• Korean journal of food and cookery science
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• v.33 no.3
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• pp.300-306
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• 2017

Purpose: This study aimed to prepare sea tangle vinegar and test its applicability as a vinegar-based functional salad dressing in terms of physicochemical properties. Methods: Sea tangle vinegar was prepared by mixing sea tangle with sugar and vinegar and fermenting the mixture at room temperature for 3 months. The resulting sea tangle vinegar was examined for its physicochemical properties and antioxidant activity with brewed vinegar and persimmon vinegar as controls. Results: The sea tangle vinegar showed significantly higher viscosity than control vinegars, and shear thinning behavior that is typical for salad dressing containing polymers. In addition, storage modulus (G′) of sea tangle vinegar was relatively high in dynamic viscosity measurement while that of control vinegars remained negligible. Together with the high soluble solids content of sea tangle vinegar, rheological behavior indicates that sea tangle vinegar had soluble polysaccharides extracted from sea tangle, consequently leading to an increase in viscosity. Titratable acidity (TA) and pH were 2.52% and 3.58, respectively, which satisfies the TA and pH requirements for microbiological safety of a salad dressing. Absorbance at 285 nm and Folin Ciocalteu's reagent method revealed that sea tangle vinegar contained antioxidative phenolic compounds. Conclusion: This study demonstrates that sea tangle vinegar could be potentially developed as a vinegar-based functional salad dressing when combined with sensory evaluation in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.821-826
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• 1998

Functional properties of mucilage and pigment extracted from Opuntia ficus-indica var. saboten were determined at various temperatures, pHs and alcohol concentrations. The crude mucilage extracted from pickly pear showed pH 4.2, 0.14% total acidity and 8.1% total soluble solid content(w/w, wet basis). Polysaccharide was purified from mucilage extract by isopropanol precipitation. Intrinsic viscosity of polysaccharide was 18.1dl/g and decreased with increasing KCl concentration. Relative viscosity and color stability of mucilage extract were determined with capillary viscometer and spectrophotometer at 534nm, respectively. In additions of 1~20%(v/v) ethanol, the red pigment of mucilage extract was very stable, but relative viscosity, increased gradually. For heating above 7$0^{\circ}C$, the stability of red pigment decreased drastically, but rheological property of mucilage was not changed. During storage, the red pigment was extremely unstable at above pH 8.3. At both pH 3.0 and pH 4.2, the red pigment was the most stable at 4$^{\circ}C$ for 18 days. In the case of storage at 37$^{\circ}C$, pigment of mucilage extract at pH 3.0 was destroyed more quickly than that at pH 4.2. Natural mucilage extract(pH 4.2) showed the good stability of red pigment at 3$0^{\circ}C$ for 10 days.

• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.124-130
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• 2008

In order to fabricate a modified poly (lactic acid) (PLA) for applications requiring high melt strength, a PLA has been irradiated in the presence of functional monomer of glycidyl methacrylate (GMA). Samples were prepared with various contents of GMA and irradiation dosages, and were characterized by observing their thermal and melt viscoelastic properties and gel faction. The complex viscosity and storage modulus of the modified PLA without GMA were lower than those of the original PLA. Those of the modified PLA decreased with increasing dosage. In the case of the modified PLA containing 0.1 phr or 0.3 phr of GMA, their changing tendency with dosage was similar to the irradiated PLA without GMA. However, the 5 kGy irradiated PLA containing 0.5 phr of GMA showed the greatly enhanced complex viscosity and storage modulus, which were about 3 and 10 times higher than those of the original PLA at a frequency of 0.1 rad/s, respectively.

