• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.7
• /
• pp.1011-1017
• /
• 2010

Sunflower oil (SO), canola oil (CO) and frying oil (FO) were used as edible oils in this study. According to the frying number, the extracted oils from French fried potatoes were used as experimental samples. To investigate the relationship between the change of fatty acid composition and the stability of the lipid oxidation during frying, the changes of fatty acid composition and the degree of the lipid oxidation of samples were examined. Acid values and peroxide values were evaluated as the degree of lipid oxidation. The acid values of CO and FO were increased with the frying times. The increased acid values of CO and FO were 0.20 and 0.17 on the basis of initial value at 30 times, respectively, but the acid value of SO was lower than those of CO and FO. The peroxide values of the samples were not increased uniformly with the frying number. As the number of frying times was increased, the fatty acid composition of SO and FO were changed. Namely, the oleic acid composition was decreased, whereas the linoleic acid composition was increased with the number of frying times. The benzo(a)pyrene contents of the extracted oils from French fried potatoes did not change regularly as the frying times was increased.

• Applied Chemistry for Engineering
• /
• v.4 no.4
• /
• pp.823-829
• /
• 1993

The basic medium oil modified alkyd resin was synthesized from linseed oil fatty acid(LOFA), phthalic anhydride(PAA), trimellitic anhydride(TMA ), and trimthylol propane(TMP) by condensation polymerization at $230^{\circ}C$. TMPTA modified water-reducible alkyd resins were synthesized with TMPTA graft copolymerization onto the basic resin at $180^{\circ}C$. Acid value of the resin was controlled by the addition of TMA and N,N-Dimethylethanol amino(DMEA) was used as an neutralizing agent to prepare water-reducible alkyd. To evaluate the optimum formulation for anionic alkyd resin, water proofness and water reducibility were estimated from the acid value or TMA contents. The effect of TMPTA on the graft copoymerization of the resin was studied by measuring molecular weight, glass transition temperature(Tg), viscosity, and gel contents. The suitable balance of water proofness and water reducibility of the resin was obtained at range of 5.3~7.0wt.% of TMA contents or 40~50 of acid value of basic resin. The molecular weight, viscosity, and gel contents of water-reducible alkyd resin were increased according to the TMPTA graft copolymerization, but Tg was decreased.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.18 no.1_2
• /
• pp.21-25
• /
• 2012

This study was conducted to investigate the effects of filling and packaging temperatures on the quality changes of retorted Samgyetang during storage. The samples were manufactured after filling the broth maintained either at $50^{\circ}C$ (T1) or $85^{\circ}C$ (T2) into pouch and followed by sterilizing them at $120^{\circ}C$ for 65 min under the F value of approximately 8.0. The samples were stored at $25^{\circ}C$ up until 6 months and various physic-chemical parameters including pH, oxygen ratio in the headspace of package, residual dissolved oxygen concentration in the broth, acid value, volatile basic nitrogen value (VBN), apparent viscosity, spreadability of porridge, and sensory attributes were analyzed periodically at month 0, 1, 3, and 6, respectively. During storage time, the dissolved oxygen concentration and acid values of T2 samples tended to increase slower than T1 (p<0.05). Between T1, and T2 samples, significant differences were observed for pH and dissolved oxygen concentration over the storage period while acid values and VBN values were significantly different from 3 months (p>0.05). Contrarily, no apparent differences were observed between two samples in the apparent viscosity, spreadability of porridge, and sensory attributes over the storage period (p>0.05).

• Korean Journal of Food Science and Technology
• /
• v.49 no.1
• /
• pp.50-55
• /
• 2017

The purpose of this study was to investigate the effect of frying number on oxidative changes in edible oils and fried foods. According to the frying number, the extracted edible oils from pork cutlet and fried potato were used as experimental samples. The Ministry of Food and Drug Safety (MFDS) regulations permit edible oils to have <2.5 mg KOH/g of acid value and <50 meq/kg of peroxide value in food. However, there are no regulations for edible oils used to fry livestock. Animal foods contain protein and fat, and should be held to a different standard than ordinary food. Therefore, we present basic information and suggest the establishment of regulations for livestock frying oil and fried livestock.

