Since 2010, the Odor Prevention Act has identified and regulated four types of fatty acids as substances that cause odors. Four types of fatty acids are contributors to odor pollution and are sensitive to changes in temperature and humidity. However, the current analysis method has several limitations, including dependency on the timing of sampling before and after the procedure, as well as dependency on the specific analysis method employed. The aim of this study is to assess the efficacy of the ion chromatography analysis method by utilizing ultrapure distilled water as a means to improve the current approach. Initially, the analysis system underwent a quality assessment. The results indicated a linearity (R2) of 0.99, a limit of 10 nmol/mol or lower, supporting the conclusion that it is suitable. Furthermore, the investigation focused on the substance’s tendency to change over time in ultrapure water and under alkali absorption (0.01N NaOH). At a concentration of 0.95 ng (low-concentration standard sample), the confirmed peak area values ranged from 0.0004 μg/min to 0.0010 μg/min, resulting in an injection variation of approximately ± 0.001. At 23.7 ng (high-concentration standard sample), the peak area value fluctuated between 0.008 μg/min and 0.013 μg/ min, with an average of ± 0.002. Therefore, storing the material at temperatures below 4°C for up to 3 days (72 hours) after manufacturing seemed to facilitate the optimal conditions for maintaining its stability without significant changes taking place. Finally, blank samples from the laboratory, equipment, and site were analyzed. Out of the four substances analyzed, only n-butyl acid was detected in all three background samples. It was confirmed that it represented 4% of the peak area in the 4.94 ng standard sample.

본 연구는 소맥 위주 사료에 xylanase 효소제의 첨가가 육성돈의 사양성적, 영양소 소화율, 혈액성상, 분 중 휘발 성 지방산 및 암모니아성 질소 농도에 미치는 영향을 알 아보기 위하여 실시하였다. 총 192두(4처리, 8반복, 반복당 6두)의 육성돈(25.14±0.11 kg)을 공시하여 xylanase 첨가수 준(0, 0.0125, 0.025, 0.0375%)으로 6주간 사양시험을 실시 하였다. xylanase의 첨가수준이 증가함에 따라 전체 사양 구간에서의 일당증체량(ADG), 일일사료섭취량(ADFI) 및 사료요구율(FCR)이 유의적으로 개선되는 효과를 나타냈 다(p<005). 영양소 소화율에 있어서, xylanase 첨가수준이 증가함에 따라 phase Ⅰ에서는 건물 및 에너지, phase Ⅱ 에서는 조단백질 소화율이 유의적으로 개선되었으며, 또 한 육성돈의 혈중 GLU 농도는 사료 내 xylanase의 첨가 수준이 증가함에 따라 유의적으로 증가하는 효과를 보였 다(p<0.05). 반면에, 휘발성 지방산 및 암모니아성 질소 농 도에서 xylanase의 유의적인 첨가효과는 나타나지 않았다 (p>0.05). 결론적으로, 소맥 위주의 사료 내 xylanase의 첨 가는 육성돈의 사양성적, 영양소 소화율 및 혈중 GLU 농 도를 증가시키는데 긍정적인 효과를 보였으며, 육성돈 사 료내 소맥을 주원료로 사용할 경우 xylanse의 적정 첨가 수준은 0.0375%으로 사료된다.

The sampling bag is used as a storage container for odor gas samples. It is known that the substances recovery rate of odor bags decreases during storage time, and the degree of recovery varies depending on the characteristics of the gas sample and the material of the bag. This study investigated the recovery rate of VFA (ACA, PPA, BTA, VLA) in PEA bags during storage time. In addition, a model was developed to estimate the recovery rate of each substance as a function of time. Standard gas (ACA, PPA, BTA, VLA mixed) recovery rate was used for the model development. The concentration of the compound in the bag was measured by SIFT-MS at intervals of 1 to 2 hours. The recovery rate according to the storage time was calculated as the ratio to the initial concentration. The recovery rate of each substance according to the storage period (12h, 24h, 36h, 48h) was ACA (66.2%, 62.8%, 55.6%, 52.0%), PPA (77.6%, 72.1%, 63.0%, 58.1%, 86.6%), BTA (86.6%, 81.3%, 71.6%, 66.9%), VLA (94.8%, 89.0%, 76.6%, 71.7%). The recovery rate continued to decrease over the course of 48 hours of storage time. ACA, PPA, and BTA showed the greatest decrease within the initial 12 hours, which is form of exponential decrease. Therefore, we considered a 1~3 degree polynomial regression model and a 1~2 degree exponential decay model. Each developed model was evaluated by r², RMSE, MAPE, AIC, and then a model for each substance was selected. Selected models were tested with recovery rate data from swine farm odor samples. Only the ACA model exhibited a good performance (r² = 0.76).

