Effect Of Hot Water Treatment Research Articles

Effects of hot water treatments on the main physicochemical characteristics and the levels of vitamin C and polyphenols of two sweet cherry cultivars (Prunus avium L.) during cold storage and shelf-life

Effects of hot water treatments on the main physicochemical characteristics and the levels of vitamin C and polyphenols of two sweet cherry cultivars (Prunus avium L.) during cold storage and shelf-life

Effect of hot water treatments on physiological and biochemical changes in mango cv. Banganapalli during storage at ambient temperature

Effect of hot water treatments on physiological and biochemical changes in mango cv. Banganapalli during storage at ambient temperature

Effect of hot water treatment and Timorex Gold® in the control of avocado anthracnose

Effect of hot water treatment and Timorex Gold^® in the control of avocado anthracnose

Thermal softening kinetics of African black olive fruit: Influence of temperature and water absorption on the thermal maceration dynamics and thermophysical properties

Softening of the pulp of African black olive fruit (Canarium schweinfurthii) is one of the unit operations in the maceration and de-pulping process of the pulp for consumption or to produce masticatories or oil. The softening process is temperature-sensitive, and hot water treatments are applied arbitrarily by local processors that might result in the hardening instead of maceration or softening of the fruits. This study, therefore, investigates the effect of hot water treatment on the softening and maceration kinetics of the fruits at different temperatures. To achieve this, two varieties of the fruits were selected and immersed in a water bath at temperatures of 30–60°C. Some of the parameters determined were the moisture absorption rate, hardness ratio, dimensional changes, thermal properties, and softening kinetics. The results showed that the softening curves and kinetics were directly affected by the temperature of the hot water. Hardening of the pulp occurred at a hot water temperature of 60°C for the long variety. In contrast, softening did not take place at 30°C for both varieties. Maceration occurred at 40–50°C for the long variety and 40–60°C for the short variety. The maximum maceration rate was at 50°C with an average softening rate of 0.161 N/hr for long variety and the least rate was 0.0565 N/hr for 40°C short variety. The activation energy was 47.46 kJ/mol for the short variety and 48.06 kJ/mol for the long variety. All the properties were presented as a function of the temperature or moisture content with good results. The obtained data will be helpful in the scaling up of the de-pulping process of the fruit by developing processing equipment for large-scale industrial processing and also prevents hardening that can result in losses for small-scale processors who soften and sell the fruits as snacks. Novelty impact statement Several studies abound on African black olive (Elemi) but none is available on the processing dynamics of softening the pulp for de-pulping the fruits to produce masticatories or oil. A good number of these research focused on physical properties, biochemical contents, proximate composition, and other in vivo assessments. Therefore, the present study highlights the softening kinetics of the fruit during the maceration process. It showed that (1) hardening of the pulp occurs at 60°C while 30°C cannot cause maceration; (2) The maceration rate follows a three-period pseudo first-order kinetics; (3) Quicker maceration can be achieved at 50°C soaking water temperature.

Effects of hot water treatment to alleviate chilling injury and enhance phenolic metabolism in eggplant fruit during low temperature storage

Eggplant (Solanum melongena L.) fruit is highly perishable vegetable due to rapid quality deterioration when stored under ambient temperature. The current handling and storage temperatures, below optimum storage temperature (<10°C), extend the storage life, but chilling injury (CI) occurs after a longer storage. In this study, the effects of pre-storage hot water dipping at 45°C hot water for 10 min on alleviation of CI and enhancement of phenolic metabolism in cold stored eggplant fruit for 15 d were investigated. Fruit stored at 10°C showed no CI and maintained fruit quality, while non-treated fruits stored at 1°C indicated severe CI. Hot water treatment alleviated CI incidence and inhibited the increases in malondialdehyde and hydrogen peroxide levels, and enhanced phenolic metabolism by increases of total phenolic levels and phenylalanine ammonia-lyase activities compared with the non-treated fruits during storage at 1°C. These results indicate that the alleviation of CI in eggplant fruit by hot water treatment at 45°C for 10 min might be due to the increase of antioxidant activity by enhancement in phenolic metabolism.

The Efficacy of Hot Water Treatments Against Fusarium Fujikuroi: The Fungal Agent of Bakanae Disease

Rice is one of the most grown agricultural products in the world. It is the most preferred food item in the Turkish diet. One of the most important fungal diseases of rice is Bakanae disease. It is a seed-borne and complex disease caused by the Fusarium species. Fusarium fujikuroi is the most virulent and widespread species. The excessive use of fungicides has raised concerns such as a decrease in the fungicide sensitivity of F. fujikuroi in the world. For this reason, alternative methods are being investigated to control the disease. In this study, the therapeutic effect of hot water treatment on contaminated seeds was investigated. Trials were carried out under in vitro and in vivo conditions, to determine the effects of hot water treatment on the germination rate of rice seeds. Hot water treatments at 55 °C and 57 °C were the most effective treatments against pathogen. However, pathogen was not inhibited at 50 °C. The lowest disease severity was determined at 57 °C (2.5%) and this was followed by hot water treatments at 55 °C (22.33%) and 52 °C (77.30%) in vivo tests, respectively. No disease symptoms were observed in the negative control plants. According to evaluations, the disease incidence decreased when treatment temperature was increased, resulting in a slightly reduced germination rate.

