Formation of hydroxymethylfurfural and furosine during the storage of jams and fruit-based infant foods

Simultaneous formation of hydroxymethylfurfural (HMF) and furosine (Fu) during the storage of three batches of jam samples (one commercial and two laboratory prepared) and one of fruit-based infant food (commercial), at 20 and 35 °C during 12 months, was investigated to evaluate the reliability of the combination of both parameters as quality indicators. In general, the concentration of both indicators increased with time and temperature of storage, formation of furosine being less temperature dependent than that of HMF. HMF was proved to be a good indicator of the severity of heating during manufacture and/or inadequate temperature during prolonged storage, whereas furosine may be a useful indicator of the storage conditions. The combination of both indicators can afford important information on the quality of jams and fruit-based infant foods during processing and storage.     

Indicators of non-enzymatic browning in the evaluation of heat damage of ingredient proteins used in manufactured infant formulas

Twelve infant formula ingredients of animal origin (caseinates, whey proteins and hydrolysates of casein and of whey proteins) and three of vegetable origin (soybean proteins) were analyzed. Furosine, hydroxymethylfurfural (HMF) and pyrraline were studied as indicators of thermal damage and available lysine as nutritional indicator, determined by HPLC in phase reverse and UV detector. The objectives were to evaluate heat damage to ingredients used in commercial infant formulas by measuring non-enzymatic browning indicators and to determine the nutritional value of these ingredients by available lysine determination. Very high furosine values were detected in whey proteins, ranging from 354 to 1,435 mg/100 g of protein. Lower furosine values were found in the remaining ingredients, ranging from 1.36 mg/100 g in hydrolyzed casein to 60.5 mg/100 g in sodium caseinate. Available lysine content ranged from 1.85 g/100 g of protein in hydrolyzed casein to 7.91 g/100 g in calcium caseinate. HMF was detected in whey protein samples between 0.16 and 2.47 mg/100 g of protein. Pyrraline was only detected in one sample of whey proteins at 41 mg/100 g of protein. Similar ingredients from different manufacturers show varied heat damage and nutritional values     

Adding value to hard date (Phoenix dactylifera L.): Compositional,functional and sensory characteristics of date jam

Second-grade dates (with a hard texture) from three potential Tunisian cultivars (Deglet Nour, Allig and Kentichi) showed the same sugar (∼73.30–89.55 g/100 g dry matter), fibre (∼7.95–18.83 g/100 g dry matter) and total phenolics (∼280.6–681.8 mg of GAE/100 g) content as dates of high quality. Deglet Nour and Kentichi varieties were characterised by a high content of sucrose and low reducing sugar content; contrary to Allig and the majority of other date varieties tested. This work intended to add value to these raw materials by using them in jam production. The corresponding jams were characterised in terms of chemical composition, physical (texture and water retention capacities) and sensory properties. Results showed a significant effect of the date variety on the composition and physical characteristics of date jams. Indeed, Allig jam was richer in reducing sugars and was characterised by its higher firmness and water retention capacity. To test the acceptability of these new products, we compared them with quince jam (the most consumed in Tunisia). Results showed that Allig and Kentichi jams presented a higher overall acceptability. However, quince and Deglet Nour jams did not show any significant differences (P > 0.05). Results from this work revealed essential information that could promote the commercialization of dzate jam.     

Combined use of HMF and furosine to assess fresh honey quality

BACKGROUND: The quality of honey can be affected by practices such as adulteration, inadequate storage or the application of severe heat treatments. Because hydroxymehylfurfural (HMF) is an indicator of honey freshness and furosine (ε‐2‐furoylmethyl lysine) has proved to be a useful chemical indicator of the progress of the Maillard reaction in foods, the aim of this work was to assess their usefulness as indicators of fresh honey quality. The effect of heat treatment, storage and adulteration with different types of syrups on HMF and furosine content has been studied. RESULTS: In fresh honey, HMF and furosine values ranged from 0.9 to 14.6 mg kg^?1 of product and from 3.06 to 12.06 g kg^?1 of protein, respectively. Heating of honey samples with different pH (3.76 and 5.14) produced slight increases in HMF content and negligible changes were detected in furosine values. The storage of fresh honey for 2 years caused a high increase in the HMF level, reaching values above EU limits. However, furosine showed a different behavior depending on the type of honey sample. Adulteration assays using different syrups produced an increase in HMF and a decrease of furosine values by dilution effect. HMF content of adulterated honey samples with syrup of known origin did not exceed EU limits. CONCLUSION: These results show the influence of long periods of storage or adulteration, using different percentages of corn or invert sugar syrups, on HMF and furosine content of fresh honey. This seems to indicate that the combination of HMF and furosine may be useful for evaluating the quality of fresh honey. Copyright © 2009 Society of Chemical Industry     

