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1.
The efficiency of high hydrostatic pressure (HHP) with the combination of mild heat treatment on peroxidase (POD) and lipoxygenase (LOX) inactivation in carrots, green beans, and green peas was investigated. In the first part of the study, the samples were pressurized under 250–450 MPa at 20–50 °C for 15–60 min. In the second part, two steps treatments were performed as water blanching at 40–70 °C for 15 and 30 min after pressurization at 250 MPa and 20 °C for 15–60 min. Carrot POD was decreased to 16% residual activity within the first 30 min at a treatment condition of 350 MPa and 20 °C and then it decreased to 9% at 60 min. When the carrots were water blanched at 50 °C for 30 min after HHP treatment of 250 MPa at 20 °C for 15 min, 13% residual POD activity was obtained. For green beans, the most effective results were obtained by two steps treatment and approximately 25% residual POD activity was obtained by water blanching at 50 °C for 15 min after pressurization at 250 MPa and 20 °C for 60 min. An effective inactivation of POD in green peas was not obtained. For carrots, LOX activity could not be measured due to very low LOX activity or the presence of strong antioxidants such as carotenoids. After pressurization at 250 MPa and 20 °C for 15 or 30 min, water blanching at 60 °C for 30 min provided 2–3% residual LOX activity in green beans. The treatment of 250 MPa for 30 min and then water blanching at 50 °C for 30 min provided 70% LOX inactivation in green peas. 相似文献
2.
Effect of high hydrostatic pressure and temperature on carrot peroxidase inactivation 总被引:3,自引:0,他引:3
The combined effects of pressure and temperature on the activity of carrot peroxidase (POD) were investigated in the pressure range 0.1–600 MPa and the temperature range 25–45 °C. At lower pressures (<396 MPa), carrot POD stability increased compared to unpressurized samples. Inactivation of 91% was obtained at 600 MPa and 45 °C. High hydrostatic pressure (HHP) combined with temperature treatment enhanced the inactivation of carrot POD. Regeneration of POD activity with the combined HHP and temperature treatments followed first order kinetics at 25, 35 and 40 °C. Regeneration was not observed at 506 MPa and 45 °C. HHP had no significant effect on the loss of vitamin C or on protein content. HHP combined with mild heat treatment was found to be better than the thermal treatment at high temperatures for inactivation of POD in carrot processing. 相似文献
3.
Muhammad Abid Saqib Jabbar Bing Hu Malik Muhammad Hashim Tao Wu Zhongwei Wu Muhammad Ammar Khan Xiaoxiong Zeng 《LWT》2014
The combination of innovative, non-thermal technologies for the production of safe and quality fruit juices is a recent trend in food processing. The purpose of this study was to evaluate the effects of combined treatment of ultrasound (US) and high hydrostatic pressure (HHP) on enzymes (polyphenolase, peroxidase and pectinmethylesterase), microorganisms (total plate counts, yeasts and molds) and phenolic compounds (total phenols, flavonoids and flavonols) of apple juice. Moreover, its effects on ascorbic acid, antioxidant capacity and DPPH free radical scavenging activity, color values, pH, soluble solids and titratable acidity were investigated. Fresh apple juice was treated with US (25 kHz and 70% amplitude) at 20 °C for 60 min with subsequent HHP treatment at 250, 350 and 450 MPa for 10 min at room temperature. The results revealed that the combined US-HHP450 treatment caused highest inactivation of enzymes with complete inactivation of total plate counts, yeasts and molds. It also significantly improved the phenolic compounds, ascorbic acid, antioxidant capacity, DPPH free radical scavenging activity and color values. The present results suggest that the combination of US and HHP can act as a potential hurdle to produce safe and high quality apple juice with reduced enzymes and microbial activity and improved nutrition. 相似文献
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Antonio Vega-Gálvez Elsa Uribe Gipsy Tabilo-Munizaga Purificación Garcia-Segovia Karina Di Scala 《LWT》2011,44(2):384-391
The effect of High Hydrostatic Pressure (HHP) and other pretreatments on the drying kinetics, antioxidant activity, firmness and microstructure of Aloe vera gel was investigated during convective drying at 70 °C. The pretreatments analyzed were high hydrostatic pressure, blanching, enzymatic and microwaves. Simulation of drying curves was studied through the application of several mathematical models such as Newton, Henderson and Pabis, Page, Modified Page, Wang and Singh, and Weibull. Among them, the Weibull model provided the best fit for the experimental data. All pretreatments increased the water diffusion coefficient compared to the control sample. Microwaves followed by HHP presented the fastest drying rates. All pretreatments modified the microstructure and hence the texture of the product. HHP and microwaves increased firmness while blanching and enzymatic treatments produced a softer final product. Blanching, microwaves and HHP enhanced A. vera antioxidant activity. However, the HHP pretreated samples showed the highest antioxidant activity compared to the rest. Based on these results, HHP together with convective drying offers the chance of producing dried aloe with high antioxidant attributes. 相似文献
6.
