• Korean Chemical Engineering Research
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• 제56권5호
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• pp.687-693
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• 2018

바이오매스 가수분해액으로부터 당을 정제하는 동안 발효 저해물질들의 선택적인 제거 및 회수는 목질계 바이오매스로부터 바이오 알코올을 생성하는 전체 공정의 경제적 효율성을 높일 수 있다. 이 연구에서는 에멀젼형 액막계에서 페놀화합물이 없는 모사 바이오매스 가수분해액에 있는 푸란유도체가 초산 추출에 미치는 영향이 조사되었다. 특별한 조작 조건하에서 5분내에 99%이상의 초산을 추출할 수 있었으며, 이 때 푸르푸랄과 5-hydroxymethylfurfural의 추출율은 각각 10%와 4% 내외의 값을 가졌다. 또한, 원료상에 있는 푸란유도체들의 초기 농도가 높을수록 초산의 추출속도는 낮았는데, 푸르푸랄이 5-hydroxymethylfurfural 보다 그 영향이 더 컸다. 따라서, 초산 추출 전에 가수분해액으로부터 푸르푸랄을 우선적으로 제거한다면 에멀젼형 액막법이 보다 경제성이 있는 초산 제거법이 될 것으로 보인다.

• 생명과학회지
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• 제15권1호
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• pp.9-14
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• 2005

난황 단백질의 효소에 의한 가수분해에서 에탄올의 농도가 증가할수록 고형물과 단백질의 회수가 증가함을 알 수 있었다. 이것은 유화층을 에탄올의 증가가 감소시켰기 때문이다. 그러나 가수분해물에서 단백질 함량이나 sialic acid의 함량은 에탄을 농도와는 관계없이 일정하였다. 한외여과 후에 retentate에 대한 에탄올의 영향을 조사하였다. 마찬가지로 고형물의 회수는 에탄을 농도의 증가와 함께 증가하였다. 그리고 retentate에서 sialic acid의 함량은 대략 $2.5\%$정도로 일정하고 에탄올의 농도에 영향을 받지 않았다 이상의 결과로부터 난황 단백질의 효소 가수분해를 통해 sialic acid가 함유된 제품을 얻고자 할 때는 원료 난황단백질에 포함된 에탄올의 함량을 증가시킬수록 높은 수율의 제품을 얻을 수 있다. 본 실험에서는 원료 난황 단백질 중에서 $40\%$의 에탄을 함량까지는 제품 수율이 계속 증가하는 경향을 보였다. 난황 단백질 가수분해물의 한외여과에서 농축단계에서는 막 모듈의 MWCO의 차이에도 불구하고 retentate에서 총 고형물의 회수율은 비슷함을 나타내었으며, 투석에서 회수율은 MWCO가 작을수록 높아지지는 않았다. 제품에서의 sialic acid의 함량은 사용한 모듈에서 약 $2.0\%$를 나타내었다. 이것은 단백질 가수분해물에 비해 5배정도 상승한 결과이다. 본 연구에서 사용된 막 모듈 가운데서 Amicon 모듈이 제품의 회수율과 함량면에서 가장 우수한 특성을 보였다. 결론적으로 난황 단백질의 protease에 의한 가수분해에서 한외여과에 의해 순도를 높일 때 MWCO, 막 모듈의 type 그리고 운전조건 등을 잘 고려해 줄 때 최적의 조업조건을 얻을 수 있었다.