• Clean Technology
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• v.15 no.2
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• pp.102-108
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• 2009

In this study, poly(lactic acid) (PLA) was modified by reactive extrusion with a functional monomer GMA(glycidyl methacrylate), MMT(montmorillonite), and initiator to enhance the melt strength. Each modified PLA was prepared with different amounts of GMA and MMT and was characterized by measuring thennal- and melt-viscoelastic properties. The degree of dispersion of MMT was measured by X-ray diffraction(XRD) and transmission electron microscopy(TEM). The glass transition temperature($T_g$) of modified PLA-GMA-MMT nanocomposite decreased with increasing GMA content, but was a little affected by the amount of MMT. Surface analysis showed that the nanocomposite became more intercalated than exfoliated as the amount of MMT increases. The complex viscosity and storage modulus of the nano-composite were greatly increased by addition of MMT.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.434-440
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• 2013

Functional properties of Cheonnyuncho fruit paste (CFP) were enhanced by fermentation, using Leuconostoc mesenteroides SM. The stability of CFP pigment was maintained and microorganisms in crude CFP were sterilized by heating at $80^{\circ}C$ for 30 min. The production of dextran in CFP was increased by increasing the fermentation time and sugar content, resulting in an increase of consistency. The CFP fermented with 20% sucrose contained 4.8% mucilage after fermentation for 2 days. In particular, the production of mucilage was greatly enhanced by fortification with 3% sodium citrate in CFP, resulting in mucilage production of 7%. In addition, the viscous modulus of fermented CFP showed a greater increase than that of the elastic modulus. Thus, it was concluded that CFP fermented by L. mesenteroides SM can be fortified with functional ingredients, such as mucilage and probiotics, with enhanced rheological properties. Therefore fermented CFP can be utilized as the functional ingredients for functional foods.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.640-645
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• 1995

Job's-tears(Coix lachryma-jobi L. var. Ma-yuen Stapf) seeds were processed to flakes by soaking, heat treatment, intermediate-moisture drying, flaking, drying, and cooking. Some functional properties of job's-tears flakes subjected to varing degree of heating were characterized by specific volume, texture, water absorption index(WAI), water solubility index(WSI), and viscosity. As degree of gelitinization increased within the intermediate range of $60{\sim}70%$, steam-cooked Job's-tears demonstrated appropriate rheological properties for further processes, resulting in increased specific volume and decreased breaking strength. However, excessive heat treatment rendered Job's-tears undesirably sticky for flaking, which caused adverse effects on the functional properties of flakes such as specific volume and breaking strength. Increasing steaming time$(5{\sim}30\;min)$ caused an increase in WAI and WSI values. Apparent viscosity of powdered flakes was increased with the extent of gelitinization as a function of heat processing. Viscosity of powdered flakes determined using the amylograph increased with the degree of heating applied to Job's-tears at low pasting temperatures, accompanied by a decrease in maximum viscosity as the pasting temperature increased.

• International Journal of Highway Engineering
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• v.16 no.5
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• pp.9-18
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• 2014

PURPOSES : The objective of this study is to evaluate the applicability of the pitch, which is produced during SDA petroleum upgrading process, as a pavement paving material. In order for the purpose, the physical and chemical properties of the pitch are analyzed, and then the various plasticizers are applied in the pitch. METHODS : Two types of pitch are selected from oil refinery companies, which are owned the SDA petroleum upgrading process. Also, two types of asphalt binders, PG 64-22 and PG 58-22, are employed to compare with the pitch because these two types of asphalt binders are currently used as paving materials. For the chemical property of the pitch, the composition of SARA (Saturate, Aromatic, Resin, Asphaltene), the elementary composition, and the functional group are analyzed. For the physical property of the pitch, the basic material property tests, such as penetration test, softening point test, flash point test, ductility test, and rotational viscometer test, are performed. Also, the DSR (Dynamic Shear Rheometer) test and the BBR (Bending Beam Rheometer) test are conducted using asphalt binder specimens obtained by both short term aging (Rolling Thin Film Oven, RTFO) and long term aging (Pressure Aging Vessel, PAV) processes. The rheological property of each pitch type is evaluated as a function of temperatures and loading cycles. PG 64-22 asphalt binder is used as a control material. RESULTS AND CONCLUSIONS : The Pitch may not be suitable for the pavement paving material without modifications, but the pitch can be used as alternatives of modified addictive or asphalt. If low molecular component, such as saturate and aromatic components, are added in the pitch based on the development of various plasticizers, it has a strong possibility for the pitch to be used as a alternative. However, in order to verify the performance property of the pitch, further research is needed.

