Phenolic Compounds in Fresh and Dried Figs from Cilento (Italy), by Considering Breba Crop and Full Crop,in Comparison to Turkish and Greek Dried Figs

Fresh and dried figs are important components of the Mediterranean diet. In Cilento (Southern Italy), figs belonging to cultivar “Dottato” are used for the production of “PDO Cilento white figs,” as dried figs. In this article, we reported the characterization of the phenolic compounds in 19 fig samples: 9 fresh figs cultivar “Dottato” from Cilento (Italy), 10 dried fig samples from Cilento (2), Turkey (6), and Greece (2). The following phenolic compounds were identified and quantified by high‐performance liquid chromatography (HPLC)/UV‐DAD: chlorogenic acid, protocatechuic acid, vanillic acid, luteolin‐3,7‐di‐O‐glucoside, luteolin 7‐glucoside, apigenin‐7‐O‐rutinoside, rutin, quercetin‐3‐glucoside, and cyanidin‐3‐O‐rutinoside. A discriminative analysis between the peel and pulp of the samples was carried out. The 1st crop (“breba”) and the 2nd one (full crop) from Dottato figs were considered, as well as the effect of fig pollination. The majority of the phenolic compounds were predominant in the fig peel. Significant quantitative differences were found among fresh figs, whereas also some qualitative differences were obtained between fresh and dried figs from the same origin in Dottato cultivar, and among dried figs from different origins. Breba crop resulted richer in phenolics than figs of the 2nd crop. Considering the dried figs, the Turkish ones had the highest concentration in phenolic compounds. Other compounds such as the aminoacids tyrosine and tryptophan were also detected by HPLC‐DAD analysis in Dottato figs, probably due to the similarity of their chemical structure.     

Surveillance and control of aflatoxin contamination of dried figs and fig paste imported into the United Kingdom.

Samples of dried figs and fig pastes from Turkey supplied voluntarily by UK importers and retailers during the period November 1988 to January 1989 showed both a high incidence and high levels of contamination with aflatoxins. In the samples tested, 24% had total aflatoxin concentrations above 10 micrograms/kg, with the highest level being 165 micrograms/kg. More rigorous monitoring of the 1989 fig harvest was undertaken on bulk consignments for all figs from Turkey entering the UK. For whole dried figs 20 kg samples were taken (as 20 sub-samples), and for fig paste 5 kg samples were taken (again as 20 sub-samples). Figs were minced, blended with water and mixed prior to sub-sampling for analysis. Analysis was by immunoaffinity column clean-up with HPLC determination of aflatoxins with fluorescence detection. Examination showed that 11% of 112 consignments of fig paste and 9% of 93 consignments of whole dried figs were contaminated with total alfatoxin concentrations above 10 micrograms/kg, with the highest level of contamination being 40 micrograms/kg. As a result of this surveillance programme 14 consignments of figs were refused entry into the United Kingdom.     

Determination of aflatoxin B1 in dried figs by visual screening, thin-layer chromatography and ELISA

Aflatoxin B1-contaminated fruits were sorted out from 250 kg dried figs (five Turkish and three Greek batches) by bright-greenish-yellow fluorescence under UV light. The aflatoxins of the fluorescent figs were extracted by simple soaking in methanol. Aflatoxin B1 was determined by thin-layer chromatography. Parallel to this, an extraction for the determination of aflatoxin B1 was developed by a competitive ELISA and the two methods were compared with each other. In a highly contaminated batch of Turkish figs, statistically there was one fig among 350 which had a high aflatoxin content (greater than 100 ng/g fig) and one fig amongst 140 fruits with an aflatoxin B1 content of greater than 10 ng B1/g fig.     

Carry-Over of Aflatoxins to Fig Molasses from Contaminated Dried Figs

The carry-over of aflatoxins to fig molasses produced by using two different processing techniques from contaminated dried figs (> 1000 ppb of total aflatoxins) were examined by using a HPLC technique. The effects of extraction, bleaching and concentration steps on the reduction of aflatoxin levels were also investigated. The reductions in total aflatoxin levels in fig molasses produced by using the two techniques were detected to be 62 and 38%, respectively. Extraction, bleaching and concentration steps were observed to cause 22% reduction in total aflatoxin levels.     

