Songklanakarin Journal of Science and Technology (SJST) 

About: Songklanakarin Journal of Science and Technology (SJST) is an academic journal. The journal publishes majorly in the area(s): Lactic acid & Shrimp. Over the lifetime, 229 publications have been published receiving 4752 citations.

The use of the stable free radical diphenylpicrylhydrazyl (dpph) for estimating antioxidant activity

Abstract: Molyneux, P. The use of the stable free radical diphenylpicrylhydrazyl (DPPH) for estimating antioxidant activity

Fatty acids composition of 10 microalgal species

Abstract: Pratoomyot, J., Srivilas, P. and Noiraksar, T. Fatty acids composition of 10 microalgal species

Antimicrobial activities of essential oils and crude extracts from tropical Citrus spp. against food-related microorganisms

Abstract: Ethyl acetate extracts and hydrodistillated-essential oils from peels of Citrus spp. were investigated for their antimicrobial activities against food related microorganisms by broth microdilution assay. Overall, ethyl acetate extracts from all citrus peels showed stronger antimicrobial activities than their essential oils obtained from hydrodistillation. The ethyl acetate extract of kaffir lime (Citrus hystrix DC.) peel showed broad spectrum of inhibition against all Gram-positive bacteria, yeast and molds including Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Saccharomyces cerevisiae var. sake and Aspergillus fumigatus TISTR 3180. It exhibited minimum inhibitory concentration (MIC) values of 0.28 and 0.56 mg/ml against Sac. cerevisiae var. sake and B. cereus, respectively while the minimum bactericidal concentration (MBC) values against both microbes were 0.56 mg/ml. The MIC values of the extract against L. monocytogenes, A. fumigatus TISTR 3180 and S. aureus were 1.13 mg/ml while the MBC values against L. monocytogenes as well as A. fumigatus TISTR 3180 and S. aureus were 2.25 and 1.13 mg/ml, respectively. The major components of the ethyl acetate extract from kaffir lime were limonene (31.64 %), citronellal (25.96 %) and β-pinene (6.83 %) whereas β-pinene (30.48 %), sabinene (22.75 %) and citronellal (15.66 %) appeared to be major compounds of the essential oil obtained from hydrodistillation.

Casein micelle structure: a concise review

Abstract: Phadungath, C. Casein micelle structure: a concise review Songklanakarin J. Sci. Technol., 2005, 27(1) : 201-212 Milk is a complex biological fluid with high amount of proteins, lipid and minerals. The function of milk is to supply nutrients such as essential amino acids required for the growth of the newborn. In addition, due to the importance of casein and casein micelles for the functional behavior of dairy products, the nature and structure of casein micelles have been studied extensively. However, the exact structure of casein micelles is still under debate. Various models for casein micelle structure have been proposed. Most of the proposed models fall into three general categories, which are: coat-core, subunit (sub-micelles), and internal structure models. The coat-core models, proposed by Waugh and Nobel in 1965, Payens in 1966, Parry and Carroll in 1969, and Paquin and co-workers in 1987, describe the micelle as an aggregate of caseins with outer layer differing in composition form the interior, and the structure of the inner part is not accurately identified. The sub-micelle models, proposed by Morr in 1967, Slattery and Evard in 1973, Schmidt in 1980, Walstra in 1984, and Ono and Obata in 1989, is considered to be composed of roughly spherical uniform subunits. The last models, the internal structure models, which were proposed by Rose in 1969, Garnier and RibadeauDumas in 1970, Holt in 1992, and Horne in 1998, specify the mode of aggregation of the different caseins.

Review: Lipid and myoglobin oxidations in muscle foods

Abstract: Lipid oxidation and myoglobin oxidation in muscle foods occur in a concurrent manner and each process appears to enhance the other. During oxidation of oxymyoglobin, both superoxide anion and hydrogen peroxide are produced and further react with iron to produce hydroxyl radical. The hydroxyl radical has the ability to penetrate into the hydrophobic lipid region and hence facilitates lipid oxidation. The prooxidant effect of oxymyoglobin on lipid oxidation is concentrationdependent. At equimolar concentrations, oxymyoglobin shows higher prooxidative activity towards lipid than metmyoglobin. However, the catalytic activity of metmyoglobin is promoted by hydrogen peroxide. The reaction between hydrogen peroxide and metmyoglobin results in the formation of two active hypervalent myoglobin species, perferrylmyoglobin and ferrylmyoglobin, which are responsible for lipid oxidation. Additionally, lipid oxidation results in a wide range of aldehyde products, which are reported to induce the oxidation of oxymyoglobin. Metmyoglobin formation is generally greater in the presence of unsaturated aldehydes than their saturated counterparts of equivalent carbon chain length. In addition, increasing chain length of aldehydes, from hexenal through nonenal, results in the increased metmyoglobin formation. Moreover, aldehydes alter myoglobin redox stability by increasing oxymyoglobin oxidation, decreasing the metmyoglobin reduction via enzymatic process, and enhance the prooxidant activity of metmyoglobin. Therefore, the oxidation of both lipid and myoglobin directly affect the quality and acceptability of muscle foods and the lowering of such a phenomenon can enhance the shelf-life stability of those foods.