Aflatoxin in raw peanut kernels marketed in Malaysia.

The occurrence of af latoxin in eighty-four samples of raw peanut kernels which are randomly collected from Malaysian super- markets was examined. Analysis for af latoxin was performed by solvent extraction and immunoaffinity clean-up followed by the determination using high performance liquid chromatography equipped with post-column photochemical reactor for enhanced detection and f luorescence detector. A detection limit of 0.01-0.09 ng/mL and a quantification limit of 0.04-0.30 ng/mL were obtained. The af latoxin concentrations ranged from not detected to 97.28 ng/g in all samples investigated. About 78.57% of the samples were contaminated with af latoxin, of which 10.71% exceeded the maximum tolerable limit of 15 ng/g set by the Codex. Average recoveries of the af latoxin analysis were acceptable which were in the range of 74.85 ± 8.83% for AFG2 at the concentration of 0.15 ng/mL and 103.91 ± 6.45% for AFB2 at the concentration of 0.15 ng/mL. The average daily intake estimated for total af la- toxins was 10.69 ng/kg body weight. There was a significant difference (P < 0.05) in af latoxin content between brands and locations

Soy sauce and its umami taste: a link from the past to current situation.

Soy sauce taste has become a focus of umami taste research. Umami taste is a 5th basic taste, which is associated to a palatable and pleasurable taste of food. Soy sauce has been used as an umami seasoning since the ancient time in Asia. The complex fermentation process occurred to soy beans, as the raw material in the soy sauce production, gives a distinct delicious taste. The recent investigation on Japanese and Indonesian soy sauces revealed that this taste is primarily due to umami components which have molecular weights lower than 500 Da. Free amino acids are the low molecular compounds that have an important role to the taste, in the presence of sodium salt. The intense umami taste found in the soy sauces may also be a result from the interaction between umami components and other tastants. Small peptides are also present, but have very low, almost undetected umami taste intensities investigated in their fractions

Antioxidant Activity of Skimmed Cow and Soy Milks Fermented by Lactic Isolates of Kefir Granules

Background and Objective: The proteolytic system of lactic acid bacteria hydrolyzes milk protein into several peptides, including those with antioxidative activities. The aim of this study was to assess antioxidant activities in cow and soy milks fermented by Lacticaseibacillus rhamnosus BD2, Lentilactobacillus kefiri YK4 and Lentilactobacillus kefiri JK17 previously isolated from kefir granules and their correlations with the peptide contents. Material and Methods: Reconstitutes of skimmed cow and soy milks were fermented by the highlighted isolates at 37 ℃ for 0, 24, 48 and 72 h. Fermented products were analyzed for the isolates, pH, total titratable acidity, antioxidant activity (% radical 2,2-diphenyl-1-picrylhydrazil inhibition and antioxidant capacity expressed in µg AAE.ml-1 whey) and total peptides. Fermented skimmed cow and soy milks with the highest antioxidant activity were then partially fractionated using molecular filters of 10 and 3 kDa. Fractions with the highest activity were analyzed further for peptide identification. Statistical analysis was carried out using one-way analysis of variance and Duncan multiple range tests (p≤0.05) using SPSS software v.16.0. Results and Conclusion: All isolates were able to grow in reconstituted skimmed cow and soy milks, while total count of reached to 9 log CFU.ml-1 with significant (p≤0.05) increases in titratable acidity and total peptides and decreased pH. Growth of the three isolates was mildly slower in soy milk than in skimmed cow milk. The maximum antioxidant activities were seen after 72-h fermentation of cow and soy milks. No differences were observed in antioxidant activity of cow milk fermented by the three isolates; however, Lacticaseibacillus rhamnosus BD2&nbsp;produced the highest antioxidant activity in soy milk. In general, increases in antioxidant activities correlated with increases in the peptide contents. Fraction of less than 3 kDa of the two milks fermented by Lacticaseibacillus rhamnosus BD2 showed the highest antioxidant activity. Analyses of peptides present in these fractions using high resolution LC-MS/MS and in silico identification of peptides with antioxidant activity have been reported in this study. The present study suggests that the three isolates can be used as starter cultures in fermenting cow and soy milks to increase their antioxidant activities. Peptides with molecular weight of less than 3 kDa play key roles in antioxidant activity. Conflict of interest: The authors declare no conflict of interest

