• Fisheries and Aquatic Sciences
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• 제22권1호
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• pp.1.1-1.8
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• 2019

Five experimental diets were formulated to evaluate the effects of dietary enzymatically hydrolyzed tuna by-product on growth, non-specific immune responses, and hematology of juvenile rainbow trout (Oncorhynchus mykiss). A basal diet with 50% of fishmeal was used as control (CON) and four other diets replaced 12.5% ($TBB_{12.5}$), 25% ($TBB_{25}$), 37.5% ($TBB_{37.5}$), and 50% ($TBB_{50}$) of fish meal in the CON diet. Juvenile rainbow trout ($4.87{\pm}0.05g$) were randomly distributed into 15 tanks (50 L) and fed 3-4% of wet body weight two times a day. At the end of 7 weeks of feeding trial, weight gain, specific growth rate, feed efficiency, and protein efficiency ratio of fish fed CON diet were significantly higher than those of fish fed $TB_{50}$ diet (P < 0.05). But there were no significant differences among fish fed CON, $TBB_{12.5}$, $TBB_{25}$, and $TBB_{37.5}$ diets (P > 0.05). There were no significant differences in GPT levels among fish fed CON, $TBB_{12.5}$, $TBB_{25}$, and $TBB_{37.5}$ diets. Also, there were no significant differences in lysozyme, superoxide dismutase, glucose, and total protein levels in all experimental diet (P > 0.05). The broken-line analysis indicated that the minimum dietary level of enzymatically hydrolyzed tuna by-product to replace fishmeal could be 29.7% in rainbow trout. These results indicated that the optimum level of dietary enzymatically hydrolyzed tuna by-product could replace greater than 29.7% but less than 37.5% of fishmeal in juvenile rainbow trout diet.

• Journal of Dairy Science and Biotechnology
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• 제31권2호
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• pp.195-200
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• 2013

The ripening of cheese allows for the development of characteristic taste and flavour, nutritional substances, bio-active components and texture, helping to improve quality. Many different microbiological, biochemical and nutritional changes occur during the process depending on the quality of raw milk, added cultures and enzymes, as well as specific processing and ripening conditions. During the ripening lactose is hydrolyzed to lactic, propionic and acetic acid, helping to reduce potential effects of the problem of lactose intolerance. Fat is hydrolyzed to butyric, propionic and conjugated linoleic acid, which function as bio-active substances. Protein is hydrolyzed to different peptides and amino acids which all show various bio-activities. However, errors of cheese ripening can happen and affect the quality of the product. To guarantee good quality cheese the process needs to be managed carefully with the right microbes used and ensuring cleanliness of processing facilities, staff, ventilation and hazard analysis and critical control points (HACCP). Research into and controlling of ripening technology is crucial for producing high quality cheeses.

• 한국식품과학회지
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• 제24권4호
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• pp.330-334
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• 1992

아미노산 간장의 풍미를 높이기 위해 S. rouxii에 의한 알코올 발효시 아미노산 간장내에 존재하는 NaCl, 색소물질 및 glucose의 농도가 S. rouxii의 생육에 미치는 영향과, 발효온도, 통기속도 등 발효환경요인이 S. rouxii의 생육 및 알코올 발효에 미치는 영향을 관찰하였다. 아미노산 간장내 NaCl 6%(w/v) 까지는 균체 생육에 영향을 미치지 않았으나, 그 이상의 농도에서는 생육을 저해하였으며, 아미노산 간장 중 존재하는 색소물질은 균체 생육에 영향을 미치지 않는 것으로 밝혀졌다. 또 아미노산 간장에 첨가된 glucose의 농도가 25%(w/v)까지는 균체 생육을 크게 저해하지 않았다. S. rouxii의 생육 및 알코올 발효의 최적 온도는 $25^{\circ}C$이며, 최대 알코올 생산을 위한 최적 통기속도는 0.5 vvm이었다. 이때 아미노산 간장내 최대 알코올 농도는 4.2%(w/v)였다.

