Simultaneous Enumeration of the Characteristic Microorganisms in Yogurt Using the Hydrophobic Grid Membrane Filter System

1990 ◽  
Vol 53 (1) ◽  
pp. 64-66 ◽  
Author(s):  
GEORGE E. MILLARD ◽  
ROBIN C. MCKELLAR ◽  
RICHARD A. HOLLEY
Keyword(s):  
Membrane Filter ◽  
Streptococcus Thermophilus ◽  
Membrane System ◽  
Lactobacillus Bulgaricus ◽  
Excellent Correlation ◽  
Light Blue ◽  
Single Plate ◽  
Dark Blue ◽  
International Dairy Federation

Utilization of the hydrophobic grid membrane system (HGMF) in conjunction with erioglaucine-supplemented tryptone-phytone-yeast extract (TPYE) agar permitted the differential enumeration of Streptococcus thermophilus and Lactobacillus bulgaricus in yogurt. An anaerobic incubation of 42°C resulted in conditions under which streptococcal colonies were light blue and the lactobacillus colonies were a distinct dark blue. Excellent correlation was achieved when the above method was compared with the International Dairy Federation Standard 117:1983 by coincident analysis of 12 commercial yogurts. The method allowed a reliable single plate determination of cocci to rod ratios from 20:1 to 1:5.

A novel method for the determination of linting propensity of paper

TAPPI Journal ◽  
2012 ◽  
Vol 11 (10) ◽  
pp. 9-17
Author(s):  
ALESSANDRA GERLI ◽  
LEENDERT C. EIGENBROOD
Keyword(s):  
Ash Content ◽  
The Novel ◽  
Offset Printing ◽  
Excellent Correlation ◽  
End Conditions ◽  
Bottom Side ◽  
Novel Method ◽  
Total Fraction

A novel method was developed for the determination of linting propensity of paper based on printing with an IGT printability tester and image analysis of the printed strips. On average, the total fraction of the surface removed as lint during printing is 0.01%-0.1%. This value is lower than those reported in most laboratory printing tests, and more representative of commercial offset printing applications. Newsprint paper produced on a roll/blade former machine was evaluated for linting propensity using the novel method and also printed on a commercial coldset offset press. Laboratory and commercial printing results matched well, showing that linting was higher for the bottom side of paper than for the top side, and that linting could be reduced on both sides by application of a dry-strength additive. In a second case study, varying wet-end conditions were used on a hybrid former machine to produce four paper reels, with the goal of matching the low linting propensity of the paper produced on a machine with gap former configuration. We found that the retention program, by improving fiber fines retention, substantially reduced the linting propensity of the paper produced on the hybrid former machine. The papers were also printed on a commercial coldset offset press. An excellent correlation was found between the total lint area removed from the bottom side of the paper samples during laboratory printing and lint collected on halftone areas of the first upper printing unit after 45000 copies. Finally, the method was applied to determine the linting propensity of highly filled supercalendered paper produced on a hybrid former machine. In this case, the linting propensity of the bottom side of paper correlated with its ash content.

scholarly journals Aceitação sensorial e caracterização de frozen yogurt de leite de cabra com adição de cultura probiótica e prebiótico

2009 ◽  
Vol 39 (9) ◽  
pp. 2595-2600 ◽  
Author(s):  
Larissa de Lima Alves ◽  
Neila Silvia Pereira dos Santos Richards ◽  
Larissa Vargas Becker ◽  
Diego Fontana de Andrade ◽  
Liana Inês Guidolin Milani ◽  
...  
Keyword(s):  
Lactobacillus Acidophilus ◽  
Streptococcus Thermophilus ◽  
Lactobacillus Bulgaricus ◽  
Bifidobacterium Animalis ◽  
Frozen Yogurt