Survey of aflatoxin contamination of dried figs grown in Turkey in 1986

A total of 284 dried fig samples, collected from fields during drying, and from warehouse and processing units in the Aegean region of Turkey in 1986, were examined for aflatoxin contamination. Aflatoxin B1, B2, and G1 were detected in 4, 2, and 2% of the samples, respectively, which were of the lower grade of figs taken from the drying stage. The average alfatoxin levels in positive samples were estimated to be 112.3 (B1), 50.6 (B2), and 61.4 ng/g (G1). The samples collected from storage (64 samples) and processing units (14 samples) contained no aflatoxins. The results of this survey show that aflatoxin contamination of Turkish dried figs in 1986 was highly correlated with the poorer grade of fig.     

THE AFLATOXIN CONTAMINATION OF FIG FRUITS IN AYDIN CITY (TURKEY)

The mold flora of 50 dried fig samples consumed in Turkey was examined and the aflatoxigenic ones were determined. Among 127 fungi isolated, 74 were Aspergillus, 24 were Trichoderma, 16 were Fusarium and 13 were Acremonium. Of the isolates, 17 were aflatoxigenic and four of them were capable to produce aflatoxin, three of which were characterized as A. flavus and one as A. parasiticus. Aflatoxin production of four strains was confirmed by high pressure liquid chromotography. The effect of UV irradiation on mold count and aflatoxin quantity was also tested. It was found that UV irradiation led to a decrease in the mold count and aflatoxin quantity.

PRACTICAL APPLICATIONS

Studies have shown that the concentration of aflatoxins may exceed the determined limits in dried figs. Its presence can be a potential threat to the health of consumers. Dried figs are one of the major agricultural export products of Turkey ( Senyuva et al. 2005 ). The effects of UV irradiation on mold flora of dried figs and aflatoxins have been examined. The Aspergillus flavus and parasiticus agar (AFPA) medium is used for detection of aflatoxigenic species, and coconut agar medium (CAM) is used to detect the aflatoxin-producing ability of aflatoxigenic strains. It was found that the reproduction of the molds in dried figs, consequently the aflatoxigenic mold strains, can be depressed by UV irradiation. It was found that increasing time of UV irradiation led to a decrease in the mold count in dried figs. In addition, a UV irradiation applied for 90 min, was found to decrease the aflatoxin quantity in dried figs in an amount of 25%. Because of inexpensiveness and easiness of the application it was concluded that the UV irradiation can be used as a practical application.     

Mycoflora and natural occurrence of aflatoxin, cyclopiazonic acid, fumonisin and ochratoxin A in dried figs

Mycoflora, the mycotoxigenic properties of moulds, and natural contamination with mycotoxins such as aflatoxins (AFs), cyclopiazonic acid (CPA), fumonisin B(1) (FB(1)) and ochratoxin A (OTA) were investigated in dried figs. Dry fig samples were collected from orchards during the drying stage in the Aegean Region of Turkey. Fungal isolates were identified using morphological, chemical as well as molecular methods. Mycotoxigenic characteristics of moulds were assessed by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Mycotoxins except CPA (by TLC) were determined by HPLC. All the fig samples were contaminated with moulds and 94.7% contained one or more mycotoxigenic species. The most prevalent moulds present in dried figs belong to the Aspergillus section Nigri members, being 93.9% positive for the samples, followed by Fusarium spp., Aspergillus section Flavi and Penicillium spp. On the other hand, Fusarium spp. had the highest count and the number of fumonisin producing Fusarium was also high. A total of 48% of 115 dried fig samples contained OTA (range = 0.1-15.3 ng g(-1)), 74.7% of the samples had FB(1) (range = 0.05-3.65 mg kg(-1)), 10.0% of the samples had aflatoxin (range = 0.1-763.2 ng g(-1)) and 24.3% of the samples were tentatively identified as being contaminated with CPA (range = 25-187 ng g(-1)). Dried fig samples were contaminated with one (33.0%), two (47.0%), three (5.2%) and four mycotoxins (3.5%). A total of 11.3% of dried fig samples were not contaminated with any of the four mycotoxins. To the best of our knowledge, CPA and fumonisin have been found for the first time in dried figs.     

Investigating the in vitro bioaccessibility of polyphenols in fresh and sun‐dried figs (Ficus carica L.)

