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• Preliminary Study on Effects of The Technological Parameters to Polyphenols Extraction Yield from Tea Leaves (Camellia snensis(L) O. Kuntze)

  Giang Trung Khoa, Bui Quang Thuat, Ngo Xuan Manh

  Received: 02-03-2017 / Accepted: 27-04-2017

   Abstract PDF (VIETNAMESE)

  In this study, the technological parameters for extraction of polyphenols from tea have been examined. The results indicated that the suitable parameters of this process were determined as follows: water content of the material of 5%, material size of 0.5 - 1.0 mm, 50% (v/v) acetone solvent, ration of material/solvent of 1:12, extraction time of 2 h, extraction temperature of 450C and three times of extraction. In addition, with these parameters, the polyphenols extraction yield was 84.55%.

• Study on using Cellulase in the Processing of Beverage from Medical Mushrooms

  Nguyen Thi Bich Hang, Nguyen Doan Nhat Quynh, Ho Thi Trang, Doan Chi Cuong, Bui Duc Thang, Tran Dinh Chi

  Received: 18-08-2023 / Accepted: 12-04-2024

   Abstract PDF (VIETNAMESE)

  Cellulase was applied to improve the extraction efficiency from medicinal mushroom extracts of Ganoderma lucidumand Trametes versicolor. In addition, the study proposed the process of producing beverages from those medicinal mushrooms and chrysanthemum (Chrysanthemum indicum)flowers. The findings show that, for extracting from Yunzhi’s extract, using 3% cellulasefor 15 minutes attemperature of 70C gained the highest extraction efficiency. Meanwhile, the extraction efficiency from Lingzhi’s extract was highest with 4% cellulasein 25 minutes attemperature of 70C. Mushroom beverage with a mixture of 25% Lingzhi, 50% Yunzhi, 20% Chrysanthemum flowers, and 5% sweet grass (Stevia rebaudiana) had the highest sensory evaluation according to the TCVN3215-79. The processed product meets quality standards on food hygiene and safety according to QCVN 8-2/2011-BYT for permissible limits of heavy metals and Decision 46/2007/QD-BYT for biological and chemical contamination in food.

• Assessement of Land Management and Land Use of Economic Organizations Which Were Assigned or Leased Land by the Government in Me Linh District, Ha Noi City

  Do Thi Tam, Pham Minh Giap

  Received: 18-03-2015 / Accepted: 09-06-2015

   Abstract PDF (VIETNAMESE)

  The study aims to assess land management and land useof economicorganizationswhich were assigned or leased land by the governmentin Me Linh. Thus, propose solutionsto enhanceland use efficiency, at the same time to limit the cases of breaking the Land law. The research used intergrated analysis and comparisonmethods. The result shows thatthere were 217economicorganizationswhich wereassigned or leased land with a total area of ​​927.50 ha in Me Linh District. 25 organizations used the land for improper purposes with an area of 14.27 ha; 9organizations used land for leasing to another organization with an area of 13.20 ha; 5 organizations had land in dispute with an area of 13.10 ha; 16 organizations used land as a join capital in business with an area of 34.74 ha and 13 organizations with 84.55 ha of land which have not put in to use yet. To remedy thesesituations, it is necessary to promulgate appropriate policies and laws, economical solutions, scientific solutions and management solutions.

• Extraction and Color Stability Evaluation of Crocin from Gardenia Jasminoides Ellis

  Nguyen Thi Thanh Thuy, Nguyen Thi Hien

  Received: 29-08-2016 / Accepted: 20-12-2016

   Abstract PDF (VIETNAMESE)

  Crocin belongs to the carotenoids group and is found a lot in Gardenia jasminoides Ellis. It is not only capable of creating color for food, but also has a lot of pharmaceuticalologicaleffects such as improving memory, anti-convulsants, anti-depressants, anti-oxidation, anti-tumor, etc.…The Oobjectives of this study wereisto detemine the crocin extraction methodology from Gardenia jasminoides Ellis and the color durability stability in different conditions. Carotenoid content was determined as described by Kotikova et al., 2011. Crocin content was determined by the Ultraviolet-visible spectroscopy (UV - VIS) at 440 nm wavelength. The results indicated that Gardenia jasminoideswas is apotential material to provide theobtainlarge highcrocin at concentrations,up to 16.04mg/g,for fresh material and 14.63mg/g for driedymaterial. The crocin extraction efficiency reached the peak with ethanol: water solvent (40:60, 50:50, v/v). The best results foroptimalsolvent : raw materials ratioand;fresh and dry materials extracting conditions corresponding were20ml/1g at 40°C in 45 minutes; 25ml/g at 70°C in 60 minutes, respectively. Crocin is stable at the temperatures below 100°C withinduring140 minutes. Besides, crocin is also stable in weak acidand,neutral and alkaline conditions.