• Current Research on Agriculture and Life Sciences
• /
• v.6
• /
• pp.121-127
• /
• 1988

Ramyon(deep fat fried instant noodle with palm oil) preserved in sunlight, room temp. ($20{\pm}5^{\circ}C$), incubator ($30{\pm}2^{\circ}C$) and corrugated fiber board box to investigate the oxidative changes of the Ramyon lipids. In the study, changes in acid value, peroxide value, carbonyl value, TBA value, fatty acid composition, iodine value and panel test were determined with the lipids extracted from the Ramyon samples in intervals for a period of 20 weeks. Acid value, peroxide value, carbonyl value and TBA value of the Ramyon lipid were increased slightly during the storage in aluminum foil package in the corrugated fiber board box in the dark room. They did not appear the oxidative rancid odor at the end of 20 weeks storage. Acid value, peroxide value, carbonyl value and TBA value of the samples under room temp., incubator slightly during storage, while a sharp increase of those values were noticed with the samples of sunlight. Especially, the TBA value of the Ramyon lipid under sunlight markedly increased within 14 weeks and then decreased. Oxidative rancid odor appeared at the end of 10 weeks storage under sunlight, while it took 18 weeks with the sample stored under room temp. and incubator. During the storage under incubator and sunlight for 18 weeks, the content of oleic, linoleic acid decreased, while palmitic and stearic acid increased. However, only small changes were noticed in iodine value of the samples.

• Journal of the Korean Society of Food Culture
• /
• v.20 no.5
• /
• pp.627-631
• /
• 2005

Deodorized soybean oils(DSO) were obtained to 2 types. Sample 1 was carried out a general refining process, which was degumming-alkali refining-bleaching-deodorizing. Sample 2 and 3 were not general refining process, its were carried out only both decantation of insoluble impurities and batch type deodorizing(BTD). At this time, BTD was composed of 3 stages, operating differences were vacuum degree, maximum temperature, stripping steam and retention time etc. DSO obtained were appeared original physicochemical characteristics. Sample 1 had acid value 0.034, Lovibond color, 9.1Y/0.9R, peroxide value 0 and thin yellow color's soybean oil. But sample 2 had acid value, 0.078, Lovibond color, 65.0Y/18.39R/4.2B/0.1N, peroxide value, 0.7 and bright green color's soybean oil. Sample 3 had acid value, 0.072, Lovibond color, 37.3Y/3.8R/0.1B/0.1N, peroxide value 1.6 and dark brown color's soybean oil. These colorful DSO were expects as raw-materials of various seasoning oils as like pine needle and/or perilla leaf seasoning oil.

• Food Science and Preservation
• /
• v.11 no.4
• /
• pp.448-454
• /
• 2004

This study was conducted to analyze the cooling and the quality characteristics of milled rice stored in the forced air-blast type using thermo -electric semiconductor and in the still-air type chambers using refrigeration system with refrigerant(R-22). Cooling rates of milled rice in the forced air-blast type and in the still-air type chambers were $0.30\;^{\circ}C/hour$ and $0.21\;^{\circ}C/hour$, respectively. And the temperatures of cooling air and of milled rice at different positions in the forced air-blast type chamber showed severer change than those in the still-air type chamber. During storage of milled rice in the forced air-blast type and still-air type chambers for 14 weeks, there was no significant difference in the quality characteristics, such as b value and fat acidity of milled rice, and overall sensory quality of cooked rice. But the quality characteristics of milled rice stored in room temperature chamber($25^{\circ}C$) as control decreased very rapidly compare to those stored in the cooling chambers. In aspect of fat acidity of milled rice, 6 weeks was the limitation for the safe storage in room temperature.