In this study, in order to evaluate the in vitro bioaccessibility of fresh and sun‐dried figs, total antioxidant capacity (TAC), total proanthocyanidin content (TPA) and the major phenolic compounds were determined at different phases of simulated gastrointestinal (GI) tract digestion for Sarilop and Bursa siyahi fig varieties. Four major phenolic compounds (chlorogenic acid, rutin, cyanidin‐3‐glucoside (C3G) and cyanidin‐3‐rutinoside (C3R)) were investigated for GI tract digestion. The results of in vitro GI tract digestion revealed that the dialysed fraction (IN) represented 9–26% and 1–22% of the initial TAC of the whole‐fresh yellow and purple figs, respectively. Moreover, in case of 2,2‐azinobis(3‐ethylbenzothiazoline)‐6‐sulphonic acid (ABTS), TPA and chlorogenic acid contents, drying caused an increase in the IN fraction of yellow figs (38, 140, 50%, respectively). The bioaccessibility of C3G and C3R were quite low for fresh figs (0–5% of the initial values), whereas for dried figs, anthocyanins were not detected at all in the IN fraction.     

脐橙总糖近红外光谱模型传递研究

为实现近红外光谱模型在同类光谱仪器间的共享,以脐橙总糖为例,在主仪器上建立最优的偏最小二乘(PLS)近红外光谱模型,采用斜率截距(Slope/Bias)校正法和直接校正(DS)算法把主仪器上建立的模型传递到从仪器上,并探讨标准化样品个数对模型传递效果的影响。研究表明：在主仪器建立的模型经DS算法传递后,从仪器预测集的预测标准差(RMSEP)为0.448%,经Slope/Bias校正法传递后的预测标准差(RMSEP)为0.756%,DS算法更优于Slope/Bias校正法,利用直接校正法实现脐橙总糖傅里叶近红外光谱模型传递是可行的。     

Sensory Profiles for Dried Fig (Ficus carica L.) Cultivars Commercially Grown and Processed in California

A trained sensory panel evaluated the 6 fig cultivars currently sold in the California dried fig market. The main flavor and aroma attributes determined by the sensory panel were “caramel,” “honey,” “raisin,” and “fig,” with additional aroma attributes: “common date,” “dried plum,” and “molasses.” Sensory differences were observed between dried fig cultivars. All figs were processed by 2 commercial handlers. Processing included potassium sorbate as a preservative and SO₂ application as an antibrowning agent for white cultivars. As a consequence of SO₂ use during processing, high sulfite residues affected the sensory profiles of the white dried fig cultivars. Significant differences between dried fig cultivars and sources demonstrate perceived differences between processing and storage methods. The panel‐determined sensory lexicon can help with California fig marketing.     

Mycoflora and natural occurrence of aflatoxin,cyclopiazonic acid,fumonisin and ochratoxin A in dried figs

Mycoflora, the mycotoxigenic properties of moulds, and natural contamination with mycotoxins such as aflatoxins (AFs), cyclopiazonic acid (CPA), fumonisin B₁ (FB₁) and ochratoxin A (OTA) were investigated in dried figs. Dry fig samples were collected from orchards during the drying stage in the Aegean Region of Turkey. Fungal isolates were identified using morphological, chemical as well as molecular methods. Mycotoxigenic characteristics of moulds were assessed by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). Mycotoxins except CPA (by TLC) were determined by HPLC. All the fig samples were contaminated with moulds and 94.7% contained one or more mycotoxigenic species. The most prevalent moulds present in dried figs belong to the Aspergillus section Nigri members, being 93.9% positive for the samples, followed by Fusarium spp., Aspergillus section Flavi and Penicillium spp. On the other hand, Fusarium spp. had the highest count and the number of fumonisin producing Fusarium was also high. A total of 48% of 115 dried fig samples contained OTA (range?=?0.1–15.3?ng?g^?1), 74.7% of the samples had FB₁ (range?=?0.05–3.65?mg?kg^?1), 10.0% of the samples had aflatoxin (range?=?0.1–763.2?ng?g^?1) and 24.3% of the samples were tentatively identified as being contaminated with CPA (range?=?25–187?ng?g^?1). Dried fig samples were contaminated with one (33.0%), two (47.0%), three (5.2%) and four mycotoxins (3.5%). A total of 11.3% of dried fig samples were not contaminated with any of the four mycotoxins. To the best of our knowledge, CPA and fumonisin have been found for the first time in dried figs.     

Estimating sensory properties of common beans (Phaseolus vulgaris L.) by near infrared spectroscopy

Near infrared spectroscopy (NIRS) has been widely used to determine food chemical composition and to a lesser extent to evaluate sensory properties. Because sample preparation is relatively simple, NIRS is especially useful in situations where many samples must be analysed, such as gene-bank characterization or breeding. We aimed to assess the feasibility of using NIRS to predict aroma, flavour, mealiness, seed-coat perception, seed-coat brightness, and seed-coat roughness in common beans. Spectra of raw, undried cooked and dried cooked common bean seeds of 55 accessions were registered. Partial least squares (PLS) regression equations were developed between spectra absorbance and sensory properties scored by eleven trained panellists. Spectra registered on dried cooked samples generally yielded the best predictions. The relative ability of prediction (RAP) values were greater than 0.8 for flavour and mealiness and between 0.5 and 0.7 for seed-coat roughness and brightness. However, a suitable model to estimate the seed-coat perception was not found. These results make it possible to screen for samples that are close to the target sensory properties and thus substantially reduce the number of panel sessions needed for gene-bank evaluation or breeding.     

