• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.50-58
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• 2018

Elephant garlic (Allium ampeloprasum var. ampeloprasum), which belongs to the Alliaceae family along with onion and garlic, has a flavor and shape similar to those of normal garlic but is not true garlic. Additionally, its properties are largely unknown, and its processing and product development have not been reported. In this study, we focused on using elephant garlic to produce a new type of vinegar, for which the market is rapidly growing because of its health benefits. First, we evaluated the effects of elephant garlic addition on acetic acid fermentation of rice wine by Acetobacter pasteurianus. In contrast to normal garlic, for which 2% (w/v) addition completely halted fermentation, addition of elephant garlic enabled slow but successful fermentation of ethanol to acetic acid. Metabolite analysis suggested that sulfur-containing volatile compounds were less abundant in elephant garlic than in normal garlic; these volatile compounds may be responsible for inhibiting acetic acid fermentation. After acetic acid fermentation, vinegar with elephant garlic did not have any sulfur-containing volatile compounds, which could positively contribute to the vinegar flavor. Moreover, the amino acid profile of the vinegar suggested that nutritional and sensory properties were more enhanced following addition of elephant garlic. Thus, elephant garlic may have applications in the development of a new vinegar product with improved flavor and quality and potential health benefits.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.372-378
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• 2003

The volatile components of cinnamon bark were extracted by using different isolation methods, simultaneous distillation extraction (SDE) and solid phase microextraction (SPME). Then the volatile components were analyzed by gas chromatography(GC) and mass selective detector(MSD). 30 compounds were identified in cinnamon bark. In SPME technique, several factors influencing the equilibrium of the aroma compounds between sample and SPME fiber was taken into account, including the kind of SPME fiber, extraction temperature and extraction time. Four different SPME fibers were tested, namely polydimethylsiloxane (PDMS), poly acrylate(PA), divinyl- benzene-carboxen-polydimethylsiloxane (DVB/CAR/PDMS) and carbowax/divinylbenzene(CW/DVB). Among these SPME fiber, PDMS coating fiber showed the best results. The profile of volatile compounds of cinnamon bark at different extraction temperature and extraction time were investigated by 100$\mu\textrm{m}$ PDMS fiber.

• Animal Bioscience
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• v.35 no.7
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• pp.1080-1090
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• 2022

Objective: This study aimed to characterize the effect of pre-treated black garlic (BG) extracts addition into retorted Korean ginseng chicken soup (Samgyetang) on the fatty acid composition and flavour-related indexes. Methods: Four different treatments; Samgyetang made with a 5% (w/w) addition of garlic (G), fresh BG (FBG), oven-dried BG (DBG), or encapsulated BG (EBG) extracts were developed and compared to negative control (NC) without any extract addition. Prepared samples were cooked via retorting at 121.1℃, 1.5 kgf/cm² for 1 h. Results: The BG treated samples were higher in C18:3n3 and C18:2n6 fatty acids, with thrombogenic index was 18% to 20% lower than the NC. EBG yielded the highest umami-related nucleotides (5'-guanosine monophosphate and 5'-inosine monophosphate) and modified some free amino acid (alyne, phenylalanine and leucine) thus possessed the highest equivalent umami concentration among samples. Some individual aldehydes (pentanal, hexanal, and heptanal) were lower, while furans and volatile sulfur compounds were higher than the NC and G treatment group, indicating a potential suppression of unpleasant flavour alongwith the intensificiation of favourable flavour from the addition of BG extracts into retorted Samgyetang. Conclusion: Taken together, the synergistic results of this study indicate that incorportating suitable pre-treatment of BG extract could be of critical importance for the development of the retorted Samgyetang with improved flavour and functionalities.

