Effects of refrigerated storage and processing technologies on the bioactive compounds and antioxidant capacities of ‘Marion’ and ‘Evergreen’ blackberries

The effects of refrigerated storage at 2 °C and 95% RH and processing treatments on the bioactive compounds and antioxidant capacities of ‘Marion’ and ‘Evergreen’ blackberries were investigated. During refrigerated storage, total phenolics (TPC), total monomeric anthocyanins (ACY), and radical scavenging activity (RSA) fluctuated in ‘Marion’, but TPC and ACY continuously declined in ‘Evergreen’. Oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) decreased by 20% and increased by 19% in ‘Evergreen’, respectively after 7-d refrigerated storage, while no changes (P > 0.05) in ‘Marion’ were observed. Compared with frozen samples, freeze-dried ‘Evergreen’ had higher TPC (21%), ACY (5.5%), and RSA (14%), while hot-air dried “Marion” had lower ACY (56%), ORAC (37%), and FRAP (27%) and hot-air dried ‘Evergreen’ had lower TPC (37%), ACY (84%), and RSA (13%). ORAC and FRAP in canned ‘Marion’ was 21-61% lower than that of frozen samples. Jam also had lower TPC and ACY (67-84%), RSA (˜80%), and ORAC and FRAP (65-77%) values than frozen ones in both varieties (P < 0.05). The 6-mo post-process room storage had little effect on the bioactive compounds of frozen and freeze dried samples, but reduced ACY in hot-air dried, canned, and jam samples, and antioxidant capacities of all samples (P < 0.05).     

光照处理对花生萌发过程中营养成分和活性成分的影响

以山东青花7号花生为原料,进行不同波长光照萌发实验。采用凯氏定氮法、液相色谱法等方法,对萌发花生营养和活性成分进行检测。结果表明,波长为380～450 nm、450～475 nm、495～570 nm、570～590 nm、620～750 nm、380～760 nm的紫光、蓝光、绿光、黄光、红光、日光及避光萌发48 h,花生中脂肪含量减少。蓝光、日光光照萌发48 h蛋白含量显著增加,其他波长光照蛋白含量无显著性差异。蓝光、绿光、黄光、红光、日光及避光萌发48 h还原糖含量为1.4%～2.33%,是原料的1.56～2.6倍。生育酚含量降低,红光光照萌发过程中多酚含量先下降后上升,萌发48 h含量达2.11 mg/g,为原料的1.17倍。白藜芦醇总量总体呈现上升趋势,紫光、红光光照萌发48 h,白藜芦醇总量分别为13.38 mg/kg、12.01 mg/kg,约为原料的3倍,γ-氨基丁酸含量均提高4倍以上。综合分析,不同波长光照处理可提高花生的营养和活性成分,该研究为优化花生萌发方法及研发萌发花生食品提供参考。     

热处理对乳中重要生物活性成分影响的研究进展

介绍了乳体系中存在的生物活性成分及其生理功能,阐述了牛乳中乳铁蛋白、乳过氧化物酶体系、免疫球蛋白、生长因子、溶菌酶等5种重要生物活性成分随热处理强度发生的变化,分析了不同生物活性成分的热稳定性及分子结构的变化,为乳制品功能性领域的研究与开发提供理论参考。     

Definition of the Mediterranean diet based on bioactive compounds

Antioxidant (polyphenols and carotenoids) and nonantioxidant (phytosterols) bioactive compounds and dietary fiber may have a significant role in health. The intake of these compounds is strongly linked with the high consumption of fruits, vegetables, and unrefined cereals. A whole-diet approach to these food constituents is intended to render the current definition of Mediterranean diet based on food consumption more comprehensive. The Mediterranean dietary pattern can be characterized by the following four essential dietary indicators: 1) Monounsaturated to saturated fatty acid ratio (range: 1.6 to 2.0); 2) Intake of dietary fiber (41 to 62 g/person/day); 3) Antioxidant capacity of the whole diet (3500 to 5300 trolox equivalent/person/day); 4) Phytosterols intake (370 to 555 mg/person/day). The contribution of foods and beverages to these parameters is described. Spanish National Food Consumption Data for the years 2000 and 1964 were used to quantify the lowest and highest range values. The occurrence of these indicators in the Mediterranean diet has specific characteristics and there is sufficient scientific evidence to support the beneficial health effects.     

