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Food Preservatives (food + preservative)
Selected AbstractsESSENTIAL OIL AND OLEORESINS OF CINNAMOMUM TAMALA (TEJPAT) AS NATURAL FOOD PRESERVATIVES FOR PINEAPPLE FRUIT JUICEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 5 2008I.P.S. KAPOOR ABSTRACT The essential oil and oleoresins (methanol, ethanol, isooctane and CCl4) from tejpat have been used as a natural food preservative for pineapple juice. The stored samples were studied for pH, total and reducing sugars, ascorbic acid, peroxide value, titrable acidity and microbiological count at fixed time intervals of 7 days. Significant changes were observed during the storage period. The essential oil showed better preservative effect than the oleoresins did. PRACTICAL APPLICATIONS Essential oils and oleoresins derived from spices are considered luxurious items because of their uses in aromatherapy, confectionary, beverages and pharmaceutical industries. Moreover, they also possess antioxidant and antimicrobial efficiency. Essential oil and oleoresins extracted from tejpat are used in the preservation of pineapple juice, which is better and safer than synthetic conservers. This characteristic is of great interest for the food industries. [source] Nisin-resistant (Nisr) Listeria monocytogenes and Nisr Clostridium botulinum Are Not Resistant to Common Food PreservativesJOURNAL OF FOOD SCIENCE, Issue 5 2000A.S. MAZZOTTA ABSTRACT Nisin-resistant (Nisr) strains of Clostridium botulinum and Listeria monocytogenes may arise as nisin becomes more widely used as an additional safety barrier in minimally-processed foods. The sensitivity of Nisr L. monocytogenes ATCC 700301 and ATCC 700302 and toxigenic Nisr C. botulinum 169B to low pH, salt, sodium nitrite, and potassium sorbate was assayed using discontinuous gradients in broth and compared to the parental wild-type strains. The nisin-resistant strains did not have intrinsic resistance to low pH, sodium chloride, potassium sorbate, or sodium nitrite. In no case were the Nisr L. monocytogenes and C. botulinum strains examined more resistant to inhibitors than the parental strains. [source] Lantibiotics: structure, biosynthesis and mode of actionFEMS MICROBIOLOGY REVIEWS, Issue 3 2001Olivia McAuliffe Abstract The lantibiotics are a group of ribosomally synthesised, post-translationally modified peptides containing unusual amino acids, such as dehydrated and lanthionine residues. This group of bacteriocins has attracted much attention in recent years due to the success of the well characterised lantibiotic, nisin, as a food preservative. Numerous other lantibiotics have since been identified and can be divided into two groups on the basis of their structures, designated type-A and type-B. To date, many of these lantibiotics have undergone extensive characterisation resulting in an advanced understanding of them at both the structural and mechanistic level. This review outlines some of the more recent developments in the biochemistry, genetics and mechanism of action of these peptides. [source] ESSENTIAL OIL AND OLEORESINS OF CINNAMOMUM TAMALA (TEJPAT) AS NATURAL FOOD PRESERVATIVES FOR PINEAPPLE FRUIT JUICEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 5 2008I.P.S. KAPOOR ABSTRACT The essential oil and oleoresins (methanol, ethanol, isooctane and CCl4) from tejpat have been used as a natural food preservative for pineapple juice. The stored samples were studied for pH, total and reducing sugars, ascorbic acid, peroxide value, titrable acidity and microbiological count at fixed time intervals of 7 days. Significant changes were observed during the storage period. The essential oil showed better preservative effect than the oleoresins did. PRACTICAL APPLICATIONS Essential oils and oleoresins derived from spices are considered luxurious items because of their uses in aromatherapy, confectionary, beverages and pharmaceutical industries. Moreover, they also possess antioxidant and antimicrobial efficiency. Essential oil and oleoresins extracted from tejpat are used in the preservation of pineapple juice, which is better and safer than synthetic conservers. This characteristic is of great interest for the food industries. [source] Analyses of preservatives by capillary electrochromatography using methacrylate ester-based monolithic columnsELECTROPHORESIS, Issue 18-19 2004Hsi-Ya Huang Abstract Five common food preservatives were analyzed by capillary electrochromatography, utilizing a methacrylate ester-based monolithic capillary as separation column. In order to optimize the separation of these preservatives, the effects of the pore size of the polymeric stationary phase, the pH and composition of the mobile phase on separation were examined. For all analytes, it was found that an increase in pore size caused a reduction in retention time. However, separation performances were greatly improved in monolithic columns with smaller pore sizes. The pH of the