Quality and authenticity control of fruit purées,fruit preparations and jams—a review

Adulteration of foods is a serious economic problem concerning most food commodities, in particular fruit products. Since high-priced fruits command premium prices, producers of fruit-based products such as juices, jams, jellies, purées, and fruit preparations might be tempted to blend these products with cheaper fruits. In addition to admixtures of adulterants, the labelled fruit contents may not be met. Both types of adulteration are difficult to detect and lead to a deterioration of product quality. For consumer protection and to avoid unfair competition, it is of essential importance to guarantee both authenticity and compliance with the product specification. While approaches for the detection of fraudulent admixtures to fruit juices have extensively been reviewed, the objective of the present treatise is to provide an overview of the approaches so far suggested to detect and even quantify adulterations of the above-mentioned fruit products.     

EFFECT OF APPLE DECAY PROPORTION ON THE PATULIN, FUMARIC ACID, HMF AND OTHER APPLE JUICE PROPERTIES

Starking apples, classified by the decay proportion on the fruit surface as sound, 30, 60 or 100% decayed were used in the production of apple juice. Then patulin, fumaric acid, HMF, pH, brix and Hunter L, a and b values of apple juice samples were determined. Patulin and fumaric acid analysis were done with HPLC. The patulin concentration in juice samples produced with Starking apples that are sound, 30, 60 and 100% decayed ranged between 0.0–15.9 μg/kg, 47.1–500.3 μg/kg, 156.4–2257.5 μg/kg, 54.9–2508.6 μg/kg, respectively. The fumaric acid concentration in the same juice samples ranged between 0.00–0.20 mg/kg, 0.23–0.69 mg/kg, 0.41–2.08 mg/kg and 1.40–4.14 mg/kg. In general, the color values (L, a, b) of the samples produced from 100% decayed apples measured by reflectance with a Hunter colorimeter were low when compared with the others.     

天然野生山丁果果酒发酵工艺的研究

以野生山丁果为原料,葡萄酒活性干酵母为发酵菌种,研究山丁果果酒发酵工艺。考察果汁初始糖度、酵母接种量、发酵温度和果汁初始pH值等因素对山丁果果酒各项指标的影响,并在此基础上进行了优化试验,得到野生山丁果果酒发酵最佳工艺条件:糖度18%、初始pH值为4.0、发酵温度24℃、酵母接种量0.4%。该工艺发酵的野生山丁果果酒酒体呈浅粉红色,清亮透明,具有新鲜山丁果清新的果香和醇厚协调的酒香,酒度12.5%、残糖1.45g/L、VC 380mg/L、酸度4.8g/L。     

中国传统发酵豆制品γ-氨基丁酸研究

选择全国不同地区生产的61种传统发酵豆制品(包括豆豉、腐乳、豆酱和酱油),使用高效液相色谱法(HPLC)柱前衍生测定其γ-氨基丁酸(GABA)含量。研究表明,中国传统发酵豆制品富含GABA,从所试样品来看,腐乳样品GABA平均含量最高,为277.26mg/100g干重,含量最高的样品达1 159.46 mg/100g干重。所试豆豉、豆酱和酱油中平均GABA含量分别为116.81 mg/100g干重、68.81mg/100g干重和141.51mg/100mL。同一种类不同品牌发酵豆制品中GABA含量存在较大差异,这与发酵豆制品的不同生产工艺相关。通过工艺改进,可望富集GABA,生产富含GABA的功能性发酵豆制品。     

Determination of furan in jarred baby food purchased from the Spanish market by headspace gas chromatography-mass spectrometry (HS-GC-MS)

The aim of this paper is to offer a method based on headspace gas chromatography-mass (HS-GC-MS) spectrometry technique in-house validated and use to estimate furan concentrations in jarred baby-food samples purchased from the Spanish market. The validation was performed according to ISO 17025 and European Food Safety Authority (EFSA) requirements and the results obtained (limit of detection (LOD) = 0.05 µg kg^?1; limit of quantification (LOQ) = 4 µg kg^?1, lowest validated level; relative standard deviation (RSD) = 3.1–10.5%; recoveries = 85.4–101.5%) confirm that this method is fit for the routine analysis of furan in jarred baby food control. Furan was analysed in 39 different baby-food samples and the mean levels varied between 64.6 µg kg^?1 (rice and chicken samples) and less than or equal to the LOQ (fruit-based samples). The mean concentrations found for the different matrices were 5.0, 37.8, 25.2, 33.8 and 30.5 µg kg^?1 for fruit, vegetables, meat/vegetables, fish/vegetables and dairy-containing baby foods, respectively. According to the statistical analyses, fruit-based baby-food samples had significantly lower concentrations of furan. Mean values for the other matrices were at least five times higher, and this is in accordance with the levels reported in other studies.     