• Applied Chemistry for Engineering
• /
• v.29 no.6
• /
• pp.746-752
• /
• 2018

In this study, an optimized process for the waste cooking oil based biodiesel production using microwave energy was designed by using Box-Behnken design model. The process variables were chosen as a mole ratio of the methanol to oil, microwave power, and reaction time. Fatty acid methyl ester (FAME) content was then measured. Through the results of basic experiments, the range of optimum operation variables for the Box-Behnken design model, such as the methanol/oil mole ratio and reaction time, were set as between 8 to 10 and between 4 to 6 min, respectively. Ranges of the microwave power were set as from 8 to 12 W/g for 1.30 mg of KOH/g, acid value, while from 10 to 14 W/g for 2.00 mg of KOH/g, acid value. The optimum methanol/oil mole ratio, microwave power, and reaction time were reduced to 7.58, 10.26 W/g, and 5.1 min, respectively, for 1.30 mg KOH/g of acid value. Also, the optimum methanol/oil mole ratio, microwave power, and reaction time were 7.78, 12.18 W/g, and 5.1 min, respectively, for 2.00 mg KOH/g of acid value. Predicted FAME contents were 98.4% and 96.3%, with error rates of less than 0.3%. Therefore, when the optimized process of biodiesel production using microwave energy was applied to the Box-Behnken design model, the low error rate could be obtained.

• Journal of Adhesion and Interface
• /
• v.24 no.3
• /
• pp.77-85
• /
• 2023

In this research, polymeric anionic surfactants having various molecular weights and acid values were synthesized using a continuous stirred tank reactor (CSTR). The CSTR has an advantage of higher production rate and more constant product properties compared to batch and semi-batch reactors. The polymeric surfactants were made using butyl acrylate as a hydrophobic group and acrylic acid as a hydrophilic group. The synthesized polymeric surfactants were ionized with alkali solution and were used as an anionic surfactant. To investigate the properties as a surfactant, the properties of the synthesized surfactant, such as acid value, critical micelle concentration (CMC) and molecular weight, were measured. The results showed that the acid values of the polymeric surfactants were 60 to 380 and a number average molecular weight were 8,000 to 13,000 g/mol. Also, it was found that the CMC was around 0.01 g/ml, which showed similar level values with ordinary surfactant. To prove the performance of the polymeric surfactant, acrylic emulsion PSAs were synthesized using the acquired polymeric surfactant. The results showed that the maximum peel strength of 21.24 N/25mm when acid value was 150 and molecular weight was 8,500 g/mol. The values of peel strength and initial tack of acrylic emulsion PSAs using polymeric surfactant synthesized in this study showed much higher than those of reference PSAs synthesized using ordinary anionic surfactant, SDS (Sodium Dodecyl Sulfate) and SDS/TRX (Triton X-100).

• Journal of Food Hygiene and Safety
• /
• v.39 no.2
• /
• pp.83-94
• /
• 2024

The proportion of plant-based meat alternative (PBMA) consumers has recently increased in Korea. This is due to several reasons including protecting the environment, satisfying preferences, maintaining health, and improving eating habits. Accordingly, many companies produce and sell alternative meat using various materials. Alternative meats are classified into plant (such as soybeans and wheat), seaweed, insect, and cultured meats, depending on the raw materials used in manufacturing. PBMA is sold after undergoing processes such as grinding, seasoning, and molding. Therefore, monitoring the presence of any hazardous elements during this process is essential. Accordingly, in this study, we analyzed the harmful components of nine domestically distributed PBMA that are most easily accessible to consumers. After extracting fat from the samples and analyzing the rancidity level, samples F, G, and I were highly rancid. Trace amounts of aflatoxin were detected in samples A and B, but confirmed to be within the range. Cd and Pb were not detected in any sample. We hope that this study will help establish methods to ensure the safety of domestically sold PBMA.