Bing Hu Malik Muhammad Hashim Muhammad Saeeduddin Shicheng Lei Tao Wu Xiaoxiong Zeng 《International Journal of Food Science & Technology》2014,49(11):2449-2457
The combined effects of ultrasound (US) and high hydrostatic pressure (HHP) on enzymes, micro‐organisms, colouring pigments, total polyphenols, ascorbic acid and physicochemical properties of carrot juice were investigated. Carrot juice was treated with sonication (20 kHz, 70% amplitude) and HHP (250, 350, 450 MPa) at room temperature for 10 min. For comparison, fresh carrots were water blanched (WB) at 100 °C for 4 min and carrot juice was then extracted. As results, highest improvements in colouring pigments were observed in WB and US‐HHP450 treatments, which also completely inactivated micro‐organisms. The highest reduction in enzymes was observed in WB treatment followed by US‐HHP450. Total polyphenol contents increased significantly in US, HHP and US‐HHP treatments with the highest increase in US‐HHP450, but it decreased significantly in WB treatment. Ascorbic acid contents significantly decreased in WB and HHP450, while increased in US and US‐HHP treatments. Results indicate that US‐HHP450 treatment improves the quality of carrot juice and serves as a good alternative for blanching treatment. 相似文献
7.
Vilbett Briones-Labarca Gabriela Venegas-Cubillos Susana Ortiz-Portilla Marcelo Chacana-Ojeda Hector Maureira 《Food chemistry》2011
The aim of this work was to study the effect of high hydrostatic pressure on the bioaccessibility of specific nutrients (antioxidant, minerals and starch) in apple and to establish processing conditions that maximise the health benefits. The apple was pressurised at 500 MPa during 2, 4, 8 and 10 min. The antioxidant activity, mineral and starch content and bioaccessibility of apple samples were significantly affected by the processing and digestion conditions. Therefore, these results indicated that in vitro digestion has a noticeable effect on the antioxidant concentration, IC50, with much lower values (a smaller IC50 value corresponds to a higher antioxidant activity) of apple samples compared with those untreated and non-digestion. Apple has the highest calcium content (30.33 ± 1.94 mg/100 g), iron (14.46 ± 3.49 mg/100 g) and zinc (6.22 ± 0.91 mg/100 g). High hydrostatic pressure increased the mineral contents availability by 2.11–303.00% for calcium, 4.63–10.93% for iron and 8.68–28.93% for zinc. The dialysability and solubility of calcium, iron and zinc with respect to the values for the untreated sample were reduced by this high pressure technique. Consumption of apple under high hydrostatic pressure may supply substantial antioxidants, mineral and starch, which may provide health promoting and disease preventing effects. 相似文献
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Thermal processing for food preservation results in undesired softening of fruits and vegetables. To explore the potential of high pressure sterilization in food processing, the effects of combined high pressure/high temperature (HP/HT) treatments on carrot pectic polysaccharides and the related textural properties were investigated and compared with that of samples thermally processed at atmospheric pressure. Disks of fresh carrot (Daucus carota var. Yukon) tissue were subjected to three different treatments (80 °C–0.1 MPa, 100 °C–0.1 MPa and 80 °C–600 MPa) for varying time intervals. Subsequently, the residual texture and microstructural changes of the carrots were evaluated. Alcohol-insoluble residues were prepared from the samples and sequentially fractionated with water, cyclohexane-trans-1,2-diamine tetra-acetic acid (CDTA) and Na2CO3 solutions. Thermal treatments at 0.1 MPa caused extensive tissue softening. This was marked by increased cell separation, an increase in water soluble pectin (WSP) paralleled by a decrease in chelator (CSP) and sodium carbonate (NSP) soluble pectin. HP/HT treated carrots showed minimal softening and negligible changes in intercellular adhesion. This was accompanied by a significant reduction in the degree of methyl esterification of pectin, low WSP in contrast to the high CSP and NSP fractions, minor changes in the different pectin fractions during treatment, and a substantial amount of pectin in the fractionation residue. There was a clear difference between HP/HT and thermally processed carrot pectin; HP/HT showing pronounced texture preservation. 相似文献
10.