Effect of hot water treatment and prochloraz on the postharvest quality of ‘Carabao’ mango

Effect of hot water treatment and prochloraz on the postharvest quality of ‘Carabao’ mango

The Combined Effect of Hot Water Treatment and Chitosan Coating on Mango (Mangifera indica L. cv. Kent) Fruits to Control Postharvest Deterioration and Increase Fruit Quality

The synergistic effect of dipping in 55 °C for 5 min of hot water (HW) and 1% chitosan coating during the storage of mango at 13 ± 0.5 °C and 85%–90% relative humidity for 28 days was investigated. The combined treatment significantly suppressed the fruit decay percentage compared with both the single treatment and the control. In addition, the specific activities of key plant defense-related enzymes, including peroxidase (POD) and catalase (CAT), markedly increased. The increase occurred in the pulp of the fruits treated with the combined treatment compared to those treated with HW or chitosan alone. While the control fruits showed the lowest values, the combination of pre-storage HW treatment and chitosan coating maintained higher values of flesh hue angle (h°), vitamin C content, membrane stability index (MSI) percentage, as well as lower weight loss compared with the untreated mango fruits. The combined treatment and chitosan treatment alone delayed fruit ripening by keeping fruit firmness, lessening the continuous increase of total soluble solids (TSS), and slowing the decrease in titratable acidity (TA). The results showed that the combined application of HW treatment and chitosan coating can be used as an effective strategy to suppress postharvest decay and improve the quality of mango fruits.

Effect of hot water treatment on ripening of tomato var. TA234 silenced with the TomLoxB gene

ABSTRACT The objective of this study was to evaluate the application of hot water treatment to tomato fruits (Solanum lycopersicum cv. TA234) genetically modified with silencing of the TomloxB gene. Unmodified and genetically modified tomato fruits were immersed in water at 40°C for 10, 20 and 30 seconds. Subsequently, fruits were stored at 25°C for 18 days. Physiology was assessed and electrolyte leakage, lipoxygenase and polygalacturonase activities were monitored. Treatment applied to the genetically modified tomatoes at 40°C for 30 seconds, resulted in slower ripening, decreased metabolic activity and maintained the attributes in optimal conditions for longer time, increased the postharvest life of the genetically modified tomatoes until 18 days. Lipoxygenase and polygalacturonase activities were partially inhibited.

Effect of hot water treatment and irradiation on physiological loss of weight of graded mango (Mangifera indica) cv Alphonso fruits at ambient and cold storage conditions

The present investigations were carried out to study the effect of hot water treatment and irradiation on physiological loss in weight of graded mango (Mangifera indica) cv Alphonso fruits at ambient and cold storage conditions. Treated fruits were stored at ambient temperature (28.6 to 31.8°C, 76% RH) whereas in cold storage were kept at (12 ± 2°C, 90% RH). Maximum PLW was recorded in treatment 100 per cent mature hot water treated irradiated fruits (16.59%) that was at par with 85 per cent mature hot water treated irradiated fruits (16.55%) and 75per cent mature hot water treated irradiated fruits (16.34%) and significant over rest of the treatments on 16th day of storage.

Antioxidative Responses to Pre-Storage Hot Water Treatment of Red Sweet Pepper (Capsicum annuum L.) Fruit during Cold Storage.

The effects of hot water treatments on antioxidant responses in red sweet pepper (Capsicum annuum L.) fruit during cold storage were investigated. Red sweet pepper fruits were treated with hot water at 55 °C for 1 (HWT-1 min), 3 (HWT-3 min), and 5 min (HWT-5 min) and stored at 10 °C for 4 weeks. The results indicated that HWT-1 min fruit showed less development of chilling injury (CI), electrolyte leakage, and weight loss. Excessive hot water treatment (3 and 5 min) caused cellular damage. Moreover, HWT-1 min slowed the production of hydrogen peroxide and malondialdehyde and promoted the ascorbate and glutathione contents for the duration of cold storage as compared to HWT-3 min, HWT-5 min, and control. HWT-1 min enhanced the ascorbate-glutathione cycle associated with ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase, but it was less effective in simulating catalase activity. Thus, HWT-1 min could induce CI tolerance in red sweet pepper fruit by activating the ascorbate-glutathione cycle via the increased activity of related enzymes and the enhanced antioxidant level.

