• Food Science and Biotechnology
• /
• v.18 no.4
• /
• pp.932-938
• /
• 2009

Browning of tea infusion is an obstructive factor influencing shelf life of ready-to-drink green tea. Effects of temperature and illumination on the browning of green tea infusion were investigated. It was shown that both elevated temperature and illumination led to the browning of green tea infusion, but temperature had greater effect on infusion color and level of catechins than illumination. The levels of unoxidized catechins such as (-)-epigallocatechin gallate (EGCg), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), (-)-epicatechin (EC), and total catechins remaining in the tea infusion were significantly correlated to color parameters of the tea infusion. Sodium ascorbate inhibited the infusion browning by suppressing the oxidation of tea catechins and it is considered to be a more suitable preservative for prolonging shelf life of ready-to-drink green tea than ascorbic acid because it has less effect on tea taste. The effects of temperature and illumination on the epimerization of catechins were also discussed.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.29 no.2
• /
• pp.218-223
• /
• 2000

The objective of this study was to investigate the effectiveness of preservatives for extending storage life and maintaining the quality of minimally processed Chinese cabbage. Cut Chinese cabbage was treated with either 1% CaCl2, 1% NaCl, 3% sucrose, 1% Ca-lactate, 1% vitamin C, 0.05% chitosan＋1% vitamin C, 0.1% Sporix＋1% vitamin C or hot water(6$0^{\circ}C$) and then packed with polyethylene film(60${\mu}{\textrm}{m}$) and stored at either 2$0^{\circ}C$ or 4$^{\circ}C$. To evaluate biochemical changes and quality of minimally processed Chinese cabbage, the samples were tested to determine the amount of vitamen C, titratable acidity, organic acid and fiber contents. Changes in color were also examined. The quality of kimchi prepared form minimally processed cabbage was affected by the treatments. REsults indicate that the minimally processed Chinese cabbage treated with either 1% CaCl2 at 2$0^{\circ}C$ and 4$^{\circ}C$ or 1% NaCl at 2$0^{\circ}C$ minimized biochemical changes in plant tissue and those treatments were most effective in maintaining product quality. The cabbage treated with 1% vitamin C or 1% NaCl at 4$^{\circ}C$ resulted in kimchi with improved color, texture, flavor and the best overall acceptability, as determined by a sensory test.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.5
• /
• pp.997-1002
• /
• 1999

The aim of the present study was to investigate effects of food preservative addition and changes in composition of herb extract product on the growth of spoilage yeast, Zygosaccharomyces sp. Herbs such as Panax ginseng, Cinnamomum cassia, Lycium chinense, Zyzyphus juiuba and Jingiber officinale were altogether put into water and essence was extracted at 80oC, and then the extract was concentrated at 75oC. The herb extract product was made by adding vitamins, amino acids and honey to the concentrated herb extract. The amount of gas produced from the herb extract product was increased as inoculated cell number increased but decreased as Brix concentration increased. Gases were produced in small amount when incubation was made at 4oC but large amounts of gases were produced at 25 or 40oC of incubation. The gas production and growth of Zygosaccharomyces sp. were measured after browning reaction was induced by heating at 85oC for 12 hours. It appeared that heating treatment did not induce any significant change in the gas production and growth of the cell. The effects of addition of various sugar to the herb extract produce were also invesigated. Amounts of gas production were in the order of glucose>sucrose>oligosaccharide>stevioside. The viable cell count was measured as 6.0$\times$107 CFU/g when glucose was added to the herb extract product. The viable cell counts were 5.0$\times$106, 3.0$\times$103, and 3.0$\times$102 CFU/g in sucrose, oligosaccharide and stevioside added herb extract product, respectively. The amount of gas production from the herb extract product was remarkably reduced by addition of such food preservatives as sodium benzoate and DF 100. TLC(thin layer chromatography) chromatogram of the herb extract showed stability of the herb extract in the above treatments.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.2 no.1
• /
• pp.49-54
• /
• 1973

In this paper, the effect of Ever-Fresh, a kind of preservatives for fish and shellfish, on fish and shrimp during ice storage were investigated. The results are as follows: 1. K value representing the ratio of optical densities of inosine and hypoxanthine fraction and total nucleotide fraction at 250nm could be useful as an index to measure the freshness of fish and shrimp during ice storage. 2. Volatile basic nitrogen could be also useful as an index to measure the freshness of shrimp during ice storage. 3. Ever-Fresh treatment of conger eel, half-beak, and shrimp appeared effective on keeping freshness during the early stage of ice storage. 4. Ever-Fresh treated shrimp showed lower thiobarbituric acid value as compared with the control during the early stage of ice storage.

• Korean Journal of Food Science and Technology
• /
• v.35 no.5
• /
• pp.825-829
• /
• 2003

An electronic nose was applied to analyze the aroma patterns of powdered red ginseng that had been treated with different preservative methods, such as gamma radiation at 5kGy, commercial methyl bromide (MeBr) and phosphine fumigations. Aroma patterns of phosphine or MeBr, fumigated samples were well separated according to storage temperature and period. However, 5kGy-irradiated samples (stored for 1 and 2 months) were hardly discriminated by the different storage temperatures ($25^{\circ}C$ and $-10^{\circ}C$). After 5 months at $-10^{\circ}C$, non-treated and phosphine fumigated samples showed similar aroma patterns.

