• Food Science and Preservation
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• v.20 no.6
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• pp.784-790
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• 2013

The quality characteristics of Campbell grape juice with different extraction processes (AE; autoclave extraction, HWE: hot water extraction, and EE: enzyme extraction) were investigated. The juice yields of the AE, HWE, and EE juices were 79.8%, 82.3% and 92.6%, respectively. The titratable acidity and soluble solids of the EE juice were significantly higher than those of the other extracts. There was no significant difference in the $L^*$ values of the juices, but the $a^*$ and $b^*$ values of the EE juice were higher than those of the other extracts. The viscosity of the HWE and EE juices was higher than that of the AE juice. The major free sugars in the grape juice were identified as glucose and fructose, and the highest organic acid content was found in the EE juice. The total polyphenol content of the EE juice was 55.7 mg% and was higher than those of the AE and HWE juices, which were 31.3 mg% and 39.5 mg%, respectively. Especially, the anthocyanin content of the EE juice was 22.1 mg%, which was two to four times higher than those of the AE and HWE juices, which were 4.5 mg% and 10.5 mg%, respectively. The EE juice showed the highest antioxidant effect, measured from the DPPH free radical scavenging activity and reducing power. In conclusion, we suggest that the enzyme treatment in the grape extraction was more effective than the autoclave and hot water methods.

• Preventive Nutrition and Food Science
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• v.18 no.2
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• pp.133-138
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• 2013

This study was performed to compare the quality and functionality of broccoli juice as affected by extraction method. Broccoli juice was extracted using method I (NUC Kuvings silent juicer), method II (NUC centrifugal juicer), and method III (NUC mixer), and the quality properties of the broccoli juices were analyzed using three different methods. Additionally, the antioxidative, anticancer, and anti-hyperglycemic activities of broccoli juice prepared by the three different methods were investigated in vitro. The broccoli juice made by method I contained the highest polyphenol and flavonoid contents at 1,226.24 mg/L and 1,018.32 mg/L, respectively. Particularly, broccoli juice prepared by method I showed higher DPPH and ABTS radical scavenging activities than those of the other samples. Additionally, broccoli juice made by method I showed the highest growth inhibitory effects against HeLa, A549, AGS, and HT-29 cancer cells. Broccoli juice prepared by method I had the highest ${\alpha}$-glucosidase inhibitory effects. These results indicate that there are important differences in chemical and functional qualities between juice extraction techniques.

• Food Science and Preservation
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• v.3 no.2
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• pp.131-136
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• 1996

Even though plum is well known as a health food, the available processed food of it is quite limited. Furthermore it is difficult to find an easy processing method for leading to a value added product at farmhouse. This study was investigated to effects of temperature for plum extract juice by osmosis of yellow sugar. The plum was mixed with yellow sugar at equal ratio(w/w) to obtain yellowish extracted plum juice and then located in incubator at 15, 25, 35$^{\circ}C$, respectively. The sugar content of extract was high at the early period but decreased throughout extraction period and it was about 66.1~67.4$^{\circ}$Brix. The color difference was increased yellowish throughout the extract period. The pH of it was decreased throughout extract processing but citric acid content was increased. The speed of extraction during extraction processing was more rapid at 15$^{\circ}C$ than 3$0^{\circ}C$. However sensory evaluation score of taste and flavour was obtained at 15$^{\circ}C$ than 3$0^{\circ}C$, so the prefer temperature for plum extract juice by osmosis of yellowish sugar was 15~2$0^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.276-282
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• 2007