• 산업식품공학
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• 제21권2호
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• pp.138-142
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• 2017

소금의 과량 섭취가 성인병, 생활습관병 등 여러 건강상에 문제가 있다는 보고에 의해 이를 해결하기 위한 다양한 연구가 진행되고 있다. 우리나라도 전통적인 식생활 습관에 의해 많은 소금을 섭취하고 있어 이를 개선하기 위한 범국가적으로 노력하고 있다. 최근 콩단백질을 활용한 우리나라의 발효 식품인 간장 등이 짠맛을 증진한다는 보고가 있어 이에 대한 연구가 활발히 이루어지고 있다. 본 연구에서는 간장의 주원료인 콩단백질을 가수분해하여 얻어진 효소가수분해(eHISP)의 짠맛 증진 효과에 대해 살펴보았다. 동일한 소금농도의 용액에 eHISP의 첨가량을 달리하였을 때 첨가량이 증가할수록 짠맛 증진효과도 증가하여, 50 mmol/L의 용액에 2%의 eHISP를 첨가하였을 경우 $70.13%{\pm}5.45%$의 짠맛 강도를 인지하였으며, 용액의 소금농도가 낮을수록 eHISP의 첨가에 따른 짠맛 증진효과가 더 크게 나타났다. 이러한 짠맛 증진효과는 콩단백질의 주요 아미노산 성분인 glutamic acid, aspartic acid와 효소가 수분해에 포함되어 있는 arginyl dipeptide와 같은 저분자량의 펩타이드 등의 상호작용에 의한 것으로 보인다. 0.1%에서 2%까지 eHISP의 첨가량을 달리하였을 경우 최소 2%에서 최대 39%의 짠맛 증진 효과를 나타내어 분리대두단백질의 효소가수분해물이 짠맛 증진물질로서 활용 가능성이 있는 것으로 판단된다.

• 한국식품과학회지
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• 제29권5호
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• pp.839-846
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• 1997

Meat-like flavor를 생성하고자 당과 아미노산 혼합액인 0.2 M cystine-0.1 M lactose-0.1 M maltose를 대조구로 하여 천연 조미향상물질(HVP, HAP, YE)을 첨가하였다. 천연 조미향상물질의 첨가는 대조구에 농도별로 단독 첨가하였으며 단독 첨가시 선정된 농도의 HVP, HAP나 YE를 혼합하여 그 영향을 비교하였다. Meat-like flavor 생성에 유사한 조건인 $100^{\circ}C$에서 8시간 동안 마이야르 반응시킨 반응액은 흡광도, 색, 관능적 성질 및 휘발성 향기성분을 분석하였다. 그 결과 HVP, HAP, YE를 첨가 농도별로 첨가하였을 때 반응 시간과 첨가 농도가 증가할수록 420 nm와 278 nm에서의 흡광도가 증가하였다. 또한 첨가 농도별 색의 변화는 HVP, HAP와 YE 모두 b값은 증가 경향을 나타낸 반면 L값은 감소 경향을 나타내었다. 관능 검사에서 meat flavor에 근접한 각 조미향상물질의 첨가 농도는 1.16% HVP, 0.94% HAP, 1.48% YE이었고 가장 meat flavor에 근접한 반응액은 대조구에 HVP 1.16%와 HAP 0.94%를 혼합 첨가한 반응액이었다. 대조구와 HVP 단독 첨가구 및 HVP와 HAP 혼합 첨가구에 대한 향기 성분을 비교하고자 GC/MS로 분석한 결과 hydrocarbon류 1종, aldehyde류 9종, ketone류 5종, ester류 1종, alcohol류 5종, aromatics(benzene)류 2종, furan류 2종, sulfur compound류 1종을 확인할 수 있었다.

