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1.
J. Karovičová Milan Drdák Gabriel Greif Eva Hybenová 《European Food Research and Technology》1999,210(1):53-56
The reasons for using lactic acid bacteria are to make food durable, to improve its taste and to maintain the nutritive,
physiological and hygienic value of the fermentation products. Sixteen strains of the genus Lactobacillus were tested on samples of white fresh cabbage and of a sterilized cabbage and carrot juice mixture. After 7 days of lactic
acid fermentation at 27 °C or 30 °C, reducing sugars, total acidity, pH value, lactic, citric and acetic acids, ammonia,
nitrates and nitrites were measured in the samples. On the basis of the criteria mentioned above three strains were acceptable.
These strains reduced the content of nitrates in the original samples.
Received: 14 December 1998 / Revised version: 18 March 1999 相似文献
2.
The ability of Lactobacillus plantarum ATCC 8014 to inhibit Clostridium botulinum toxin production in pea soup was investigated. Soup containing C. botulinum spores (103/g) with and without L. plantarum (106/g) were evaluated. Soup containing only type A spores was toxic on days 1 and 2 when incubated at 35°C and 25°C, respectively. Soup containing only proteolytic type B spores was toxic on days 2 and 5 at 35°C and 25°C, respectively. Soup containing only type E spores was toxic at 25°C, 15°C, and 5°C in 7, 7, and 63 days respectively. No toxin was found in soup containing C. botulinum spores plus L. plantarum at any temperature studied. 相似文献
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Mende S Krzyzanowski L Weber J Jaros D Rohm H 《Journal of Bioscience and Bioengineering》2012,113(2):185-191
Some Lactobacillus delbrueckii ssp. bulgaricus strains are able to synthesize exopolysaccharides (EPS) and are therefore highly important for the dairy industry as starter cultures. The aim of this study was to investigate the nutritional requirements for growth and EPS production of Lactobacillus delbrueckii ssp. bulgaricus DSM 20081. A medium was developed from a semi-defined medium (SDM) in which glucose was replaced by lactose and different combinations of supplements (nucleobases, vitamins, salts, sodium formate and orotic acid) were added. Constant pH batch fermentation with the modified medium resulted in an EPS yield of approximately 210 mg glucose equivalents per liter medium. This was a 10-fold increase over flask cultivation of this strain in SDM. Although not affecting cell growth, the mixture of salts enhanced the EPS synthesis. Whereas EPS production was approximately 12 mg/g dry biomass without salt supplementation, a significantly higher yield (approximately 20 mg/g dry biomass) was observed after adding the salt mixture. In continuous fermentation, a maximal EPS concentration was obtained at a dilution rate of 0.31/h (80 mg EPS/L), which corresponded to a specific EPS production of 49 mg/g dry biomass. 相似文献
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Irene Pagana Ruben Morawicki Tiffany J. Hager 《International Journal of Food Science & Technology》2014,49(2):641-649
Organic waste generated from industrial sweet potato canning is estimated to be 30% of incoming raw material with significant residual carbohydrate content. The purpose of this study was to evaluate the potential of waste generated from sweet potato processing material to support the growth of lactic acid bacteria and the production of lactic acid. The waste was comprised of 16.5% solids consisting of 18.5% ash, 4.4% protein, 20.5% simple sugars and 19% soluble starch. Following a screening of three lactic acid bacteria strains, Lactobacillus rhamnosus was deemed the best candidate for lactic acid production. The potential of various dilutions of the enzyme‐hydrolysed waste, with and without pH control, as a fermentation substrate was evaluated. Lactic acid production was highest in hydrolysed waste (without dilution) at pH set point 5.0, yielding 10 g L?1 in 72 h. Thus, lactic acid, a valuable organic compound, can be generated from sweet potato waste. 相似文献
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Sorayya Azarnia Daniel St-Gelais Claude P. Champagne Kieran N. Kilcawley 《Food Biotechnology》2013,27(2):135-149
The use of recombinant aminopeptidase (PepN) from Lactobacillus rhamnosus S93 in free or encapsulated form was investigated to shorten the duration of Cheddar cheese ripening. Proteolysis was determined by measuring the soluble nitrogen as phosphotungstic acid (PTA-N) derivatives and free amino acids (FAA) over a 6-month period. The experimental cheeses received higher scores for sensory properties than the control cheese. The amounts of PTA-N and total FAA in the cheese with the encapsulated enzyme after 2 months of ripening were close to those of the control cheese after 6 months, suggesting the acceleration in proteolysis by about 4 months. 相似文献