Following treatment broccoli was held at 20C in the dark. Volatiles in the headspace above treated broccoli were trapped on Tenax-GR 2, 24, and 72 h after treatment and analyzed on a GC-MS. Heat treatments increased the production of ethanol, dimethyl disulfide (DMDS), dimethyl sulfide (DMS), dimethyl trisulfide (DMTS), hexenol, methyl thiocyanate, and several other unidentified compounds. Two hours after treatment, ethanol and hexenol concentrations in the headspace of all heat-treated broccoli were greater than those of the 25C/10 min controls. In the 52C/3 min-treated broccoli, headspace concentrations of ethanol, hexenol, DMDS, and methyl thiocyanate were 600-, 42-, 4-, and 4-fold greater than those of controls. After 72 h at 20C, concentrations of DMDS, DMS, and DMTS in broccoli from all six heat treatments were 10- to 200- fold, 8- to 35-fold, and 1.5- to 23- fold greater than those of controls, respectively. Concentrations of ethanol and methyl thiocyanate did not change relative to the controls during the additional 70 h at 20C. Concentrations of hexenol decreased in heat-treated broccoli during this time. The relationship of these volatiles to physiological changes and off-odor development in treated broccoli will be discussed.

scholarly journals 934 PB 524 HEAT TREATMENTS EXTEND THE SHELF-LIFE OF FRESH BROCCOLI

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 568b-568
Author(s):  
Charles F. Forney
Keyword(s):  
Shelf Life ◽  
Brassica Oleracea ◽  
Water Loss ◽  
Free Water ◽  
Heat Treatments ◽  
Hot Water ◽  
Delayed Senescence ◽  
Heat Treated ◽  
Water Treatments

Freshly harvested heads of `Cruiser' or `Paragon' broccoli (Brassica oleracea L. Italica group) were heat treated by holding in water for 1 to 40 min at 42, 45, 48, 50, or 52C. Control heads were held in air at 20C or in 25C water for 40 min. Controls turned yellow in about 3 days at 20C. Treatments at 42C delayed yellowing by 1 or 2 days, while treatments of 45, 48, 50, and 52C prevented yellowing up to 7 days at 20C. Hot water treatments had no effect on water loss of broccoli during storage. Incidence of decay was greater in treated broccoli stored wet compared to the dry control. However, when free water was removed by spinning following treatment, no difference in decay was observed. Treatment of broccoli at 52C for 3 or more min sometimes induced a distinct off-odor. When broccoli was held at 0C for 3 weeks following treatment no differences were observed between control and treated broccoli. However, when broccoli was warmed to 20C following storage at 0C, yellowing of treated broccoli was inhibited. Hot water treatments also delayed senescence at 20C when broccoli was treated following 3 weeks of storage at 0C.

scholarly journals Heat treatment effects on ACC oxidase activity of 'Keitt' mangoes

2003 ◽  
Vol 15 (3) ◽  
pp. 145-148 ◽  
Author(s):  
Renar João Bender ◽  
Eduardo Seibert ◽  
Jeffrey K. Brecht
Keyword(s):  
Ethylene Production ◽  
Oxidase Activity ◽  
Acc Oxidase ◽  
Hot Water ◽  
In Vitro Activity ◽  
Ethylene Dibromide ◽  
Heat Treated ◽  
Physical Treatments ◽  
Water Treatments

With the use of ethylene dibromide for mango disinfestation being ruled out, vapor heat or hot water treatments are the only alternatives for quarantine treatments of mangoes. Physical treatments such as heat treatments have been implicated in higher incidence of physiological disorders and enhancement of ripening processes. Therefore, the objective of the present work was to determine the effects of hot water treatments on ethylene production and on the in vitro activity of ACC oxidase. Cv. Keitt mangoes were immersed for 3 min in hot water at 53 °C or 90 min in water at 46 °C. Immediately after the treatments, some of the mangoes were analyzed for ACC oxidase activity and others were stored to be analyzed after 4 days at 12 °C. There was a significant increase in the ACC oxidase activity just after the hot water treatments. After 4 days, only the mangoes treated for 90 min maintained high ethylene production and ACC oxidase activity. Tissue from the outer layers of the mesocarp had higher enzyme activity compared to tissues from the innermost layers of the mesocarp of heat-treated mangoes.