• 한국축산식품학회지
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• 제40권6호
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• pp.1033-1043
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• 2020

This study investigated the impacts of gelatin hydrolysate addition on the technological properties and lipid oxidation stability of cooked sausage. Gelatin hydrolysate was prepared from pork and duck skin gelatin, through stepwise hydrolysis using collagenase and pepsin. The cooked sausages were formulated without gelatin (control) or with 1% pork skin gelatin, 1% duck skin gelatin, 1% pork skin gelatin hydrolysate, and 1% duck skin gelatin hydrolysate. The pH, color characteristics, protein solubility, cooking loss, and textural properties of cooked sausages were evaluated, and the 2-thiobarbituric acid reactive substances (TBARS) value was measured weekly to determine lipid oxidation stability during 4 wk of refrigerated storage. Enzymatic hydrolysis of gelatin decreased protein content and CIE L* but increased redness and yellowness (p<0.05). When 1% gelatin or gelatin hydrolysate was incorporated in cooked sausage, however, little to no impacts on pH value, moisture content, protein content, color characteristics, protein solubility, and cooking loss were found (p>0.05). The addition of 1% duck skin gelatin hydrolysate increased the cohesiveness and chewiness of cooked sausages. The inclusion of 1% duck skin gelatin accelerated lipid oxidation of cooked sausages during refrigerated storage (p<0.05), whereas duck skin gelatin hydrolysate caused a lower TBARS value in cooked sausage compared to duck skin gelatin. The results show comparable effects of gelatin and gelatin hydrolysate addition on the technological properties of cooked sausages; however, the oxidative stability of raw materials for gelatin extraction should be evaluated clearly in further studies.

• Nutrition Research and Practice
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• 제3권3호
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• pp.200-207
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• 2009

This study examined the effects of com gluten (CG) and its hydrolysate consumptions on weight reduction in rats fed a high-fat diet. Eight-month-old male Sprague-Dawley rats (n=40) were fed a high-fat diet (40% calorie as fat) for 4 weeks. They were then randomly divided into four groups and fed the isocaloric diets with different protein sources for 8 weeks. The protein sources were casein (control group), intact CG (CG group), CG hydrolysate A (CGHA group, 30% of protein as peptides and 70% as free amino acids) and CG hydrolysate P (CGHP group, 93% of protein as peptides and 7% as free amino acids). Body weight gain, adipose tissue weights, nitrogen balance, absorptions of energy, protein and fat, lipid profiles in plasma, liver and feces and hepatic activities of camitine palmitoyl transferase (CPT), fatty acid synthase (FAS), malic enzyme (ME) and glucose-6-phosphate dehydrogenase (G6PDH) were assessed. The CGHA diet had the highest amount of BCAAs, especially leucine, and most of them existed as free amino acid forms. The CGHA group showed significant weight reduction and negative nitrogen balance. Protein absorption and apparent protein digestibility in the CGHA group were significantly lower than those in other groups. Adipose tissue weights were the lowest in the CGHA group. Activity of CPT tended to be higher in the CGHA group than in other groups and those of FAS, ME and G6PDH were significantly lower in the CGHA group than in other groups. In conclusion, the CGHA diet which had relatively high amounts of free amino acids and BCAAs, especially leucine, had a weight reduction effect by lowering adipose tissue weight and the activities of FAS, ME and G6PDH in experimental animals, but it seemed to be a negative result induced by lowering protein absorption, increasing urinary nitrogen excretion and protein catabolism.

• 한국수산과학회지
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• 제23권5호
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• pp.373-377
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• 1990

Volatile components of whole sardine sauce which was prepared with $7\%$ of complex enzyme-2000($2.18{\cdot}10^4\;U/g solid$), mixed with $6\%$ of invert sugar and heated at $90^{\circ}C$ for 2 hours were compared with those of without invert sugar. Thirty seven kinds were identified from the whole volatile components of hydrolysate heated without invert sugar and fourty three kinds were identified from the hydrolysate heated with $6\%$ of invert sugar. Amines were not detected from the whole volatile components of the chopped whole sardine hydrolysate. Considerable amount of 2,3-dihydrobenzofuran and 2-acetylpyrrole, a little amount of 2,5-hydrofuran, 2-ethylbutanol, 2-pyrone, 2-acetylfuran, 2,6-dimethylpyrazine, 2-acetylpyrazine, 5-methyl-2-furfural, furfuryl acetate, butylpyrrole and 2-methyl-3-hydroxypyrone were detected in the hydrolysate thermally treated with $6\%$ of invert sugar while these were not found in the hydrolysate heated without invert sugar. But the amount of 2-methyt-1-propa-not, hexane, butyl acetate and butyl alcohol were decreased, and acetic acid and butanoic acid were detected as volatile fatty acids.