In this study, attempts were made to develop a garlic juice extraction method that would result in minimum changes in quality. Protopectinase and a mutienzyme containing cellulase, pectinesterase, ${\beta}-glucanase$, etc. were applied to garlic residue after first extraction, and the yields of garlic juice and the flavor component changes of the juices were investigated. Enzyme concentrations of 0.04, 0.08, and 0.12% which were based on pulp weight before extraction were added and allowed to hydrolyze for 30, 60, 90 and 120 min,. respectively. Increase in the garlic juice yield was observed according to the amount of enzyme added and the reaction time until reaching a maximum point. When 0.12% protopectinase was applied to the garlic residue for 90 min, the yield increased by 13.8%. Under the same conditions, when multienzyme was applied to the garlic residue, the yield increased by 14.5%, which was considered the maximum. The flavor compounds decreased when compared with the total GC peak area of garlic juice prepared without enzymes(control). The volatile flavor compounds in garlic juice prepared with 0.12% protopectinase for 60 min decreased by 6%. The free sugars profile of the garlic juice prepared with 0.12% protopectinase for 60 min was similar to that of the control. The type of enzyme used did not affect the free amino acid profile of the garlic juice. These results indicate that the optimum conditions for extraction of garlic juice are hydrolyzing the residue with 0.12% protopectinase for 60 min, extracting garlic juice from the hydrolyzed reside, and then combining the extracted juice with the first extraction.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.369-378
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• 2019

This study aimed to compare the quality characteristics of carrot juice based on different extraction methods such as centrifugation, single gear, and twin gear methods. Juice quality was evaluated based on extraction yield, nutritional components, and cloud stability. Twin gear extraction resulted in the highest extraction yield, and the highest mineral content. In addtion, ${\beta}$-carotene level higher than the recommended daily intake was obtained only in the carrot juice prepared using twin gear extraction of 100 g carrots. The minimum particle size was observed in twin gear extraction, followed by single gear extraction and centrifugation method. Therefore, twin gear extraction was selected as the optimal method, and changes in the antioxidant and metabolic activity of carrot juice were investigated using this method. Consequently, the carrot juice showed a higher lipid peroxidation inhibition rate than ${\alpha}$-tocopherol (1 mg/mL), and angiotensin I-converting enzyme (ACE) inhibitory activity was increased upon digestion.

• Journal of Food Hygiene and Safety
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• v.38 no.6
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• pp.517-527
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• 2023

This study aimed to examine the possibility of upcycling extracts of Angelica keiskei and Oenanthe javanica juice by-products through comparing enzyme extraction (EE) and complex extraction (CE) methods to increase the extraction yield and flavor of materials. A higher extraction yield was obtained for free amino acid content with EE and CE for A. keiskei and O. javanica juice by-products, respectively, and a higher extraction efficiency was achieved with juice by-products than with extracts prepared from raw materials before juice production. The content of major amino acids varied depending on the extraction method used. When used according to the characteristics of the extract, their use as a functional material was confirmed along with improvement in the flavor of the food. Consistently high extraction yields for organic acid and sugar levels were obtained with CE in A. keiskei and O. javanica juice by-products. The DPPH radical scavenging ability and TPC were consistently high with CE in A. keiskei and O. javanica juice by-products; the increase in extracted content was likely because of the reaction between the ethanol used for CE and the phenolic compounds. However, because the antioxidant capacity of the juice by-product extracts was somewhat lower than that of the extracts from raw materials before juice production, the amount used should be reviewed. The TFC was found to be higher in extracts obtained with EE than with CE for A. keiskei juice by-products; however, no significant difference was observed between EE and CE in the O. javanica juice by-products. Through this study, the taste compounds and antioxidant properties of extracts obtained from juice by-products produced after the production of A. keiskei and O. javanica green juice were analyzed, and the availability of high value-added materials was confirmed. Based on these research results, expanding specific R&D for practical use should be explored.

• Preventive Nutrition and Food Science
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• v.19 no.2
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• pp.108-114
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• 2014

Four Korean kernel fruit (apple, pear, persimmon, and mandarin orange) juices were obtained by household processing techniques (i.e., blending, juicing). Whole and flesh fractions of each fruit were extracted by a blender or a juicer and then examined for phytochemical content (i.e., organic acids, polyphenol compounds). The antioxidant capacity of each juice was determined by ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. Results revealed that juices that had been prepared by blending whole fruits had stronger antioxidant activities and contained larger amounts of phenolic compounds than juices that had been prepared by juicing the flesh fraction of the fruit. However, the concentration of ascorbic acid in apple, pear, and mandarin orange juices was significantly (P<0.05) higher in juice that had been processed by juicing, rather than blending. The juices with the highest ascorbic acid (233.9 mg/serving), total polyphenols (862.3 mg gallic acid equivalents/serving), and flavonoids (295.1 mg quercetin equivalents/serving) concentrations were blended persimmon juice, blended mandarin orange juice, and juiced apple juice, respectively. These results indicate that juice extraction techniques significantly (P<0.05) influences the phytochemical levels and antioxidant capacity of fruit juices.

• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.890-896
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• 2018

The aim of this study was to determine volatile flavor compounds in Shingo pear juice. Volatile flavor compounds were analyzed using solid-phase micro-extraction (SPME) - gas chromatography-mass spectrometry (GC-MS). The effect of inorganic salts solution on the extraction ability of the SPME fiber was treated by adding saturated $CaCl_2$ solution at the ratio of 1:20 (v/v) after 0, 60, 120 min of preparing pear juice, respectively. As a result, a total of 22 volatile compounds were identified in Shingo pear juice. Ethyl acetate was found to be the most abundant volatile compound ($13.36{\sim}19.61{\mu}g/kg$), followed in order by hexanal, ethyl hexanoate, ethyl 3-(methylthio)-2-propenoate, ethyl octanoate and 2-hexenal. Total contents of volatile flavor compounds were $31.07{\mu}g/kg$ (control), $40.93{\mu}g/kg$ (0 min), $27.62{\mu}g/kg$ (60 min) and $26.32{\mu}g/kg$ (120 min). This result indicated that the addition of saline solutions could inhibit the enzymatic reaction of volatile flavor compounds effectively when treated as soon as juice preparation.

• Journal of Microbiology and Biotechnology
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• v.33 no.4
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• pp.533-542
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• 2023

Exo-polygalacturonase (exo-PG) hydrolyzes pectin acids and liberates mono-galacturonate, which plays an important role in juice extraction, and has rarely been reported. Exo-PG (AfumExoPG28A) from Aspergillus fumigatus belongs to the glycoside hydrolase 28 family. In this study, its gene was cloned and the protein was expressed and secreted in Pichia pastoris with a maximal activity of 4.44 U/ml. The optimal temperature and pH of AfumExoPG28A were 55℃ and 4.0, respectively. The enzyme exhibited activity over almost the entire acidic pH range (>20.0% activity at pH 2.5-6.5) and remained stable at pH 2.5-10.0 for 24 h. The K_m and V_max values of AfumExoPG28A were calculated by the substrate of polygalacturonic acid as 25.4 mg/ml and 23.6 U/mg, respectively. Addition of AfumExoPG28A (0.8 U/mg) increased the light transmittance and juice yield of plantain pulp by 11.7% and 9%, respectively. Combining AfumExoPG28A (0.8 U/mg) with an endo-PG (0.8 U/mg) from our laboratory, the enzymes increased the light transmittance and juice yield of plantain pulp by 45.7% and 10%, respectively. Thus, the enzyme's potential value in juice production was revealed by the remarkable acidic properties and catalytic activity in fruit pulp.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.257-262
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• 2010

Patulin, a secondary metabolite of mold, is commonly found in rotten apples. Many countries regulate patulin at levels ranging from 30 to $50\;{\mu}g/L$. Most analytical methods for removing patulin from apple juice include liquid-liquid extraction (LLE), which is time and labor intensive. To replace the LLE method, a solid-phase extraction (SPE) method has been developed for apple juice and unfiltered apple juice. A portion of the test sample was applied to a macroporous copolymer cartridge and washed with 5 mL of 1% sodium bicarbonate, followed by 5 mL of 1% acetic acid. Patulin was eluted with 5 mL of 2% acetonitrile in anhydrous ethyl ether. The mobile phase was tetrahydrofuran in water (0.8:99.2) and was detected with a UV detector at 276 nm. Recoveries ranged from 95 to 101% in test samples, and the minimum detectable level was 30 ppb. Because this SPE method is fast, easy, reliable, and inexpensive, it could be applicable for companies or analytical agencies to analyze patulin concentrations in apple juice.