Aflatoxins, patulin and ergosterol contents of dried figs in Turkey.

Dried figs of three different categories, palatable, fluorescent, and cull, were investigated for their contents of aflatoxins (B(1), B(2), G(1) and G(2)), patulin, and ergosterol. Samples were obtained from four fig processing plants located in a major fig producing area in the Aegean Region in Turkey. Affinity column clean-up methods were employed for aflatoxins. All aflatoxins, patulin, and ergosterol were determined using high performance liquid chromatography. Palatable figs contaminated with trace amounts of aflatoxins, patulin, and ergosterol, so they posed no risk for the consumer when national and/or international regulatory limits were considered. Fluorescent figs were contaminated with high (117.9-471.9 ppb) aflatoxin levels and cull figs with high patulin (39.3-151.6 ppb) and ergosterol (4.5-18 ppm) levels. The total aflatoxins content was significantly correlated with the patulin content (r(2) = 0.813, p < 0.002) and the ergosterol content (r(2) = 0.920, p < 0.002) only in fluorescent figs. However there was no significant correlation between patulin and ergosterol contents of fluorescent figs. Furthermore, there were no significant correlations between the contents of any two of the three substances in cull figs. This is the first report on the presence of patulin and its co-occurrence with aflatoxin in dried figs.     

The use of high-performance liquid chromatography to detect ochratoxin A in dried figs from the Spanish market

BACKGROUND: Detection and quantification of ochratoxin A (OTA) in dried fig samples purchased in Spain has been carried out using high‐performance liquid chromatography with fluorescence detection after extraction with methanol and sodium bicarbonate, and clean‐up by using an immunoaffinity column. RESULTS: The detection limit of the method was 0.06 ng g^?1, and the limit of quantification 0.18 ng g^?1. OTA was detected in 31 (88.6%) out of 35 samples of dried figs analysed, with concentrations that ranged from < 0.1 to 277 ng g^?1. However, only three samples contained OTA concentrations above the tolerable level set by European Commission regulations for dried vine fruits (10 ng g^?1). CONCLUSION: The results of this survey show the value of monitoring OTA in dried figs especially if they are home grown. Copyright © 2011 Society of Chemical Industry     

拉曼光谱法快速检测猪肉脯中的掺伪鸡肉

目的 建立拉曼光谱法快速、准确、无损地检测猪肉脯样品中掺假鸡肉的方法。方法 制备33份猪肉中掺入不同比例鸡肉的肉脯样品,采集拉曼光谱数据,分别采用标准正态变换、多元散射校正、卷积平滑、归一化、一阶导数等5种不同预处理方法,对原始光谱数据进行预处理,采用连续投影算法、竞争性自适应重加权算法及随机蛙跳算法对光谱数据进行特征波长筛选,建立偏最小二乘法(partial least squares,PLS)模型对猪肉脯进行定性定量判别。结果 拉曼光谱数据经过多元散射校正处理的效果最佳,竞争性自适应重加权算法竞筛选效果更佳,构建猪肉脯中猪肉含量的PLS定量模型,其预测集决定系数和预测均方根误差分别为0.9762、7.2998。建立的PLS判别模型的校正集和预测集总判别正确率分别为100.00%和98.33%。结论 拉曼光谱分析技术可有效用于定性鉴别猪肉脯是否掺伪及定量分析猪肉肉脯中掺入鸡肉的比例,为肉脯掺假的快速无破坏性检测的应用提供支持。     

基于特征波长提取的哈密大枣可溶性固形物的高光谱预测

本文利用高光谱图像技术对干制后的哈密大枣可溶性固形物含量(SSC)进行预测研究。使用多种预处理方法对原始光谱进行处理,并对原始光谱和预处理后的光谱分别建立PLS模型,对比分析得出均值中心化(MC)处理效果最佳。对MC处理后的光谱经联合区间偏最小二乘算法(si-PLS)筛选后,再结合遗传算法(GA)和竞争性自适应重加权算法(CARS)提取哈密大枣SSC的特征波长,将提取的波长变量建立哈密大枣SSC的PLS预测模型。结果显示:利用MC-CARS-GA-si-PLS方法提取的16个关键波长变量(仅占全光谱变量的2%)所建立的PLS模型性能优于全光谱PLS模型。该模型的预测集相关系数(Rp)、预测均方根误差(RMSEP)和预测(RPD)分别为0.93、0.48和2.721。该方法提取的波长变量所建立的预测模型,不仅使模型简化,而且增强了模型的预测能力,为高光谱图像技术对水果及其干制品的定量分析研究提供了参考。     