Validasi Metode Analisis Kolesterol dalam Telur dengan HPLC-ELSD

A method using high-performance liquid chomatography (HPLC) coupled with an evaporative light-scattering detector (ELSD) for the determination of cholesterol in egg was validated. A silica column and a binary mixture of hexane and isopropanol (90:10) as a mobile phase were used to separate cholesterol. Cholesterol was detected at 1.5 min using cholesterol standard and HPLC-ELSD condition: evaporation temperature 50 ºC, air pressure 2.2 bars, and flow rate of mobile phase 2 mL/min. A method linearity for the cholesterol analysis in egg as a sample matrix was obtained at a range of 50 to 3000 µg/g sample, with R2&gt;0.990. Instrument detection limit and limit of quantitation were determined at 1.07 and 3.56 µg/mL, respectively. Recovery test results by spiking cholesterol standard in egg sample at low, medium, and high concentrations (50, 250 and 3000 µg/g ) were 122.13, 108.23, and 44.71%, respectively. Their corresponding repeatability values were 5.26, 4.29, and 10.11%. Method detection limit and intralab reproducibility (to analyze a sample) were observed at 2.30 µg/g and 0.04%. The method is valid for cholesterol analysis in egg at low and medium concentrations

Kajian Risiko Aflatoksin M1 dalam Produk Formula untuk Bayi dan Anak Usia 0-36 Bulan

Aflatoxin M1 (AFM1) is a carcinogenic compound found in milk-based products including infant and young children formula. The aim of this study was to determine the risk characterization of infants and young children to AFM1 through the consumption of formula products. For this purpose, the Estimated Daily Intake (EDI) for infants and young children was calculated by multiplying AFM1 concentration in 44 infant formulas, 53 advanced infant formulas, and 16 growing up formulas with consumption data. The concentration of AFM1 in these formula products were retrieved from food registration in Indonesian FDA from January 2015-June 2018. The average concentration of AFM1 in infant formula, advanced infant formulas, and growing up formula (lower bound-upper bound) were 0.0226-0.0335; 0.0418-0.0510; and 0.0038-0.0123 ng/g, respectively. The average EDI of AFM1 for infants and young children aged 0-6 months, 6-12 months, and 1-3 years based on individual consumption were 0.260-0.386, 0.282-0.343, 0.029-0.092 ng/kg body weight (BW)/day. The average EDI of AFM1 for infants and young children aged 0-6 months, 6-12 months, and 1-3 years based on the recommended consumption by food producer (lower bound-upper bound) were 0.403-0.598; 0.663-0.809; 0.031-0.098 ng/kgBW/day. The average hazard index (HI) values for infants aged 0-6 months and 6-12 months (lower bound-upper bound) were greater than 1 (one), i.e., 1.94-2.88 and 3.20-3.90, which indicates there is a health risk. However hazard index value for young children aged 1-3 years (lower bound-upper bound) were less than 1 (one), i.e., 0.15-0.47, which indicates a lower health risk. Keywords: advanced infant formula, aflatoxin M1, growing up formula, hazard index, infant formul

Modification of a gas chromatography-mass spectrometry method for the determination of acrylamide in fried snacks

Acrylamide is a toxic and probably carcinogenic compound and also neurotoxin in humans and animals that is formed naturally in certain foodstuffs, especially those rich in carbohydrate, during heat processing or cooking at high temperatures. This study was carried out to develop and validate the determination of acrylamide in fried snacks using gas chromatography-mass spectrometry (GCMS). The developed method involved the extraction of acrylamide with water followed by a cleanup treatment using Oasis HLB and MCX solid-phase extraction cartridges, bromination using reduced amount of saturated bromine water (from 15 to 2.5 ml due to bromine vapour is harmful and inhalation may be fatal as a result of spasm, inflammation, edema of the larynx and bronchi, also causes respiratory tract irritation with possible burns), then dehydrobromination by adding sodium thiosulfate solution until the yellow color has disappeared and using triethylamine to convert 2,3-dibromopropionamide to 2-bromopropenamide. This derivative is less polar compared to the acrylamide and is therefore easily soluble in non–polar organic solvents like ethyl acetate and hexane. The limit of detection (LOD) and limit of quantitation (LOD) of the method were 5 and 15 µg kg-1, respectively, and the regression coefficient was 0.9997. The recoveries of acrylamide in banana fritter samples at low, medium and high concentrations of 100, 200 and 4000 µg kg-1, respectively, were in the range of 84 to 109%. The repeatability and reproducibility values of the method ranged to 3-10 and 0.6–6, 0.3–8 for different days and different operators, respectively

