Effects of enzyme concentration, temperature, pH and time on the degree of hydrolysis of protein extract from viscera of tuna (Euthynnus affinis) by using alcalase

Protein from viscera of tuna was extracted by using water at ratio of viscera to water of 1:1 (w/v) and freeze-dried. The protein was found to be high in glycine (9.6%), arginine (9.2%), alanine (7.0%), lysine (7.2%) and leucine (7.0%). A study was then carried out to determine the effect of alcalase concentration, temperature, pH and incubation time on degree of hydrolysis (DH) during hydrolysis by using single factor experiment. The hydrolysis of viscera protein extract (VPE) was carried out at concentrations of 1.0, 1.5 and 2.0%. The DH of hydrolysates was significantly (p<0.05) increased when enzyme concentration was increased from 1.0% to 1.5% but became constant at concentration exceeding 1.5%. An enzyme concentration at 1.5% was subsequently used in the study of the effect of the other parameters. It was found that the value of the DH also increased when the temperature was increased from 30 to 40°C. However, the hydrolysis at higher temperature (60°C) produced lower DH. Prolonging the time of incubation from 60 min up to 240 min significantly (p< 0.05) increased the DH. As for pH, there were no significant effects observed

Penilaian Kualitas Fisika Dan Kimia Gelatin Ekstrak Dari Kaki Ayam Tua (Kat)

This study aims to examine the physico chemical properties of gelatin extracted from spent hen with HCl pretreatment with immersion for 5 and 10 days. With extraction stages E1 temperature (45°C), E2 (65°C), and E3 75°C. Analysis results show there is significant difference (p<0.05) on the strength of bloom, the attribute color (b*has a negative value), and solubility. Respective is in the range ash content 1,10-2,26%, protein (68.91-79.86%), fat (1:10 to 2:26%), moisture (5.0-10.3%) and carbohydrate (10.1-20.84% ) for SCF 5, while the SCF 10. Ash (1.99-2.27%), protein (77.81-80.80%), fat (1:00 to 2:00%), moisture (5.0-7.0%), carbohydrate (9.58-12.60%)

Volatile compounds and lactic acid bacteria in spontaneous fermented sourdough

The aim of this study is to identify the predominating lactic acid bacteria (LAB) in a spontaneous fermented wheat sourdough. At the same time, an investigation towards volatile compounds that were produced was also carried out. Lactobacillus plantarum has been identified as the dominant species of lactobacilli with characters of a facultative heterofermentative strain. The generated volatile compounds that were produced during spontaneous fermentation were isolated by solvent extraction method, analysed by gas chromatography (GC), and identified by mass spectrophotometer (MS). Butyric acid has been found to be the main volatile compound with relative abundance of 6.75% and acetic acid at relative abundance of 3.60%. Esters that were formed at relatively low amount were butyl formate (1.23%) and cis 3 hexenyl propionate (0.05%). Butanol was also found at low amount with relative abundance of 0.60%. The carbohydrate metabolism of Lactobacillus plantarum may contributed to the production of acetic acid in this study via further catabolism activity on lactic acid that was produced. However, butyric acid was not the major product via fermentation by LAB but mostly carried out by the genus Clostridium via carbohydrate metabolism which needs further investigatio

Aktiviti antioksida dan warna mufin daripada sisa puri pitaya merah (Hylocereus polyrhizus) (Antioxidant activity and colour of red pitaya puree muffin (Hilosereus polirhizus))

Sisa puri pitaya merah bersama biji telah digunakan dalam penyediaan mufin yang dicampurkan dengan 10%, 15% dan 20% puri dalam formulasi bater. Ujian warna, kandungan jumlah polifenol, jumlah flavonoid, ujian antioksida; pemerangkapan radikal bebas 2,2-difenil-1-pikrilhidrazil (DPPH) dan ujian penurunan ferrik (FRAP) telah dijalankan. Warna bater 3 jenis mufin tersebut berwarna merah jambu violet. Warna merah jambu (nilai a) meningkat dengan signifikan (p<0.05) selaras peningkatan peratus kandungan puri manakala kecerahan (nilai L) menurun dengan peningkatan puri. Apabila dimasak, semua warna merah jambu daripada bater hilang. Permukaan mufin adalah lebih gelap (nilai L), dengan mufin 20% puri paling signifikan (p<0.05). Isi kesemua mufin berwarna kuning dan kecerahan (nilai L) didapati berkurang secara signifikan (p<0.05) dengan pertambahan peratus puri. Jumlah polifenol sampel mufin menunjukkan mufin 10% puri pitaya ekstrak air mengandungi jumlah polifenol yang paling tinggi (29.0 mg GAE/100 g sampel). Kandungan flavonoid menunjukkan mufin 20% puri pitaya mengandungi flavonoid yang paling signifikan (p<0.05) 15.3 mg katekin/100 g sampel berbanding mufin kawalan 11.0 mg katekin. Bagi ujian antioksida DPPH, semua mufin dengan puri pitaya menunjukkan peratus pemerangkapan yang lebih baik berbanding kawalan. Ujian FRAP menunjukkan pola yang serupa dengan keputusan mufin 10% (17.4), mufin 15% (15.4) dan mufin 20% (17.5 mg trolox/100 g sampel). Warna merah jambu bater mufin hilang semasa proses memasak namun nilai antioksida masih diperolehi dalam mufin masa

Process development for the production of protein hydrolysate from cockle (Anadara granosa) meat wash water

A study was carried out to determine the process parameters and optimization for the hydrolysis of protein precipitate from cockle (Anadara granosa) meat wash water. Precipitation of the protein in the wash water was done using pH manipulation (pH3-8). The precipitate was hydrolyzed using hydrochloric acid (HCl) and optimized for HCl volume, HCl concentration and hydrolysis time using response surface methodology (RSM) based on a central composite rotatable design. Based on the results, hydrolysis of cockle meat wash water precipitate was carried out by precipitation of the wash water at pH4. Optimum condition for the hydrolysis of 2.0 g of cockle meat wash water precipitate was 25 mL of 1 N HCl for 10 h which resulted in nitrogen content (NC) of 0.7% and degree of hydrolysis (DH) of 55%. NC and DH were significantly influenced only by the hydrolysis time

Optimization of extraction parameters of total phenolic compounds from Henna (Lawsonia inermis) Leaves

Response surface methodology (RSM) in conjunction with central composite rotatable design (CCRD) was performed in the present study to optimize the extraction parameters for assessing maximum yield of total phenolic content (TPC) from henna (Lawsonia inermis) leaves. The range of the independent variables, namely acetone concentration (20-90%, v/v), extraction time (10-90 minutes) and extraction temperature (25-45°C) were identified by a first set of single factor experiments. The actual values of the independent variables coded at five levels were selected based on the results of single factor experiments. The optimum conditions for extraction of TPC were found to be at acetone concentration 48.07%, extraction time 73.78 minutes and extraction temperature 39.57°C. Under these optimized conditions, the experimental maximum yield of TPC was 7203.74 mg GAE/100g DW, which was in close agreement with predicted values, thus indicating the suitability of the models developed and the success of RSM in optimizing the extraction conditions