Taner Baysal Filiz Icier Seda Ersus Hasan Yıldız 《European Food Research and Technology》2003,218(1):68-73
The effects of microwave and infrared drying on the quality of carrot and garlic were studied and compared with the effects of conventional hot air (tray drier for carrot and fluid bed drier for garlic) drying. The quality of carrot and garlic were evaluated by instrumental and sensory analysis. Rehydration, moisture content, water activity, particle density, bulk density, porosity and colour values were obtained for microwave, infrared and hot-air dried vegetables. In addition, total moisture content versus time was represented by drying rate curves of carrot and garlic samples. Finally, free moisture content versus drying rate were compared for the three different drying methods. 相似文献
11.
Shrinkage, vitamin C degradation and aroma losses during infra-red drying of apple slices 总被引:1,自引:0,他引:1
The goal of this study was to determine the effect of drying temperature on the shrinkage, ascorbic acid (vitamin C) degradation and aroma retention of apples. Apple samples were found to shrink continuously until a water content value of 2 kg/kg d.b. The degradation of ascorbic acid followed a pseudo-first-order reaction and the degradation rate constant increased when temperature increased from 40 to 70 °C. The loss of aroma volatiles increased with temperature and drying time. 相似文献
12.
High hydrostatic pressure (HHP) treatments (singly or in combination with natural antimicrobials) were tested for stabilization of Manzanilla Aloreña seasoned olives stored at 25 °C. HHP (5 min) was highly effective on yeast populations at 300 MPa or higher. No viable yeasts were detected in samples treated at 400 MPa for up to three months. Low levels of endospore-forming bacteria were always detected after HHP treatments. Addition of nisin to the brines reduced bacterial counts by 1.4 log cycles but it had no effect on yeasts when tested singly or in combination with HHP treatment (400 MPa, 5 min). Thyme oil had almost no effect on yeast concentrations, but rosemary oil reduced yeast viable counts progressively during storage. Essential oils in combination with HHP (400 MPa, 5 min) significantly (p < 0.05) reduced the concentrations of aerobic mesophilic bacteria. Low-salt brined olives purged with N2 or supplemented with ascorbic acid and then pressurized for 5 min at 450 or 550 MPa were preserved for up to 5 months without spoilage, suggesting that the NaCl content in brines of packed Manzanilla Aloreña table olives could be reduced considerably by application of HHP as a stabilization treatment. 相似文献
13.