• 한국식품영양과학회지
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• 제45권9호
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• pp.1279-1284
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• 2016

식물성 단백질 급원인 탈지대두박에 Flavourzyme$^{(R)}$(F), Neutrase$^{(R)}$(N), Alcalase$^{(R)}$(A), Protamex$^{(R)}$(P)의 단백질 분해효소를 작용시켰을 때 짠맛을 많이 생성하는 조건을 확인하고자 하였다. 효소처리 순서를 달리하여 제조한 enzyme hydrolyzed vegetable protein의 고형분 함량은 1차 Neutrase $^{(R)}$(N), 2차 Alcalase$^{(R)}$(A), 3차 Flavourzyme$^{(R)}$(F), 4차 Protamex$^{(R)}$(P)를 처리한 NAFP 처리구에서 5.60%로 가장 높은 값을 나타내었으나 고형분 함량에서는 효소의 처리 순서가 큰 영향을 미치지 않는 것을 알 수 있었다. 아미노태질소 함량은 24개의 처리구들 중에서 ANFP(102.76 mg%)와 APNF(102.85 mg%) 처리구가 통계적으로 높은 값을 나타내었다. 정량묘사분석 결과 짠맛은 PNFA(11.81) 처리구가 통계적으로 유의차를 나타내며 높은 값을 나타내었고, NPAF(10.14), FPNA(10.00), APNF(9.80), NAFP(9.76), AFNP(9.57), APFN(9.52), NPFA(9.50) 처리구가 처리구간에 통계적으로 유의차를 나타내지 않으며 다음으로 높은 값을 나타내었다. 감칠맛은 모든 처리구에서 통계적으로 유의차를 나타내지 않았다. 쓴맛 후미는 AFPN(5.67) 처리구가 가장 높은 값을 나타내었으며 FAPN(2.38), PNAF(2.62), NAPF(2.48) 처리구에서 낮은 값을 나타내었다. 관능평가 묘사분석 결과를 주성분 분석한 결과 PNFA, NAFP, APFN, NPAF, FPNA, NPFA, APNF 처리구는 짜고 감칠맛 나는 맛을 낼 수 있는 효소처리법이었다. 따라서 이들 효소의 처리 순서가 짜고 감칠맛 나는 식물단백효소 분해물의 제조에 바람직한 방법임을 알 수 있었다.

• Journal of Animal Science and Technology
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• 제65권6호
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• pp.1290-1307
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• 2023

This study investigated the effect of processed forms (defatted or hydrolyzed) of black soldier fly larvae (Hermetia illucens L., BSFL) as a protein substitute on broilers. Experiment 1 was a feeding experiment, and Experiment 2 was a metabolism experiment. In Experiment 1, a total of 120 day-old Arbor Acres broilers (initial body weight 39.52 ± 0.24 g) were used for 28 days. There were 8 replicate pens, and 5 broilers were assigned to each pen. In Experiment 2, a total of 36 day-old broilers (initial body weight 39.49 ± 0.21 g) were used for the metabolism trial. There were 2 broilers in a metabolism cage and six replicate cages per treatment. The dietary treatments were as follows: a basal diet (CON), a basal diet without fishmeal and substitute with defatted BSFL (T1), a basal diet without fishmeal and a substitute with hydrolyzed BSFL (T2). In Experiment 1, during the entire experimental period, the T2 group significantly increased (p < 0.05) body weight gain and feed intake compared to the CON and T1 groups. The feed conversion ratio showed a lower tendency (p = 0.057) in the T2 group than in the CON and T1 groups. At 2 weeks, the CON and T2 groups were significantly higher (p < 0.05) crude protein (CP) digestibility than the T1 group. At 4 weeks, the total protein level significantly increased (p < 0.05) in the CON and T2 groups compared to the T1 group. In Experiment 2, the CP digestibility significantly increased (p < 0.05) in the T2 group compared to the CON and T1 group at weeks 2 and 4. At week 4 amino acid digestibility, the T2 group significantly increased (p < 0.05) lysine, methionine, tryptophan, and glycine digestibility compared to the T1 group. There was no difference in fecal microbiota among the treatment groups. In conclusion, feeding hydrolyzed BSFL as a fishmeal substitute in broiler diets improved growth performance, CP digestibility, and specific amino acid digestibility. Therefore, it is considered that hydrolyzed BSFL in broiler diets can be sufficiently used as a new protein source.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1917-1923
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• 2004

