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41.
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Minerals and heavy metal concentrations of 23 plants (arial parts, leaves, bark, stem, root, rhizome, dried berries, seeds) possessing health-promoting effects and used in indigenous medicines (as medicinal food) were determined using inductively coupled plasma atomic spectrometry. Vital essential minerals and heavy metals were present in all the samples analyzed. The majority of the plant materials were rich in some of the essential minerals like Na, K, Ca, Fe, Mg, Cu, Mn, and Zn, which are known to be beneficial for health. The plant material of Vitiveria zizinalis had highest concentration of toxic heavy metals, including arsenic (53.1 mg/100 g), chromium (6.74 mg/100 g), cobalt (10.2 mg/100 g), mercury (3.6 mg/100 g), and nickel (3.28 mg/100 g). Results of the present study provide vital data on the availability of some essential minerals, which can be useful to provide dietary information for designing value-added foods and for food biofortification. Apart from this, data on the contaminant levels of heavy metals highlights the necessity on the quality and safety concerns about their use.  相似文献   
43.
The instant controlled pressure drop (DIC) process was used as a post-harvesting treatment, followed by hot air drying and shade polishing. DIC treatment, which is carried out at P = 0.4–0.6 MPa, has many advantages in terms of processing time (not exceeding 30 s) and drying kinetics (about 3 h instead of 1 day under standard 50 °C hot air flow conditions). Shade polishing gives high quality rice with a whole-grain yield of 68-70% rather than the usual 52-60%. A tasting evaluation was carried out by an international panel and the rice was found to be perfect after a cooking time of 6 min, with an overcooked time of 18 min as against 17 min and 20 min, respectively, for conventional products. The shaded shelf life of the final product is much longer than 18–24 months.  相似文献   
44.
L. N. Lai    A. A. Karim    M. H. Norziah    C. C. Seow 《Journal of food science》2004,69(4):FCT249-FCT25
ABSTRACT: Using a Rapid Visco Analyzer (RVA), it was revealed that 2 alkalizing agents (Na2CO3 and NaOH) had a far larger effect on pasting properties of nonwaxy starches (wheat, corn, rice) compared with their effect on waxy starches (waxy corn and waxy rice). It was hypothesized that the alkalizing agents have a greater propensity to attack the amorphous regions of the nonwaxy starch granules, thereby causing increased leaching of amylose molecules and possibly also some hydrolysis of starch chains. As a result, the RVA pasting profile of a nonwaxy starch, in the presence of alkali, was drastically altered to one that more closely resembled that of its waxy counterpart without added alkali.  相似文献   
45.
L. N. Lai    A. A. Karim    M. H. Norziah    C. C. Seow 《Journal of food science》2004,69(4):FCT287-FCT29
ABSTRACT: Using differential scanning calorimetry and pulsed nuclear magnetic resonance (NMR), it was found that the presence of Na2CO3 and NaOH retarded retrogradation of aged starch (wheat, corn, waxy corn, rice, and waxy rice) gels during storage at 4°C. At the same level of addition (based on a fixed starch/water ratio), the effect of NaOH was observed to be more pronounced than that of Na2CO3. Kinetic studies using pulsed NMR showed a progressive reduction in rate of starch retrogradation with increasing concentration of alkali (up to a level of 1 g/100 starch).  相似文献   
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47.
Abstract: The direct consumption of vegetable proteins in food products has been increasing over the years because of animal diseases, global shortage of animal protein, strong demand for wholesome and religious (halal) food, and economic reasons. The increasing importance of legume and oilseed proteins in the manufacturing of various functional food products is due to their high‐protein contents. However, the greatest obstacle to utilizing these legumes and oilseeds is the presence of antinutrients; but these antinutrients can be successfully removed or inactivated by employing certain processing methods. In contrast, the potential negative impact of the antinutrients is partially balanced by the fact that they may have a health‐promoting role. Legumes and oilseeds provide well‐balanced amino acid profiles when consumed with cereals. Soybean proteins, wheat gluten, cottonseed proteins, and other plant proteins have been used for texturization. Texturized vegetable proteins can extend meat products while providing an economical, functional, and high‐protein food ingredient or can be consumed directly as a meat analog. Meat analogs are successful because of their healthy image (cholesterol free), meat‐like texture, and low cost. Mycoprotein is fungal in origin and is used as a high‐protein, low‐fat, health‐promoting food ingredient. Mycoprotein has a good taste and texture. Texturized vegetable proteins and a number of mycoprotein products are accepted as halal foods. This article summarizes information regarding the molecular, nutritional, and functional properties of alternative protein sources to meat and presents current knowledge to encourage further research to optimize the beneficial effects of alternative protein sources.  相似文献   
48.
Fatty acids and essential oils from hydroponically cultivated Salvia officinalis leaves were analyzed by GC and GC–MS. Four different levels of NaCl (25, 50, 75 and 100 mM) were applied. The first results showed that salt treatment reduced significantly the plant growth by 61% and the total fatty acids (TFA) content by 32% at 100 mM NaCl. Alpha-linolenic, gadoleic, palmitic and oleic acids were the major fatty acids. Moreover, the polyunsaturated fatty acids decreased, while the monounsaturated ones increased with respect to increasing salinity. Regarding the essential oil composition, the main compounds were α-and β-thujone, 1,8-cineole, camphor, α-humulene, viridiflorol and manool at all salt treatments. The yield had a maximum increase at 75 mM NaCl. Hence, sage can be considered as moderately salt sensitive.  相似文献   
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50.
Synchrotron-based soft X-ray spectromicroscopy was used to probe nanometer-scale chemical heterogeneities of black carbon (BC) materials, including anthracite coal, coke, and activated carbon (AC), and to study their impact on the partitioning of one type of polychlorinated biphenyls (PCB-166: 2,3,4,4',5,6 hexachloro biphenyl) onto AC particles. Various carbon species (e.g., aromatic, ketonic/ phenolic, and carboxylic functional groups) were found in all of the BC materials examined, and impurities (e.g., carbonate and potassium ions in anthracite coal) were identified in nanometer-scale regions of these samples. We show that these chemical heterogeneities in AC particles influence their sorption of hydrophobic organic compounds (HOCs). PCB-166 was found to accumulate preferentially on AC particles with the highest content of aromatic functionalities. These new findings from X-ray spectromicroscopy have the following implications for the role of BC materials in the environment: (1) the functional groups of BC materials vary on a 25-nanometer scale, and so does the abundance of the HOCs; (2) molecular-level characterization of HOC sorption preferences on AC will lead to an improved understanding of AC sorption properties for the remediation of HOCs in soils and sediments.  相似文献   
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