• Title/Summary/Keyword: reducing sugars

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Effects of Salting Methods on the Physicochemical Properties of Kakdugi Fermentation (깍두기의 절임방법이 발효숙성 중 이화학적 특성에 미치는 영향)

  • 장명숙;김나영
    • Korean journal of food and cookery science
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    • v.15 no.1
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    • pp.61-67
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    • 1999
  • The effects of salting methods on Kakdugi (cubed radish kimchi) fermentation were evaluated. Kakdugi was prepared with various salting methods, salt concentrations, and settling times, and fermented at 10$^{\circ}C$ for up to 52 days. Radish (Raphanus sativus L.) cubes (2 cm size) were salted by using the following methods salt concentration of about 1.5% which was known appropriate for the organoleptic quality of Kakdugi: 1) Treatment S-1: applying dry salt uniformly onto the radish cubes, with a salt concentration of about 1.5% (w/w) and cured for 1 hr, 2) Treatment S-5: applying dry salt uniformly onto the radish cubes, with a salt concentration of about 1.2% (w/w) and cured for 5 hr, 3) Treatment B-1: brining radish cubes in a 8.5% (w/v) salt solution for 1 hr, 4) Treatment B-5: brining radish cubes in a 4.0% (w/v) salt solution for 5 hr. As the fermentation continued, the initial high decrease in pH has been retarded in all the treatments, of which the delaying extent was more significantly noted from B-1 and B-5 than S-1 and S-5. The pH of the Kakdugi which showed a good eating quality dropped to 4.3∼4.8 with the accumulation of total acids. Total vitamin C increased sharply at the palatable period of Kakdugi during the initial fermentation and then decreased gradually following a sigmoidal changing pattern. The reducing sugar levels were also influenced by salting methods and fermentation as sugars are converted into acids. High initial contents of reducing sugars and their subsequent rapid decrease were observed in “S” group than “B” group during fermentation. For nonvolatile organic acids, lactic acid increased consistently throughout the fermentation while malic acid, which was high at the initiation of fermentation, decreased rapidly afterwards at the palatable period of Kakdugi.

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Components in Chinese Cabbage (Brassica rapa ssp. campestris) as Affected by Soil pH: 6.9 vs. 7.6 (토양의 pH (6.9 vs. 7.6)에 의한 배추 (Brassica rapa ssp. campestris) 의 성분에 대한 영향)

  • Jo, Man-Hyun;Ham, In-Ki;Lee, Eun-Mo;Lee, Jo-Eun;Jiang, Nan;Lim, Yong-Pyo;An, Gil-Hwan
    • Korean Journal of Agricultural Science
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    • v.37 no.1
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    • pp.73-80
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    • 2010
  • Functional and nutritional components of 7 cultivars of Chinese cabbage (CC; Brassica rapa subspecies campestris) from China were analyzed to compare the effects of soil pH (6.9 vs. 7.6). The CC grew on the soil of pH6.9 (CC-6.9) contained significantly increased amounts (2.3~4-fold) of pectin, crude protein, vitamin C and vitamin E compared to the control. The contents of ash and minerals (Ca, Fe, Na, Zn, K and Mn) were also significantly increased in CC-6.9. However, CC-6.9 contained 16-75% lower contents of reducing sugars, cellulose and crude fat than CC-7.6. CC-7.6 contained more glucosinolates than CC-6.9; gluconasturtiin (20.68 vs. 0.84 $nmol{\cdot}g^{-1}$ wet wt) and gluconapin (202.55 vs. 0.15 $nmol{\cdot}g^{-1}$ wet wt). In conclusion, CC-6.9 had an improved texture (high pectin and low cellulose) and nutritional value (high in protein, Ca, Fe, Zn, vitamin C, and E), whereas CC-7.6 had better taste (high in reducing sugars) and anticancer functionality (high in glucosinolates).

Evaluation of Quality of Red Pepper with variations in Drying Methods (건조방법에 따른 건고추의 품질평가)

  • 김재열;금동혁
    • Food Science and Preservation
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    • v.3 no.2
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    • pp.137-143
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    • 1996
  • In order to produce the high-quality of dried red pepper with respect to a color and a taste we developed a automatic drier equipped with combined several heat energies(ADCHE). and compared the quality of ADCHE-treated red pepper with that of the pepper treated with conventional dryings such as natural, hot-air, and far-infrared ray dryings. The results obtained were as follows : (1) The contents of capsanthin varied significantly with drying methods within the range of 1.7 to 6. 4mg/g dry weight. The capsanthin level of red pepper treated with far-infrared ray drying was higher than that of the pepper treated with ADCHE showed the highest at 51.46mg/g dry weight of three drying methods. (2) As a result of determination of color intensity of-red-pepper using-a colorimeter, the red color intensity of the peppers was affected by drying methods irrespective of drying temperature, and especially a value of red pepper treated with ADCHE was appeared to be 19. 1, indicated that this pepper have the most bright color intensity. (3) The contents of soluble browing subatances increased with a increase in drying temperature, but L* value of red pepper treated with ADCHE was appeared to be 0.187, indicated that this red pepper have the most clear red color (4) The changes of capsanthin level of red pepper according to drying methodes did not show significantly, but generally a decreasing rate of capsanthin levels were lower in that order ADCHE