• Journal of Life Science
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• v.17 no.2 s.82
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• pp.286-292
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• 2007

Free amino acids and volatile compounds of fresh garlic and its liqueur were investigated to search elution profile of those components as basic data for development of garlic liqueur. The garlic was soaked in 20% alcohol solution and then sampled every week for 5 weeks. The major free amino acids were L-aspartic acid, L-glutamic acid, L-arginine, L-alanine, L-proline, L-asparagine and L-serine. Neutral amino acids such as L-threonine, L-proline, L-valine and L-leucine, and aromatic amino acids such as tyrosine and phenylalanine were eluted over 80% of those content in fresh garlic after 3 weeks of soaking, but acidic, basic and sulfur containing amino acids were below 80% even after 5 weeks. Sulfide compounds such as diallyl trisulfide, diallyl disulfide, methyl allyl disulfide, 2-vinyl-4H-1,3-dithi in, 3-vinyl-3,4-dihydro-1,2-dithiin, 3,5-diethyl-1,24-trithiolane, isobutyl isothiocyanate and diallyl sulfide were identified as major volatile compounds of fresh garlic by using GC/MS. Among volatile compounds of fresh garlic, allyl alcohol, diallyl disulfide, 3,5-diethyl-1,2,4-trithiolane, diallyl trisulfide and 3,4-dimethoxy furan were eluted to liqueur, but those compounds except 3,5-diethyl-1,2,4-trithiolane were lowered in liqueur during soaking. Furfural, 5-methylfurfural, 5-hydroxymethylfurfural, dimethyl pyrazine, furfuryl alcohol, 3-hydroxy-2-bytanone and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyr-an-4-one were generated newly and their content increased in liqueur during soaking.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.717-722
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• 2005

Formation mechanisms of light-induced volatile compounds were studied using riboflavin-photosensitized oleic acid model systems. Volatile compounds in model systems with 4000 ppm riboflavin at $35^{\circ}C$ under light or in the dark for 39 hr were isolated and identified by a combination of solid phase microextraction (SPME), gas chromatography (GC), and mass spectrometry (MS). Total volatiles in oleic acid with riboflavin under light for 13, 26, and 39 hr increased by 90, 190, and 270%, respectively, compared to those in oleic acid without riboflavin under light. Total volatiles in samples without riboflavin under light or samples with riboflavin in the dark were not significant in tested conditions (p>10.05). Riboflavin did not act as a photosensitizer when it was dispersed in oleic acid. Heptane, octane, heptanal, octanal, nonanal, and 2-nonenal were significantly increased in riboflavin-photosensitized samples compared to those in samples without riboflavin (p<0,05). Light-induced volatile compounds including heptanal and 2-nonenal from oleic acid could be explained using singlet oxygen oxidation, the formation mechanism of which were not understood using triplet oxygen oxidation. These results will help to understand volatile formation in oleic acid containing foods stored under light.

• Journal of Microbiology and Biotechnology
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• v.34 no.8
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• pp.1653-1659
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• 2024

Starter cultures used during the fermentation of malt wort can increase the sensory characteristics of the resulting beverages. This study aimed to explore the aroma composition and flavor recognition of malt wort beverages fermented with lactic acid bacteria (Levilactobacillus brevis WiKim0194) isolated from kimchi, using metabolomic profiling and electronic tongue and nose technologies. Four sugars and five organic acids were detected using high-performance liquid chromatography, with maltose and lactic acid present in the highest amounts. Additionally, e-tongue measurements showed a significant increase in the sourness (AHS), sweetness (ANS), and umami (NMS) sensors, whereas bitterness (SCS) significantly decreased. Furthermore, 20 key aroma compounds were identified using gas chromatography-mass spectrometry and 15 key aroma flavors were detected using an electronic nose. Vanillin, citronellol, and β-damascenone exhibited significant differences in the flavor profile of the beverage fermented by WiKim0194, which correlated with floral, fruity, and sweet notes. Therefore, we suggest that an appropriate starter culture can improve sensory characteristics and predict flavor development in malt wort beverages.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.1
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• pp.148-156
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• 2020

Objective: This study aimed to evaluate the effect of dietary integration with extruded linseed (EL) on fatty acid (FA) and aromatic profile of goat cheese after 60 (T₆₀) days of ripening. Methods: Thirty goats were divided in two groups. The control group (CG) was fed with conventional diet, whereas the experimental group (EL+) was fed with conventional diet supplemented with 10% of EL. Milk samples were collected on 30 and 60 days of trial to determinate chemical-nutritional composition and FA profile. At the end of experiment, six cheese-making sessions (3 for each group) were carried out using a pooled milk sample obtained from the 15 goats of each group. At 60 days of ripening, cheeses were analyzed for chemical-nutritional composition, FA and aromatic profile. Results: An increase in the milk production, protein, fat and lactose were evidenced in the EL+ goats. Conversely, a reduction of somatic cells was observed in the EL+ compared with the CG. However, no variation was observed for urea and casein levels content in milk samples, and no changes in protein and lipid content were found for cheeses in the two experimental groups. Dietary supplementation with EL modified the FA profile of milk. There was a decrease in saturated FAs and an increase in polyunsaturated FAs. Chemical composition of T₆₀ cheese did not differ between the two groups but a different FA profile was observed. In T₆₀ cheese obtained from EL+ milk, an increase in short-chain FA and a decrease in medium and long-chain FA were observed. The EL diet led to cheeses with butanoic acid 2 times higher compared to CG cheeses. Moreover, a greater presence of aldehyde compounds and alcohols were observed in the cheeses of experimental group. Conclusion: The present study pointed out that EL supplementation may improve the chemical and physical qualities of goat milk and cheeses.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.8
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• pp.1116-1122
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• 2015