scholarly journals Dry Heat and Hot Water Treatments for Disinfesting Cottonseed of Fusarium oxysporum f. sp. vasinfectum

Plant Disease ◽  
2010 ◽  
Vol 94 (12) ◽  
pp. 1469-1475 ◽  
Author(s):  
Rebecca S. Bennett ◽  
Patrick D. Colyer
Keyword(s):  
High Temperature ◽  
Fusarium Oxysporum ◽  
Heat Treatments ◽  
Seed Vigor ◽  
Hot Water ◽  
Seed Infection ◽  
Fusarium Spp ◽  
Dry Heat ◽  
Incubation Temperatures ◽  
Water Treatments

The potential of low- and high-temperature dry heat, and hot water treatments, for disinfesting cottonseed of Fusarium oxysporum f. sp. vasinfectum was investigated. Naturally infected seeds from Louisiana were air-heated at 30, 35, and 40°C for up to 24 weeks. Seed harvested from bolls inoculated with race 4 of F. oxysporum f. sp. vasinfectum were incubated in dry heat at 60, 70, and 80°C for 2 to 14 days, or were immersed in 90°C water from 45 s to 3 min. The effects on seed germination and vigor of hot water treatment and a subset of the high-temperature dry heat treatments were also examined in seeds of a Pima (Gossypium barbadense) and an Upland (G. hirsutum) cultivar. Low- or high-temperature dry heat did not eliminate Fusarium spp. from the seed, although seed infection declined more rapidly with higher incubation temperatures. High-temperature dry heat treatments effective in eliminating fusaria also significantly reduced seed vigor in both the Pima and Upland cultivars. Seed from all times of immersion in hot water were less frequently infected with Fusarium spp. than nontreated seed. Incidence of seed infection did not differ significantly among immersion times ranging from 75 s to 3 min. Immersion in 90°C water did not reduce germination or vigor at exposure times ≤120 s and ≤150 s for seeds of Pima and Upland cotton, respectively. Results from the hot water treatments suggest that thermotherapy may be optimized to provide a tactic to prevent the spread of virulent F. oxysporum f. sp. vasinfectum genotypes into uninfested areas through infected seed.

scholarly journals Bioactive Titanate Layers Formed on Titanium and Its Alloys by Simple Chemical and Heat Treatments

2015 ◽  
Vol 9 (1) ◽  
pp. 29-41 ◽  
Author(s):  
Tadashi Kokubo ◽  
Seiji Yamaguchi
Keyword(s):  
Sodium Titanate ◽  
Strong Acid ◽  
Heat Treatments ◽  
Calcium Titanate ◽  
Hot Water ◽  
Apatite Formation ◽  
Porous Ti ◽  
Artificial Hip Joint ◽  
Heat Treated ◽  
Naoh Treatment

To reveal general principles for obtaining bone-bonding bioactive metallic titanium, Ti metal was heat-treated after exposure to a solution with different pH. The material formed an apatite layer at its surface in simulated body fluid when heat-treated after exposure to a strong acid or alkali solution, because it formed a positively charged titanium oxide and negatively charged sodium titanate film on its surface, respectively. Such treated these Ti metals tightly bonded to living bone. Porous Ti metal heat-treated after exposure to an acidic solution exhibited not only osteoconductive, but also osteoinductive behavior. Porous Ti metal exposed to an alkaline solution also exhibits osteoconductivity as well as osteoinductivity, if it was subsequently subjected to acid and heat treatments. These acid and heat treatments were not effective for most Ti-based alloys. However, even those alloys exhibited apatite formation when they were subjected to acid and heat treatment after a NaOH treatment, since the alloying elements were removed from the surface by the latter. The NaOH and heat treatments were also not effective for Ti-Zr-Nb-Ta alloys. These alloys displayed apatite formation when subjected to CaCl2treatment after NaOH treatment, forming Ca-deficient calcium titanate at their surfaces after subsequent heat and hot water treatments. The bioactive Ti metal subjected to NaOH and heat treatments has been clinically used as an artificial hip joint material in Japan since 2007. A porous Ti metal subjected to NaOH, HCl and heat treatments has successfully undergone clinical trials as a spinal fusion device.

