Phenolic compounds,lycopene and antioxidant activity in commercial varieties of tomato (Lycopersicum esculentum)

Nine commercial varieties of tomato (Rambo, Senior, Ramillete, Liso, Pera, Canario, Durina, Daniella and Remate) produced in Spain were analysed for their lycopene content, content of phenolic compounds and antioxidant capacity. The phenolic compounds were characterised as flavonoids (quercetin, kaempferol and naringenin) and hydroxycinnamic acids (caffeic, chlorogenic, ferulic and p‐coumaric acids). Antioxidant activity was measured using the DPPH and ABTS assays. The concentrations of lycopene and the various phenolic compounds as well as the antioxidant activity were significantly influenced by the tomato variety. Quercetin, the most abundant flavonoid, was found in concentrations ranging between 7.19 and 43.59 mg kg^?1 fresh weight, while naringenin levels were lower than 12.55 mg kg^?1. The most abundant hydroxycinnamic acid was chlorogenic acid, with values ranging from 14 to 32 mg kg^?1 fresh weight, followed by caffeic acid, while p‐coumaric and ferulic acids showed similar concentrations lower than 5 mg kg^?1. The highest content of lycopene was found in Ramillete, Pera and Durina (>50 mg kg^?1 fresh weight), while the concentration in the other varieties was between 50 and 30 mg kg^?1, with the exception of Liso (less than 20 mg kg^?1). The antioxidant activity of tomato extracts varied with the tomato variety and the assay method used. Individual compounds found to be significantly related to antioxidant capacity were lycopene and ferulic and caffeic acids, but not quercetin and chlorogenic acid. © 2002 Society of Chemical Industry     

不同品种番茄对发酵番茄酱品质的影响

为了丰富番茄加工品种,开发一种发酵番茄酱。以四种新鲜的番茄品种为原料,添加凯里红酸汤来制作发酵型番茄酱并跟踪发酵过程中总酸、pH值、亚硝酸盐、番茄红素、可溶性固形物含量变化以及对成品感官评价。结果显示：美宝、奥宝番茄感官评价较好,品种间pH值变化无显著差异（P＞0.05）,美宝总酸含量、亚硝峰峰值最高,发酵结束后美宝总酸比市售番茄酱高出34%。美宝、经典欧卡番茄其与市售番茄酱番茄红素含量相近。美宝可溶性固形物含量最高为42%,各品种可溶性固形物含量均大于市售番茄酱。不同品种番茄酱发酵后成分具有一定的差异,结合不同品种的发酵番茄酱之间的特点,美宝番茄发酵后风味比市售番茄酱更佳。     

Comprehensive analysis of umami compounds by ion-pair liquid chromatography coupled to mass spectrometry

An ion-pair LC-ESI-MS method was developed capable of analyzing various reported umami or umami-enhancing compounds, including glutamic acid and 5'-ribonucleotides. The method was validated using tomato and potato samples and showed overall good analytical performance with respect to selectivity, detection limit, linearity, and repeatability. The method was applied to various tomato samples resulting in concentrations of glutamic acid and 5'-ribonucleotides that were in good comparison with literature. The methodology might also be used for the discovery of new umami (enhancing) compounds in an untargeted mode. This was to a certain extent demonstrated for tomato samples by correlating all peaks observed with the ion-pair liquid chromatography-mass spectrometry (LC-MS) method to sensory properties using multivariate statistics. PRACTICAL APPLICATION: This study describes the development and application of a LC-MS method, which can be used to quantify several known umami (enhancing) compounds in various foods. Furthermore, the method might be useful for the discovery of new umami (enhancing) compounds.     

Antioxidant properties of tomato juice as affected by heating

The changes in the overall antioxidant properties of tomato juice samples and model solutions as a consequence of heat treatments were studied. The antioxidant properties were evaluated both through the measurement of the chain breaking and the oxygen scavenging activities. While a decrease in the antioxidant potential was found for short heat treatments, a recovery of these properties was measured by prolonging heating times. Results suggested that the initial reduction in the overall antioxidant activity can be attributed not only to the thermal degradation of naturally occurring antioxidants but also to the formation of early Maillard reaction products (MRP) with pro‐oxidant properties. The gain in antioxidant activity coincided with the formation of brown MRP. © 1999 Society of Chemical Industry     

不同品种加工番茄挂枝期间果实品质的研究

以石河子主栽加工番茄品种为试材,对挂枝期间不同品种番茄果实/果肉的硬度、呼吸强度变化规律进行研究。结果表明:果实成熟后一定时期内,在没有病虫害的前提下,挂枝可以很好的保持垦番4号、垦番5、石番9号、石番36号、石番28号果实/果肉的硬度,减缓果实呼吸高峰的到来,但对其他品种果实品质保持作用不明显。总之,在遇到采收高峰期时垦番4号、垦番5号、石番9号、石番36号、石番28号可以适当晚采,但其他品种不可以延长采收期。      

