• 한국축산식품학회지
• /
• 제35권3호
• /
• pp.350-359
• /
• 2015

This review focuses on the enhanced functional characteristics of enzymatic hydrolysates of whey proteins (WPHs) in food applications compared to intact whey proteins (WPs). WPs are applied in foods as whey protein concentrates (WPCs), whey protein isolates (WPIs), and WPHs. WPs are byproducts of cheese production, used in a wide range of food applications due to their nutritional validity, functional activities, and cost effectiveness. Enzymatic hydrolysis yields improved functional and nutritional benefits in contrast to heat denaturation or native applications. WPHs improve solubility over a wide range of pH, create viscosity through water binding, and promote cohesion, adhesion, and elasticity. WPHs form stronger but more flexible edible films than WPC or WPI. WPHs enhance emulsification, bind fat, and facilitate whipping, compared to intact WPs. Extensive hydrolyzed WPHs with proper heat applications are the best emulsifiers and addition of polysaccharides improves the emulsification ability of WPHs. Also, WPHs improve the sensorial properties like color, flavor, and texture but impart a bitter taste in case where extensive hydrolysis (degree of hydrolysis greater than 8%). It is important to consider the type of enzyme, hydrolysis conditions, and WPHs production method based on the nature of food application.

• Preventive Nutrition and Food Science
• /
• 제20권3호
• /
• pp.183-189
• /
• 2015

In the present study, an optimum protease was selected to hydrolyze the egg white liquid protein for the antioxidant peptides. Alcalase treatment yielded the highest amount of ${\alpha}$-amino groups (15.27 mg/mL), while the control (no enzymatic hydrolysis) showed the lowest amount of ${\alpha}$-amino groups (1.53 mg/mL). Alcalase also gave the highest degree of hydrolysis (DH) value (43.2%) and was more efficient for egg white liquid hydrolysis than the other enzymes. The Alcalase hydrolysate had the highest radical-scavenging activity (82.5%) at a concentration of 5.0 mg/mL. The conditions for enzymatic hydrolysis of egg white liquid with Alcalase were selected as substrate : water ratio of 2:1. Five percent Alacalse treatment did not show significant (P>0.05) increases of DH and ${\alpha}$-amino nitrogen content after 24 hhydrolysis. Thirty two hour-hydrolysis with 5% Alcalase is sufficient to make antioxidative egg white liquid hydrolysate from egg white liquid. DPPH and ABTS radical-scavenging activities were significantly (P<0.05) higher after enzymatic digestion. These results suggest that active peptides released from egg-white protein are effective radical-scavengers. Thus, this approach may be useful for the preparation of potent antioxidant products.

• 한국식품영양과학회지
• /
• 제31권4호
• /
• pp.653-657
• /
• 2002

멸치 액젓 발효잔사 및 간장박을 원료로 하여 기능성 효소분해간장을 제조하기 위한 전처리 과정으로서 단백질 가수분해 효소인 Flavourzym 500M $G^{TM}$에 의한 단백질 가수분해물의 제조를 위하여 반응표면분석법 이용하여 최적 제조조건을 설정하고자 하였다. 그 결과 HR (%) : 28.157+1.929E/S +1.818Time+2.038Temp -1.093Tem $p^2$와 같은 회 귀방정식 모형을 얻었으나 정상점이 안장점을 나타내어 능선분석(반경 1.0)을 수행하였고, 최적조건은 기질에 대한 효소의 농도(E/S)=0.49%, 가수분해 시간(Time)=3.55 hr 및 가수분해 온도(Temp)62.5$^{\circ}C$로 설정되었다 간장박은 멸치액젓 발효관사의 불쾌취와 맛을 masking시키는 효과가 있는 것으로 나타났으나 가수분해물 자체만으로는 제품으로 이용되기에는 관능적 특성이 다소 낮은 상태를 보이고 있었다.