The present study was conducted to determine the optimal supplementation level of beta-mannanase in the diet of laying hens. A total of 320 Hy-Line Brown layers (80 weeks of age) were assigned randomly into four groups on the basis of laying performance. Each treatment had eight replicates with 10 birds each (80 birds per treatment). Two hens were caged individually. Treatments were basal diet supplemented with 0 (control), 0.04, 0.08, and 0.16% beta-mannanase during the nine-week feeding period. Laying hens fed diets supplemented with increasing levels of beta-mannanase had increased (linear, p<0.05) overall egg production and egg mass. In addition, these hens had greater retention of dry matter, crude protein, gross energy, calcium, and mannan (linear, p<0.05). Dietary beta-mannanase treatments had no effect on blood metabolites such as total carbohydrate, triglycerides, glucose, total protein, and blood urea nitrogen, or excreted ammonia nitrogen and volatile fatty acids. The results obtained in present study indicate that dietary supplementation of beta-mannanase has the potential for improving the performance of laying hens. The optimal supplementation level is 0.04% beta-mannanase in the diet.

Acetate, propionate, butyrate are the major soluble volatile fatty acids metabolites of fermented food waste leachates. This work investigate the effects of volatile fatty acid on the growth rate and NH4-N, PO4-P removal efficiency of mixotrophic microalgae Chlorella vulgaris to treat digested food waste leachates. The results showed that acetate, propionate and butyrate were efficiently utilized by Chlorella vulgaris and microalgae growth was higher than control condition. Similar trends were observed upon NH4-N and PO4-P consumption. Volatile fatty acids promoted Chlorella vulgaris growth, and nutrient removal efficiencies were highest when acetate was used, and butyrate and propionate showed second and third. From this work it could be said that using mixotrophic microalgae, in this work Chlorella vulgaris, fermented food waste leachates can be treated with high efficiencies.

비육돈사의 슬러리에 함유된 악취물질의 농도를 계절별로 비교하여 초지 및 농경지에 살포되는 분뇨의 악취강도를 예측하고자 수행되었다. 1.비육돈사의 슬러리에 함유된 휘발성유기물의 계절별 농도 비교페놀류 중 p-크레졸 농도는 봄, 여름 및 가을에 차이가 없었지만, 페놀, 인돌 및 스카톨 농도는 여름과 가을에 비해 봄에 높았다(p<0.05). 돼지 슬러리의 경우 p-크레졸과 스카톨이 악취강도에 큰 영향을 주기 때문에 계절에 따른 휘발성유기물의 악취강도 차이는 크지 않을 것으로 판단된다. 2.비육돈사의 슬러리에 함유된 휘발성지방산의 계절별 농도 비교휘발성지방산의 경우 악취강도가 높지 않은 단쇄지방산의 농도는 봄철이 여름과 가을보다 높았으나(p<0.05), 악취강도가 상대적으로 높은 이성체지방산의 농도는 계절별로 숫자적인 차이는 보였지만 통계적인 차이는 없었다(p> 0.05). 계절에 따라 휘발성지방산이 악취강도에 미치는 영향은 높지 않을 것으로 판단된다. 결과적으로 봄철에 악취물질의 농도가 더 높은 것은 온도, 환기 및 돈사내부로 유입되는 물의 양에 의한 것으로 추정되며, 여름철은 슬러리에서 생성되는 악취농도 보다 환기에 의해 휘산되는 양이 많아서 슬러리의 악취농도가 감소되거나 증가되지 않았을 가능성이 있는 것으로 판단된다. 이상의 연구결과를 종합하면 비육돈사의 슬러리를 초지 또는 농경지에 살포하였을 때 계절에 의한 악취강도의 차이는 크지 않을 것으로 기대된다.