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Evaluation of Nutritional Characteristics of Platycodon grandiflorum Seeds (도라지 종자의 영양학적 특성 평가)

  • Kim, Yangji;Woo, Hyeryeon;Imm, Jee-Young;Kim, Seok Joong
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.2
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    • pp.478-484
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    • 2018
  • In this study, proximate composition, crude fiber, reducing sugar, free sugars, organic acids, minerals and amino acids of Platycodon grandiflorum seeds were analyzed to evaluate its nutritional value. Moisture, crude protein, crude fat, crude ash and carbohydrate contents of seeds were 6.97, 26.05, 27.46, 3.78 and 35.74%, respectively. Crude fiber of 6.31% and reducing sugars of 1.54% were also determined. Sucrose(1,661 mg/100 g) and lactic acid(1,224 mg/100 g) were most abundant free sugar and organic acid, respectively. Both phosphorus and potassium were main minerals that contained more than 700 mg in 100 g seeds. Amino acids analysis of 100 g seeds showed that glutamic acid(3.45 g), arginine(2.51 g), aspartic acid(1.66 g), leucine(1.29 g), lysine(1.10 g), alanine(1.05 g) and glycine(1.04 g) were abundantly contained in order, while others were less than 1 g.

Studies on the Utilization of Agricultural Wastes.(Part I) Acid-Hydrolysis of Straws and the Utilization of the Hydrolyzate (농산폐자원의 이용에 관한 연구(제일보) 산당화 및 당화액을 이용한 효모 생산)

  • Bae, Moo;Kim, Byung-Hong;Yoon, Ae-Sook
    • Microbiology and Biotechnology Letters
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    • v.1 no.1
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    • pp.31-36
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    • 1973
  • A method for acid-hydrolysis of agricultural wastes and its utilization was investigated. In order to obtain fermentable sugar solution from cellulosic wastes such as cereal straws and hulls, in particular, of rice, barley and wheat, the chemical compositions were analyzed and optimum conditions of hydrolysis determined. The cereal straws contain 42 to 55 % of crude cellulose including hemicellulose. On the hydrolysis with 1% of sulfuric acid at 40 psig, 35.6% of the reducing sugar based on the weight of dry matter was formed from rice straw, (variety Chinheung) in 30 min. More powerful condition of hydrolysis would appear to decompose the sugar formed into other compounds, for instance, furfural. Under atmospheric pressure with 5% of the acid, rice straw was hydrolyzed to 35% of reducing sugar content in 3 hours. Candida utilis could assimilate the sugars in the hydrolyzate up to more than 97%, and a yield of the yeast cells reached 55% to the utilized sugars.

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Chemical Changes During the Fermentation of Korean Soy-sauces and in Connection with its Fermentative Period (한국(韓國)간장의 당금중(中)의 화학적(化學的) 변화(變化) 및 당금기간(其間)에 대(對)하여)

  • Chang, Chi-Hyun
    • Applied Biological Chemistry
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    • v.6
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    • pp.8-13
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    • 1965
  • Korean MEJUES were prepared by means of ordinary, Improved and compromised methods, and analyses of the changes in various chemical compositions of the Soy-sauces throughout the fermentation period of 10 weeks. Now, their result, are as the following as. (1) In all of the Soy-sauces under study the content of organic acids showed a slight increase upto 4 week, and a marked increased after this period. (2) In all of the soy-sauces the total nitrogenous content indicated a rapid increase until 4 weeks, and a slower increase after this. (3) In all of the soy-souses, the content of free amino acids displayed a liner proportional increament until 8 weeks and then slower increose. (4) In all of the soy-souses the content of reducing sugars indicated a slight increase until 4 weeks, and after this it showed a rapid decrease until 4 weeks, in the improved soy-souses and, then maintained an almost flat curve. In the ordinary and Compromised soy-souses there was a rapid decrease in reducing sugars until 6 weeks, and then an almost 리at curves. (5) In the ordinary soy-sauce the SAMWOL-ZANG-BUB(soy-sauce prepared in March) is considered to be based on a comparatively scientific ground during the fermentative period. (6) In order to improve the taste in ordinary soy-sauce it is favorable to delay the period of preparation. The adequate period appears requires 8 weeks at least. Accordingly it is recommended to mix the materials with carbohydrate source. (7) In the improved soy-sauce according to the SAMWOL-ZANG-BUB of ordinary soy-sauce it is thought that 8 weeks were adequate for the fermentation. (8) The compromised method may be recommended for the improvement of nomemade soy-souce, and it may be also superior to the ordinary soy-sauce in quality.

