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Twelve tomato cultivars were evaluated during commercial juice production and storage for retention of betacarotene. Samples of fresh tomatoes, after extraction, pasteurization, canning, and after 7 months storage at 22°C were analyzed according to the AOAC methods (1980) for beta-carotene. There was a twofold difference in beta-carotene content between the highest and lowest cultivars in raw processed and stored product. A 20% loss of the beta-carotene content was observed during extraction and another 20% loss found after 7 months of storage. 相似文献
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Structural Collapse and Volatile Retention During Heating and Rehumidification of Freeze-Dried Tomato Juice 总被引:1,自引:0,他引:1
The effects of temperature, moisture content, and pectin addition on the “collapse” of freeze-dried tomato juice cake and retention of volatiles were investigated. High temperatures and high moisture contents induce collapse and the loss of volatiles, which was measured with 14C-labelled butyl acetate. The addition of pectin, which enhances the viscosity of the tomato juice, increases its “collapse” temperature after freeze-drying and the retention of volatiles. 相似文献
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ABSTRACT: The impact of label information on the liking and closeness to ideal of tomato juice beverages was examined by having 100 judges assess 3 tomato juice beverages (Campbell's tomato juice, V8 juice, and an experimental tomato juice enhanced with soy) either with or without labeling information. Judges rated overall liking of each product and then rated appropriateness of various attributes (saltiness, tomato flavor, thickness, texture, red color, orange color, and brown color) on 5-point just-right scales. Only half of the judges were presented with product-related label information during evaluation. Overall liking scores were analyzed using repeated-measures ANOVA, whereas different attribute ratings were analyzed using Thurstonian Ideal Point modeling and Chi-square. Product-associated label information did not significantly alter overall liking ratings ( P > 0.05), although a significant difference in liking was found between products ( P < 0.05). Similarly, the label information did not impact comparison of product attribute levels to ideal attribute levels. Both V8 and Campbell's were significantly different from the ideal for 3 of the attributes ( P < 0.05). For the soy-enhanced tomato juice, all 7 attributes were significantly different from the ideal ( P < 0.05). In this instance, labeling information had no notable impact on assessments. 相似文献
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热处理对荔枝果汁品质的影响 总被引:2,自引:0,他引:2
为探讨热处理对荔枝果汁品质的影响,将荔枝原果汁在60~100℃温度下进行热处理,测定果汁的褐变度、pH 值、固形物含量、化学成分(糖分、抗坏血酸、5- 羟甲基糠醛(5-HMF)、总酚)及挥发性风味成分等指标的变化。结果表明:荔枝果汁在0~60min 内褐变度的变化符合零级反应动力学模型。热处理过程中抗坏血酸和总酚含量下降明显,而糖含量变化不大,因此抗坏血酸降解和多酚聚合可能是影响荔枝果汁褐变的主要因素。热处理后荔枝果汁风味出现明显变化,采用顶空固相微萃取- 气相质谱对加热前后风味成分进行分析,发现低级醇和酯类含量明显下降,同时,产生了含硫化合物和高级醇等新物质。 相似文献
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Irene M. Caminiti Izabela Palgan Arantxa Mu?oz Francesco Noci Paul Whyte Desmond J. Morgan Denis A. Cronin James G. Lyng 《Food and Bioprocess Technology》2012,5(2):680-686
Non-thermal technologies such as UV irradiation can offer advantages for minimal processing of transparent beverages. In this
study, reconstituted apple juice was exposed to UV light in a continuous laboratory scale system at energy dosages ranging
from 2.66 to 53.10 J/cm2 by changing the exposure time. Treated juices were then evaluated for microbial inactivation and selected physical and chemical
attributes. Product quality was further assessed by sensory evaluation using a 30-member consumer panel. Microbiological analysis
was performed by inoculating apple juice with Escherichia coli K12 and Listeria innocua and microbial numbers were counted pre- and post-processing. UV energy levels did not affect pH, °Brix, or total phenols
content, but decreased non-enzymatic browning (p < 0.01) and antioxidant capacity (p < 0.05) compared to unprocessed juice. A colour-lightening effect was noted with increasing energy dose. All UV treatments
applied (2.66 J/cm2 and above) resulted in a reduction below the detection level (<1 log cfu/ml) for both E. coli and L. innocua in apple juice. Sensory evaluation showed that samples treated with energy dosages up to 10.62 J/cm2 were comparable to the control in terms of acceptability, though higher dosages produced adverse effects in terms of flavour
and colour. Based on these results, UV treatment with low energy dosages could represent a valid alternative to thermal processing
to eliminate pathogenic microorganisms while maintaining quality in reconstituted apple juice. 相似文献