A lab-scale Anaerobic Baffled Reactor (ABR) was applied to treat a primary sludge taken from a municipal wastewater treatment plant. In this experiment, acidogenic reaction was promoted by operating the ABR with short hydraulic retention time (HRT) to produce sufficient volatile fatty acids (VFA) instead of production of methane. The performance of ABR on the VFA production and total solids reduction was observed with different operating conditions with 2, 4, 6, and 8 days of HRT. Corresponding organic loading rates were 6.7, 3.4, 2.2, and 1.6 kgCODcr /m3·day. As HRT increased the removal rate of TCOD was also increased (82.5, 84.2, 96.9, and 95.9 % in average for HRT of 2, 4, 6, and 8 days, respectively) because the settlement of solids was enhanced in the baffle by the decrease of upflow velocity. At HRT of 2 days the average concentration of VFA in the effluent was measured at 1,306±552 mgCOD/L corresponding to 107 % increment as compared to the VFA concentration in the influent. However, as HRT increased VFA concentraiotn was decreased to 143±552 mgCOD/L at HRT of 8 days. The reduction rates of total solids were 12.2, 26.5, 24.8, and 43.0 % for HRT of 2, 4, 6, and 8 days. As HRT increased the hydrolysis of organic particulate matters in the reactor was enhanced due to the increasing of solids retention time in the baffle zone with low upflow velocity in long HRT condition. Consequently, we found that a primary sludge became a good source of VFA production by the application of ABR process with HRT less than 4 days and the 12-26 % of total solids reduction was expected at these conditions.

In this study, alkali impregnated filter sampling method was considered for VFAs in ambient air. When KOH concentration was 0.5 N and sampling flow velocity was 5~10 L/min the sampling efficiency was higher than 90 percent. More than 3 minute shaking make the sampled filter to be suspended in the 22.3 mL Vial. Alkali impregnated filter sampling method showed more than 4 times higher response compared to alkali solution sampling method, when the sample was analysed by headspace-gas chromatography. Five kinds of volatile fatty acids (propionic acid, i-butyric acid, n-butyric acid, i-valeric acid, valeric acid) were detected within 1.0~9.8 ppbv in the cow shed by alkali impregnated filter method and headspace gas chromatography. The alkali impregnated filter method was the most suitable sampling method for ambient volatile fatty acids with headspace gas chromatography analysis.

휘발성 지방산의 생성 및 회수를 위한 분리막의 유효성을 실험적으로 검토한 결과, 분리막의 적용에 의해 발효조 내의 부유고형물 농도, 유기산 생성균수 및 유기산 농도가 증가하였다. 혐기성 발효액의 고액분리 및 발효 효율향상을 위한 분리막의 적용은 발효조 내의 관련 미생물 농도를 증가시키고 따라서 분리막을 적용하지 않은 경우에 비해 유기산 생성효율이 훨씬 증가하였다. 분리막이 결합된 산 발효조의 적용은 유기성 슬러지로부터 휘발성 지방산의 회수 효율증대에 효과적인 적용기술이라 판단된다.

This study aimed to investigate the effect of amino acid additives to weaned piglet diets on the pH and volatile fatty acids of pig slurries. A total of 135 weaned 22 -day-old piglets (Yorkshire x Landrace x Duroc) were used in this 56-d study. The three dietary treatments were as follows: (1) Control as a basal diet, (2) 1% amino acid additive and (3) 2% amino acid additive. Both pH and acetic acid values at 71 and 78 days were significantly different in all treatment groups (p<0.05). In addition, significant differences in propionic acid values were observed among treatment groups at 64 and 78 days (p<0.05). However, pH, acetic acid, and propionic acid values did not differ between 1% and 2% amino acid treatment groups. In conclusion, adding 1% and 2% amino acid to weaned piglet diets reduced the pH, acetic acid and propionic acid contents of pig slurries by acting as a probiotic. This may help formulate increase management strategies for improving the pig housing environment.

