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Polyphenol Content (polyphenol + content)
Selected AbstractsEffect of fermentation on in vitro digestibilities and the level of antinutrients in moth bean [Vigna aconitifolia (Jacq.) Marechal]INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2008Amrit Bhandal Summary The effect of fermentation with varying temperatures and time periods on the nutritive value of Moth bean was studied. Results indicated that at 30 °C, protein digestibility increased from 60% in the non-processed moth bean to 77%, 78% and 80% and at 35 °C, increased to 81%, 83% and 85% following 12, 18 and 24 h of fermentation (controlled) period, respectively. Fermentation also caused an appreciable enhancement (96,133%) in starch digestibility with increase in period and temperature of fermentation. Fermentation of moth bean resulted in 24,34% reduction in phytic acid content at 30 °C and 33,42.5% at 35 °C. Polyphenol content was reduced by 42%, 48% and 51% at 30 °C and by 44%, 49% and 54% at 35 °C after 12, 18 and 24 h of fermentation period, respectively. Prolonging the period of fermentation from 12 to 18 and 24 h at 30 °C also caused a loss in TIA. [source] INVOLVEMENT OF PEROXIDASE AND POLYPHENOL OXIDASE IN MANGO SAP-INJURYJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2002K. SABY JOHN ABSTRACT Sap (latex) that oozes out from mango during harvest, upon contact with the fruit, causes dark spots (sap-injury) on the peel and reduces consumer acceptance and shelf-life of fruit. In this investigation different components responsible for sap-injury were identified. Mango saps from four Indian varieties were collected and separated into aqueous and nonaqueous phases. Whole sap, aqueous phase and nonaqueous phase were tested for their ability to cause sap-injury (browning) on mangoes. The nonaqueous phase caused maximum injury and the extent of injury caused by nonaqueous phases from different varieties was varied. Limonene, ocimene and ,-myrcene, the major terpenoids identified in saps of Indian varieties, caused injury. Similar type of injury on mangoes was also caused by organic solvents. Damage on Totapuri mango fruit was significantly lower compared to other varieties, whereas Totapuri nonaqueous phase caused injury on all other varieties. The peel of Totapuri variety had very low level of polyphenol oxidase, peroxidase and polyphenols compared to other varieties. Thus, a clear relation was found between the peel polyphenol oxidase, peroxidase activities, the polyphenol content in the peel and the extent of injury. Further, nonaqueous phase applied on peels previously heat-treated at 95C for 5 min, neither caused injury nor showed any enzyme activity. Thus, the results indicated that the terpenoid components of sap and polyphenol oxidase, peroxidase, polyphenols of peel are involved in sap-injury. [source] Retention and Distribution of Polyphenols after Pan-Frying of French Fries in Oils Enriched with Olive Leaf ExtractJOURNAL OF FOOD SCIENCE, Issue 8 2007A. Chiou ABSTRACT:,Palm oil, olive oil, and sunflower oil were supplemented with an extract rich in polyphenols obtained from olive tree (Olea europaea) leaves at levels of 120 and 240 mg total polyphenols per kilogram of oil. Pan-frying of potatoes was performed in both the enriched and the nonsupplemented oils under domestic frying conditions. Total polyphenol content was estimated by the Folin,Ciocalteau assay, oleuropein was determined by HPLC analysis, while other individual polyphenols by GC/MS analysis. Fourteen polyphenol species were identified in the olive leaf extract, among which oleuropein predominated (1.25 g/kg olive leaves). All the enriched oils contained oleuropein before and after frying. Oleuropein as well as other polyphenol species were detected in all French fries cooked in enriched oils. Polyphenol intake by consuming French fries pan-fried in the enriched oils was calculated to be 6 to 31 times higher than that in the case of French fries fried in commercial oils, being dependent on the frying oil type. [source] Antioxidative and antimutagenic activities and polyphenol content of pesticide-free and organically cultivated green vegetables using water-soluble chitosan as a soil modifier and leaf surface sprayJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2001Huifeng Ren Abstract Five green vegetables (qing-gen-cai, Chinese Cabbage, spinach, Welsh onion and green pepper) commonly used in our daily diet were analysed to determine their antioxidative and antimutagenic activities and chemical content of polyphenols. We obtained pesticide-free and organically cultivated (O) vegetables using water-soluble chitosan as a soil modifier and leaf surface spray (as an alternative natural insecticide) in order to investigate biofunctions induced or enhanced by such specialised cultivation practices. In addition, we purchased the same varieties of vegetables cultivated on an adjacent farm in the conventional manner (C) using pesticides and chemical fertilisers in order to examine the differences in biological activities and distribution of constituents responsible for such activities. The antioxidative activity shown by O vegetables was 120% times higher than that shown by C vegetables in the case of spinach and 20,50% higher in the case of Welsh onion, Chinese cabbage and qing-gen-cai. In comparison with C vegetables, the antimutagenic activity shown by O vegetables was higher against 4-nitroquinoline oxide (4NQO) in qing-gen-cai, Chinese cabbage and Welsh onion, against benzo[a]pyrene (BaP) in all five vegetables, against 2-amino-3-methylimidazo[4,5- f]quinoline (IQ) in qing-gen-cai, Chinese cabbage and green pepper and against 3-amino-1-methyl-5H -pyrido[4,3- b]indole acetate (Trp-P-2) in spinach only. Among all green vegetable juices tested for flavonoid composition, quercitrin, caffeic acid and baicalein in O vegetables were detected in concentrations 1.3,10.4 times higher than those found in C vegetables, suggesting the influence of different cultivation practices. © 2001 Society of Chemical Industry [source] An analytical survey of the polyphenols of seeds of varieties of grape (Vitis vinifera) cultivated in Greece: implications for exploitation as a source of value-added phytochemicalsPHYTOCHEMICAL ANALYSIS, Issue 1 2005Ramila Guendez Abstract Seed samples from 12 white and 25 red international and Hellenic native grape varieties (Vitis vinifera) were screened for their polyphenolic composition. The polyphenols determined were mainly of low molecular weight, including gallic acid, catechin, epicatechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate and the procyanidins B1 and B2. Average values of total content for white and red varieties (376 and 388 mg/100 g seeds, respectively) were very similar. Comparable results were observed with respect to the individual polyphenol content with seeds from red varieties being, in general, slightly richer. The predominant ,avanol monomer in white and red varieties was catechin (which accounted for 50.5 and 49.3%, respectively, of the total content), whilst gallic acid and epigallocatechin were the constituents showing the lowest content, respectively. The data obtained are discussed with regard to the exploitation of grape seeds as a low-cost source of value-added phytochemicals. Copyright © 2005 John Wiley & Sons, Ltd. [source] Effects of different maceration enzymes on yield, clarity and anthocyanin and other polyphenol contents in blackberry juiceINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 12 2009Wei-Dong Wang Summary Enzymatic maceration of blackberries was conducted with eight different pectinolytic enzyme preparations. Juice yields were increased greatly when macerated blackberries were treated with enzyme preparations (P < 0.05), but no significant difference in yield was found among different enzymes (P > 0.05). The amounts of anthocyanins and polyphenols in the juices as well as clarity of the juices were greatly varied because of different enzyme treatment. Juice prepared with Klerzyme 150 showed better clarity and greater amount of anthocyanins than the juices prepared with other enzyme preparations (P < 0.05). Studies on the uniform design for Klerzyme 150 enzyme revealed that the optimum conditions were 0.063% (v/w), 44 °C and 110 min for enzyme dosage, reaction temperature and reaction time, respectively. [source] Influence of rootstock and scion on antioxidant capacity of juice from new pomelo and mandarin varietiesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 11 2009Eran Raveh Abstract BACKGROUND: New pomelo and mandarin scion varieties growing under subtropical arid conditions were investigated for total antioxidants in the juice. Four different rootstocks,sour orange (Citrus aurantium (L.); SO), Volkamer lemon (C. volkameriana (Ten & Pasq.)), SB812 (C. sunki (Hort. ex Tan.) × Poncirus trifoliate (L.)) and C. macrophylla (Wester),were tested. RESULTS: Fruit juice was tested for total antioxidants, ascorbic acid and total polyphenol contents. Cyclic voltammetry (CV) analysis revealed three different antioxidant groups for pomelo and four groups for mandarin. CV analysis for the pomelo scion/rootstock combinations showed that ascorbic acid concentration was highest for scions grafted onto SO. Total polyphenol levels were similar among the pomelo varieties. Mandarin analysis revealed that ,Merav' scion/SO had the highest ascorbic acid concentration (1.91 ± 0.01 mmol L,1). Total polyphenol analysis discovered that ,Merav' 4/119-/SB812 gave the highest levels, while ,Ora Shani' scion grafted on to any tested rootstock contained the lowest CONCLUSION: We suggest that the SO rootstock is superior to Volka, 812 and macrophylla in terms of juice antioxidant capacity. For the pomelo, both ,Flamingo' scions were found to have high antioxidant production capacity, with ,Flamingo' 3/73 being slightly superior regardless of the rootstock. The best mandarins were ,Merav' hybrids in combination with SO rootstock. Copyright © 2009 Society of Chemical Industry [source] Storage stability of a high dietary fibre powder from orange by-productsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2009Juana Fernández-López Summary The goal of this investigation was to evaluate the effects of storage time and conditions on the physicochemical and microbiological properties of a high dietary fibre powder (HDFP). HDFP for this study was manufactured from orange juice industry by-products. The storage period was 11 months and samples were stored under vacuum or air exposure and under dark or light exposure. The HDFP is a stable product (based on chemical, microbiological and physicochemical properties) with large amounts of dietary fibre (71.62 ± 0.24 g 100 g,1 dry sample) and polyphenols content (40.67 ± 0.45 mg g,1 dry sample). Hesperidin is the major compound identified in HDFP (higher than 50% of total phenolic compounds). The packaging material used protects the HDFP only up to 6 months. After this time, the increase in moisture content decreases the quality of the product. The best storage conditions are packaging under vacuum and darkness. Both conditions preserve the colour of the fibres probably by means of avoiding pigment degradation. [source] | ||||||||||