• Journal of the Korean Society of Food Culture
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• v.21 no.6
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• pp.695-701
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• 2006

This study is based on the utilization of pine mushroom for processing products by development of pine mushroom Jung-Gwa. The results were summarized as follows: Pine mushroom Jung-Gwa were prepared with four different amounts (20, 30, 40, 50%) of honey. Pine mushroom Jung-Gwa color value was the highest by 20% soaking honey-water product and 40% soaking honey-water product was the lowest. Strength and hardness of 20% soaking honey-water product was the highest. Appearance to product of 50% soaking honey-water was the highest preference by all age of except 20's. The honey content of more and more external appearance preference was became higher. Product of 40% soaking honey-water was best by flavor of pine mushroom Jung-Gwa. A sugary tastes comparison 50% soaking honey water to 40% soaking honey water was not distinction. The texture was appeared a statistically significant difference by products of 20%, 30% soaking honey-water. Product of 20% soaking honey-water was favorite in 20's and product of 30% soaking honey-water was favorite in 30's. In overall preference test for pine mushroom Jung-Gwa of 40% soaking honey water was preferred by all age. Oligosaccharide helped geriatric diseases and cheaper. Thus this study used oligosaccharide but the result was not a statistically significant difference of pine mushroom Jung-Gwa products quality by comparison honey-water to oligosaccharide. Therefore oligosaccharide utilization products was thought worth a lot more by processing price and functional.

• Food Science of Animal Resources
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• v.39 no.1
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• pp.23-34
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• 2019

Fat reduction in the formulation of cheese emulsion causes problems in its flowability and functional characteristics during spray-dried cheese powder production. In order to eliminate these problems, the potential of using microparticulated whey protein (MWP) in cheese emulsions was examined in this study. Reduced-fat white-brined cheese emulsions (RF) with different dry-matters (DM) (15%, 20%, and 25% excluding emulsifying salt) were produced using various MWP concentrations (0%-20% based on cheese DM of emulsion). Their key characteristics were compared to full-fat cheese emulsion (FF). MWP addition had no influence on prevention of the phase separation observed in the instable group (RF 15). The most notable effect of using MWP was a reduction in apparent viscosity of RF which significantly increased by fat reduction. Moreover, increasing the amount of MWP led to a decrease in the values of consistency index and an increase in the values of flow behavior index. On the other hand, using high amounts of MWP made the emulsion more liquid-like compared to full-fat counterpart. MWP utilization also resulted in similar lightness and yellowness parameters in RF as their full-fat counterparts. MWP in RF increased glossiness and flowability scores, while decreased mouth coating scores in sensory analyses. Fat reduction caused a more compact network, while a porous structure similar to FF was observed with MWP addition to RF. In conclusion, MWP showed a good potential for formulation of reduced-fat cheese emulsions with rheological and sensorial characteristics suitable to be used as the feeding liquid in the spray drying process.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.234-240
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• 1997

Agar has widely been used as medical aids and food ingredients due to its pecular physicochemical and rheological properties. In this paper, the effects of spray drying and extrusion drying on functional properties of agar were investigated to clarify the sol-gel transition mechanism at low temperature and microstructure of agar gel by measuring phase transition by differential scanning calorimetery, structural differences by light microscope and scanning electron microscope observation. The lowest endothermic onset(To), peak(Tp), conclusion(Tc) temperature and enthalpy($\Delta$H) using differential scanning calorimetery were showed in extrusion-dried agar wic were checked in 41.30, 61.72, 80.50 and 0.73cal/g. In cases of unmodified and spray-dried, the values were 81.20, 95.51, 112.14 and 3.22cal/g, and 60.11, 76.45, 89.54 and 1.53cal/g, respectively. When all samples were reheated using differential scanning calorimetery after gelling fully, no significant differences of endothermic To, Tp, Tc and $\Delta$H appeared. The surface structure of unmodified agar powder observed by light microscope and scanning electron microscope appeared a continuous surface without any indication of small pores, gaps or point of discontinuity. In cases of spray-dried agar, the unstable structures with pores was resulted. The microstructures of extrusion-dried agar, however, was solid with large gaps and areas of discontinuity in the surface. From the results above, it was suggested that significant differences in phase transition and surface microstructures were clearly related to the physicochemical changes and rheological properties, solubility and gelling ability of the types of agar gel.