mobile phase had little influence on separation resolution, but a dramatic effect on the amount of sample that was needed to be electrokinetically injected into the monolithic column. In addition, the retention behaviors of these analytes were strongly influenced by the level of acetonitrile in the mobile phase. An optimal separation of the five preservatives was obtained within 7.0 min with a pH 3.0 mobile phase composed of phosphate buffer and acetonitrile 35:65 v/v. Finally, preservatives in real commercial products, including cold syrup, lotion, wine, and soy sauces, were successfully determined by the methacrylate ester-based polymeric monolithic column under this optimized condition. [source] Identification of the agent from Lactobacillus plantarum KFRI464 that enhances bacteriocin production by Leuconostoc citreum GJ7JOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007J.Y. Chang Abstract Aim:, To provide evidence that the production of bacteriocin by lactic acid bacteria can be enhanced by the presence of a bacteriocin-sensitive strain and identify the agent that is responsible for enhancing bacteriocin production. Methods and Results:, One bacteriocin-producing lactic acid bacterium was isolated from kimchi. The strain GJ7 was designated as Leuconostoc citreum GJ7 based on Gram staining, biochemical properties, and 16S rRNA gene sequencing. The isolate produced a heat- and pH-stable bacteriocin (kimchicin GJ7), which has antagonistic activity against a broad spectrum of micro-organisms. Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified kimchicin GJ7 showed a single band of molecular weight c. 3500 Da. Cultures of Leuc. citreum GJ7 in the presence of thermally inactivated kimchicin GJ7-sensitive strains, Lactobacillus plantarum KFRI 464, Lactobacillus delbrueckii KFRI 347, or Leuconostoc mesenteroides KCTC 1628, increased bacteriocin production. This inducing factor was characterized and purified from Lact. plantarum KFRI 464, which showed the greatest enhancement of kimchicin GJ7 activity. The inducing factor was purified using a DEAE (diethyl aminoethyl)-Sephacel column and high-performance liquid chromatography, and yielded a single band of c. 6500 Da. N -terminal sequencing of the inducing factor identified 16 amino acids. The N -terminal sequence of the inducing factor was synthesized and examined for the induction of kimchicin GJ7 activity, and was found to induce activity, but at a level about 10% lower than that of the entire molecule. Conclusions:, The presence of a bacteriocin-sensitive strain, Lact. plantarum KFRI 464, acts as an environmental stimulus to activate the production of kimchicin GJ7 by Leuc. citreum GJ7. The inducing factor from Lact. plantarum KFRI 464 is highly homologous to the 30S ribosomal protein S16 from various micro-organisms. The N -terminal sequence of the inducing factor examined in this study is a very important sequence related to the inducing activity. Nevertheless, the inducing factor may not be part of the ribosomal protein S16 itself. Significance and Impact of the Study:, We believe that the present study is the first to identify an agent that is produced by one micro-organism and influences bacteriocin production in another. The bacteriocin-enhancing system described in this study could be effectively used to control the growth of other micro-organisms (sensitive cells) in food systems. Moreover, this enhancement of bacteriocin production can be applied usefully in industrial production of natural food preservatives. [source] Fungal metabolism of butter and shea oils by Penicillium roquefortii in solid state culturesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2004Qin-Tao Liu Abstract Monoacylglycerols (monoglycerides, MAGs) were produced from butter oil and shea stearin fraction (shea oil) by two strains of Penicillium roquefortii, FRR 2456 (isolated from a spoilt melon) and Wisbey PJ (a commercial dairy strain), at pH 7.0 at 10 and 25 °C. The system was designed as a model of cheese using modified Czapek medium in solid state cultures. Shea oil with its unique fatty acid profile (stearic, oleic and palmitic acids) was used for comparison with butter oil. Yields of MAGs, which ranged from 3 to 14 g kg,1 oil, were higher with butter than with shea oil and higher when the spoilage strain FRR 2456 was used. Monoacylglycerols produced by mycelium-bound lipases from both fungal strains were mainly sn -1(3) or , isomers (60,70 mol%). Monopalmitin was the major MAG produced from both butter and shea oils. The production and use of MAGs alone or in combination with free fatty acids (FFAs) as food preservatives are discussed. It is implied that sn -1(3) MAGs together with free fatty acids may be part of a natural antimicrobial system in relatively high-pH foods such as blue mould-ripened cheese where growth of foodborne pathogens such as Listeria monocytogenes can be a problem. Copyright © 2003 Society of Chemical Industry [source] |