• Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.189-195
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• 2014

Headspace volatile compounds of cold-stored and freeze-dried Krill Eupausia superba were analyzed to investigate their flavor qualities using a system combining a dynamic headspace isolator, an automatic thermal desorber, and a gas chromatograph-mass-selective detector. Levels of oxidation products of polyunsaturated fatty acids such as aldehydes, alcohols, and ketones, which are known to give seafood a nasty smell because of their low flavor threshold values, increased during cold storage of krill. Notably, levels of 2-methylpropanal, 3-methylbutanal, 2-methylbutanal and 2-butanone increased during its storage. They can be considered index compounds of off-odor according to freshness degradation during storage. By contrast, in freeze-dried krill powder, levels of aldehydes, ketones, and aromatic compounds decreased rapidly. Only alcohols, which did not greatly affect the food flavor, were isolated in large amounts. It was confirmed that levels of oxidized compounds of krill increased during cold storage, but decreased in freeze-dried krill.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.15 no.1
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• pp.99-111
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• 2004

Both baked sausage with freeze-dried Kimchi powder(FDKP) and unbaked sausage with FDKP were compared for the analysis. The results are as follows. First, general scores for baked sausage FDKP were higher than those of unbaked sausage with FDKP. Second, baked sausage with freeze-dried Kimchi powder showed scores in color(7.15), taste(7.10), softness(6.00), and overall(7.15) for 3% FKP preference the most. Third, unbaked sausage with FDKP showed scores in color(6.65) for 9% FDKP preference the most. Color is preferred with both 3%(6.45) and 6%(6.45) FDKP. Fourth, softness(5.70) is preferred with the control group. Fifth, taste(6.45), overall(6.25), and hotness(6.85) were preferred with 3% FDKP. Therefore, baked and unbaked sausages with 3-6% FDKP were judged the most commodities.

• Food Engineering Progress
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• v.13 no.3
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• pp.216-220
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• 2009

The several functional properties of freeze-dried powder of Aloe vera gel was examined as influenced by pre-concentration degrees of the gel solution. As a pre-treatment prior to freeze drying, the gel solution was vacuum-concentrated by three levels (unit: g-water/g-solids) - high (H), 76; medium (M), 119; low (L), 159. In FT-IR spectra, the sample H showed the highest absorbance in the range of 1600-1550 $cm^{-1}$ and 1450-1400 $cm^{-1}$, which corresponded to level of the acetyl group in glucomannan. The sample H of freeze-dried powder was the highest in polysaccharide content, jack bean urease inhibition rate, and FAC (fat adsorption capacity). It could be inferred that the sample H had an effect on Helicobacter pylori inhibition and fat adsorption suppression according to urease inhibition rate and FAC, respectively.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1337-1344
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• 1999

Lactic acid bacteria fermented foods were prepared from egg white powder, casein and growth stimulating agent. pH change and growth of Lactbacillus acidophilus(KCTC 2182) during freeze drying were studied. The effects of freeze drying on sensory evaluation. hardness and volatile aroma compounds in freeze dried sample or reconstituted sample were also studied. Freezing and freeze drying did not affect pH of fermented samples. Number of viable cells in original fermented samples was markedly reduced during freezing or freeze drying. When number of viable cells in original fermented sampler was considered at 100%. survival ratio of viable cells after freezing was $72.0{\sim}82.4%$ and that after freeze dying $10.0{\sim}20.4%$. When sensory properties of original fermented samples were compared with those of freeze dried/reconstituted samples, sensory properties of original samples were generally better than those of freeze dried/reconstitute samples. However, the reconstitution property and the acceptability of freeze dried samples were good. Volatile aroma compounds in original fermented samples were reduced during freeze drying. The reduction degree of volatile aroma compounds varied with sample.

• Nutrition Research and Practice
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• v.2 no.3
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• pp.158-164
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• 2008

This study investigated that the antioxidative effect of freeze-dried cranberry powder against protein and lipid oxidation and ameliorative effect of serum lipid profile in rat fed atherogenic diet. Six weeks old male Sprague-Dawley rats were divided into the following four groups: normal diet group with 5% com oil(control), atherogenic diet group with 5% com oil, 10% lard, 1% cholesterol, and 0.5% sodium cholate(HFC), atherogenic plus 2% cranberry powder diet group(HFC+C2), and atherogenic plus 5% cranberry powder diet group(HFC+C5), and respective diet and water were fed daily for 6 weeks. After the experimental period, the serum lipid profile, such as total cholesterol, HDL-cholesterol, LDL-cholesterol, and triglyceride, ferric reducing ability of plasma(FRAP), plasma phenolics content, superoxide dismutase(SOD) activity, serum protein carbonyl and thiobarbituric acid reactive substances(TBARS) levels were examined. Total phenolic compound and total flavonoid levels in freeze-dried cranberry powder were 9.94 mg/g and 8.12 mg/g, respectively. Serum total cholesterol and LDL-cholesterol levels were not significantly different for cranberry powder treatment, but serum HDL-cholesterol level was significantly increased in HFC+C5 group compared with HFC group. Plasma FRAP value tended to be increased by cranberry powder treatment though there was no significant difference. Plasma total phenol concentrations and SOD activities were not significantly different among all groups. Serum protein carbonyl and TBARS levels were significantly decreased in HFC+C5 group compared with HFC group. Overall results suggested that freeze-dried cranberry powder might have the serum lipid improving effect, as well as anti oxidative effect demonstrated by its protective effect against protein and lipid oxidation.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.2
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• pp.89-96
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• 2017