Occurrence of patulin and 5-hydroxymethylfurfural in apple sour,which is a traditional product of Kastamonu,Turkey

Apple sour is a traditional product of Kastamonu, Turkey. It is consumed by spreading on bread or drinking after diluting with water. The aim of this study was to determine patulin (PAT) and 5-hydroxymethylfurfural (HMF) in apple sour. This study is the first to evaluate the occurrence of PAT and HMF in apple sour. The samples were extracted with ethyl acetate using liquid-liquid extraction technique. PAT and HMF were determined by HPLC with UV detection. PAT was detected in all samples, and the PAT level in 94.9% of samples was found to be equal or greater than the legal limit for juice concentrates. The mean value for PAT was found to be 284 ± 307 μg kg^?1. PAT levels in 13 of 39 samples were in the range of 100 ≤ x < 200 μg kg^?1, two samples were in the range of 0 ≤ x < 50 μg kg ?1 and two samples were in the range of 1000 ≤ x < 1500 μg kg¹. HMF levels of all samples were above the legal limit for solid molasses. The mean value for HMF was found to be 16215 ± 13317 mg kg^?1. HMF levels of 10 of 39 samples were determined to be in the range of 10000 ≤ x < 20000 mg kg^?1, eight samples were in the range of 20000 ≤ x < 30000 mg kg^?1 and only three samples were in the range of 100 ≤ x < 1000 mg kg^?1. There was a significant and inverse relationship between HMF and pH of the samples. These results indicate that consumption of apple sour is a considerable risk in terms of HMF and PAT toxicity.     

Aroma,Sugar and Anthocyanin Profile of Fruit and Seed of Mahlab (Prunus mahaleb L.): Optimization of Bioactive Compounds Extraction by Simplex Lattice Mixture Design

In the present study, bioactive properties of black mahlab fruit and seed were investigated. Simplex lattice mixture design was used to determine the best solvent composition for the extraction of bioactive compounds of the samples. The content of total phenolics, total flavonoids, condensed tannins, total anthocyanins, and antiradical efficiency of mahlab fruit and seed extracts were investigated by spectrophotometric methods. Moreover, major sugar composition, individual anthocyanins, fatty acids, and aroma profile of the samples were determined by chromatographic methods. Effect of temperature on degradation of anthocyanins was also investigated, and degradation kinetic model parameters were calculated. Finally, the constructed simplex lattice mixture design model was optimized to estimate the optimum solvent mixtures that would yield maximum total phenolic content. The best solvent mixture was found to be 36 % of acetone and 64 % of water. It was concluded that the experimental and predicted values were in good agreement. Total phenolics and flavonoids of the fruit were 2,266 mg gallic acid equivalent/100 g of dry sample and 946.57 mg catechin equivalent/100 g of dry sample, respectively. Total anthocyanin content of the fruit was 505.7 mg/100 g of dry sample. Temperature showed a significant degradation effect on the anthocyanins.     

EFFECTS OF DIFFERENT PEKMEZ (FRUIT MOLASSES) TYPES ON CHEMICAL, NUTRITIONAL CONTENT AND STORAGE STABILITY OF CAKE

Pekmez is a natural sugar source that is obtained by concentration of fruit juice up to 70–80% soluble dry matter concentration. In this research, different kinds of pekmezes (mulberry, apricot, elecampane, grape and watermelon) were used in cake formulations instead of crystal sugar. Some chemical and nutritional properties and storage stability of cakes were investigated. Total and reducing sugar content of pekmezes ranged from 36.78 to 65.38% and from 33.54 to 64.70%, respectively. While water activity and crust color values of cakes generally decreased with pekmez addition, ash and mineral contents increased. Hydroxymethylfurfural content of cakes was found between 2.03 and 15.78 mg/kg and the highest value was obtained with grape pekmez addition. Ca, Fe, K, P and Zn contents of pekmez-added cakes were 92.72–177.82 mg, 4.09–22.70 mg, 4501.99–7208.45 mg, 255.68–416.41 mg and 2.91–4.86 mg/100 g, respectively. After 21 days of storage, apricot- and watermelon-added cakes were found to be softer than others cakes and control.