지구 온난화와 같은 환경 문제가 대두되고 화석 연료에 대한 의존도가 높아짐에 따라 탄소 중립 개념에 대한 관심이 높아졌다. 특히, 전세계적으로 폐기물의 에너지화에 대한 연구가 활발히 진행되고 있다. 혐기성 소화는 유기성 폐기물로부터 바이오가스를 생성하는 에너지 회수의 한 방법으로써 전 세계적으로 많이 사용되는 기술이며 혐기성 소화의 효율 증대와 관련된 연구 또한 지속되고 있다. 혐기성 소화의 효율 극대화와 안정적인 운영을 위해서는 운영 조건을 최적화하고 최적화된 운영 조건을 모니터링 및 관리하는 것이 매우 중요하다. 혐기성 소화 운영에 있어 메탄가스량, 온도 등과 같은 여러 인자들 중, 휘발성 유기산의 농도 변화를 모니터링하는 것은 단시간에 급작스러운 반응조 내 변화를 확인하는 데에 매우 효과적인 인자 중 하나라는 것이 많은 연구를 통해 밝혀졌다. 기존 휘발성 유기산 농도 측정법에는 적정법, GC분석법 등이 있으며, 이들 측정법들은 분석 시간이 오래걸리고 측정 결과가 분석 조건에 민감하기 때문에 새로운 측정법의 개발이 요구되는 실정이다. 본 연구에서는 이러한 단점을 보완하며 신뢰성이 확보된 결과를 측정할 수 있는 다공성 물질 이용 촉매모사반응을 적용하였다. 본 연구에서 다룬 휘발성 유기산 측정 방법은 다공성 물질을 이용하여 열적 처리를 통한 휘발성 유기산의 에스터화반응을 이용한 방법으로서, 별도의 용매 추출 없이 바로 물 속의 휘발성 유기산의 농도를 측정할 수 있으며 높은 정확성과 재현성을 가진다. 본 연구에서는 휘발성 유기산 농도 측정을 위해 촉매모사반응의 메탄올과 샘플의 비율, 샘플 농도, 반응 온도 등 주요 인자들의 최적화를 진행하였다. 또한, 기존의 휘발성 유기산 농도 측정법 중 하나인 분광광도법과 측정 결과를 비교하였다.

A rapid and simple method for the quantitative determination of volatile fatty acids (VFAs; propionic acid, n-butyric acid, i-valeric acid and n-valeric acid) and indoles (phenol, p-cresol, 4-ethyl phenol, indole and skatole) in pig slurry and dog excrement using solid-phase micro-extraction (SPME) coupled to gas chromatography was evaluated. 50/30 ㎛ DVB/CAR/PDMS (Divinylbenzene/Carboxen/Polydimethylsiloxane) fiber was used to extract the target compounds in aqueous media. Sample amount and adsorption time was standardized for the routine analysis. Detection limits were from 0.11 to 0.15 ㎍/L for VFAs and from 0.12 to 0.28 ㎍/L for indoles and the correlations observed (R2) were 0.975～1.000. This method was applied to the pig slurry, fertilizer, compost and dog excrement. In nearly all cases, the indoles were detected in concentrations of higher than their limits of detection (DOLs). But the VFAs in swine manure were below their DOLs.

We investigated the effects of sea urchin shell powder on 2 volatile fatty acids, acetic and butyric acid, in poultry litter. A total of 60 1-d-old male broiler chicks (Arbor Acres) were allocated to 2 treatments (basal diet and 1% sea urchin shell powder) with 3 replicates of 10 birds each. During the 4-week experimental period, significant differences in acetic acid and butyric acid concentrations were observed between treatments (P < 0.05), except for acetic acid at 1 week. Additions of 1% sea urchin shell powder resulted in lower acetic and butyric acid concentrations compared to the litter of control birds. We conclude that the sea urchin shell powder used in this study might prove beneficial in reducing environmental pollution caused by poultry litter.

