Oxidative Stability of Soybean Triacylglycerol Using Carotenoids and Y-Tocopherol

The effect of lycopene, β-carotene, and γ-tocopherol on the oxidative stability of soybean triacylglycerol was evaluated under Schaal oven conditions at 60°C. Peroxide value, conjugated diene, hydroperoxides, and thiobarbituric acid reactive substances were used as indicators for primary and secondary lipid oxidation products, whereas Rancimat method was used to study the oil stability. Results indicated that lycopene and β-carotene acted as pro-oxidants, whereas γ-tocopherol acted as antioxidant in triacylglycerol. Pro-oxidative activity of lycopene was higher than β-carotene at 100 and 200 ppm levels under Schaal oven thermal conditions. The combination of lycopene and γ-tocopherol (1:2) acted as antioxidant with better efficiency than γ-tocopherol alone in inhibiting the hydroperoxide formation in triacylglycerols.     

D-最优混料设计优化复合果蔬酒配方

为丰富果蔬产品种类,提高其经济价值,采用番茄、红葡萄柚、番石榴和西瓜为原料,以感官评分与番茄红素含量为评价指标并利用模糊数学感官评价和D-最优混料设计,优化复合果蔬酒的原料配比。结果表明,将26.7%番茄汁、27.2%红葡萄柚汁、10.0%番石榴汁、36.1%西瓜汁进行混合后,采用复合果酒的酿造工艺,可获得色泽红亮透明、果香与酒香浓郁、滋味醇和,感官评分与番茄红素含量分别为94.1±1.3与(17.45±0.86)μg/mL的复合果蔬酒,其各项理化指标均符合QB/T 5476—2020《果酒通用技术》要求。     

Partial dehydration of cherry tomato at different temperature, and nutritional quality of the products

This study concerns the partial dehydration of cherry tomatoes (Lycopersicon esculentum, var. Shiren) to obtain a product with 25% initial water content. Two kinds of dried tomatoes were obtained using a forced air oven at 40, 60 and 80 °C for different lengths of treatment. The first type was dehydrated after immersion of the fresh tomatoes in an aqueous solution of citric acid, sodium and calcium chloride (10:10:24 g/l); the second was obtained with no pre-treatment. The products were characterised by measuring their CIE L*a*b* colour parameters and levels of l-ascorbic acid, lycopene and β-carotene to evaluate thermal damage during processing under the different conditions. Moreover, water activity and the formation of 5-hydroxymethylfurfural were also determined as an index of sugar heat degradation. Treatment with a dipping solution protected both the nutritional and chemical qualities of the partially dried cherry tomatoes. Temperature was directly related to browning, ascorbic acid loss and HMF formation, while no clear influence could be found for carotenoid degradation.     

The Effects of Genetic Transformation of Tomato with Antisense Phospholipase D cDNA on the Quality Characteristics of Fruits and Their Processed Products

The physico-chemical characteristics of tomato juice and sauce, prepared from transgenic tomato fruits (Lycopersicon esculentum Mill, var. Celebrity) transformed with an antisense phospholipase D (PLD) cDNA construct, were evaluated. The antisense transformation resulted in a 30-40% reduction of PLD activity in ripe fruits. The transgenic fruits were firmer, possessed better red color, and flavor. The juice and sauce preparations from transgenic fruits showed improved red color, lycopene content, Brookfield viscosity, and increased levels of major flavor volatiles such as hexenal. The dry matter and ash contents, as well as the precipitate weight ratio (PPT) of the transgenic fruit products were significantly higher when compared to the products from control fruits. The vitamin C content of the transgenic fruits was also higher as compared to the control fruits. The results suggest that a reduction in PLD activity may lead to increased membrane stability and preservation of membrane compartmentalization that can have positive quality impacts in transgenic fruits and their products.     

Changes in the carotenoid concentration in human postprandial chylomicron and antioxidant effect in HepG2 caused by differently processed fruit and vegetable soups

Ten subjects consumed one serving of an optimised or a reference soup produced using modified or traditional processing methods, respectively. Both soups contained the same proportions of carrot, tomato and broccoli, but with 5% olive oil in the optimised soup and 2.5% in the reference soup. The β-carotene content in 600 mL of the optimised/reference soups was 4.10/2.90 mg, and the lycopene content was 3.90/2.71 mg. The β-carotene and lycopene concentrations in chylomicrons isolated from blood serum samples were similar for both groups. Only 50% of subjects could be considered as carotenoid responders and, in agreement with in vitro accessibility data, the β-carotene concentration in the chylomicrons of these subjects was significantly higher in the group consuming the optimised soup, while no changes were found for lycopene. Postprandial chylomicrons from the optimised soup group exhibited significantly higher antioxidant activity in HepG2 cells than the other group. The stimulation of HepG2 cells by human postprandial chylomicrons seems useful for evaluating the antioxidant effect of different food matrices.     