The paper aims at investigating the potential application of non-thermal innovative technologies, such as high hydrostatic pressure, for the sanitization of functional liquid foodstuffs. A 100% pomegranate juice was selected for the experiments, due to its high bioactive compounds content. The operating pressure, temperature and holding times at the pressure set point were changed over a wide range, with the aim of optimizing the processing condition in order to assure the microbiological stability of the processed juice as well as preserve the natural content of the functional compounds. The experiments clearly demonstrate that the high pressure treatment at room temperature improves the quality of pomegranate juice, increasing the intensity of red color of the fresh juice and preserving the content of natural anthocyanins. The residual activity of some enzymes at the end of high pressure processing, independently on the processing conditions, such as the polyphenoloxidase (PPO), causes the degradation of the nutraceutical compounds as observed in particular processing conditions, thus suggesting that the optimal combination of the processing parameters should take into account the degradation of the anthocyanins as well as the enzymatic activity. 相似文献
14.
The effect of high hydrostatic pressure on the microbiological quality and safety of carrot juice during refrigerated storage 总被引:1,自引:0,他引:1
The microbial quality of untreated and pressure-treated carrot juice was compared during storage at 4, 8 and 12 °C. High pressure treatment at 500 MPa and 600 MPa (1 min/20 °C) reduced the total counts by approximately 4 log CFU ml−1 and there was very little growth of the survivors during storage at 4 °C for up to 22 days. Total counts increased during storage of pressure-treated juice at 8 °C and 12 °C but took significantly longer to reach maximum levels compared to the untreated juice. The microflora in the untreated juice consisted predominantly of Gram-negative bacteria, identified as mostly Pantoea spp., Erwinia spp. and Pseudomonas spp. Initially the pressure-treated juice contained low numbers of spore-forming bacteria (Bacillus spp. and Paenibacillus spp.) and Gram-positive cocci; the spore-formers continued to dominate during storage. 相似文献
15.
We investigated the influence of pH and osmolarity on the high-pressure-induced gelatinization of waxy corn and waxy rice starches in salt solutions, and the properties of the resulting gels. Gelatinization kinetics, the gel swelling power of starches, their structure and their rheological properties were studied for starch suspensions treated at 500 MPa. Gelatinization took place mostly in the first 15 min of the pressure treatment and both the gelatinization speed and the maximal level of gelatinized starch decreased with increasing osmolarity. pH had a minor influence on gelatinization kinetics differing from one starch to another. The resulting gels appeared as a mix of a gel and starch granules with a higher proportion of native granules with increasing osmolarity. Gel strength and swelling were positively correlated to their proportion of gelatinized starch. Thus, gels with different structures and gelatinization levels can be obtained under pressure depending on pH and osmolarity. 相似文献
16.
The binding extent of odorant mixtures from aqueous suspensions by native, high pressure-treated starches and starch cryotexturizates was studied using capillary gas chromatography. The materials were corn, sorghum and amaranth starches. The native and high pressure-treated (650 MPa/9 min) starches were mixed with odorants and incubated (24 h) at room temperature. To obtain the cryotexturizate-odorant product, starch gels were frozen with odorants (−24 °C), stored (48 h) and thawed. Terpene hydrocarbons were strongly bound from the mixture by all the starches analyzed. The nonpolar molecules of terpene hydrocarbons modified the nature of hydrophobic binding sites in starch which in turn affected binding affinity of alcohols, ketones and phenols to the preparations. The competition effect between odorants for the binding sites was found. The varied ability of starch preparations to bind odorants was also related to the granule morphology and alteration in their structure upon treatment used. 相似文献
17.
Microbiological food safety assessment of high hydrostatic pressure processing: A review 总被引:1,自引:0,他引:1
High hydrostatic pressure (HHP) processing as a novel non-thermal method has shown great potential in producing microbiologically safer products while maintaining the natural characteristics of the food items. Scientific research of the process and its industrial applications has been widespread in the past two decades with many scientific publications describing its uses, advantages and limitations. The review describes the effect of HHP on foodborne pathogenic microorganisms, their structures and adaptive mechanisms, the intrinsic and extrinsic factors that affect its application with a focus on microbiological safety, and research needs. In a risk assessment context, tools and mechanisms in place to monitorize, optimize and validate the process, and procedures for assessing and modelling the lethal effect of the treatment are reviewed. 相似文献
18.