Validasi Metode Analisis Kolesterol dalam Telur dengan HPLC-ELSD

A method using high-performance liquid chomatography (HPLC) coupled with an evaporative light-scattering detector (ELSD) for the determination of cholesterol in egg was validated. A silica column and a binary mixture of hexane and isopropanol (90:10) as a mobile phase were used to separate cholesterol. Cholesterol was detected at 1.5 min using cholesterol standard and HPLC-ELSD condition: evaporation temperature 50 ºC, air pressure 2.2 bars, and flow rate of mobile phase 2 mL/min. A method linearity for the cholesterol analysis in egg as a sample matrix was obtained at a range of 50 to 3000 µg/g sample, with R2&gt;0.990. Instrument detection limit and limit of quantitation were determined at 1.07 and 3.56 µg/mL, respectively. Recovery test results by spiking cholesterol standard in egg sample at low, medium, and high concentrations (50, 250 and 3000 µg/g ) were 122.13, 108.23, and 44.71%, respectively. Their corresponding repeatability values were 5.26, 4.29, and 10.11%. Method detection limit and intralab reproducibility (to analyze a sample) were observed at 2.30 µg/g and 0.04%. The method is valid for cholesterol analysis in egg at low and medium concentrations

Validasi Metode Analisis Kandungan Spesifik Residu Total Monomer Stiren Pada Kemasan Polistiren

Monomer stiren merupakan bahan dasar kemasan pangan yang menjadi isu perhatian terkait keamanan pangan. Saat ini di dalam peraturan nasional maupun internasional, peraturan persyaratan pada total residu dari monomer stiren dalam kemasan pangan. Dalam rangka menunjang pengawasan kemasan pangan polistiren, maka diperlukan peningkatan kapasitas pengujian kandungan spesifik residu total monomer stiren di laboratorium sesuai dengan peraturan yang berlaku. Penelitian ini bertujuan untuk melakukan validasi metode analisis pengujian kandungan spesifik residu total monomer stiren pada kemasan polistiren dengan heptana sebagai simulan pangan menggunakan kromatografi gas dengan pendeteksi ionisasi nyala, sesuai prosedur uji yang diatur dalam Peraturan Kepala Badan POM Nomor HK.03.1.23.07.11.6664 Tahun 2011 tentang Pengawasan Kemasan Pangan. Hasil validasi metode analisis adalah linieritas dengan persamaan regresi y = 0,186x nilai R2 = 0,999, presisi dengan nilai relatif standar deviasi (RSD) = 0,93 %, akurasi dengan persen perolehan kembali (% recovery) 98,04 ± 2,62 %, pada konsentrasi stiren yang ditambahkan 502 μg/g dan selektivitas yang baik.

Pojavnost gena koji reguliraju biosintezu folata u bakterijama mliječno-kiselog vrenja izoliranih iz različitih izvora