热处理对不同颜色番茄中类胡萝卜素异构化和降解的影响

为综合利用彩色番茄资源,对比不同颜色番茄中类胡萝卜素的组成,研究类胡萝卜素热稳定性,阐述其异构化和降解的规律.利用高效液相色谱-二极管阵列检测器(HPLC-PDA)并配备YMC Carotenoid C30色谱柱分离类胡萝 卜素,并以光谱特征鉴定异构体,系统分析番茄中类胡萝卜素组成,并探究热处理温度和时间对其类胡萝卜素...     

Extraction and quantification of major carotenoids in processed foods and supplements by liquid chromatography

A simple, fast and robust method with minimum steps, small sample size and amounts of solvents was developed to determine major carotenoids contents in processed foods, tablets and gel capsules. The method involves dispersion of the sample in hot water (60 °C) with added butylated hydroxytoluene (BHT) in ethanol to minimize oxidation, followed by extraction with chloroform and analysis by liquid chromatography. Chromatographic parameters were: a C30 column protected with a C18 guard cartridge; gradient elution at the rate of 1.0 mL/min starting with 100% methanol (A) and ending with 40:60 (v/v) methanol/isopropanol (B); detection set at 450 nm for carotenoids, and 325 nm for retinol, retinyl acetate and retinol palmitate. The method exhibited: (i) high degree of repeatability (%rsd); (ii) linear calibration curves (r² ? 0.9998); (iii) low detection; and quantification limits. The method was validated with standard reference material 2383 for trans-β-carotene; and tested for α-, and β-carotenes, lutein, zeaxanthin, cryptoxanthin, trans-retinol in processed foods, tablets and gel supplements.     

热带水果中抗氧化物质的抑肿瘤和降血脂活性

热带水果中存在不少具有抑瘤和降血脂活性的抗氧化物质。本文综述了热带水果抗氧化物质的分离和生理活性研究的现状及其应用前景     

我国主要热带水果的干燥和贮藏保鲜技术研究进展

目前我国热带水果产业还处于小规模、低层次的加工状态。干燥和贮藏保鲜是保障我国热带水果产业健康、稳定发展的重要技术。本文针对我国主要热带水果(香蕉、菠萝、荔枝、龙眼和芒果)干燥和贮藏保鲜环节的相关技术进行综述,包括组合干燥工艺、热处理、溶剂处理以及气调贮藏或包装,旨在为其采后贮藏保鲜和初加工提供参考。     

番茄果实降异戊二烯类香气物质合成与代谢调控研究进展

番茄中的类胡萝卜素及其由类胡萝卜素降解产生的降异戊二烯类芳香物质是果实风味的重要组成部分。其中，降异戊二烯类香气物质阈值极低，是番茄果实花香、果香的主要贡献者。近年来，番茄果实类胡萝卜素合成途径已经形成较为清晰的通路，但对其降解产物降异戊二烯类香气物质的研究多在产物分析的层面。该研究综述了番茄中降异戊二烯类芳香物质的组成和生物合成途径，以及影响降异戊二烯积累的因素及转录调控因子，以期为番茄风味品质的提升提供参考。     

超声波提取- 液相荧光法测定水果中壬基酚聚氧乙烯醚及其降解产物

为建立超声波提取热带水果中环境激素壬基酚聚氧乙烯醚及降解产物壬基酚、液相荧光法测定残留量的方法,对超声提取的温度、时间、功率进行条件优化,提取液经净化浓缩后,用C18 色谱柱进行分离,液相色谱荧光法进行测定。结果表明：样品中壬基酚聚氧乙烯醚及壬基酚在0.5～50μg/mL 范围内线性良好,检出限分别为0.04mg/kg 和0.008mg/kg,方法回收率分别为92%～102% 和75%～92%。该方法快速灵敏、准确度高,符合残留检测的要求。     

LYC-B基因沉默对紫色番茄果实主要色素及挥发性物质的影响

利用病毒诱导的基因沉默（virus-induced gene silencing,VIGS）技术,抑制紫色番茄果实成熟过程中番茄红素β-环化酶（LYC-B）基因的表达,并分析番茄果实中主要色素及挥发性物质的种类与含量变化。结果表明：LYC-B基因沉默可提高紫色番茄果实中番茄红素的含量;顶空固相微萃取-气相色谱-质谱联用技术检测到6-甲基-5-庚烯-2-酮等类胡萝卜素相关的挥发性物质的含量增加,反-2-辛烯醛、己醇、反-2-庚烯醛、水杨酸甲酯和顺-3-己烯醇等主要挥发性物质的释放量增加。因此,LYC-B基因沉默可以增加番茄红素及部分主要挥发性物质的含量,影响番茄果实的营养品质和风味品质。     