Effects of pulsed thermosonication treatment on fungal growth and bioactive compounds of Berberis vulgaris juice

In this study, the single and combined effects of pulsed‐ultrasound amplitude (100 W, 30 kHz with 25 and 50% amplitude levels for up to 30 min) and temperature (65 °C and 75 °C) on fungal growth, total phenolics, flavonoids and antioxidant activity of Berberis vulgaris juice were investigated. The combination of pulsed ultrasound at 50% amplitude for 30 min at temperature of 75 °C as the most effective treatment was resulted in a reduction of about?3.083 ± 0.02, ?3.04 ± 0.03, ?3.10 ± 0.01 and ?2.88 ± 0.02 log (N/N₀) on S. cerevisiae, A. flavus, A. versicolor and B. fulva, respectively. Additionally, the highest total phenolics, flavonoids and antioxidant activity were noted for the barberry juice after 30 min of sonication with 50% pulsed‐ultrasound amplitude at either 65 °C or 75 °C. Pulsed thermosonication is a promising technology to extend the shelf life of B. vulgaris fruit juice because of the improvement of antioxidant activity as well as microbial quality.     

Effect of thermosonication on bioactive compounds in watermelon juice

Freshly squeezed watermelon juice was subjected to thermosonication treatments with processing variables of temperature (25-45 °C), amplitude level (24.1-60 ??m) and processing time (2-10 min) at a constant frequency of 20 kHz and pulse durations of 5 s on and 5 s off. Hunter color values (L*, a* and b*), lycopene (LC), phenolic content (TP) and ascorbic acid (AA) content were measured. Higher retention of AA and LC was observed at low treatment conditions. AA, LC & TP decreased significantly at higher amplitude levels and at the maximum processing time. A second order response function covering the range of experimental conditions investigated was obtained for each of the compounds measured. Model predictions for color parameters and bioactive compounds were closely correlated to the experimental results obtained. Prediction models were found to be significant (p < 0.05) with low standard errors and high coefficients of determination (R²). It was concluded that thermosonication significantly influences key watermelon juice quality parameters     

芽苗活性成分研究进展

对芽苗生长过程中含量逐渐增多的生物活性成分(如维生素、多酚、γ-氨基丁酸等)和抗氧化性等功能特性进行了综述,为改善人们的饮食结构和将其开发为可预防慢性疾病的功能性食品提供参考。     

鸡腿菇功能性成分及其功效研究进展

鸡腿菇营养丰富,味道鲜美,含有多种功能活性成分,是一种具有广阔开发前景的食用菌。概述了鸡腿菇多糖、活性蛋白、鸡腿菇素、酚类物质、甾醇等主要功能性成分及其相关生物学功能的最新研究进展,并对其今后的开发前景进行展望。     

Comparison of the levels of bioactive benzoxazinoids in different wheat and rye fractions and the transformation of these compounds in homemade foods

Benzoxazinoids are important phytochemicals found in wheat and rye that are associated with plant resistance against pathogens, and recent studies have emphasized the potential health-promoting role of these compounds i.e. anti-cancer, anti-allergy and anti-inflammation. Accordingly, an understanding of their distribution in seeds and the effect of different processing techniques on their transformation will be helpful in identifying the mechanisms of their production and distribution and will support the on-going efforts to utilize these compounds in health-promoting food products.     

Green tea preparation and its influence on the content of bioactive compounds

The effect of different extraction conditions and storage time of prepared infusions on the content of bioactive compounds of green teas and their antioxidant capacity were investigated. The content of total phenols, total flavonoids and total non-flavonoids in green teas was determined spectrophotometrically, while 7 flavan-3-ols, 6 phenolic acids and 3 methylxanthines were identified and quantified by using high performance liquid chromatography (HPLC–PDA). Among the tested green teas bagged green tea Twinings of London was recognized as the richest source of phenolic compounds (3585 mg/L GAE of total phenols). The most abundant phenolic constituents of green tea were flavan-3-ols, of which EGCG was prevailing in all teas (94.54–357.07 mg/L). The highest content of caffeine, as the most abundant methylxanthine, was determined in powdered green tea. The findings of this investigation suggest that extraction efficiency of studied bioactive compounds from green tea depends on the extraction conditions and that maximum extraction efficiency is achieved during aqueous extraction at 80 °C, for 5′ (powder), 15′ (bagged) and 30′ (loose leaf). In order to determine the antioxidant capacity of teas the DPPH, ABTS and FRAP assays were applied. Regardless of the extraction conditions all green teas exhibited significant antioxidant capacity in vitro, which was in correlation with their phenolic content, confirming that green tea is one of the best dietary sources of antioxidants.     

Laboratory performance on analysis of mandatory nutrients and preparation of nutrition labelling

This study assessed the performance of 17 laboratories in Thailand in analysing mandatory nutrients in salted, fried broad bean and in using data to prepare nutrition labels. Nutrient levels in the test material, as robust mean (x^∗) and robust standard deviation (s^∗), were assigned in line with ISO 13528. Data obtained from the laboratories were statistically evaluated against these values. Laboratories with satisfactory, questionable and unsatisfactory results for each nutrient were identified based on robust z-score. Laboratories achieving satisfactory analytical results (z-score ? 2) were for lipid, 82%; protein, 85%; Na, 82%; Ca, 62%; Fe, 81%; ash, 70%; and moisture, 62%. Reference values for some nutrients in broad bean powder were developed using data from satisfactorily performing laboratories. Less than 20% of the laboratories demonstrated good performance in preparing nutrition labels. Common mistakes were the nutrition information format, estimation of serving size and serving(s) per package.     