Research background. Lactic acid bacteria (LAB) are known to produce folate. However, this ability is highly strain-dependent. Folate synthesis in specific LAB strains is affected by the availability of folate, which can be consumed by other LAB under certain conditions. Moreover, differences in folate synthesis capabilities are related to the presence of folate biosynthesis-related genes and regulation of this pathway. Experimental approach. As basic information to better understand the regulation of folate biosynthesis among different LAB species and strains, folate biosynthetic genes were screened and identified in folate-producing and non-folate-producing LAB isolated from various local food sources in Indonesia. The extracellular folate productivity amounts of the isolates were analyzed using high-performance liquid chromatography with a diode array detector (HPLC-DAD). Results and conclusions. Eleven of the thirteen tested LAB isolates had all of the eight genes involved in folate biosynthesis (folE, folQ, folB, folK, folP, folC1, folA and folC2). Furthermore, these isolates produced extracellular folate ranging from 10.37 to 31.10 µg/mL. In contrast, two non-folate-producing isolates lacked several folate biosynthetic genes, such as folQ, folP and folA, which is possibly the reason for their inability to synthesize folate de novo. Phylogenetic tree construction revealed that the folate biosynthetic genes (excluding folK and folP) from six distinct species of folate-producing LAB isolates were monophyletic with homologous genes from other LAB species in the database. Novelty and scientific contribution. In this study, the distribution of folate biosynthetic genes in various LAB species was determined. The findings from this research support the use of folate biosynthesis marker genes in the genotypic screening for folate-producing LAB.Pozadina istraživanja. Bakterije mliječno-kiselog vrenja poznati su proizvođači folata, međutim, to svojstvo uvelike ovisi o njihovom soju. Na sintezu folata u pojedinim bakterijama mliječno-kiselog vrenja utječe dostupnost folata kojega bakterije konzumiraju pod određenim uvjetima. Osim toga, razlike u sposobnosti proizvodnje folata proizlaze iz prisutnosti gena koji reguliraju biosintezu tog vitamina. Eksperimentalni pristup. Radi što boljeg razumijevanja sposobnosti različitih bakterija mliječno-kiselog vrenja da reguliraju biosintezu folata, ispitana je pojavnost gena koji sudjeluju u regulaciji tog procesa u bakterijama koje proizvode folat i onima koje ga ne proizvode, izdvojenim iz različitih uzoraka hrane u Indoneziji. Izvanstanična proizvodnja folata ispitana je visokodjelotvornom tekućinskom kromatografijom sa detektorom s nizom dioda (HPLC-DAD). Rezultati i zaključci. Jedanaest od ukupno trinaest ispitanih bakterija mliječno-kiselog vrenja nosilo je svih osam gena uključenih u regulaciju biosinteze folata (folE, folQ, folB, folK, folP, folC1, folA i folC2). Osim toga, ti su izolati proizveli 10,37 do 31,10 μg/mL izvanstaničnog folata. Nasuprot tome, dvama sojevima bakterija koji ne proizvode folat nedostajalo je nekoliko gena za sintezu folata, kao što su folQ, folP i folA, što je vjerojatno razlog zašto ne mogu proizvesti folat de novo. Izradom filogenetskog stabla otkriveno je da geni koji reguliraju biosintezu folata (osim gena folK i folP), izolirani iz šest različitih sojeva mliječno-kiselih bakterija što proizvode folat, potječu od samo jednog pretka s genima homolognim s onima iz drugih vrsta bakterija mliječno-kiselog vrenja navedenih u bazi podataka. Novina i znanstveni doprinos. U ovom je radu utvrđena raspodjela gena odgovornih za sintezu folata u različitim bakterijama mliječno-kiselog vrenja. Dobiveni rezultati potvrđuju mogućnost korištenja genetičkih markera biosinteze folata pri ispitivanju genotipske specifičnosti bakterija mliječno-kiselog vrenja koje proizvode taj vitamin

Role of carboxypeptidases to the free amino acid composition, methylpyrazine formation and sensory characteristic of under- fermented cocoa beans

The role of carboxypeptidases B (from porcine) and Y (from baker's yeast), applied to under-fermented cocoa beans, on the formation of cocoa-specific aroma precursors, the aroma and sensory quality after roasting was investigated. The application of carboxypeptidases in under-fermented cocoa beans was to overcome the slaty and purple beans with an excessive taste of their bitterness and astringency after roasting, and the lack of cocoa-specific aroma attribute. The 5% carboxypeptidases B and Y were applied separately on the dry-powdered under-fermented cocoa beans at several incubation periods (6, 12, 24, 48 h). The levels of free amino acids, especially hydrophobic amino acids as essential cocoa aroma precursors, were significantly higher in cocoa beans treated with carboxypeptidase B as compared to the control. This led to the higher levels of 2,5-dimethyl-, 2,3,5-trimethyl- and 2,3,5,6-tetramethylpyrazines found in the samples after roasting at 150°C for 15 min. Therefore, carboxypeptidase B was more efficient for the formation of the cocoa-specific aroma compared to carboxypeptidase Y. However, both carboxypeptidase treatments had no significant effect (p>0.05) on flavor attributes of cocoa liquors made from the roasted cocoa beans, eventhough there is a significant correlation between the formation of hydrophobic free amino acids with cocoa-specific flavor attribute and between the methylpyrazines with the flavor attribute (r2 = 0.91 - 0.99)