• 한국식품영양과학회지
• /
• 제40권2호
• /
• pp.229-234
• /
• 2011

본 연구에서는 4년근 인삼의 활용도를 높이기 위하여 효소적 가수분해 조건에 따른 품질 특성을 조사하였다. 인삼은 증숙 후 분쇄하여 가수분해 효소제 A, B, C 및 D 4종에 처리에 따른 품질특성을 조사한 결과 pH 5.5~5.6, 당도 4.0~4.33으로 큰 차이가 없었다. 조사포닌 함량은 D 효소제에서 가장 높았으며, B, C 및 A 순으로 나타났다. D 효소제의 농도 0.3%(w/w)까지 조사포닌, 환원당 및 총당 함량이 증가하였으며 이후에는 농도에 따른 차이는 없었다. 가수분해시간이 경과함에 따라 유효성분이 증가하였으나 3시간 이후 큰 변화는 없었으며, $60^{\circ}C$로 처리하였을 때 조사포닌 함량이 높게 나타났다. 이상의 실험결과 D 효소제, 효소제 농도 0.3% (w/w)로 $60^{\circ}C$에서 3시간의 조건이 가장 적합한 나타났으며 이때 환원당, 총당 및 조사포닌 함량은 각각 18.11, 36.21 및 4.23 mg/g으로 확인되었다. 따라서 효소적 가수분해 방법은 4년근 인삼의 유효성분 증가에 효과적으로 다양한 활용 방법이 기대되었다.

• Journal of the Korean Wood Science and Technology
• /
• 제40권2호
• /
• pp.78-90
• /
• 2012

Soybean hull is an attractive feedstock for glucose production. To increase the glucose conversion in acid hydrolysis, a pretreatment method combined steam explosion with alkali pretreatment for soybean hull was studied. For first step pretreatment, steam explosion conditions (log Ro 2.45) were optimized to obtain maximum solid recovery and cellulose content. In the second step pretreatment, the conditions for potassium hydroxide pretreatment of steam exploded soybean hull were optimized by using RSM (response surface methodology). The optimum conditions for minimum lignin content were determined to be 0.6% potassium hydroxide concentration, $70^{\circ}C$ reaction temperature and 198 min reaction time. The predicted lignin content was 2.2% at the optimum conditions. Experimental verification of the optimum conditions gave the lignin content in similar value with the estimated value of the model. Finally, glucose conversion of pretreated soybean hull using acid hydrolysis resulted in $97.1{\pm}0.4%$. This research of two-step pretreatment was a promising method for increasing the glucose conversion in the cellulose-to-glucose process.

• KSBB Journal
• /
• 제23권2호
• /
• pp.131-134
• /
• 2008

캠페롤은 항산화, 항염등의 성질을 가지고 있지만 생산이 쉽지가 않다. 차의 씨를 가공하고 발생하는 부산물 (tea seed extract)에는 캠페롤과 당이 결합되어 있는 형태인 camelliaside A와 camelliaside B가 포함되어 있다. 본 실험에서는 캠페롤을 효소의 가수분해에 의하여 생산하였다. 가장 효과적인 효소는 $pectinex^{(R)}100L$ 이며, 효소 반응에서 캠페롤은 48시간내에 생산되었다. 반응 최적 조건은 $40^{\circ}C$, pH 4이며 생산의 최적조건하에서 차 부산물 1 kg당 1.6 g의 캠페롤이 생산되었고 약 80%의 캠페롤이 침전되었다. 효소반응에 의한 캠페롤 생산법은 생산물의 회수가 용이한 효과적인 방법임을 알 수 있다.

• Mass Spectrometry Letters
• /
• 제8권3호
• /
• pp.53-58
• /
• 2017

Glycated hemoglobin ($HbA_{1c}$) has been commonly used to screen and diagnose for patients with diabetes mellitus. Here the accelerated procedure of microwave-assisted sample treatment from acid hydrolysis to enzyme digestion followed by isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) was optimized and applied to measure $HbA_{1c}$ in an effort to speed up analysis time. First, two signature peptides of $HbA_{1c}$ and hemoglobin $A_0$ were certified with amino acid analysis by setting optimized acid hydrolysis conditions to $150^{\circ}C$, 1.5 h and $10{\mu}M$ sample concentration in 8 M hydrochloric acid. Consequently, the accurate certified peptides above were used as calibration standards to implement the proteolytic procedure with endoproteinase Glu-C at $37^{\circ}C$, 700 W for 6 h. Compared to the traditional method, the microwave heating not only shortened dramatically sample preparation time, but also afforded comparable recovery yields. The optimized protocol and analytical conditions in this study are suitable for a primary reference method of $HbA_{1c}$ quantification with full SI-traceability and other similar proteins in complex biological samples.

