• The Korean Journal of Food And Nutrition
• /
• v.10 no.4
• /
• pp.521-527
• /
• 1997

A liquefied seasoning material was manufactured by using the enzymatic hydrolysis for the benefit of highly effective utilization of cockle shell by-product, and their quality was investigated. The weight ratio of by-product to whole cockle shell was 32.7%, and the contents of moisture and crude protein in the raw cockle shell by-product were 83.1% and 10.7%, respectively. The optimal concentrations of protease such as Protease N. P.(Pacific Chemical Co.) and Alcalase(Noo co), used in order to reduced the hydrolysis period, were effective at 4%(w/w), and optimal hydrolyzing time was 8 hours and after 8 hours were little changed. To improve flavor of the liquefied seasoning material, by Maillard reaction used thermal treatment, addition of glucose was very effective. And addition in hydrolysate with 10% glucose, 9% table salt, 2% starch and 0.5% caramel were suitable for promotion of taste. Total nitrogen and amino type nitrogen in the product were 1,607mg% and 1,264mg%, respectively. And the ratio of amino type nitrogen to the total nitrogen was 78.6%. The major free amino acid were glutamic acid, lysine, leucine, valine and aspartic acid, and content of glutamic acid was 1,027.5mg%.

• Korean Journal of Food Science and Technology
• /
• v.26 no.4
• /
• pp.436-441
• /
• 1994

To investigate the lowering effects of in vitro enzymatic hydrolysis by the treatment of chymotrypsin, trypsin, pancreatin, or protease from Aspergillus oryzae on the antigenicity of whey protein isolate (WPI) against rabbit anti ${\alpha}-LA$ antiserum, competitive inhibition ELISA (cELISA) and passive cutaneous anaphylaxis (PCA) test using guinea pig were performed. The results of cELISA showed that the monovalent antigenicity of the whey protein hydrolysates (WPH) to the antiserum was decreased to $10^{-2.5}-10^{-5.5}$ and less by the hydrolysis. The monovalent antigenicity of the WPH hydrolyzed by trypsin, or protease from Asp. nryzae was much lowered by the pretreatment of heat denaturation. The antigenicity of the WPH hydrolyzed by chymotrypsin, trypsin, or pancreatin was much lowered by the pretreatment of pepsin. Especially, the antigenicity of TDP (trypic hydrolysate with pretreatment of heat and pepsin) was found almost to be removed. However, there was not consistency between degree of hydrolysis(DH) and the monovalent antigenicity of the WPH. By the heterologous PCA it was found that all of the PGPH lost the polyvalent antigenicity regardless of the pretreatments although WPI and ${\alpha}-LA$ had the positive high antigenicity. The results suggested that the peptides derived from ${\alpha}-LA$ in WPH could bind specific antibodies but they could not induce allergy. Therefore, it was elucidated that the allergenicity of ${\alpha}-LA$ in whey protein could be destroyed easily by the enzymatic hydrolysis.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.45 no.6
• /
• pp.545-552
• /
• 2012

This study developed a natural seasoning (NS) and characterized its food components. Hydrolysate from Alaska Pollock Theragra chalcogramma heads and sea tangle Laminaria japonica byproduct were obtained by incubating them with Neutrase for 4 h. NS was prepared by mixing sorbitol 2%, salt 2%, ginger powder 0.04%, garlic powder 0.2%, onion powder 0.2% and inosine monophosphate (IMP) 0.1% based on concentrated hydrolysates from Alaska pollock head and sea tangle byproduct before vaccum filtering. The proximate composition of NS was 82.7% moisture, 9.0% crude protein, and 5.1% ash. It had a higher crude protein content than commercial anchovy sauce (CS), it was lower in moisture and ash. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and angiotensin-I converting enzyme (ACE) inhibiting activity of NS were 90.1% and 88.9%, respectively, which were superior to those of CS. The free amino acid content and total taste value of NS were 1,626.0 mg/100 mL and 165.86, respectively, which were higher than those of CS. According to the results of taste value, the major free amino acids were glutamic acid and aspartic acid. In the sensory evaluation, the color and taste of NS were superior to those of CS. No difference in fish odor between NS and CS was found.

• Journal of Dairy Science and Biotechnology
• /
• v.21 no.2
• /
• pp.97-104
• /
• 2003

It is extremely important to destroy the antigenicity of milk proteins for dietetic treatment of infants with milk allergy. Enzymatic digestion of milk protein is not only effective for destroying antigenicity, but it also is less liable to alter the nutritive value. Bovine casein was hydrolyzed with eight different commercial proteases derived from bacterias or fungi, either individually or in combination to eliminate protein allergenicity. The average molecular weight of casein hyrdolysates determined by size exclusion chromatography is about 550${\sim}$2,300 dalton range. Antigenicity of the casein hyrdolysates was not detected by heterologous passive cutaneous anaphylaxis in guinea pig-rabbit antiserum system. The inhibition test on the enzyme-linked immunosorbent assay(ELISA) showed that the antigenicity of casein hydrolysates is lowed up to 1/8,000 than that of intact bovine casein. As the enzyme reaction was carried out by the combination of bacterial and fungal protease, casein hydrolysates showed much lower bitterness and antigenicity. It suggests that these hydrolysates will be applied to many kinds of foods including the development of hypo-allergenic infant formula.