Although the proteolytic activity of the Cu(II) complex of cyclen (Cyc) is greatly enhanced upon attachment to a cross-linked polystyrene (PS), the Cu(II)Cyc-containing PS derivatives reported previously hydrolyzed only a very limited number of proteins. The PS-based artificial metalloproteases can overcome thermal, mechanical, and chemical instabilities of natural proteases, but the narrow substrate selectivity of the artificial metalloproteases limits their industrial application. In the present study, artificial metalloproteases exhibiting broad substrate selectivity were synthesized by attaching Cu(II)Cyc to a PS derivative using linkers with various structures in an attempt to facilitate the interaction of various protein substrates with the PS surface. The new artificial metalloproteases hydrolyzed all of the four protein substrates (albumin, myoglobin, ${\gamma}$-globulin, and lysozyme) examined, manifesting $k_{cat}/K_m$ values of 28-1500 $h_{-1}M_{-1}$ at 50 $^{\circ}C$. The improvement in substrate selectivity is attributed to steric and/or polar interaction between the bound protein and the PS surface as well as the hydrophobicity of the microenvironment of the catalytic centers.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.733-738
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• 2007

An extracellular exoinulinase($2,1-\beta-D$ fructan fructanohydrolase, EC 3.2.1.7), which catalyzes the hydrolysis of inulin into fructose and glucose, was purified 23.5-fold by ethanol precipitation, followed by Sephadex G-100 gel permeation from a cell-free extract of Kluyveromyces marxianus YS-1. The partially purified enzyme exhibited considerable activity between pH 5 to 6, with an optimum pH of 5.5, while it remained stable(100%) for 3 h at the optimum temperature of $50^{\circ}C$. $Mn^{2+}\;and\;Ca^{2+}$ produced a 2A-fold and 1.2-fold enhancement in enzyme activity, whereas $Hg^{2+}\;and\;Ag^{2+}$ completely inhibited the inulinase. A preparation of the partially purified enzyme effectively hydrolyzed inulin, sucrose, and raffinose, yet no activity was found with starch, lactose, and maltose. The enzyme preparation was then successfully used to hydrolyze pure inulin and raw inulin from Asparagus racemosus for the preparation of a high-fructose syrup. In a batch system, the exoinulinase hydrolyzed 84.8% of the pure inulin and 86.7% of the raw Asparagus racemosus inulin, where fructose represented 43.6mg/ml and 41.3mg/ml, respectively.

• 한국식품조리과학회지
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• 제21권2호
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• pp.217-224
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• 2005

The storage characteristics of frozen soy yogurt prepared with hydrolyzed soy protein isolates were evaluated. In order to facilitate lactic fermentation bacteria grow and produce lactic acid as fast rate as possible, soy protein isolate(SPI) was hydrolyzed using two kinds of proteases; bromelain and a-chymotrypsin. The cultural systems employed thereafter for lactic fermentations were Bifidobacterium bifidum or B. bifidum and Lactobacillus bulgaricus. The viable cell counts, normal- and bile acid tolerances from the mixed cultures of B. bifidum and L. bulgaricus decreased sharply during the initial first 3 days of frozen storage and then showed a gradual decrease thereafter. Melt-down percent of the all frozen products have been favorably affected as was shown by less melting at raised testing temperature during 28 days of frozen storage except for the initial 3 days during which a minor change has been observed. Among the various volatile flavor components, the contents of acetaldehyde, acetone, diacetyl and methanol generally increased during the frozen storage. In sensory test, the frozen soy yogurt prepared with a-chymotrypsin and mixed culture of B. bifidum and L. bulgaricus was the most desirable, the highest scores in sourness, bitterness and mouthfeel.