• Korean Journal of Food Science and Technology
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• v.18 no.5
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• pp.364-371
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• 1986

High-ester pectin was demethylated by the treatments of HCl alone and a combination of HCl and $NH_4OH$. The low-ester pectin prepared were analyzed for chemical composition and the pectin gels were evaluated for firmness by sag values and strength by puncture stress. Gels made from HCl demethylated sample showed brittle, weak and poor elastic characteristics while the $HCl-NH_4OH$ treated samples generally resulted in a smooth and elastic gels except those samples having very low content of ester group or acid amide group. Statistical analysis showed that significant correlations were found between sag values and ester content or molecular weight, and puncture stress and ester content, acid amide groups or molecular weight. The equations derived for sag, puncture stress and sag/puncture stress from chemical data could be useful for prediction of some of the physical properties of low-ester pectin gel.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.156-163
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• 1999

This study was evaluate of chemical properties. textural charact6eristics and sensory properties prod-uced peach pyuns through the change of gelling agents such as mungbean starch potato starchy and pec-tin and of sugar density with 10%, 20%, and 30%. Sensory evaluation was that peach pyun added mun-gbean starch was more preferable in appearance and texture than peach pyun added potato starch. Peac-h pyun added 0% pectin was more preferable than peach pyun with 1% pectin. As a result of texture analysis the texture of peach pyun added mungbean starch was denser than that added potato starch. Adding 1% pectin to peach pyun increased mechanical properties such as hardness and chewiness. Mun-gbeaan starch pyun with pectin on lightness Potato starch pyun with pectin on redness and potato star-ch pyun with pectin on yellowness were significant(p<001). Lightness has a tendency to decrease with increasing sugar density. Adding 1% pectin has the effect to increase lightness redness and yellowness. The subject parameters that effect overall quality on sensory evaluation were found taste quality tex-ture quality hardness adhesiveness and taste by using regression analysis.

• Korean journal of food and cookery science
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• v.8 no.3
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• pp.281-289
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• 1992

The physicochemical, rheological and sensory characteristics of Backsulgies added with dietary fibers-cellulose, pectin and wheat bran-were investigated. The maximum acceptable ratio of fibers was 10% for wheat bran or cellulose, 3% for pectin. As me results of physicochemical analysis, cellulose and pectin had larger water-binding capacity man wheat bran. Swelling power was increased with temperature increment. But the type of added dietary fiber did not make significant differences. The degree of gelatinization was measured by maltose content. The retrogradation of backsulgies was significantly delayed by the addition of dietary fibers. The retardation effect of dietary fibers for retrogradation of backsulgies was also proved by textural analysis and time constant determination of Avrami equation. Pectin had especially excellent delaying effect while me storage time extended. There were no significant differences in sensory characteristics between me backsulgi with no dietary fibers and backsulgies added with cellulose 3%, pectin 1% and wheat bran 3%. Therefore, we concluded mat cellulose 3%, pectin 1% and wheat bran 3% were me optimum addition ratios, which have the delaying effect of retrogradation, and which could be accepted as same as conventional backsulgies organoreptically.

• Preventive Nutrition and Food Science
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• v.15 no.1
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• pp.57-66
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• 2010

Passion fruit fiber pectin gels represent a new alternative pectin source with potential for food and non-food applications on a commercial scale. Pectic polysaccharides were extracted from passion fruit (Passiflora edulis) fiber using citric acid as a clean catalyst and autoclaved for 20 to 60 min at $121^{\circ}C$. The best condition of pectin yield with the highest molecular weight was obtained with 1.0% of citric acid (250 mg/g dry passion fruit fiber pectin) for 20 min of autoclaving. Spectroscopic analyses by Fourier transform infrared, enzymatic degradation reactions, and ion-exchange chromatography assays showed that passion fruit pectin extracted for 20 min was homogeneous high methoxylated pectin (70%). Gel permeation analysis confirmed that the pectin extract obtained by autoclaving by 20 min showed higher molecular weights than those autoclaved for 40 and 60 min. Passion fruit pectin extracted for 20 min was enzymatically modified with fungal pectinmethylesterase to create restructured gels. Short autoclave treatment (20 min) with citric acid as extractant resulted in a significant increase of gel strength, improving pectin extraction in terms of functionality. The treatment of solubilized material (pectic polysaccharides) in the presence of insoluble material (cellulose and hemicellulose) with pectinmethylesterase and calcium led to the creation of a stiffer passion fruit fiber pectin gel, while syneresis was not observed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.4
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• pp.500-509
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• 1993

Pectins present in the primary cell walls and middle lamellae of plant cell walls are extracted by water, cheating agents, acid or alkali solutions. However, some neutral contaminating components are extracted in conjunction with pectins during the extraction process. Thus, the accurate characterization of physi-cochemical properties of pectins necessitates to get rid of the impurities. In this review, dialysis, alcohol precipitation, ion exchange chromatography and metal precipitation were compared as procedures to purify the pectin extracts. In addition, the chemical methods to analyze pectins are discussed in terms of three major chemical constituents, i.e., anhydrogalacturonic acid, methoxyl groups and neutral sugars.