scholarly journals Reduction of Chilling Injury in Stored `Hass' Avocado Fruit by 38 °C Water Treatments

HortScience ◽  
1997 ◽  
Vol 32 (7) ◽  
pp. 1247-1251 ◽  
Author(s):  
Allan B. Woolf
Keyword(s):  
Electrolyte Leakage ◽  
Chilling Injury ◽  
Persea Americana ◽  
Hot Water ◽  
Skin Tissue ◽  
Heat Treated ◽  
Avocado Fruit ◽  
Temperature Damage ◽  
Hass Avocado ◽  
Water Treatments

`Hass' avocado (Persea americana Mill.) fruit were heat treated in water at 38 °C for 0 to 120 minutes, and stored at 0.5 °C for up to 28 days. After storage, fruit were ripened at 20 °C and their quality evaluated. External chilling injury (CI) developed during storage in nonheated fruit. Skin (exocarp) sectioning showed that browning developed from the base of the exocarp, and with longer storage, this browning moved outwards toward the epidermis. Longer durations of hot water treatment (HWT) progressively reduced CI; 60 minutes was the optimal duration that eliminated external CI, while best maintaining fruit quality. Concomitantly, electrolyte leakage of heated skin tissue increased ≈70% during storage, whereas electrolyte leakage of nonheated skin tissue increased ≈480% over the same period. Thus, significant protection was conferred by HWTs against low temperature damage to avocados and these effects are reflected in the morphology and physiology of the skin tissue.

scholarly journals Hot-water Dips Extend the Shelf Life of Fresh Broccoli

HortScience ◽  
1995 ◽  
Vol 30 (5) ◽  
pp. 1054-1057 ◽  
Author(s):  
Charles F. Forney
Keyword(s):  
Weight Loss ◽  
Relative Humidity ◽  
Effective Treatment ◽  
Water Loss ◽  
Hot Water ◽  
Odor Control ◽  
Delayed Senescence ◽  
Heat Treated ◽  
Water Treatments ◽  
Decay Development

Freshly harvested heads of `Cruiser' or `Paragon' broccoli (Brassica oleracea L. Italica group) were heated by immersing in water at 42, 45, 48, 50, or 52C. Immersion times were decreased as treatment temperatures were increased and ranged from 20 to 40 minutes at 42C to 1 to 3 minutes at 52C. Control heads, dipped in 25C water for 0, 10, or 40 minutes, began to turn yellow after ≈3 days storage at 20C and 80% to 90% relative humidity. Immersion in 42C water delayed yellowing by 1 or 2 days; immersion in 45, 48, 50, or 52C prevented yellowing for ≤7 days. Water loss of broccoli during storage at 20C increased by ≤1% per day by some hot-water treatments. Immersion in hot water decreased the incidence of decay during storage at 20C. Immersion in 50 or 52C water for 2 minutes was most effective in controlling decay development. Broccoli immersed in 52C water for 3 minutes had a distinct off-odor. Control and treated broccoli held at 0C for 8 days following hot-water dips were similar in quality. Yellowing of heat-treated broccoli was inhibited when broccoli was warmed to 20C following storage at 0C. Hot-water treatments also delayed senescence at 20C when broccoli was treated following 3 weeks of storage at 0C. Immersion of broccoli in 50C water for 2 minutes was the most effective treatment for reducing yellowing and decay while not inducing off-odors or accelerating weight loss.

Hot water dipping and low temperature storage of 'Eureka' lemons

1997 ◽  
Vol 37 (2) ◽  
pp. 249 ◽  
Author(s):  
R. L. McLauchlan ◽  
S. J. Underhill ◽  
J. M. Dahler ◽  
J. E. Giles
Keyword(s):  
Chilling Injury ◽  
Heat Treatments ◽  
Fruit Weight ◽  
Hot Water ◽  
Citrus Limon ◽  
Low Temperature Storage ◽  
Potential Control ◽  
Heat Treated ◽  
Low Incidence ◽  
Temperature Storage