• 한국축산식품학회지
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• 제34권2호
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• pp.192-199
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• 2014

The effects of adding mechanically deboned chicken (MDC) hydrolysates on the quality characteristics of imitation crab stick (ICS) during storage were investigated. ICS was prepared from Alaska Pollack, chicken breast surimi, and protein hydrolysates enzymatically extracted from MDC. ICS samples were divided into 4 groups: without protein hydrolysate (control), added with 0.5% protein hydrolysate (T1), added with 1.0% protein hydrolysate (T2), and added with 1.5% protein hydrolysate (T3). Results showed that crude protein content did not differ significantly among the ICS samples (p>0.05). ICS sample added with MDC hydrolysates had higher crude fat and ash content but lower moisture content than the control (p<0.05). Lightness was significantly lower in T2 and T3 than in the other groups at 0 and 4 wk of storage. Also, whiteness decreased in the groups contained MDC hydrolysates. Breaking force and jelly strength were higher in samples containing MDC hydrolysates compared to control samples (p<0.05). Additionally, saturated fatty acid contents were lower in the groups containing MDC hydrolysates than in control sample groups (p<0.05). Polyunsaturated fatty acid (PUFA) and essential fatty acids (EFA) were significantly higher in T2 and T3 than the control samples. In particular, all samples containing MDC hydrolysates had reduced thiobarbituric acid-reactive substances (TBARS) values at 4 wk. Free radical scavenging activity also was increased with addition of MDC hydrolysates.

• 한국축산식품학회지
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• 제30권4호
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• pp.575-581
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• 2010

This investigation was aimed at developing a ready-to-reconstitute beverage by utilizing probiotics and whey protein hydrolysates carrying bioactive peptides. Cheddar cheese whey was ultrafiltered. The 18% protein retentate was subjected to protein hydrolysis using Neutrase. The hydrolyzed retentate was further condensed to 35% total solids and spray-dried at $75^{\circ}C$ outlet air temperature. Different levels of sugar, citric acid and stabilizer were blended for spray-dried hydrolysates. Spray-dried hydrolysate was further inoculated with different levels of probiotics grown in a whey medium and dried in fluidized-bed drier at $40^{\circ}C$ to obtain a ready-to-reconstitute beverage. Hydrolysis was greatest at an enzyme:substrate ratio of 1:25 for 3 h. Spray-dried hydrolysate reconstituted to 1% protein and blended with 15% sugar, 0.2% citric acid and 0.15% xantham gum resulted in a superior product with no sedimentation. Accordingly, sugar, citric acid and xanthum gum were dry-blended with spray-dried hydrolysates. Bifidobacterium bifidum and Lactobacillus acidophilus that was grown separately in a whey medium, blended to produce 2% spray-dried hydrolysate and dried as described above resulted in a readyto-reconstitute beverage mix. The fluidized dried product typically exhibited a probiotic count of $10^8$colony forming units (CFU)/g. However, blending of probiotic to the retentate and direct spray-drying precipitously reduced the probiotic count to $10^4$ CFU/g of powder.