• Korean journal of food and cookery science
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• v.7 no.2
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• pp.19-23
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• 1991

This study was conducted to compare the characteristics of reference starch gel and 5 additives-adding corn starch gels (agar, CMC, pectin, casein, gelatin). The sensory evaluation, textural analysis by Instron Universal Testing Machine were carried out The results were as follows: 1. In sensory evaluation. \circled1 The hardness of agar was significantly higher than that of control and the hardness of pectin was significantly lower than that of control. \circled2 The adhesiveness of CMC and pectin was significantly higher than that of control, and the adhesiveness of agar was significantly lower than that of control. \circled3 In acceptability, CMC and pectin were significantly higher than control and the other samples were not significantly different from control. 2. In textural analysis by Instron. \circled1 The hardness of agar was significantly higher than that of control and the hardness of the other samples was significantly lower than that of control. \circled2 The cohesiveness of agar and casein was significantly higher than that of control and the cohesiveness of gelatin was significantly lower than that of control. 3. In sensory evaluation or instrumental analysis by Instron. It was thought that the best sample-classifying characteristic was hardness.

• Korean journal of food and cookery science
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• v.2 no.1
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• pp.65-70
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• 1986

Total pectin content of Korean apple varieties at optimum harvest time was deter-mined by carbazole reaction method and pectin fraction content in each variety was also determined. Properties of pectin extracted ty 2a Sodium hexa metaphesphate were compared with commercial pectin. Among apple varieties, pectin contents varied in the range of 0.26-0.48％ on fresh basis and 1.76-4. 0% on dry basis. Ball's was the highest and then high in order of Spur early blaze, Golden delicious, Fuji. , Jonathan. In each pectin fraction, soluble pectin fractions in Rall's was the lowest and in both Spur early blaze and Golden Delicious were highest but insoluble fractions in the latter were lowest. Thub the changes in poetic substances in Spur early blaze and Golden delicious seem to he occurred: during early ripening. In the analysis of properties of isolated pectin, ash, anhydrogalacturonic arid7(AUA) content and methoxyl content were different among apple varieties. Ash and methoxyl content in all isolated pectin were higher and AUA content lower than in commercial pectin. Degree of esterification (DE) in all apple varieties were above 70％.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.429-438
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• 2003

The optimization of Omija-pyun as a traditional dessert, with the most European taste and year round availability, was studied with regard to its texture. The response surface methodology was used to determine the optimal composition of Omija-pyun as a European style dessert. The texture, including the springiness, gumminess, cohesiveness, adhesiveness, hardness and chewiness, was measured using TPA parameters (TA-HD Texture Analyser, stable micro system, UK). The texture of Omija-pyun was influenced by pectin and sucrose to the first linear order. The properties of springiness and adhesiveness were influenced by pectin x pectin to the second quadratic order. No cross product effects between ingredients were found from the analysis. The maximum springiness was obtained with 42g of pectin, 450g of sucrose, 110g of glucose syrup and 4.8g of tartaric acid. The maximum chewiness was with 55g of pectin, 330g of sucrose, 140g of glucose syrup and 5.7g of tartaric acid. The maximum adhesiveness was achieved using 17g of pectin and 400g of sucrose. The gumminess and hardness increased with increasing pectin content, and a cross product effect was observed(Eds note: you said earlier that no cross product effects between the ingredients was found\ulcorner) between sucrose and glucose syrup.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.396-402
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• 1999

To increase the utilization of citron(Citrus junos), manufacturing conditions of citron jelly were studied. Citron extract was diluted 7 fold for jelly processing and it's pH was 2.64. Due to the low pH of citron extract, 2.5∼3.0% of pectin was added which was slightly higher than the amount for ordinary jelly process. To reduce the loss of citron flavor and vitamin C, it was heated for 10 min. and found to be enough for proper hardness of jelly. Agar and gelatin was used as jellying agents to improve the physical properties of pectin jelly. From the result of compression curve analysis, addition of 5% and 7% of gelatin were more effective in jelly texture than agar in 1.5% and 2.5% pectin jelly, respectively. Sucrose was replaced by glucose and oligosaccharide; galactooligosaccharide, fructooligosaccharide and isomaltooligosaccharide. From the sensory evaluation analysis, 30% of sucrose and 30% of isomaltooligosaccharide in jelly was evaluated as superior to other sugars.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.289-292
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• 1993

The effect of sugar alcohols in the preparation of acceptable low methoxyl pectin(LMP) jellies were studied. Sensory scores analysis, Hunter's color parameters and texture profile analysis using universal testing machine were performed. The composition of sweetners used in this study were 100％ sucrose, 75％ sucrose and 25％ maltitol, 50％ sucrose and 50％ maltitol, and 50% sucrose, 25％ maltitol, 12.5％ sorbitol'and 12.5% mannitol. LMP jellies with 100％ sucrose showed the strongest sweetness among them. Other sensory characteristics of LMP jellies were regarded as same. Hunter's value of lightness, redness and yellowness of 100％ sucrose jellies and jellies substituted with maltitol up to 25％ were not significantly different, but those of LMP jellies substituted with 50％ sugar alcohols were higher(p<0.01) than other 3 types of jellies. As substitution ratio was increased, springiness and chewiness were lower(p<0.01). Fracturability(p<0.01) and hardness(p<0.05) of jellies made of 100% sucrose and 75％, sucrose and 25% maltitol showed higer value than the other jellies. Springiness of jelles sweetened with sucrose and 3 sugar alcohols was the highest(p<0.05). Replacement of sucrose by sugar alcohol did not influenced on gumminess and cohesiveness of LMP jellies.