• Determination of Total Flavonoid, Anthocyanin Content and Antioxidant Activity of the Fractions Extract from Butterfly Pea (Clitoria Ternatea) Flowers

  Truong Van Xa, Tran Kim Thoa, Nguyen Thi Huynh Nhu

  Received: 03-08-2021 / Accepted: 01-03-2022

   Abstract PDF (VIETNAMESE)

  The extract from butterfly pea (Clitoria ternatea) flowers was done in ethanol 60% and methanol 50% and itsfractions were eluted byhexane: ethyl acetate with increasing polarity. Total efficiency of flower extraction in ethanol (17.01%) was higher thantotal extraction of the flowers in methanol (15.22%). Fraction 2 of the flowers extracted in methanol showed the highest total flavonoid content (621.43 ± 2.33mg QE/g extract). The highest total anthocyanin content in fraction 3 extracted in ethanol was 119.58 ± 1.19mgQE/g extract. The antioxidant activitiesof extract from butterfly pea flowers were investigated through its ability to reduce H2O2and free radical DPPH. The IC50value inhighfraction 3 of the extract in methanol was 166.29 ± 2.53 µg/ml and its ability to reduce H2O2was stronger than that of ascorbic acid at 176.23 ± 3.21 µg/ml. The IC50value in high fraction 2 and 3 of the flower extract in methanol was 589.27 ± 4.09 and 412.34 ± 2.91 µg/ml, respectively and all of these was able to deoxidize DPPH stronger than that of ascorbic acid at 656.23 ± 3.44 µg/ml. Thus, high fraction 3 with ethyl acetate eluent was suitable for the extraction of plant compounds from butterfly pea flowers with the strongest antioxidant activities. Furthermore, it is suggested that Clitoria ternateacan be used in dietary applications with a the potential to reduce oxidative stresses.

• Tea (Camellia sinensis O. Kuntze) Seed Oil - Physical Properties and Applicability in Food Industry: an Overview

  Phan Thi Phuong Thao, Nguyen Vinh Hoang, Le Minh Nguyet, Vu Hong Son

  Received: 01-03-2021 / Accepted: 04-05-2021

   Abstract PDF (VIETNAMESE)

  Tea (Camellia sinensisO. Kuntze) is one of the most popular crops and is considered a traditional beverage in many countries. The tea seed oil has been studied with the objectives to analyze the physical and chemical properties with a view for quality assessment, composition and applications. Physical and chemical properties such as state, specific gravity, acid value, peroxide value, iodine value, saponification value etc.were studied.Similar to olive oil, tea seed oil is a high-quality cooking oil with great stability because it has a large number of natural antioxidants including carotenoid (3.2 mg/kg), total polyphenols (8.68 mg/kg) and vitamin E (262.4 mg/kg). Moreover, tea seed oil is vegetable oil with high nutritional values due to its high content of unsaturated fatty acids (81.8 %), especially linoleic acid (22.3 %), which was previously proved to be useful in reducing cholesterol levels in the blood and preventing heart diseases, high blood pressure, and cancer. Studies show that different extraction methods of tea seed oil such as pressing, extracting by solvent, supercritical fluid, etc., yield oil with different efficiency and quality.

• Research Producing the Instant Powder Product by Extracting Solution from VietnamMulberry Leaves (Morus albaL.)

  Hoang Thi Le Hang

  Received: 29-05-2012 / Accepted: 20-08-2012

   Abstract PDF (VIETNAMESE)

  The instant mulberry powder was produced by spray drying from condensed liquid extraction of mulberry leaves (supplemented with some additives). In this experiment, we have used the drying spray method (dryer spray MOBILE MINOR - Denmark) to produce instant powder from mulberry leaves grown in Viet Nam. Based on research and survey of technology parameters affect the drying and the rate of blending of additives suitable for the purpose of producing instant powders that DNJ content ≥ 1%, with taste, attractive colors, easy to use, we have identified technological processes producing instant powder of mulberry leaves with the specifications as follows: Using extraction solutions with total sub solid 200Bx the input temperature is 1300C, the input flow pump is 1500ml / h, the efficiency of product reached 60% (Wsp <5% ). To create tasting of product, condensed solution of dry mulberry leaves should be added a number of additives such as 0.6% sweet grass; 6% strawberry flavor.