PRACTICAL APPLICATIONS

Preparation of cake with pekmez addition improved the nutritional value and especially apricot and watermelon addition gave increased shelf life. A new nutritious and delicious product was improved with pekmez additions. Elecampane and grape pekmez-added cakes were found as alternative food sources of Fe for anemic persons.     

Evaluation of acrylamide and selected parameters in some Turkish coffee brands from the Turkish market

The purpose of this study was to measure acrylamide (AA) levels and selected parameters of different traditional Turkish coffees. AA, 5-hydroxymethylfurfural (HMF), total reducing sugar, protein, pH, moisture, dry matter (DM) as well as ash, caffeine and soluble solids content (SSC) in DM, L*, a*, b* colour parameters of coffee samples were determined and the correlation between AA level and these parameters were investigated. A total of 36 coffee samples (20 Turkish, 8 Dibek and 8 Terebinth coffee) from the Turkish market were examined. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was validated for the detection and quantitation of AA in coffee samples. The calibration curve was linear (R² ≥ 0.999) over the range of 30–1000 μg kg^?1. The limit of detection (LOD) and limit of quantification (LOQ) were found as 4.6 μg kg^?1 and 15.5 μg kg^?1, respectively. The amounts of AA in analysed coffee samples were in the range 31.1 ± 0.6 to 323.4 ± 5.4 µg kg^?1. The highest mean AA levels were found in Terebinth coffees (240.3 μg kg^?1) followed by Turkish coffees (204.3 µg kg^?1) and then Dibek coffees (78.6 µg kg^?1). No tested Turkish coffee samples had an AA concentration above the indicative value (450 µg kg^?1) for roast coffee recommended by the European Commission (EC) in 2011. In addition, a strong positive correlation was found between HMF values and AA amounts of selected coffee types.     

枸杞果酒发酵工艺优化及营养功能成分分析

该研究以新鲜枸杞为原料制备果酒,并对枸杞果酒营养功能成分进行分析。以初始糖度、酵母接种量、发酵温度和初始pH值为自变量,以感官评分为响应值,通过单因素和响应面试验优化枸杞果酒发酵工艺条件。结果表明,枸杞果酒的最佳发酵工艺条件为初始糖度27 °Bx,酵母接种量0.20%,发酵温度22 ℃,初始pH值5.0。在此优化条件下,枸杞果酒酒精度为12.24%vol,感官评分为91.80分。枸杞果酒中的营养成分总糖、蛋白质、氨基酸的含量分别为（2.27±0.16） g/100 mL、（0.62±0.04） g/100 mL、（588.12±10.23） mg/100 mL;功能成分总多酚、总黄酮、多糖和甜菜碱的含量分别为（1.88±0.06） mg没食子酸当量（GAE）/mL、（1.63±0.03） mg 芦丁当量（RE）/mL、（7.17±0.01） mg/mL和（2.55±0.04） mg/mL。     

芒果胡萝卜复合果酒发酵工艺的研究

以芒果和胡萝卜为原料酿造复合果酒,并对其发酵工艺进行研究。采用单因素实验和响应面优化试验,分析原料比、SO₂添加量、初始糖度、初始pH、酵母添加量对复合果酒发酵的影响,并得到最优发酵条件。结果表明,最佳发酵条件为:芒果与胡萝卜原料比例为2:1(V/V)、SO₂添加量为55 mg/L、初始糖度为24%、初始pH为3.5、酵母接种量为0.12%。在此最优条件下,芒果胡萝卜复合果酒酒精度为13.62% vol、残糖4.6 g/L、总酸8.8 g/L、干浸出物23.0 g/L、甲醇98 mg/L。酒体色泽橙黄饱满、透明清亮,有浓郁的果香和酒香,口感甘甜醇厚。     

N-methyl carbamate pesticide residues in conventional and organic infant foods available on the Canadian retail market, 2001-03

Seven parent N-methyl carbamate insecticides, in addition to two transformation products of aldicarb (aldicarb sulfoxide and aldicarb sulfone), and a single transformation product of carbofuran (3-hydroxycarbofuran) were measured in infant and junior foods available on the Canadian retail market between 2001 and 2003. Carbaryl and methomyl were the only analytes present at levels above the limits of detection in juice, cereals, fruit, vegetables or meat samples analysed. Carbaryl was the most frequently (7.6%) detected compound and concentrations ranged from 0.6 to 18 ng g^-1. Detectable levels of carbaryl were most frequently found in foods prepared with fruit. Methomyl was detected (0.8 ng g^-1) in one chicken with broth sample analysed in the present study. In all cases, the concentrations observed were orders of magnitude below the maximum residue limits established for these compounds in the corresponding raw food commodities in Canada (100-10 000 ng g^-1). Dietary intakes of carbaryl and methomyl based on the consumption of infant foods tested ranged between 0.2-343 and 0.4-2.0 ng kg^-1 body weight day^-1, respectively.     