藜麦的营养物质及生物活性成分研究进展

综述了藜麦的营养成分以及功能性成分,以期为深入的研究和推广提供理论依据。     

Effects of sulphur nutrition during potato cultivation on the formation of acrylamide and aroma compounds during cooking

Lack of sulphur nutrition during potato cultivation has been shown to have profound effects on tuber composition, affecting in particular the concentrations of free asparagine, other amino acids and sugars. This is important because free asparagine and sugars react at high temperatures to form acrylamide, a suspect carcinogen. Free amino acids and sugars also form a variety of other compounds associated with colour and flavour. In this study the volatile aroma compounds formed in potato flour heated at 180 °C for 20 min were compared for three varieties of potato grown, with and without sulphur fertiliser. Approximately 50 compounds were quantified in the headspace extracts of the heated flour, of which over 40 were affected by sulphur fertilisation and/or variety. Many of the 41 compounds found at higher concentrations in the sulphur-deficient flour were Strecker aldehydes and compounds formed from their condensation, whereas only one compound, benzaldehyde, behaved in the same way as did acrylamide and was found at higher concentrations in the sulphur-sufficient flour. The reasons for these effects are discussed.     

Nutrients and bioactive compounds of Thai indigenous fruits

This study determined the nutritional potential of Thai indigenous fruits in terms of nutrients, bioactive compounds, and antioxidant activities. Three indigenous fruits were collected at two conservation areas in Kanchanaburi province, Thailand. The results showed that Phyllanthus emblica L. exhibited the highest levels of vitamin C (575 ± 452 mg/100 g), total phenolics (TP) (3703 ± 1244 mGAE/100 g), and antioxidant activities, as measured by DPPH, FRAP and ORAC assays. Compared to the other two fruits, Antidesma velutinosum Blume contained higher levels of most nutrients and dietary fibre (15.6 ± 5.9 g/100 g), as well as carotenoids (335 ± 98 μg/100 g) and phytosterols (22.1 ± 3.9 mg/100 g). Spondias pinnata (L.f.) Kurz was high in total phenolics (3178 ± 887 mGAE/100 g) and antioxidant activity. Moreover, high correlations were found between TP and antioxidant activities (r > 0.9). These Thai indigenous fruits are potentially good sources of nutrients, bioactive compounds, and antioxidant activities. Conservation and utilisation should be promoted for food security and consumption as part of a healthy diet.     

Effect of storage on the bioactive compounds and antioxidant activity of quince nectar

The changes of bioactive components and antioxidant activity of quince nectar were determined during 9 months of storage at 5, 20, 30 and 40 °C. The amount of total phenolics, flavonoids and antioxidant activity was significantly declined during storage at all temperatures. Loss of L‐ascorbic acid at 5, 20, 30 and 40 °C was 32.08%, 43.69%, 65.21% and 88.82%, respectively. L‐ascorbic acid degradation was in accordance with the first‐order reaction kinetics, and activation energy was found as 43.65 kJ mol^?1. After 9 months of storage, Hydroxymethylfurfural (HMF) contents of quince nectars were 15.01, 16.64, 21.69 and 57.89 mg kg^?1 at 5, 20, 30 and 40 °C, respectively. HMF accumulation fitted a zero‐order kinetic model, and activation energy was found as 88.30 kJ mol^?1. A significant correlation was found among L‐ascorbic acid, total phenolics, flavonoids and antioxidant activity.     

Germinated grains - Sources of bioactive compounds

Germination of seven selected commercially important grains was studied to establish its effects on the nutritional and chemical composition. The changes in the concentration of the nutrients, bioactive compounds and the inhibitory effect of extracts on α-glucosidase and α-amylase activities were investigated. These were measured through proximate analysis, inhibition assays and HPLC. Germinated sorghum and rye extracts inhibited (p<0.05) α-glucosidase activity, whereas barley and sorghum extracts exhibited higher inhibitory activities against α-amylase. Germinated grains contained substantial amounts of total phenolics with rye having significantly higher content compared with the non-germinated grains. Radical scavenging activities of the phenolic extracts were between 13% and 73% for non-germinated and 14% and 53% for germinated. Inositol phosphate (InsP) 4, 5 and 6 were noted in all the grains, but InsP 6 was significantly lower in concentration. This study indicates the potential of germinated barley, sorghum and rye for the development of effective physiologically bioactive compounds for the reduction of the risk of diabetic agents and colon cancer.