四种热带水果中膳食纤维的结构表征及单糖组成和理化性质分析

以菠萝蜜、洋蒲桃、莽吉柿、番荔枝为原料,采用化学结合酶法对其膳食纤维进行制备,并利用扫描电镜、红外光谱和化学分析等方法对制备的上述膳食纤维的结构表征、单糖组成和理化性质进行研究.结果表明:番荔枝中膳食纤维的含量较高,达(74.31±0.07)g/100 g;纤维素、半纤维素、木质素在四种热带水果的膳食纤维中含量存在明显...     

水杨酸缺失型突变体NahG和野生型番茄果实抗冷性的比较

本实验以番茄水杨酸(salicylic acid,SA)缺失型突变体(NahG)和野生型(wild type,WT)的采后果实为试材,于4?℃下贮藏28 d后观察番茄果实冷害症状,同时测定冷藏期间果实的冷害指数,游离脯氨酸含量,磷脂酶C(phospholipase C,PLC)、磷脂酶D(phospholipase D...     

果蔬及其制品中真菌毒素的污染与检测研究进展

果蔬在生长、贮存、运输及加工等一系列过程中,极易受到各种病原菌的侵染而发生腐烂,腐烂果蔬不仅造成巨大的经济损失,而且导致果蔬积累大量的真菌毒素。真菌毒素可通过食物链的传递对人或动物的健康带来巨大威胁。本文就果蔬中常见真菌毒素的种类、产毒菌株、侵染途径、产毒条件、毒性作用、检测方法和限量标准等方面进行详细的总结,旨在为果蔬中真菌毒素的控制提供参考。     

Physiological and Genetic Properties of Tomato Fruits from 2 Cultivars Differing in Chilling Tolerance at Cold Storage

ABSTRACT:  Postharvest tomato fruits are cold-sensitive, and easy to develop chilling injury (CI) at cold storage. Information on physiological and genetic characteristics closely related to CI is necessary because it is significant to realize CI development regular and find sensitive indicators reflecting cultivar cold tolerance, which are the basics to prevent CI. In this study, we used 2 tomato cultivars (Lichun and Santiam) differing in cold tolerance to analyze ion leakage, malondialdehyde (MDA), proline, catalase (CAT), and peroxidase (POD) in postharvest fruits chilled at cold storage. Expression of cold-response gene LeCBF1 , a key regulator in cold-response, was also detected. Results showed that ion leakage, with a high correlation coefficient (0.9661) to CI index, exactly reflected injury development phase and degree; sharp increase of MDA and proline content appeared at and before the time of main development phase of CI (10 d); however, fluctuant CAT and POD activities could not sensitively reflect CI development, since their regular changes didn't appear until the main development phase ended. Thus, ion leakage, MDA, and proline content were effective indicators for CI analysis in postharvest tomato fruits. Although physiological analysis was effective in CI analysis, it was complex to be used in judging cold tolerance. Expression of LeCBF1 gene swiftly responded to low temperature within 1 h. In accordance with those physiological parameters, LeCBF 1 expression level was positively correlated with cold tolerance and showed a high correlation to CI index (−0.9176). These suggested that LeCBF1 analysis could be effectively used in fast testing the cold tolerance of tomato.     

11种品牌玉米油脂肪酸及异构体的主成分分析

对市售的11种品牌玉米油开展了脂肪酸(包括脂肪酸及其异构体)组成与含量的调查研究。采用气相色谱技术,结合主成分分析法,分析了不同品牌玉米油中脂肪酸的差异性和相关性。结果表明,11种品牌玉米油中共鉴定出19种脂肪酸,包括7种饱和脂肪酸,5种不饱和脂肪酸,6种反式脂肪酸(TFAs)和1种共轭亚油酸(t,t-CLAs),平均含量分别为14.18×10~(-2) g/g,80.32×10~(-2) g/g,1.47×10~(-2) g/g和0.23×10~(-2) g/g;其中,亚油酸(C18:2-9c12c)、油酸(C18:1-9c)和棕榈酸(C16:0)依次是玉米油中含量最多的3种脂肪酸;不同品牌玉米油中脂肪酸含量存在显著性差异(p0.05)。主成分分析揭示了不同品牌玉米油在脂肪酸含量上的相似性、差异性及脂肪酸之间相关程度,TFAs和CLAs正相关程度高。本研究为评价市售玉米油脂肪酸品质特征提供了较为全面的数据支撑。