• Food Science of Animal Resources
• /
• v.39 no.6
• /
• pp.918-933
• /
• 2019

Cacao has been shown to have antioxidant effects and health benefits. However, the applicability of cacao as a meat preservative has not been thoroughly evaluated. Here, we examined the effects of cacao nib extracts (CEs) on suppression of fat oxidation and enhancement of quality characteristics of pork patties. Cacao nib powder was extracted in distilled water or 50%, 70%, or 99% ethanol. CEs prepared using 70% ethanol had the highest total phenolic and total flavonoid contents, and the highest 1,1-diphenyl-2-picrylhytdrazyl radical and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities. Decompression-concentrated CEs prepared using 70% ethanol and 0.1% ascorbic acid were added to pork patties, and the physiochemical properties of the patties were measured. The pH of all pork patties increased during storage, but tended to decrease according to the CEs content. CEs enhanced the preservation of redness and texture of the pork patties during storage. Analysis of thiobarbituric acid reactive substances (TBARS) in patties revealed that fat oxidation was highly suppressed in all treatment groups containing CEs during storage, and TBARS values decreased according to CE content. Treatment with 0.1% CE reduced fat oxidation to a level similar to that of treatment with 0.1% ascorbic acid. Consumer flavor preference increased according to CE content, and overall preference was the highest for patties prepared with 0.05% and 0.075% CEs. Overall, 70% ethanol was found to be the optimal concentration for extraction of cacao nibs, and adding 0.05% or 0.075% CEs to pork patties yielded the highest quality.

• Korean Journal of Food Science and Technology
• /
• v.34 no.4
• /
• pp.746-749
• /
• 2002

From 7 different medicinal herbs, Rubus coreanus miquel, Therminalia chebula Retz and Rhus javanica was selected by paper disk method against 10 different microorganisms. The ethanol extracts of selected herbs was added into Tofu, and the total viable cell counts was determined. After 4 days, total viable cell count reached to $10^7$ and the Tofu putrefacted. The tested sample added with 0.01% of Terminalia Chebula Retz extract, the shelf-life was extended as 108.8%, with 0.05% was 117.3% and with 0.1% was 132.6%. Among 3 kinds of medicinal herb, Therminalia chebula Retz has better powerful activity than others.

• Food Science and Preservation
• /
• v.19 no.6
• /
• pp.919-924
• /
• 2012

This study was conducted to investigate the antimicrobial activities and antioxidant activities of the Korean mistletoe extract and its solvent fractions (e.g. n-hexane, ethyl ether, ethyl acetate, butanol). Ethyl ether fraction against Bacillus cereus showed stronger activities than benzoic acid (2.5 mg/mL). The MIC of korean mistletoe extract and slovent fractions were in the range of 6.25-25 mg/mL. The MIC (6.25 mg/mL) of ethyl acetate fraction onto Staphylocossus aureus was the lowest among them. Ethyl ether fraction which showed the strongest antioxidant activities by DPPH (1,1-diphenyl-2-picryl-hydrazyl) and FRAP (ferric ion reducing antioxidant power) methods had the highest total phenolic contents. It is suggested that Korean mistletoe could be utilized as natural preservative material through the study of the active compounds from ethyl ether fraction.

• Food Science of Animal Resources
• /
• v.35 no.4
• /
• pp.564-571
• /
• 2015

Grape seeds and pericarp are rich in procyanidins, a class of natural antioxidants and antimicrobials that can provide phytonutrients for healthy eating and extend food shelf life. The objective of this study was to assess the effect of procyanidins as preservatives in pork meat patties for 14 d. Pork patties were treated with 0, 0.1, or 0.3% procyanidin, and meat color, pH, volatile basic nitrogen (VBN), 2-thiobarbituric acid reactive substance (TBARS) values, and microbial populations were determined during storage at 4℃ for 14 d. The color of pork patties treated with procyanidin showed lower lightness and higher redness values than untreated controls, and procyanidin treatment reduced pH values significantly (p<0.05). VBN values decreased significantly (p<0.05) with the 0.3% procyanidin treatment and increased significantly (p<0.05) during storage. TBARS values were markedly lower in procyanidin-treated meat than in the untreated control. In addition, procyanidin suppressed total bacterial colony and Escherichia coli counts significantly (p<0.05) relative to the control samples. Our findings suggest that procyanidin could be used as a food preservative in pork patties due to its natural antioxidation and antimicrobial activities, and that it may contribute to an improved healthy diet.

• Korean Journal of Food Science and Technology
• /
• v.31 no.4
• /
• pp.1109-1114
• /
• 1999

The antifungal activity of ethylenediaminetetraacetic acid (EDTA), an antioxidative food preservative, was investigated against Saccharomyces cerevisiae. At the general condition for antifugal test, EDTA exhibited the minimum inhibitory concentration (MIC) of 200 ${\mu}g/ml$ and the minimum fungicidal concentration (MFC) of 6,400 ${\mu}g/mL$, As seen with the antibacterial activity, the antifungal activity of EDTA was greatly decreased by high inoculum size, acidic medium, and cation ($Ca^{++},\;or\;Mg^{++}$) added to medium. On the other hand, when EDTA was combined with polygodial isolated from natural food spice, they showed strong synergism on the antifungal activity. Further, the diminishing antifungal activity of EDTA by high inoculum size, acidic medium, and cation ($Ca^{++}\;or\;Mg^{++}$) added to medium was considerably improved by the combination with polygodial.