Summary. Prestorage heat treatments at 47–53°C for 1–3 min were investigated as a potential control of chilling injury in cold disinfested ‘Eureka’ lemons (Citrus limon). Hot water dips significantly reduced the incidence of chilling injury in fruit stored at 1°C for 28 and 42 days. Storage at 1°C for 14 days resulted in comparatively minor chilling injury, so that hot water dips gave little additional benefit. This result is thought to reflect the low incidence of chilling injury, rather than the lack of effectiveness of heat treatments. Scald damage (surface browning) occurred after 3 min at 53°C. Heat treatments had no significant effect on the incidence of disease at all durations of storage. The rate of fruit weight loss during 7 days at 20°C after storage for 14, 28 or 42 days at 1°C was significantly lower in heat- treated fruit.

scholarly journals A comparison of postharvest quality of breadfruit (Artocarpus altilis) after disinfestation with hot air or hot water treatments

2019 ◽  
Vol 72 ◽  
pp. 67-74 ◽  
Author(s):  
Seeseei Molimau-Samasoni ◽  
Veronica Vaaiva ◽  
Semi Seruvakula ◽  
Angelika Tugaga ◽  
Guinevere Ortiz ◽  
...  
Keyword(s):  
Fruit Fly ◽  
Heat Treatments ◽  
The Body ◽  
Hot Water ◽  
Postharvest Quality ◽  
Heat Damage ◽  
Artocarpus Altilis ◽  
Hot Air ◽  
The Pacific ◽  
Water Treatments

Breadfruit from Samoa potentially host the Pacific fruit fly (Bactrocera xanthodes) and so their export to New Zealand requires a disinfestation treatment. Heat treatments by air (HAT) or water (HWT) are common fruit-fly disinfestation treatments for tropical crops. Two breadfruit cultivars – Puou and Ma’afala – were subjected to three heat treatments, HAT-1 (minimum 47.2oC for 20 min at core), HAT-2 (49.0oC for 100 min at core) and HWT (47.2oC for 20 min at core), and an untreated control was also included. Fruit were stored for one week at 15oC followed by three days at 25oC. Disorders observed were heat damage to the skin (blackening) and increased decay on the body and stem-end. Heat damage was at an acceptably low level following HAT-1 but was unacceptable following HAT-2 or HWT. Initial results suggest that a HAT can be tolerated, but the effect of ramp rate and the potential of using a two-step HWT system should be examined.

scholarly journals Finding A Fresh Carcass: Bacterially-Derived Volatiles And Burying Beetle Search Success

2020 ◽  
Author(s):  
Stephen T. Trumbo ◽  
Sandra Steiger
Keyword(s):  
Dimethyl Sulfide ◽  
A Priori ◽  
Dimethyl Disulfide ◽  
Antibacterial Treatment ◽  
Burying Beetle ◽  
Limited Ability ◽  
Remarkable Effect ◽  
Sulfur Containing ◽  
Methyl Thiocyanate ◽  
Sulfur Containing Compounds

AbstractWhen burying beetles first emerge as adults, they search for well-rotted carcasses with fly maggots on which to feed. After attaining reproductive competence, they switch their search and respond to a small, fresh carcass to prepare for their brood. Because the cues used to locate a feeding versus a breeding resource both originate from carrion, the beetles must respond to subtle changes in volatiles during decomposition. We investigated cues used to locate a fresh carcass in the field by (1) a general subtractive method, applying an antibacterial or antifungal to reduce volatiles, and (2) a specific additive method, placing chemicals near a fresh carcass. Five sulfur-containing compounds were studied: dimethyl sulfide (DMS), dimethyl disulfide (DMDS), dimethyl trisulfide (DMTS), methyl thiolacetate (MeSAc) and methyl thiocyanate (MeSCN). For the sulfides, we predicted that DMS would be the most attractive and DMTS the least attractive because of differences in the timing of peak production. We made no a priori predictions for MeSAc and MeSCN. Antibacterial treatment of a carcass aged for 48 h resulted in a 59% decrease in beetles discovering the resource. The addition of MsSAc had no effect on discovery of a fresh carcass, while DMS and DMDS had a limited ability to attract breeding beetles. The chemical that was least well known, MeSCN, had a remarkable effect, increasing beetle numbers by 200-800% on a fresh carcass and almost guaranteeing discovery. DMTS, which is known to attract a variety of carrion insects, was the only compound to significantly reduce beetle presence at a fresh carcass. A laboratory experiment demonstrated that DMTS does not directly inhibit breeding, suggesting that DMTS deters breeding beetles while they fly.

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