This study aimed to investigate the effect of sunflower seeds, either as whole or as oil, on rumen fermentation, milk production, milk composition and fatty acids profile in dairy goats. Fifteen lactating Damascus goats were divided randomly into three groups (n = 5) fed a basal diet of concentrate feed mixture and fresh Trifolium alexandrinum at 50:50 on dry matter basis (Control) in addition to 50 g/head/d sunflower seeds whole (SS) or 20 mL/head/d sunflower seeds oil (SO) in a complete randomized design. Milk was sampled every two weeks during 90 days of experimental period for chemical analysis and rumen was sampled at 30, 60, and 90 days of the experiment for ruminal pH, volatile fatty acids (tVFA), and ammonia-N determination. Addition of SO decreased (p = 0.017) ruminal pH, whereas SO and SS increased tVFA (p<0.001) and acetate (p = 0.034) concentrations. Serum glucose increased (p = 0.013) in SO and SS goats vs Control. The SO and SS treated goats had improved milk yield (p = 0.007) and milk fat content (p = 0.002). Moreover, SO increased milk lactose content (p = 0.048) and feed efficiency (p = 0.046) compared to Control. Both of SS and SO increased (p<0.05) milk unsaturated fatty acids content specially conjugated linolenic acid (CLA) vs Control. Addition of SS and SO increased (p = 0. 021) C18:3N3 fatty acid compared to Control diet. Data suggested that addition of either SS or SO to lactating goats ration had beneficial effects on milk yield and milk composition with enhancing milk content of healthy fatty acids (CLA and omega 3), without detrimental effects on animal performance.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.374-379
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• 2003

Four rumen fistulated Murrah buffaloes were used to study the effect of four diets differing in roughage to concentrate ratio on rumen biochemical changes, microbial enzyme profile and in sacco degradability of feed in a $4{\times}4$ Latin Square design. The animals were fed four diets consisting of 80:20, 70:30, 60:40 and 50:50 ratios of wheat straw and concentrate mixtures, respectively. Wheat straw and concentrate mixture were mixed with water (0.6 l/kg feed) and complete feed mixture was offered to the animals at 8:00 h and 16:00 h in two equal parts. The variation in pH of rumen liquor (difference of maximum and minimum during 0-8 h post feeding) increased with increasing level of concentrate mixture in the diet. There was no effect of diet composition on volatile fatty acids, total nitrogen and trichloro-acetic acid precipitable nitrogen in the rumen liquor, but ammonia nitrogen increased with increasing level of concentrate mixture in the ration. Major portions of all fibre degrading enzymes were present in the particulate material (PM) of the rumen contents, but protease was absent in PM fraction. The activities of micro-crystalline cellulase, acetyl esterase and protease increased with increase in the level of concentrate mixture, but the activities of other enzymes (carboxymethylcellulase, filter paper degrading activity, xylanase, $\beta$-glucosidase and $\beta$-xylosidase) were not affected. The in sacco degradability and effective degradability of feeds increased with increasing level of concentrate mixture in the ration.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1294-1296
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• 1998

Platinum thin films which hardly form volatile compounds with any reactive gas at normal process temperature was etched in Inductively Coupled Plasma (ICP) using Ar/HBr/$Cl_2$ gases. It is observed that the etch rate of platinum is reduced as increasing of HBr/$Cl_2$ gas mixing ratio when Ar gas ratio is fixed. However, we obtain good etching profile of platinum films without unwanted residues in 90% Ar/5% HBr/5% $Cl_2$ gas mixing ratio.