• Journal of agriculture & life science
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• v.46 no.6
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• pp.117-126
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• 2012

This study carried out on the manufacturing of pidan. The production of pidan can be one of solutions for over-produced eggs and stable egg price. For the alkali-pickling solution for manufacturing of Pidan, the tested concentration of NaOH and NaCl were respectively as 3, 5, 7% and 5, 10, 15, 20%, and examined every 2 days for 14days. According to the results, pH value of alkali-pickling solution was increased by the increment of NaOH concentration and the pickling period, and was decreased by the increment of NaCl concentration. The pH value of egg yolk was increased by the increment of NaOH concentration, but it was not significantly different by the NaCl concentration. By the increment of NaOH and NaCl concentrations, the alkali infiltration in egg yolk and egg white was accelerated. Furthermore, the weight change of the eggs in the alkali-solution has no effects on manufacturing of Pidan. Liquefied albumen showed significant differences by NaOH concentration rather than that of NaCl. There was no liquefied albumen for 14days at 3% of NaOH, but it was found between 11-12days at 5% and 8-10days at 7%, respectively. The pH values of egg white when it was liquefied albumen were between 11.8 and 12.0. Pidan was made by heat treatment after 6-7days dipped in the solution at the concentration of 7%, about 10days at 5%, and 12-14days at 3% of NaOH, respectively. Although, the period of manufacturing of Pidan was saved by the increment of NaOH concentration, liquefied albumen was accelerated and the food preference was decreased by ammonia odor. Therefore, the suitable concentration of NaOH is between 3 and 5%, and that of NaCl is between 5 and 10% due to the effect of salinity by the soaking period. Through this study, optimal pickling solution and dipping time for manufacturing of Pidan was figured out, and also find out that it can save a time about 15days for manufacturing of Pidan.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 1993.12a
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• pp.6-9
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• 1993

According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. According to changes in population, economic conditions, life-stile and eating habits, the frui ts and vegetables market wi 11 be shi fted from processed (i. e. , canned) to fresh. Undressed fresh produce, consisting of washed, disinfected and peeled fruits and vegetables that either sliced or grated, are currently increased in demand by retail and institutional market which use them as salad components or in ready-to use foods, Main attributes of minimally processed fruits and vegetables are convenience and fresh-like quality. Minimally processed Products readily deteriorate in quality, especially color and texture, as a result of endogeneous enzyme enhanced respiration and microorganisms which lead to reduced shelf Iife. Thus. to prevent these undesirable changes , val'ious techniques such as controlled atmosphere (CA) storage, modified atmosphere OIA) storage, including vacuum packaging have been receiving considerable attention, Although milch research has been done to find optimal conditions for whole intact frui ts and vegetables, only limi ted information is avai lable on fresh cut. and other minimally processed products. 81 iced frui ts exhibi t increas~d ethylene production and respiration compal'ed to whole f, 'uits during distribution in response to tissue damage. As a result, accelerated senescence and enzymatic browning OCCUI', Recent l'esearch on minimally processed fl'uits and vegetables has mainly focused on methods to inhibit browning, due to ban on use of sulfur dioxide, In order to retard or prevent these physiological changes, val'ious al ternatives, reducing agents. acidulants, chelating agents and inol'ganic sal ts have been evaluated for use on fresh cut fl'ui ts. Al though some agents were effective replacement for sulfur dioxide. consum$\textregistered$I'S demandless use of chemical on such products. Shel~ life of minimally processed products has been extended by inhibition of metabolic reactions associated with loss of quality and by inhibition of aerobic spoilage caused by wide variety of microorganisms. Appl ication of ~I.-\ packaging, including vacuum packaging, retards the rate of respiration, prevents growth of aerobic spoilage organisms, inhibits oxidation and color deterioration. Tissue softening is another major problem in minimally processed products because enzymes re 1 a ted to ce 11 wa 11 degrada t i on are not inactivated. Various treatments have been investigated for retardation of the softening of sliced products. Some studies have concentrated on the application of an active packaging system with ~I, l. packaging and calcium infi 1 tration as possible measures to retain firmness of processed products. In my opinion, one important step for production of minimally processed frui ts wi th favorabl e color of cut surface and firm texture is the selection of better cultivar. As the view, changing tendency of fresh color by apple cultivars and relationship between the tendency and PPO activity will be discussed in the seminar. In addition to the topic, research result on quality enhancement of fresh apple slices by heat shock treatment will be introduced.