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Changes in Physicochemical and Antioxidant Properties of by Enzyme-Treated Super Sweet Corn Extracts (효소처리에 의한 초당옥수수 추출물의 이화학적 및 항산화 특성의 변화)

  • Byung-Ho In;Da-Bin Jang;Jae-Jun Lee;Won-Jong Lee;Ah-Reum Yoon;Sung-Kyu Kim;Kyung-Haeng Lee
    • The Korean Journal of Food And Nutrition
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    • v.36 no.6
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    • pp.526-534
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    • 2023
  • To improve usability of super sweet corn, extracts were prepared with hydrolytic enzyme and changes in physicochemical and antioxidant properties were analyzed. Soluble solids and reducing sugars contents were higher in all enzyme treatment groups than in the control. When enzyme treatment time increased, contents of soluble solids and reducing sugars were also increased. There was no significant difference in lightness between treatment groups, with redness showing the highest value in the control and yellowness showing the highest value in the invertase treatment group. Free sugar content in the control was the lowest. However free sugar content in the enzyme combination treatment group was increased by more than four times compared to that in the control. Contents of ascorbic acid, flavonoids and polyphenols were higher in the enzyme treatment group than in the control. In particular, the enzyme combination treatment group showed the highest content. DPPH and ABTS radical scavenging abilities were significantly higher in all enzyme treatment groups than in the control. Radical scavenging abilities of cellulase treatment group and enzyme combination treatment group showed high activity. The activity increased when enzyme treatment time increased. The combined enzyme treatment method for super sweet corn was suitable for food processing.

Food Nutritional Composition in Dried Powder of Root of Acorus calamus L. ( I ) Pyoximate Compositions, Sugars, Free Sugers and Amino Acids (창포(Acorus calamus L.)뿌리 건조분말의 식품학적 성분 (I) 일반성분, 총당, 환원당, 유리당 및 아미노산)

  • 김준한;구건효;문광덕
    • Food Science and Preservation
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    • v.9 no.4
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    • pp.375-379
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    • 2002
  • This study has been carried out to investigate the food chemical composition in dried powder of main and lateral root of Acorus calamus L. Content of crude protein and crude fat in dried powder of main and lateral root were 12.76% and 9.84%, 7.43% and 3.42%, respectively. Total and reducing sugar of main and lateral root were 21.99% and 7.67%, 24.12% and 0.65%. Major free sugars of root were sucrose, stachyose, raffinose, glucose and fructose. Sucrose of main and latent not were found to be the most predominant free sugars, contained 10.85 % and 1257%. Content of total amino acid were 427 mg% of main mot and 470 mg% of lateral root. Major total amino acids of root were arginine, glutamic acid, major free amino acids of main and lateral root were detected asparagine, arginine, glutamic acid and phenylalanine, respectively. Among the essential amino acids, the content of threonine was the highest (15.62 mg%) in main root and phenylalanine was the highest (12.67 mg%) in lateral root.

Effect of pH on the Enolization of Sugars and Antioxidant Activity of Caramelization Products Obtained by Caramelization Browning

  • Kim, Ji-Sang;Lee, Young-Soon
    • Food Science and Biotechnology
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    • v.17 no.5
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    • pp.931-939
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    • 2008
  • The objective of this study was to investigate the enolization reaction and the antioxidant activity of caramelization products (CPs) obtained by caramelization browning of glucose and fructose solutions prepared at a pH ranging from 7.0 to 12.0 at varying temperatures ($80-180^{\circ}C$). The degradation of sugars rapidly increased at a high alkaline pH (10.0-12.0), and fructose degraded more rapidly than glucose (p<0.05). As the pH increased, the degree of sugar enolization was higher in fructose than in glucose. Browning and the formation of intermediate degradation products increased with the increase in heating temperatures. The browning development was dependent upon the type of sugar, and it was generally higher at alkaline pH than at neutral pH. The reducing power and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the CPs increased with the increase in browning and formation of large amounts of intermediates. Therefore, the CPs with pronounced antioxidant activity can be prepared by heating fructose or glucose solutions that have a very alkaline pH to high temperatures.

Quality Characteristics and Antioxidant Activities of Rehmannia glutinosa JungKwa Prepared with Different Kinds of Sugars (당종류를 달리하여 제조한 지황정과의 품질특성 및 항산화성)

  • Kim, Hyun Jeong;Min, Sae Rom;Kim, Mee Ree
    • Korean journal of food and cookery science
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    • v.30 no.1
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    • pp.76-83
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    • 2014
  • In this study, we have investigated the quality characteristics and antioxidant activities of Rehmannia glutinosa JungKwa (RJ) prepared with different types of sugars (sucrose, isomalto-oligosaccharide, honey or sorbitol). Moisture content was the highest in RJ with honey. The pH level was the highest in RJ with sorbitol, whereas the acidity is the highest in honey. The reducing sugar content is the highest in RJ with honey. The L and a values of Hunter color system showed the highest in RJ with honey, while the b value the highest in RJ with sorbitol. The hardness of texture profile analyses represented the lowest in RJ with sorbitol. Sensory results showed that RJ with sugar was the best in the sensory preference test. The total phenol content was the highest in RJ with honey, while the lowest in RJ with sorbitol. The antioxidant activity determined by $IC_{50}$ values of DPPH and hydroxy radical scavenging activities was the highest in RJ with honey. From these results, it was suggested that RJ with honey show the highest antioxidant activity.