Efecto de la inmersión en agua caliente sobre los huevos y larvas de Anastrepha grandis (Macquart, 1846) (Diptera: Tephritidae) “in vitro” y sobre calabaza (Cucurbita moschata Duchesne, 1786)

There are risks involved in the production and exportation of fruit fly hosts due to the possible spread of tephritid pests during distribution. Anastrepha grandis attacks cucurbit fruits and is considered an A1 quarantine pest in many countries. The objective of this study was to evaluate the effect of hot water treatment on the eggs and larvae of A. grandis in vitro, and on ‘Atlas’ squash (Cucurbita moschata). The eggs and third-instar larvae of A. grandis were exposed to hot water at temperatures of 42.0, 44.0, 46.0, 46.5, 47.0, 47.5, 48.0, 49.0 and 50.0 (± 0.5) °C for durations of 0 (control), 10, 20, 30 and 60 minutes. Water temperatures of at least 44 °C affected the in vitro larval eclosion of A. grandis during all exposure times. No adults were obtained when in vitro A. grandis larvae were treated at 49 °C and 50 °C at all exposure times and, 48 °C for 30 and 60 minutes. No adults were obtained when squashes infested with A. grandis eggs or larvae were treated at temperatures of 49 °C and 50 °C during any exposure time, as well as subjected to 48 °C for 20 minutes. Anastrepha grandis larvae were slightly more susceptible to hydrothermal treatment than eggs in squashes. Hot water treatment applies at a temperature of 48 °C for 20 minutes is an effective phytosanitary treatment for squashes cv. Atlas infested with eggs and larvae of A. grandis.

Effect of hot water treatment on postharvest control of Penicillium expansum and Botrytis cinerea of apples

ISHS V International Symposium on Postharvest Pathology: From Consumer to Laboratory-Sustainable Approaches to Managing Postharvest Pathogens Effect of hot water treatment on postharvest control of Penicillium expansum and Botrytis cinerea of apples

The effect of hot water treatment on the storage ability improvement of fresh-cut Chinese cabbage

Fresh-cut Chinese cabbage (Brassica rapa ssp. pekinensis) was subjected to hot water treatment (HWT) at different temperatures (38–57°C) and duration (3 s – 20 min.), followed by ambient air cooling. After treatment, the cabbage was stored at different temperatures: 0°C, 5°C and 15°C. Fresh-cut cabbage (untreated) served as the control object. During storage, quality assessments and sensory evaluation were performed. Additionally, nutrient content and microbial contamination were determined. Chinese cabbage responded in a variety of ways to hot water treatment. Positive and stable reactions were obtained for cabbage after short treatment in a water bath at 53°C and 55°C for 3 s. These treatments delayed unfavourable quality alterations of fresh-cut cabbage, such as cut surface browning and rotting of leaf pieces at all storage temperatures. The development of off-odors and off-tastes was significantly inhibited in cabbage after HWT and short storage at 15°C. In general, the treatments did not influence the nutritional value of the cabbage. The concentrations of ascorbic acid, total sugars, soluble phenols and antiradical activity did not differ significantly in treated and non-treated material. Only the content of nitrates in cabbage stored at 15°C decreased significantly in all objects and the lowest amount was found for cabbage dipped in tap water.The intensive multiplication of yeasts and coliforms was noticed on fresh-cut Chinese cabbage after 3 days of storage at 15°C. A lower storage temperature (0°C) significantly inhibited microbial development in the cabbage, and especially yeasts and coliforms. The dipping of cut cabbage in tap water had no significant effect on the number of yeasts and coliforms, but increased mesophilic bacteria and Enterobacteriaceae compared to cut, untreated cabbage. HWT at 53°C and 55°C decreased the number of Enterobacteriaceae over 7 days of storage at 5°C.

EFFECT OF HOT WATER TREATMENT WITH CALCIUM DIPS ON POSTHARVEST QUALITY OF TOMATO

&#x0D; Tomato is fruit vegetables sustaining valuable benefits in economy and nutrition. It has a high content of Vitamin C and lycopene. Being a climacteric fruit, tomato is perishable and has a short shelf life. To improve the storage quality of tomato, the effect of hot water treatment and calcium dips on tomato (Solanum lycopersicum) was studied. Tomato fruits were dipped in two temperatures (40°C and 50°C) of the hot water bath for 2 minutes before treatment of 2% calcium chloride for 2 minutes. The fruits were stored at 10°C ± 2°C in the cold room at a relative humidity of 80-95%. Changes in weight loss, firmness, total soluble solids (TSS), titratable acidity, ascorbic acid, and lycopene content were observed and recorded on 0, 2, 4, 6, 8, 10, 12, 14 days of storage. Hot water treatment at 50°C with 2% of calcium chloride can control the weight loss and firmness of tomato with the low level of total soluble solids and acidity and retained the level of ascorbic acid. This treatment prone to extend shelf life, delay ripening and retained the postharvest quality of tomato.