Effect of high hydrostatic pressure on antimicrobial activity and quality of Manuka honey 总被引:1,自引:0,他引:1
The antimicrobial activity of Manuka honey is of major interest to beekeepers and the honey industry. In this study, the effect of high hydrostatic pressure and thermal treatments on antimicrobial activity and quality parameters (principally, diastase number and hydroxymethylfurfural levels (HMF)) of Manuka honey were investigated. The honey was subjected to different pressures (100-800MPa) at 25°C for a range of holding times (15-120min). The antimicrobial activity was found to increase with applied pressure for a given holding time, while the diastase number and HMF levels remained, more or less, unaffected. The percentage inhibition in microbial growth correlated linearly (R(2)=0.94) with methyglyoxal concentration in the honey after treatment over the entire range of pressure, temperature and holding times studied. Maximum percentage inhibition (78.83%) was achieved when honey was subjected to 800MPa compared to the control (57.93%). Thermal treatments at higher temperatures were found to have a detrimental effect on antimicrobial activity based on percentage inhibition as well as methylglyoxal content. Thus, it can be concluded that the levels of methylglyoxal, and therefore the antimicrobial effect of Manuka honey, can be enhanced by using high pressure processing without adversely affecting honey quality. 相似文献
19.
Derek F. Keenan Nigel Brunton Francis Butler Rudy Wouters Ronan Gormley 《Innovative Food Science and Emerging Technologies》2011,12(3):261-268
The effects of high hydrostatic pressure (500 MPa/1.5 min/20 °C) and mild conventional pasteurization (P90 > 10 min) processing on the fructan content, polyphenolic stability and physico-chemical characteristics of apple purees enriched with two commercial prebiotics [Beneo GR® (inulin) and HSI® (fructooligosaccharides—FOS)] over 30 days at 4 °C were evaluated. Fructan analysis showed that the prebiotics were stable throughout 30 days and were present in sufficient quantities to deliver a prebiotic effect. Fluctuations in physico-chemical characteristics were more evident in purees containing inulin than FOS. Sensory acceptability of purees was deemed acceptable (> 3) by panellists and showed no preference for either processing type. Minor deterioration in acceptability was observed in thermal processed samples containing inulin inclusions during storage (p < 0.05). Processing reduced (p < 0.05) the levels of some polyphenolic compounds in all samples compared to unprocessed controls, in particular chlorogenic acid and phloridzin, which were largely responsible for overall decreases in total phenolic index (TPI).
Industrial relevance
Studies have shown that high hydrostatic pressure processing (HHP) can better retain inherent functional components i.e. antioxidant compounds, compared to mild pasteurization. However, processors need to be assured that further additions of functionally beneficial components, such as prebiotics, are similarly protected. This study focussed primarily on assessing the effect of thermal and HHP on the stability of two prebiotics over storage (30 days at 4 °C). Results indicate that both prebiotics were stable and present in sufficient quantities to deliver a prebiotic effect for both processing types after storage. In some cases, less hydrolysis of the prebiotic occurred in HHP purees. These outcomes could help the food industry identify the optimal processing type to maximise retention of added and inherent functional properties. 相似文献20.
The effects of a high hydrostatic pressure (HHP) treatment (450MPa, 15min at 20°C) on both the microbiological quality and the functional properties of plasma from biopreserved porcine blood were evaluated. Blood was inoculated with Enterococcus raffinosus-PS99 (10(7)ufcmL(-1)) and stored at 5°C. After 72-h storage, bacterial counts in inoculated samples decreased by 52, 70, 81 and more than 99% for coliforms, Pseudomonas spp, hemolytic and proteolytic bacteria, respectively. Counts of these bacterial groups were undetectable in the final product after pressurization, whereas total lactic acid bacteria were detected at levels up to 10(2)ufcmL(-1). Gelling, foaming and emulsifying properties of the plasma proteins were not noticeably affected by HHP. The results show that it is possible to obtain high-quality and microbiologically stable blood derivatives as functional ingredients, by combining biopreservation and HHP. 相似文献