A COMPARISON OF FRUIT OF HIGHBUSH AND RABBITEYE BLUEBERRY CULTIVARS1

In 1986, 1988 and 1989, fruit from highbush blueberry (Vaccinium corymbosum L., cvs Collins, Bluecrop, and Herbert) and rabbiteye blueberry (V. ashei Reade, cvs Climax, Tifblue, and Menditoo) grown at the same location were compared for size, raw product quality, storage, and sensory attributes. Compared with rabbiteye blueberry fruit, fruit of highbush cvs were generally larger in size, volume, and surface area and higher in titratable acidity, higher Hunter color attributes of ‘L’, ‘a’, ‘b’, and chroma, protein, P, Ca, Mg, Mn, Fe, Cu, B (dry wt. basis), and higher in decay and water loss after 3 weeks storage at 7 C. Rabbiteye fruit, compared with highbush fruit, were generally higher in pulp pH, percent soluble solids, percent dry matter, seed weight per fruit, weight per seed, fruit height/width ratio, periderm dry weight per fruit, periderm wt. per surface area (in mg/cm²), sugar:acid ratio, firmness (as shear), and in sensory seediness. Fruit soluble solids, dry matter, hue, titratable acidity, pulp pH, and firmness of both species were influenced by weather (years).     

Copper content of commonly consumed food in Brazil

Little is known of copper content of Brazilian food. In this paper, copper contents of several typical Brazilian foods were determined. The samples were bought in retail stores in cities of the southeast region of Brazil. Atomic absorption spectrophotometry with wet oxidation of the organic material was employed. The highest copper content was found in beef liver (6.06 mg/100 g of fresh product). Lowest copper content was found in milk and in fish fillet, with values below 0.01 mg/100 g of fresh product. Crude beans, Nescau^TM and whole wheat had copper contents from 0.44 to 1.04 mg/100 g of fresh food. Other foods, such as fruits, vegetables, grain products, baked products, roots and meat products had copper contents varying from 0.02 to 0.41 mg/100 g.     

Nutrients in non-alcholic beverages in Nigeria

Forty-one samples of carbonated soft drinks in Nigeria have been shown, on analysis, to contain high sugar contents (mean value, 14·0%) despite the high cost of this ingredient; the Food and Drug regulations allow 9%–14%. There is a considerable divergence in the mean values of sugar for the four brands examined; 14·9%, 15·3%, 12·4% and 13·7% for the Cola, Fanta, clear drinks and fruit juice, respectively. Similar large deviations in mean values were recorded for other chemical constituents of the drinks. Ascorbic acid, for example, has an overall mean value of 12·2 mg/100 ml whereas individual samples have mean values ranging from 36·3 to 7·25 mg/100 ml. The ascorbic acid values for the fruit juice drinks fall short of expectation in all cases.     

Relationships between proteolytic and lipolytic activity and sensory properties (taste–odour) of traditional Turkish white cheese

Protein and lipid changes and their effects on the sensory properties (taste–odour) of Turkish white cheese were studied. Mean values for the chemical properties of white cheese were: total solids (TS) 44.39 g/100 g; titratable acidity 2.15% (as lactic acid); pH value 4.50; fat-in-dry matter 47.80 g/100 g; salt-in-dry matter 8.65 g/100 g; total nitrogen (TN) 2.50 g/100 g; water-soluble nitrogen (WSN) 0.48 g/100 g; ripening index (RI) 18.98%; tyrosine 65.00 mg/100 g; acid degree value (ADV) 385.96 mg KOH/100 g fat; volatile fatty acids (VFA) 15.54 mL 0.1 N NaOH/100 g and total free fatty acids (TFFA) 1325.96 mg/100 g cheese. Sensory scores for taste and odour were 23.67 (out of 35) and 8.28 (out of 10), respectively. The chemical qualities of the cheeses, including acidity, dry matter, fat-in-dry matter and VFA had an effect on flavour ( P  < 0.05).