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Supercritical Carbon Dioxide Effects on Some Quality Attributes of Single Strength Orange Juice 总被引:5,自引:0,他引:5
A.G. ARREOLA M.O. BALABAN M.R. MARSHALL A.J. PEPLOW C.I. WEI J.A. CORNELL 《Journal of food science》1991,56(4):1030-1033
Supercritical carbon dioxide treatment of orange juice (OJ) can inactivate pectinesterase (PE). Effects of such treatment on OJ quality and sensory attributes were investigated. Treatment pressures (7–34 MPa), temperatures (35–60°C), and times (15–180 min) were studied. Treatment did not significantly change pH and °Brix values; however, it stabilized and enhanced cloud, even in presence of active PE; color was improved, and total acidity slightly decreased. Ascorbic acid was lower in controls than in supercritically treated samples. Sensory evaluations showed color and cloudiness of treated juice were better than in untreated juice. Flavor, aroma and overall acceptability were not significantly affected. 相似文献
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以鲜榨樱桃番茄汁为原料,研究其分别经巴氏杀菌(85 ℃、15 min)和超声波杀菌(200 W、40 ℃、30 min)后的品质动力学变化。杀菌后的樱桃番茄汁分别贮藏在不同温度条件下(0、4、10、15、20 ℃),每隔一定时间测定其色泽、VC含量和菌落总数。结果表明:2 种杀菌方式后樱桃番茄汁的色泽随着贮藏时间的延长和贮藏温度的升高变化越明显;以VC含量变化为指标,在0~10 ℃条件下,超声波杀菌比巴氏杀菌的货架期延长了3.8~4 d;以菌落总数为评价指标,2 种杀菌方式的货架期差异不显著,菌落总数的变化符合一级反应模型,该模型可准确预测0~20 ℃各贮藏温度条件下的货架期。鲜榨樱桃番茄汁在0~10 ℃条件下贮藏,经超声波杀菌推荐货架期为6~9 d,经巴氏杀菌推荐货架期为6~8 d。 相似文献
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The formation of furan in freshly prepared apple and orange juices as affected by ionizing radiation and thermal treatments was studied using a newly developed solid‐phase microextraction method coupled with gas chromatography‐mass spectrometry (GC‐MS). Results show that furan levels increased linearly as radiation dose increased from 0 to 5 kGy. Irradiation induced more furan in apple juice than in orange juice. During post‐irradiation storage at 4 °C, furan levels increased in both apple and orange juices, particularly in the 1st 3 d. On the other hand, irradiation degraded deuterated furan (d4‐furan) spiked in water and fruit juices. The rate of degradation as a function of radiation dose was the highest in water and the lowest in orange juice. Submerging the juice samples in boiling water for 5 min induced higher amounts of furan in orange juice than in apple juice, but autoclaving (121 °C, 25 min) resulted in more furan formation in apple juice than in orange juice. Results reported here suggest that both ionizing radiation and thermal treatments induce furan formation in fruit juices. 相似文献
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S. M. Jafari S. S. Jabari D. Dehnad S. A. Shahidi 《Food and Bioprocess Technology》2017,10(2):307-316
In this research, our chief aim was to survey possible improvements in thermophysical properties of nanofluids when they are used as heating mediums for time reduction and energy saving in food industries for the first time. Accordingly, three different variables of temperature (70, 80, and 90 °C), alumina nanoparticle concentration (0, 2, and 4 %), and time (30, 60, and 90 s) were selected for thermal processing of tomato juice by a shell and tube heat exchanger. Our results revealed that incorporation of nanoparticles could raise density, viscosity, and thermal conductivity and decrease heat capacity, but this increasing/decreasing trend was linear or non-linear depending on the diameter of the nanoparticles. Four percent Al2O3–water, compared with 2 % nanofluid and pure water (0 % nanofluid), had the highest overall heat transfer coefficients for all Re numbers. Incorporating nanoparticles into the base heating fluid of water could augment the effectiveness of the heat exchanger by 49 %. Thermal processing time of tomato juice was shorter for 2 and 4 % nanofluids, compared with water, by 22.23 and 46.29 %, respectively; this time reduction caused energy saving rates for 2 and 4 % nanofluids to be improved by 22.3 and 48.76 %, respectively. 相似文献
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Acidification, addition of dimethyl dicarbonate and a mixture of potassium sorbate and sodium benzoate and storage temperature were related to microbiological stability and quality of tomato juice. Whether iuices were acidified CDH 4.0 to 3.7) or nonacidified. dimethyl dicarbonate and sorbate/benzoate were highly effective in diminishcng mold and yeast count at 5°C and 20°C. Dimethyl dicarbonate in juices acidified to pH 3.7 and stored at 5°C was most effective in controlling plate counts, followed by sorbate/benzoate in juices acidified to pH 3.7 and stored at 5°C and 20°C. Tomato juice treated with dimethyl dicarbonate had lower amounts of ascorbic acid, total amino acids, fructose, glucose, lycopene and β-carotene. 相似文献
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《International Journal of Food Properties》2013,16(1):89-99