不同品种番茄理化指标分析与研究

使用6种不同品种的番茄为实验原料,以可溶固形物含量、VC含量、番茄红素含量、色差为检测指标,分析各品种番茄中理化成分的含量,实验结果表明,里格尔87-5可溶固形物含量为5.3°Bx,其次为UC-82可溶固形物含量为5.1°Bx;不同品种间VC含量差异较大,其中UC-82中VC含量最高为28.9mg/100g;不同品种番茄番茄红素含量差异较大,其中里格尔87-5红素含量较高,可达到6.22mg/100g;在送样的6个品种番茄中,里格尔87-5的A值最大,色泽较好。     

Evaluation of antioxidative performance of tomato extracts obtained by different methods

BACKGROUND: Two extraction methods employing tetrahydrofuran and phosphate buffer (pH 7.4) respectively were used to process tomatoes. The antioxidant contents and antioxidative properties of extracts of four tomato cultivars were measured. To evaluate the overall antioxidative capacity of the tomato extracts, an antioxidative performance index (API) was used, defined as the average of four antioxidative assays, i.e. relative reducing power, ferrous ion‐chelating ability, 2,2‐diphenyl‐1‐picrylhydrazyl free radical‐scavenging activity and superoxide radical‐scavenging activity. RESULTS: A linear correlation between the total antioxidant content (TAC) and API of tomato extracts was found that was independent of the extraction method and tomato cultivar. CONCLUSION: The concept of representing multiple antioxidant activities by a single index is useful for evaluating the overall antioxidative capacity of antioxidants in tomatoes. Copyright © 2007 Society of Chemical Industry     

不同品种甘薯汁抗氧化活性的研究

研究了9个品种甘薯汁的酚类物质及其抗氧化活性,旨在为甘薯汁的开发利用提供参考依据。分别采用Folin-酚法、亚硝酸钠法、pH示差法测定了甘薯汁的总酚、总黄酮、总花色苷含量。结果表明,甘薯汁中含有丰富的酚类物质,不同品种甘薯汁的总酚、总黄酮和总花色苷含量存在差异。通过4个体外抗氧化体系（FRAP法、DPPH自由基法、ABTS+自由基法、OH自由基法）评价了甘薯汁的抗氧化能力。结果显示,不同品种甘薯汁所呈现的抗氧化能力不同,酚类物质含量较高的甘薯汁其抗氧化能力较强。从抗氧化能力方面考虑,杭引薯1号、杭引薯3号、浙紫薯1、13号这4个抗氧化能力较强的品种较适合用于果汁加工以及功能性饮品的开发。      

不同酿酒高粱酚类物质含量测定及抗氧化活性比较

以6种酿酒高粱籽粒为研究对象,分别比较其游离态与结合态总酚、总黄酮、酚酸物质种类及含量,并对其抗氧化活性进行 分析。 结果表明,不同酿酒高粱品种游离态总酚、总黄酮;结合态总酚、总黄酮含量分别在135.47～274.38 mgGAE/100 g、94.60～ 148.31 mg/100 g;618.27～1 383.17 mgGAE/100 g、123.06～434.84 mg/100 g。 酿酒高粱籽粒中游离态酚酸以阿魏酸、丁香酸与没食 子酸为主,平均含量分别为611.19 μg/g、380.66 μg/g、359.34 μg/g;结合态酚酸以阿魏酸、丁香酸为主,平均含量为1 608.33 μg/g、 376.78 μg/g。 酿酒高粱籽粒中游离态与结合态总酚ABTS抗氧化能力值分别占总ABTS能力值14.6%与85.4%;酿酒高粱籽粒中游离 态与结合态总酚FRAP抗氧化能力值占总FRAP能力值14.3%与85.7%。 酿酒高粱籽粒具有丰富的酚类物质,良好的抗氧化活性,且品 种间有显著性的差异（P＜0.05）。     

减压贮藏对番茄果实抗氧化物质和抗氧化酶的影响

为了研究不同减压处理对番茄果实后熟过程中抗氧化性的影响,以粉冠番茄为材料,研究了在43.6、73.0kPa和常压三个压力条件下,番茄中维生素C、番茄红素和谷胱甘肽含量,以及超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性变化规律。结果表明,减压贮藏显著推迟了番茄中维生素C含量的高峰,在一定程度上延迟了番茄红素和谷胱甘肽含量的高峰,并且压力越低效果越显著(p<0.05);在果实后熟过程中SOD、CAT活性逐渐下降,而减压处理可显著抑制SOD活性下降(p<0.05)。POD活性在贮藏期间呈现先降后升的趋势,减压处理可以有效地保持较高的抗氧化酶活性。结论:减压处理贮藏可以显著保护番茄果实中的抗氧化物质和抗氧化酶活性,而且一定范围内压力越低效果越好。      