Alternative postharvest pre-treatment strategies for quality and microbial safety of ‘Granny Smith’ apple

Over the years, chemical pre-treatments have been used intensively to maintain apple quality and reduce decay during postharvest. This conduct has been reported to have a negative impact on environment and human health. This study aimed to investigate alternative approaches such as hot water (HW) and electrolyzed water (WE) treatments for decay management of ‘Granny Smith’ apples. Two different sets of experiments were set up for this study. In experiment 1, the effects of HW treatment (45 °C) under varying dipping durations (5, 10 and 15 min) on physicochemical quality of apple were investigated. In experiment 2, the curative efficacy of slightly alkaline electrolyzed water (SAl-EW) (50, 100, 200, 300, 400 and 500 mg L−1) against Botrytis cinerea was investigated. Hot water treatment duration (15 min) had beneficial effects on flesh firmness, fruit colour, total soluble solid (TSS) and titritable acidity (TA) by the end of the storage. In contrast, a significant reduction in fruit weight and TA values (p < 0.05) were observed in control fruit. The SAl-EW treatments against B. cinerea resulted in a significant reduction in lesion zones compared to the untreated control fruit. Curative efficacy was most effective at concentrations of 200–500 mg L−1 for 5 °C and 300–500 mg L−1 for 24 °C. These findings suggest the potential of combining lower concentrations of SAl-EW with other hurdle techniques for better preservation of fresh apples.

Effect of Hot Water Treatment with Organic Additives in Fresh Cut Carrot

Fresh cut carrot (Daucus carota L.) slices were treated with hot (60°C) water and hot aqueous solution (2% sodium chloride, 2% citric acid and 10% lime juice) for 1 min and then surface water was removed. Following treatment, fresh-cut carrot slices were kept in a polypropylene (PP) box and stored in a refrigerator (4±1°C and 50±5% RH) for 12 days. The effectiveness of the treatments in extending shelf life was evaluated by determining respiration rate, firmness, weight loss, external colour, whiteness index (WI), some chemical parameters (ascorbic acid content, TSS, acidity, pH, total sugar, reducing sugar and beta carotene), total bacterial count (TBC) and sensory quality. The highest increment of WI (48.4%) was observed without heat-treated carrot slices. On the other hand, WI was increased by 12.1% and 21.7% in carrot slices treated with hot aqueous solution of 2% citric acid and with hot aqueous solution of 2% sodium chloride respectively at 12 days of storage. On the 12th day of storage, fresh-cut carrot treated with hot aqueous solution of 2% citric acid scored 7.3 and the rest of the sample scored less than 4.5 (indicate as unacceptable) in overall acceptability. Carrot slices treated with hot aqueous solution of 2% citric acid and 2% sodium chloride retained a minimum number of TBC and delayed changes in WI, external colour and beta carotene content compared to without heat-treated carrot slices. Keywords: Citric acid, respiration rate, sensory quality, sodium chloride, total bacterial count, whiteness index

Effects of hot water treatments and organic extracts on diseases, shelf life and quality of banana

Effects of hot water treatments and organic extracts on diseases, shelf life and quality of banana

The effect of hot water treatment on the properties of lotus leaves, reed leaves, and basho leaves combined with gelatin composites

This study investigated the feasibility of preparing biodegradable composites, such as food packing materials, from plant leaves as a substitute plastic. Lotus leaves, reed leaves, and basho leaves were treated with hot water and combined with gelatin to form composite samples. The effects on the morphology, thermal properties of leaves, and the mechanical properties and moisture absorption of the composites were studied. The Fourier-transform infrared spectroscopy (FTIR) analysis showed that the amorphous components such as lignin, wax, and pectin were removed after the hot water treatment. The treatment had the most beneficial effect on the reed leaf. The reed/gelatin composites had the best mechanical properties, of which the tensile strength and the flexural strength were 14.0% and 77.1%, respectively, higher than that of the lotus/gelatin composites and 121.5% and 192.5%, respectively, higher than that of the basho/gelatin composites. The morphology of the cross-section of the composites showed that there were numerous holes and gaps in the basho/gelatin composites which induced a high moisture absorption performance.

Simultaneous effects of hot water treatment with calcium and salicylic acid on shelf life and qualitative characteristics of strawberry during refrigerated storage

Simultaneous effects of hot water treatment with calcium and salicylic acid on shelf life and qualitative characteristics of strawberry during refrigerated storage