Changes in pigment profile and surface colour of fig (Ficus carica L.) during drying

In this study, anthocyanins in three fresh fig varieties (Ficus carica L.) cultivated in Turkey were characterised and quantified by HPLC/DAD and HPLC/MS. In addition, the carotenoid composition of Sar?lop and Sar?zeybek, yellow fig varieties, was determined, and then the ripening‐ and drying‐related changes in carotenoids and surface colour of figs were monitored during conventional sun‐drying. Four different anthocyanins, cyanidin‐3‐glucoside, cyanidin‐3,5‐diglucoside, cyanidin‐3‐rutinoside (major anthocyanin) and pelargonidin‐3‐glucoside, were identified in samples. Lutein, zeaxanthin, β‐cryptoxanthin and β‐carotene were carotenoids in yellow fig varieties. Approximately 80% of carotenoid compounds in yellow fig varieties degraded at the end of drying (i.e. seventh day). L (lightness), a (redness and greenness) and b (yellowness and blueness) colour parameters were measured by Hunter Lab system. Great changes in carotenoid composition and surface colour were observed at ripening stage on tree. A significant reduction in L and b values that refers to browning in figs was made in the first 3 days of drying process.     

COMBINED EFFECT OF pH AND HEAT TREATMENT ON DEGRADATION OF AFLATOXINS IN DRIED FIGS

Dried figs are sensitive commodities to aflatoxin contamination. Although preventive methods are the logical solution to aflatoxin problems, once the product is contaminated, decontamination procedures are inevitable. In this study, the effectiveness of a procedure consisted of acidification/alkalization, and heat treatment in degradation of aflatoxins was evaluated. The pH of dried fig extracts was adjusted to 3.1, 3.5, 6, 8 or 10 by adding acid or base. Extracts were heated at 50, 75 or 98C for 1 or 2 h, and then the residual aflatoxin B₁, B₂, G₁ and G₂ were determined. The highest level of degradation for aflatoxin B₁ (97  ±  1%) and B₂ (87  ±  1%) were observed at pH 10 in samples heated at 98 and 50C, respectively. Some treatments resulted in 100% degradation of aflatoxin G₁ and G₂ so that they could not be detected.

PRACTICAL APPLICATIONS

Aflatoxin contamination is a serious problem for a number of processed and non-processed foods, including dried figs. This not only presents severe risks to human and animal health but also causes economic problems for countries such as Turkey, U.S.A., Greece and Spain, which produce and export dried figs. It is clear that detoxifying studies are unavoidable when the amount of crop contaminated by toxins is considered. Therefore, the food industry is in search of applications that are effective in mycotoxin detoxification and adaptable to food processes. This is the first report on degradation of aflatoxins in naturally contaminated dried figs by such a promising method.     

A New Approach to Predict Acidity of Bayberry Juice by Using Vis/Near Infrared Spectroscopy

A total of 76 bayberry juices were collected and their spectra features were got by using a vis/NIR spectroscopy. One mixed algorithm was used to predict the acidity (pH) of bayberry juice with partial least squares (PLS) and artificial neural network (ANN). PLS was used to find some sensitive spectra actives to acidity in juice, before doing this, the influence of various spectral pretreatments (standard normal variate, multiplicative scatter correction, S.Golay first derivative, wavelet package transform) were compared. The PLS approach with WPT preprocessing spectra was found to provide the best results, and the spectral reflectivity corresponding to them were regarded as the input neurons of ANN. Remnant values by subtracting standard values and validation values, were regarded as the output neurons of ANN. The calibration equation developed from them was used to predict the constituent values for the independent spectra of 30 samples. The results indicated that the observed results using PLS-ANN (r_p = 0.943) were better than those obtained by PLS (r_p = 0.932). At the same time, the sensitive wavelengths corresponding to the acidity of bayberry juices or some element at a certain band were proposed on the basis of regression coefficients by PLS. It indicates that using vis/NIRS technique to fast and nondestructive detection the acidity of bayberry juices was feasible.