• 한국식품영양과학회지
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• 제42권11호
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• pp.1759-1766
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• 2013

본 연구는 오징어 간에 분포하는 효소를 활용한 은연어 육가수분해물 제조의 최적 조건과 생성된 가수분해물의 식품 및 생물 활성 특성을 조사하였다. 가열 처리한 은연어 육가수분해물 제조의 최적 조건은 가수분해 온도 $55^{\circ}C$, pH 5.5, 오징어 간의 첨가 비율 0.67%이었다. 총 구성 아미노산은 함량은 가열 및 산 처리 가수분해물에서 유의적인 차이를 보이지 않았으나, 총 유리 아미노산 함량은 조성은 산 처리가수분해물이 높았다. 한편 무기질 함량은 가열 처리 가수분해물이 높았다. Cd의 허용 기준을 고려할 때 가수분해물 제조 시 전처리 공정은 가열이 적합한 것으로 나타났다. 가열 처리한 가수분해물의 분자량은 1,000~9,500 Da이 40.0%, 500 Da이 6.7%, 200~250 Da은 12.6%, 그 이외 분자량 물질이 34.8%인 반면, 산 처리 가수분해물은 450~5,600 Da이 40.9%, 200~300 Da이 16.8%, 그 이외의 분자량이 42.3%에 해당하였다. 가수분해물은 $200{\mu}g/mL$의 농도에서 HepG2 세포에 대한 독성은 관측되지 않았다. 가수분해물의 잠재적인 적용 분야를 확인하기 위해 식품 및 건강 기능성에 대한 연구를 진행하고 있는 중이다.

• 한국식품영양과학회지
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• 제41권12호
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• pp.1677-1685
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• 2012

북해도산 오징어 간의 유효이용을 목적으로 자가소화물과 Protamex 가수분해물을 제조하고 이들의 식품학적 특성과 몇 가지 기능성을 조사하였다. 자가소화를 위한 최적 조건은 간의 함량 93.5%, pH 6.4, 항온온도 $47^{\circ}C$였으며, Protamex 가수분해의 최적 조건은 오징어 간에 대한 Protamex의 첨가비율 0.33%, pH 6.0, 가수분해온도 $55^{\circ}C$이었다. Promatex 가수분해물의 총 아미노산 조성에서 proline, cysteine 및 methionine이 검출되지 않았으나, 유리아미노산 조성에서는 검출되었다. 오징어 간, 자가소화물 및 Promatex 가수분해물의 카드늄 함량은 건조 중량으로 각각 $8.32{\pm}0.03$ mg/100 g, $3.56{\pm}0.02$ mg/100 g, $13.26{\pm}0.04$ mg/100 g으로서 식품안전 규정 이하의 농도로 감소시키기 위한 별도의 공정이 필요하다. 자가소화물의 주요 저분자 물질의 분자량은 1.0~1.5 kDa인 반면, Protamex 가수분해물은 210~470 Da이었다. 자가소화물과 Protamex 가수분해물 간에 표면 소수성, 유화활성 지표, 유화안정성, 지방 및 수분 흡착능은 큰 차이를 보이지 않았으며, 높은 ACE 효소 저해효과가 관측되었다. 한편 HepG2 세포주에 대한 독성은 200 ${\mu}g/mL$까지 관측되지 않았다.

• 대한약리학회지
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• 제12권1호
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• pp.57-62
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• 1976

Using modified technique of Schmidt et al, as described previously (Korean J. Pharmacol 9 : 17, 1973), the stomach of female rats were perfused with physiological saline under urethane anesthesia. The acid-secretory response of the perfused stomach to i.v. hypertonic glucose (50%), casein hydrolysate (20%) or saline (6%) solution were studied with or without histamine or methacholine stimulation. A significant decrease of acid secretion from the rat stomach was induced by i.v. hypertonic glucose or saline solution. The histamine-stimulated acid secretion was also decreased by simultaneous administration of the hypertonic glucose or saline. However, methacholine-stimulated acid response was not affected by the hypertonic glucose. Intravenous infusion of 20% casein hydrolysate solution resulted in an increase in acid output from the stomach under histamine stimuli. These results lead to the conclusion that the inhibitory responses of acid secretion due to i.v. hypertonic glucose solution are brought through the effect of histaminergic, not cholnergic mechanism(s) in the gastric secretion.