• Applied Biological Chemistry
• /
• v.47 no.4
• /
• pp.384-389
• /
• 2004

The purified ${\beta}-mannanase$ hydrolyzed various gums to mannose, ${\beta}-1,4-mannobiose$, $Gal^3Man_4$, and D.P 7 of galactosyl mannooligosaccharide, and isolated from the enzymatic hydrolysate for 24 hrs reaction by activated carbon column chromatography and Sephadex G-25 column chromatography. For the elucidate of antioxidant action of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ and DP 7 of galactosyl mannooligosaccharide and urea derivatives, coloration, reducing power, antioxidant activity and DPPH test were accomplished. The coloration was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and urea. TLC of reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and ureas showed new reaction products, respectively. but except reaction mixture of ${\beta}-1,4-mannobiose$ and urea. The reducing power was high at reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and phenylthiourea. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea showed similar radical scavenging activities on DPPH to activity of AsA. The reaction mixture of ${\beta}-1,4-mannobiose$, $Gal^3Man_4$ D.P 7 and thiourea, phenythiolurea shown strong antioxidative activites on the oxidation of linoneic acid.

• Applied Biological Chemistry
• /
• v.47 no.4
• /
• pp.379-383
• /
• 2004

For the elucidation of substrate specificity to the brown copra meal by Bacillus sp. ${\beta}-mannanase.$, the enzymatic hydrolysate after 24 hr of reaction was heated in a boiling water bath for 10 min, and then centrifuged to remove the insoluble materials from hydrolysates. The major hydrolysates composed of D.P 5 and 7 galactosyl mannooligosaccharides. For the separate of galactosyl mannooligosaccharides, the supernatant solution of 150 ml was put on a first activated carbon column. The column was then washed with 5 l of water to remove mannose and salts. The oligosaccharides in the column were eluted by a liner gradient of $0{\sim}30%$ ethanol, at the flow rate of 250 ml per hour. The sugar composition in each fraction tubes was examined by TLC and FACE analysis. The combined fraction from F3 was concentrated to 30 ml by vacuum evaporator. Then put on a second activated carbon column. The oligosaccharides in the column were eluted by a liner gradient of $0{\sim}30%$ ethanol (total volume: 5 l), at the flow rate of 250 ml per hour. The eluent was collected in 8 ml fraction tubes, and the total sugar concentration was measured by method of phenol-sulfuric acid. The major component of F2 separated by 2nd activated carbon column chromatography were identified $Gal^3Man_4(6^3-mono-{\alpha}-D-galactopyranosyl-{\beta}-mannotetraose)$. To investigate the effects of brown copra meal galactomannooligosaccharides on growth of Bifidobacterium longum, B. bifidum were cultivated individually on the modified-MRS medium containing carbon source such as $Gal^3Man_4$, compared to those of standard MRS medium.

• Korean Journal of Food Science and Technology
• /
• v.46 no.6
• /
• pp.716-722
• /
• 2014

Aminopeptidase-active fractions from crude extract of the hepatopancreas of a common squid (Todarodes pacificus) were obtained using acetone (AC; 30-40%) and ammonium sulfate precipitation (AS; 60-70% saturation), anion exchange (AE-II; 0.2 M NaCl) and gel filtration chromatography (GF-I; 30-50 kDa), respectively. The debittering capacity of GF-I fraction based on the aminopeptidase activity (89.2 U/mg), recovery (56.6%) and sensory evaluation (1.0) was better than that of other fractions. Release of amino acids increased as incubation time was increased, and the bitterness of the enzyme reaction mixtures decreased. Incubation with the GF-I fraction for 24 h resulted in the hydrolysis of several peptides, as revealed by reverse-phase HPLC profiles. Peaks 3, 5 and 6 showed the decreased area (%), whereas peaks 1, 2 and 4 showed the increased area. The GF-I fractions were found to be suitable for reducing bitterness in protein hydrolysates by catalyzing the hydrolysis of bitter peptides.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.47 no.6
• /
• pp.733-739
• /
• 2014

To develop an effective use for poor-quality individually quick-frozen (IQF) oysters Crassostrea gigas stored for a long period, the extract conditions, quality characteristics, and optimum reaction flavoring (RF) conditions of a complex extract from these IQF oysters were investigated. The moisture, pH, and volatile basic nitrogen contents of IQF oysters stored for 18 months (18M-IQFO) were 77.9%, 6.32, and 17.9 mg/100 g, respectively. Three different kinds of extract were prepared from 18M-IQFO: a hot-water extract (HE), scrap enzymatic hydrolysate (EH), and complex extract (CE). The respective extracts contained 5.5, 8.6, and 6.6% crude protein and 281.7, 366.0, and 343.0 mg/100 g amino nitrogen, and had 811, 359, and 1,170 mL/kg extraction yields. The CE was superior to the traditional HE in terms of the extraction yield, amino-nitrogen content, and organoleptic qualities, except for the odor. To improve flavor via the Maillard reaction, the reaction system used to produce a desirable flavor comprised CE (Brix $30^{\circ}$), 0.4 M glucose, 0.4 M glycine, and 0.4 M cysteine solution (4:2:1:1, v/v). The reaction time and pH were the independent variables, and the sensory scores for baked potato odor, masking shellfish odor, and boiled meat odor were the dependent variables. The surface response methodology (RSM) analysis of the multiple responses optimization gave a reaction time of 120.6 minutes and pH 7.33 at $120^{\circ}C$. The reaction improved the flavor of CE considerably, as compared to that of the unreacted extract.