Biological characteristics of 5 Zanthoxylum schinifolium (Zs) fruits such as Z1 (early August), Z2 (middle August), Z3 (middle September), Z4 (early October) and Z5 (middle October) according to harvesting time were evaluated. As fruits ripened, average weight of Zs increased from 4.8mg (Z1) to 50.7mg (Z5), while moisture contents decreased from 74.6% (Z1) to 55.2% (Z5). Crude fat contents of the fruits during ripening increased from 1% (Z1) to 10.6% (Z5). The major fatty acids in Zs were palmitic (C16:0), palmitoleic (C16:1), oleic (C18:1), and linoleic (C18:2) acids. Linoleic acid (C18:2) was a main fatty acid in Z1 and Z2, whereas oleic acid (C18:1) was found as a main one in the other Zs. The ratio of unsaturated fatty acid to total fatty acids increased from 60% (Z1) to 80% (Z3~Z5) during ripening. Among ripening stages, Z4 had the highest contents of total fatty acids (3,355μg/g) and total unsaturated fatty acids (2,753μg/g). Forty six volatile compounds in Zs were also identified. The major volatile compounds were α-pinene, β-myrcene, β-ocimene, 2-nonanone, estragole, 2-undecanone, and β-caryophyllene. Major volatile components of Z1 were β-ocimene (20.8 peak area %) and α-pinene (9.7 peak area %). In Z2, estragole (30.1 peak area %) was a main volatile compound, but the contents of α-pinene (0.4 peak area %), β-myrcene (0.3 peak area %), and β-ocimene (0.6 peak area %) were lower than those in Z1. Especially, estragole used as perfumes and as a food additive for flavor was drastically increased to 91.2 (Z3) and 92% (Z4) as fruits ripened.

In this study, the detection limits of lower fatty acids in air were investigated by using Dynamic SPME(Solid Phase Micro-Extraction), i.e. improved Head Space - SPME method(HS-SPME). This Dynamic SPME, called SPDE(Solid Phase Dynamic Extraction), is the analytical method for volatile compounds in air with the extraction by using a stainless steel needle of which inner surface is coated with adsorption material and following the gas chromatographic analysis by inserting the needle into a injection port of GC and subsequently, desorption of the volatile compounds into a gas- chromatographic column. Extraction was carried out by passing the sample air through the needle with a suction pump which has been used for a detection tube. The result of measurement for the 6 lower fatty acids showed that the detection limits ranged from 0.10 ppm to 0.44 ppm and the linear correlation coefficients were over 0.99. Relative standard deviations obtained from 5 analytical repetition of a ca. 1.6 ppm standard mixture were in the range of 1.87%∼2.47%. This method has been shown to be a adequate for the measuring C2∼C5 fatty acids in air in the concentrations of over several hundreds ppb.

The objectives of this study were to evaluate the effects of chemical additives on total phosphorus (TP), soluble reactive phosphorus (SRP), and total volatile fatty acids (total VFAs) in hanwoo slurry. The treatments in this study were ferrous sulfate, alum, and aluminum chloride, and applied at the rate of 0, 0.5, and 1.0 g/25 g of hanwoo slurry. All of the chemical treatments significantly lowered TP (11 to 53% of the untreated control), SRP (41 to 99.9% of the untreated control), and total VFAs (22 to 48.5% of the untreated control) by reducing hanwoo slurry pH (3.42 to 6.86). Among these chemical amendments, addition of 0.5 g ferrous sulfate, alum, and aluminum chloride to hanwoo slurry were the best results evaluated on farms with respect to reducing negative environmental impacts. In conclusion, the results of this study indicate that the use of chemical amendments should be considered in the development of best management practices (BMPs) for the hanwoo industries.

The objectives of this study were conducted to determine the effects of two chemical amendments on volatile fatty acids (VFA) and nitrogen contents in poultry litter after broiler chicks were raised in poultry houses for 6 weeks. Two different additives were applied as a top dressing to the litter at a rate of AlCl₃∙6₂2O (200 g)+CaCO₃ (50 g) or Alum (200 g)+CaCO₃ (50 g)/kg of rice bran; untreated litter served as controls. Application of AlCl₃+CaCO₃ and Alum+CaCO₃ reduced total VFA contents by 67% and 51% at 6 weeks, respectively, compard to the control groups. The decrease in litter pH with two chemical treatments results in decreased proportion of VFA and increased nitrogen contents of the litter. These results indicate that treating AlCl₃+CaCO₃ and Alum+CaCO₃ to poultry litter offers the potential for reducing an environmental impact.