Various health promoting effects of steamed and freeze-dried mature silkworm powder (SMSP) have been reported. However, it is not still clear which substances in SMSP are responsible for those health promoting effects yet. In this study, we examined and compared the quantities of phytochemicals in SMSP and freeze-dried mulberry leave powder (FMLP). To investigate the optimal solvent for extracting phytochemicals from SMSP and FMLP, we used four different solvents. Among them, 80% ethanol extracts from SMSP and FMLP contained the highest amount of five flavonoids examined. In addition, FMLP had high contents of flavonoids compared with those of SMSP. The amounts of rutin, isoquercetin, astragalin, quercetin, and kaempferol in FMLP were $5.078{\pm}0.187mg/g$, $5.162{\pm}0.083mg/g$, $2.989{\pm}0.061mg/g$, $3.317{\pm}0.236mg/g$, and $2.243{\pm}0.237mg/g$, respectively, while the amounts of rutin, isoquercetin, astragalin, quercetin, and kaempferol in SMSP were $0.171{\pm}0.024mg/g$, $0.252{\pm}0.032mg/g$, $0.374{\pm}0.031mg/g$, $0.645{\pm}0.063mg/g$, and $0.0512{\pm}0.047mg/g$, respectively. Taken together, SMSP could be a source for providing various and readily absorbable flavonoids.

• Korean journal of food and cookery science
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• v.26 no.6
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• pp.831-839
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• 2010

The results of wet noodles added with 0, 1, 3, 5, and 7% freeze-dried maesangi powder demonstrate that the addition of maesangi powder up to 5% was desirable formation of noodles. The moisture contents of wet noodle 35.48~36.42%. As the added amount of maesangi powder increased, weight, volume, water absorption, and turbidity the wet noodle soup after cooking increased. Measurement of color changes between before and after cooking the wet noodles found that as the added amount of maesangi powder increased, the lightness and yellowness increased. Measurement of texture after boiling found that, hardness, chewiness and gumminess tended to increase as the amount of added maesangi powder increased whereas, springiness and cohesiveness were significantly different between the different samples. The results of the sensory evaluation showed that the 3%-added group was the best for color, flavor, and taste while the control groups had the best texture. For overall acceptability, the 3%-added group showed found the highest preference level. Measurement of the changes in total viable cells during storage at $5^{\circ}C$ for 18 days found that 6-days was the optimal storage period for the noodles from the control groups and added groups. As the storing period increased, the maesangi powder added groups showed slower propagation speed for viable cells compared to the control groups.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.805-810
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• 2002

Development of tenderizer using domestic fruits was studied. Kiwifruit was dried using various methods, and the quality of kiwifruit powder was observed during 12 week storage. Frozen kiwifruit was prepared in paste, dice, and whole flesh. After drying, paste-type kiwifruit showed 2.0 and 1.3 times higher proteolytic activity than dice and whole flesh kiwifruits, respectively. Nine hour of hot-air drying or 46 h of freeze-drying eliminated more than 90% of water from kiwifruit, during which discoloring of kiwifruit occurred. Freeze-dried powder showed 6.6 times higher yield and proteolytic activity, and resulted in almost no discolorization than those of air-dried powder. Addition of bulking agent affected the quality of hot air-dried kiwifruit powder, except color, resulting in $3.2{\sim}3.6$ times higher proteolytic activity than that without bulking agent, which is comparable to 60% of the initial freeze-dried powder content. Moisture content of kiwifruit powder with bulking agent sustained consistently during 12 week storage, whereas proteolytic activity decreased for the first 4 weeks. Freeze-drying is a preferable method to produce kiwifruit powder for tenderizer, although hot air-drying with bulking agent treatment is more economical.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.496-505
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• 2023

This study explored a method to enhance the drying process usability of local mangoes by producing foam-mat dried powder under varying drying temperatures (50, 60, 70℃) and foam thicknesses (3, 6, 9 mm). The drying process period ranged from 60 to 390 minutes based on the set conditions, with higher temperatures and thinner foams accelerating drying. Powder chromaticity (L^*,(L^*, a^*, and b^*) demonstrated a declining trend with increasing drying temperature and foam thickness, exhibiting notable variance in chroma values. The water absorption index varied significantly, between 3.08 to 4.24, under different drying conditions, although the water solubility index remained consistent across foam-dried samples. Powder moisture content ranged from 2.53% to 3.83%, with hygroscopicity escalating with temperature and foam thickness. Vitamin C structure was compromised during the hot air drying process, especially at temperatures above 60℃. Electronic nose analysis distinguished foam-dried powder from freeze-dried powder; however, a thicker foam yielded a scent profile closer to that of freeze-dried powder. The findings provide fundamental data on mango foam drying, which is expected to improve processing and storage tech for local mangoes.

• Journal of Apiculture
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• v.34 no.2
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• pp.161-167
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• 2019

There is an urgent need for novel protein sources as an alternative to meat production. Insects, such as honeybees, hold potential as a safe, nutritious and reliable protein source for the future. In the present study, we established optimal powder preprocessing conditions of drone pupae (Apis mellifera L.) for use as a novel food. The content of moisture, crude protein, crude fat, crude ash, carbohydrate and crude fiber in drone pupae(Apis mellifera L.) were analyzed. The crude protein content ranged from 48.5 to 51.8% was found in both freeze-dried and hot-air powdered drone pupae. However, the protein content in the freeze-dried powder was higher than that in the hot-air powder by 3.3%. According to the Korean Food Standard Codex test method, coliforms, Salmonella spp. Staphylcoccus aureus, and Enterohamorrhagice Escherichia coli were not detected in both freeze-dried and hot-air powder. Therefore, we suggest that the high protein content of the powdered drone pupae prepared in this study can serve as a novel food.