Antioxidant properties and shelf‐life extension of fresh‐cut tomatoes stored at different temperatures

BACKGROUND: The feasibility of using modified atmosphere packaging (5 kPa O₂ + 5 kPa CO₂) to maintain the antioxidant properties of fresh‐cut tomatoes during shelf‐life was assessed through storage at different temperatures (5, 10, 15 and 20 °C). Health‐related compounds, antioxidant capacity, microbiological counts, physicochemical parameters and in‐package atmosphere of tomato slices were determined. RESULTS: Initial lycopene, vitamin C and phenolic contents and physicochemical parameters of tomato slices were well maintained for 14 days at 5 °C. Lycopene and total phenolic contents were enhanced over time in tomato slices stored at 15 and 20 °C. However, this increase in antioxidant compounds of fresh‐cut tomatoes during storage may be associated with excessive amounts of CO₂ (R² = 0.5679–0.7328) in the packages due to microbial growth. Although keeping tomato slices at temperatures above 10 °C increased their antioxidant content, the shelf‐life of the product was reduced by up 4 days. CONCLUSIONS: A storage temperature of 5 °C is appropriate for maintaining the microbiological shelf‐life of fresh‐cut tomatoes for up to 14 days and also allows the antioxidant properties of tomato slices to be retained over this period, thus reducing wounding stress and deteriorative changes. Copyright © 2008 Society of Chemical Industry     

Physicochemical and colorimetric evaluation of local varieties of tomato grown in SE Spain

The different physicochemical and colorimetric parameters which define fruit quality were evaluated in 12 varieties of tomato (Lycopersicon esculentum Mill) from several localities in SE Spain, using three widely grown commercial (F₁) hybrids as controls. Several local varieties were identified with better scores for specific quality parameters (fruit firmness, soluble solids content, pH, citric and malic acids and lycopene) than the commercially grown hybrids. These may find a place in the market as distinctive quality fruits or as source material for optimal quality characteristics in breeding programmes. The correlations obtained in the overall study of the results point to the advantages and disadvantages of choosing certain quality parameters. The colorimetric study showed that the ratio between the chromatic co‐ordinates of the CIELAB system (a*/b*) separated the fruits of the different varieties as a function of their external colour better than the tomato colour index (TCI). © 2001 Society of Chemical Industry     

Antioxidant phenolic compounds of pomegranate wines produced by different maceration methods

Various methods were evaluated in the production of ‘Hicaz’ pomegranate wine by microvinification. The chemical, phenolic and antioxidant characteristics of the wines were assessed by measurement of water‐soluble dry matter, acidity, density, alcohol content, volatile acidity, total monomeric anthocyanins, polarized colour intensity and individual phenolic compounds. Three different methods – classical maceration (N), seed‐supplemented maceration (S) and seed + enzyme supplemented maceration (E) – were applied. Total phenolic compounds of pomegranate must and wines (after 18 months of storage) were 1897 mg/L (must), 1663 mg/L (N), 1339 mg/L (E) and 1414 mg/L (S). Phenolic compounds in pomegranate must and wines included gallic acid, vanillic acid, caffeic acid, ferulic acid, p‐coumaric acid, hydroxycinnamic acid, epicatechin and catechin. Total antioxidant capacities (Trolox equivalents) of pomegranate must and wines (N, E and S) were 9.9 mm /L (must), 9.8 mm /L (N), 9.7 mm /L (E) and 9.5 mm /L (S). Copyright © 2017 The Institute of Brewing & Distilling     

Development of volatile compounds fingerprints by headspace-gas chromatography-ion mobility spectrometry in concentrated tomato paste and distillate during evaporation processing

Volatile profiles of fresh tomato pulp, concentrated pastes and distillates during evaporation were analysed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), and volatile fingerprints were established. Topographic plots showed ninety signal peaks, forty-two peaks (monomers and dimers) for twenty-five compounds were identified, including four alcohols, ten aldehydes, eight ketones, two esters and a furan. The fingerprints showed clear differences. After evaporation, phenylacetaldehyde, pentanal, 2-pentanone, 3-methylbutanal and benzaldehyde were newly detected in the concentrated pastes and distillates, while 2-heptanol, octanal, isopropyl acetate and 2-pentylfuran were no longer detectable. Prolonged evaporation caused volatile components in both pastes and distillates to decrease; most were evaporated into distillates, including all alcohols and esters, most aldehydes and some ketones. The fresh pulp, concentrated pastes and distillates were clearly distinguished by principal component analysis and hierarchical clustering analysis. This work provides a theoretical reference for tomato paste processing and the utilisation of distillate discarded.