• Fibers and Polymers
• /
• 제6권1호
• /
• pp.13-18
• /
• 2005

PLA/LPCL/HPCL blend fibers composed of poly (lactic acid) (PLA), low molecular weight poly ($\varepsilon$-caprolactone) (LPCL), and high molecular weight poly ($\varepsilon$-caprolactone) (HPCL) were prepared by melt blending and spinning for bioab­sorbable filament sutures. The effects of blending time and blend composition on the X-ray diffraction patterns and tensile properties of PLA/LPCL/HPCL blend fibers were characterized by WAXD and UTM. In addition, the effect of in vitro degra­dation on the weight loss and tensile properties of the blend fibers hydrolyzed during immersion in a phosphate buffer solu­tion at pH 7.4 and 37$^{\circ}C$ for 1-8 weeks was investigated. The peak intensities of PLA/LPCL/HPCL blend fibers in X-ray diffraction patterns decreased with an increase of blending time and LPCL contents in the blend fibers. The weight loss of PLA/LPCL/HPCL blend fibers increased with an increase of blending time, LPCL contents, and hydrolysis time while the tensile strength and modulus of the blend fibers decreased. The tensile strength and modulus of the blend fibers were also found to be increased with an increase of HPCL contents in the blend fibers. The optimum conditions to prepare PLA/LPCL/HPCL blend fibers for bioabsorbable sutures are LPCL contents of $5 wt\%, HPCL contents of $35 wt\%, and blending time of 30 min. The strength retention of the PLA/LPCL/HPCL blend fiber prepared under optimum conditions was about $93.5\% even at hydrolysis time of 2 weeks.

• Korean Chemical Engineering Research
• /
• 제53권2호
• /
• pp.199-204
• /
• 2015

지방산 생산을 위한 돈지의 아임계수 가수분해 공정을 최적화하기 위하여 17-run 중심합성법(central composite design)에 기초한 반응표면법(response surface methodology)이 사용되었다. 반응 온도, 오일 대비 물의 몰 비, 반응 시간과 같은 변수 및 이들의 상관관계가 지방산 함량에 미치는 영향을 조사하였으며, 지방산 함량을 예측하기 위하여 2차 다항 회귀방정식이 제안되었다. 최대 지방산 함량을 얻을 수 있는 반응 조건은 $288.5^{\circ}C$, 39.5몰 비, 29.5분이었으며, 이 조건에서의 예측 및 실제 지방산 함량은 각각 97.06% 및 96.99%였다.

• Journal of Ginseng Research
• /
• 제34권1호
• /
• pp.68-75
• /
• 2010

This study sought to optimize the extraction and enzymatic treatment conditions of Panax ginseng leaves, stems, and roots for the production of fermented ginseng. The optimization enhanced the extraction of total saccharide, a nutrient and growth-activating factor for Lactobacillus bacteria. The hydrolysis of ginseng leaves, stems, and roots was tested with eight enzymes (Pentopan, Promozyme, Celluclast, Ultraflo, Pectinex, Ceremix, Viscozyme, and Tunicase). The enzymatic hydrolysis conditions were statistically optimized by the experimental design. Optimal particle size of ginseng raw material was <0.15 mm, and optimal hydrolysis occurred at a pH of 5.0-5.5, a reaction temperature of 55-$60^{\circ}C$, a Ceremix concentration of 1%, and a reaction time of 2 hr. Ceremix produced the highest dry matter yield and total saccharide extraction. Ginseng leaves were found to be the most suitable raw material for the production of fermented ginseng because they have higher carbohydrate and crude saponin contents than ginseng roots.