Fruit bar was prepared from blend of ripe papaya and tomato pulps (variety, Red Lady and C.V. Naveen, respectively) in the ratio 75:25 on weight basis. Effects of hydrocolloids viz. pectin (P), starch (S), and ethyl cellulose (EC) and its three different levels on physico-chemical, sensory, and textural characteristics were investigated. It was found that seven different samples of fruit bar had moisture contents of 20.9–22.1% and total soluble solids 78.1–78.8°Brix while pH, browning index, and vitamin C contents were in the following ranges, 4.3–4.50, 0.137–0.150 (OD), and 40.5–41.4 mg/100 g respectively. Texture study revealed that hydrocolloids incorporation at 1% each of starch + ethyl cellulose and pectin + starch, 1.5% each caused significant (P < 0.05) increased in compactness/hardness of texture. Sensory characteristics study revealed that all the samples of fruit bar were acceptable in taste, color, and aroma but differed significantly (P < 0.05) in their texture. The samples packed in LDPE bags (100 μ), stored at 35–45°C for four months. It was found that there were significant (P < 0.05) changes in physico-chemical properties like acidity and vitamin C during four months storage. No significant (P < 0.05) effect on either browning index (OD) or deterioration in color, taste, and aroma of these samples was observed. During four months storage change in color and texture were not uniform for all treatments. Addition of 0.5 and 1% of each starch + ethyl cellulose were effective in maintaining the color while 0.5, 1, and 1.5% of each P + S was effective in improving the texture during four months storage. 相似文献
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A Continuous High-Pressure Carbon Dioxide System for Cloud and Quality Retention in Orange Juice 总被引:3,自引:0,他引:3
D. Kincal W.S. Hill M. Balaban K.M. Portier C.A. Sims C.I. Wei M.R. Marshall 《Journal of food science》2006,71(6):C338-C344
ABSTRACT: Orange juice (OJ) was treated with a continuous high-pressure carbon dioxide (HPCD) system, and the quality parameters pH, Brix, titratable acidity (TA), cloud, pectinesterase (PE) activity, color, and sensory attributes were determined. Treatment pressures were 38, 72, and 107 MPa, and CO2 /juice (w/w) ratios were from 0.40 to 1.18. Residence time was kept at 10 min. Cloud increased between 446% and 846% after treatments. There were no significant changes in pH and Brix (α= 0.05). TA of the treated juice was found to be significantly different from that of control (α= 0.01). PE was not completely inactivated. There was a small, but significant increase in juice L-value (α= 0.01) and a decrease in a-value for color. There was no significant change in b-values (α= 0.05). Statistical analysis for the sensory data showed no difference between fresh, frozen control juice and treated juice after 2 wk of refrigerated storage at 1.7 °C. 相似文献
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Fengyu Tang Yanshun Xu Qixing Jiang Wei Zhang Luyao Zhang 《International Journal of Food Properties》2013,16(8):1828-1840
In this study, a traditional Chinese dish, a ready-to-eat sweet and sour carp was developed. The effects of sterilization temperature (110, 115, 121, and 130°C) on the selected properties, including heat penetration characteristics, as well as rheological, instrumental color, texture, and sensory attributes, were investigated at the same lethality value (F0) of 4.5 min. The results showed that the heat penetration parameters of cooking value (C-value) and the ratio of C-value to F0 value (C-value/F0) exhibited an inverse relationship with processing temperature. The color and rheological properties of the sauce and the texture of the fish sterilized at 130°C were better preserved compared to those sterilized at other temperatures. The sensory attributes of the product sterilized at 130°C scored highest among the final products sterilized at the four temperatures. This study suggested that short-time sterilization at a high temperature can minimize the negative thermal impact on sweet and sour carp product, which would be feasible in the practical production. 相似文献
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气体二氧化氯对樱桃番茄贮藏品质的影响 总被引:1,自引:0,他引:1
以樱桃番茄为试材,研究10、20、40 g/m~3 ClO_2处理30 min后,10℃贮藏期间的品质变化。结果表明:20 g/m~3 ClO_2处理组综合评价好,贮藏15 d,腐烂率、失重率、可溶性固形物(TSS)、可滴定酸(TA)、V_C分别为27%、5.8%、13.9%、13.3%、29 mg/g FW,呼吸强度波动小,明显优于其他处理组。说明气体Cl O_2对樱桃番茄有一定保鲜效果,且20 g/m~3 Cl O_2处理效果最好。 相似文献
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超高压物理能对胡萝卜汁中类胡萝卜素异构体的影响 总被引:1,自引:0,他引:1
本实验研究了超高压处理对胡萝卜汁中类胡萝卜素异构体的作用,为利用超高压技术调控利于人体吸收的类胡萝卜素几何异构体奠定基础.胡萝卜汁分别进行100、300、500、700MPa处理5min,然后用C30柱加之二极管阵列检测器的HPLC分离检测样品中类胡萝卜素几何异构体.根据类胡萝卜素组分的色谱行为、光谱特征及Q值对其异构体进行定性,确定主要的类胡萝卜素有全反式β-胡萝卜素、15-顺-、13-顺-、9,15-顺-、9- 顺-β-胡萝卜素和全反式α-胡萝卜素等.结果表明,超高压处理可使能垒较低的9、13、15位等全反式类胡萝卜素发生部分顺式异构化或降解生成小分子片段. 相似文献