O leite de cabra é recomendado para pessoas intolerantes ao leite de vaca e/ou portadoras de desordens gastrintestinais. frozen yogurt elaborado a partir de iogurte de leite de cabra foi acrescido de 1% de prebiótico (inulina), 0,25% de cultura starter (Streptococcus thermophilus e Lactobacillus bulgaricus) e 0,25% de cultura probiótica (Bifidobacterium animalis e Lactobacillus acidophilus) para verificar seu potencial probiótico (após sete e 120 dias de armazenamento), sua qualidade físico-química e sua aceitação sensorial. Durante a estocagem, houve redução de células viáveis da flora microbiana, principalmente dos probióticos. Ainda assim, o produto apresenta potencialidade probiótica pela soma de B. animalis e L. acidophilus atingir o mínimo desejável até o fim do armazenamento. Os valores de extrato seco total (26,6±0,2%), proteína (3,0±0,2), gordura (2,6±0,1%), pH (5,5±0,01) e ácido láctico (0,2±0,01%) encontram-se semelhantes aos relatados em outros trabalhos para o mesmo produto. A avaliação sensorial foi realizada por 50 provadores não treinados em teste com escala hedônica de sete níveis e intenção de compra. O produto recebeu bons escores para aparência global, cor, aroma e sabor; já textura e sabor residual obtiveram menores índices de aceitação. Na intenção de compra, 61% dos avaliadores declararam que comprariam o produto, contra 39% que não comprariam. Nessas condições, demonstra-se a viabilidade de elaboração de frozen yogurt de leite caprino acrescido de pre- e probióticos.

Estimation of bacterial production in fresh waters by the simultaneous measurement of [35S]Sulphate and D-[3H]glucose uptake in the dark

1978 ◽  
Vol 24 (8) ◽  
pp. 939-946 ◽  
Author(s):  
P. G. C. Campbell ◽  
J. H. Baker
Keyword(s):  
Bacterial Production ◽  
Membrane Filter ◽  
Outer Edge ◽  
Size Fractionation ◽  
Sulphate Uptake ◽  
Uptake Rates ◽  
Chalk Stream ◽  
Glucose Assimilation ◽  
Heterotrophic Production

Sulphate uptake in the dark by phytoplankton constitutes a severe limitation to the determination of bacterial heterotrophic production from sulphate-uptake rates. Consequently a modification to the 35S-method has been developed involving size fractionation to separate the algae from the bacteria. Both the whole water sample and the algae-free filtrate are incubated in the dark with trace quantities of [3H]glucose, whereas the filtrate alone is incubated with 35SO4. The experimental determined ratio (whole sample glucose assimilation: filtrate glucose assimilation) is used to correct the measured sulphate uptake (filtrate) and yields an estimate of bacterial sulphate uptake in the whole sample.A potential filtration artefact has been demonstrated in the 35SO4 uptake methodology. Excision of the outer edge of the membrane filter and counting of the inner wetted circle alone eliminated this problem and significantly improved the analytical performance of the method: coefficient of variation ~ 5%, detection limit ~ 2 ng S ℓ−1 h−1. The modified [35SO4]–[3H]-glucose method was applied to samples from an English chalk stream: bacterial sulphate uptake was higher during the spring diatom maximum (10.6 ng S ℓ−1 h−1) than 3 weeks later when detritus dominated the seston (4.9 ng S ℓ−1 h−1). We estimate the corresponding rates of formation of particulate (bacterial) carbon to be 0.53 and 0.24 μg C ℓ−1 h−1 respectively.

Windmill Hill, Avebury, and Grime's Graves Cores and Choppers

1919 ◽  
Vol 3 (1) ◽  
pp. 104-108
Author(s):  
H. G. O. Kendall
Keyword(s):  
The Other ◽  
Light Blue ◽  
Number Of Species ◽  
The One ◽  
Dark Blue

Cores and chopping tools are very numerous at Windmill Hill, Avebury Down, Grime's Graves, and Cissbury. They are characteristic of the industry. In the main they differ markedly from the cores of the prism industries. True prisms are rare in the one and numerous in the other; the one shows comparatively broad, the other comparatively narrow facets and flakes; the flakes of the latter being on the whole thinner and finer. It is noteworthy that when the flints of both industries have lain near the surface, those of the one in Herts., Wilts., Sussex, Norfolk, and Suffolk are almost invariably white or light blue; whilst those of the other range from light blue, through dark blue, to unchanged black or grey; with a partial exception, easy of explanation, on the coast of Cornwall.The “lumps” may be divided into a number of species. Some were cores only, others were tools for chopping, cutting, scraping, pecking, boring, or clearing out split marrow bones; some were cores first and tools afterwards.

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