Contribution of Composition, Physicochemical Characteristics and Polyphosphates to the Microbial Safety of Pasteurized Cheese Spreads

1994 ◽  
Vol 57 (4) ◽  
pp. 295-300 ◽  
Author(s):  
KARL F. ECKNER ◽  
WENDY A. DUSTMAN ◽  
ANNA A. RYŚ-RODRIGUEZ
Keyword(s):  
Clostridium Botulinum ◽  
Toxin Production ◽  
Physicochemical Characteristics ◽  
The Other ◽  
Microbial Safety ◽  
Processed Cheese ◽  
Moisture Contents ◽  
Glass Containers ◽  
Different Types ◽  
Process Cheese

Pasteurized process cheese spread was manufactured with moisture contents of 52, 54, 56 and 60%. Three different types of phosphate emulsifier were used, disodium ortho-phosphate and two commercially-available polyphosphates, S9 and S9H. Pasteurized, processed cheese spreads were inoculated with approximately 1 × 104 Clostridium botulinum spores/gram cheese in the cook kettle, held 3 min at 80°C, hot-filled into glass containers, and incubated at 30°C. Samples were analyzed over 30 weeks for growth of C. botulinum and toxigenesis. Toxin was first detected in 60% moisture cheese with disodium ortho-phosphate as the emulsifier at 8 weeks and in 60% moisture cheese with the test polyphosphates as the emulsifier when tested at 20 weeks. None of the other cheese formulations were toxic at 20 weeks. Toxin production correlated statistically to time, moisture, pH and phosphate type.

Antibotulinal Activity of Process Cheese Ingredients

2004 ◽  
Vol 67 (8) ◽  
pp. 1765-1769 ◽  
Author(s):  
KATHLEEN A. GLASS ◽  
ERIC A. JOHNSON
Keyword(s):  
Whey Protein ◽  
Clostridium Botulinum ◽  
Antimicrobial Effect ◽  
Toxin Production ◽  
Whey Protein Concentrate ◽  
Protein Concentrate ◽  
Fat Replacer ◽  
Blue Cheese ◽  
Sweet Whey ◽  
Process Cheese

Ingredients used in the manufacture of reduced-fat process cheese products were screened for their ability to inhibit growth of Clostridium botulinum serotypes A and B in media. Reinforced clostridial medium (RCM) supplemented with 0,0.5, 1, 2, 3, 5, or 10% (wt/vol) of various ingredients, including a carbohydrate-based fat replacer, an enzyme-modified cheese (EMC) derived from a Blue cheese, sweet whey, modified whey protein, or whey protein concentrate, did not inhibit botulinal growth and toxin production when stored at 30°C for 1 week. In contrast, RCM supplemented with 10% soy-based flavor enhancer, 10% Parmesan EMC, or 5 or 10% Cheddar EMC inhibited botulinal toxin production in media for at least 6 weeks of storage at 30°C. Subsequent trials revealed that the antibotulinal effect varied significantly among 13 lots of EMC and that the antimicrobial effect was not correlated with the pH or water activity of the EMC.

Antibotulinal Effectiveness of Nisin in Pasteurized Process Cheese Spreads

1987 ◽  
Vol 50 (10) ◽  
pp. 842-848 ◽  
Author(s):  
EILEEN B. SOMERS ◽  
STEVE L. TAYLOR
Keyword(s):  
Sodium Chloride ◽  
Clostridium Botulinum ◽  
Toxin Production ◽  
Disodium Phosphate ◽  
Process Cheese

Pasteurized process cheese spreads were prepared at moisture levels ranging from 52 to 57% with added sodium chloride at levels from 0 to 2.0%, with disodium phosphate levels ranging from 1.4 to 2.5%, and with nisin levels of 0 to 250 ppm. Clostridium botulinum spores were added at a level of approximately 1000 spores per gram of cheese spread except for control batches and one experiment where the spore levels were varied (10–1000 spores/g). The cheese spreads were incubated at 30°C for up to 48 weeks. Nisin is an effective antibotulinal agent in pasteurized process cheese spreads. Addition of nisin allows formulation of pasteurized process cheese spreads with reduced sodium levels (addition of 1.4% disodium phosphate and no added sodium chloride) or slightly higher moisture levels (55–57%) by comparison to typical commercial pasteurized process cheese spreads. Higher levels of nisin (100 and 250 ppm) were required to prevent outgrowth of botulinal spores in cheese spreads with highest moisture levels or most greatly reduced sodium levels. However, in a cheese spread of 52% moisture prepared with 2.5% disodium phosphate but no added sodium chloride, a nisin level of 12.5 ppm was able to prevent completely outgrowth and toxin production by C. botulinum.

Inhibition of Clostridium botulinum in Model Reduced-Sodium Pasteurized Prepared Cheese Products

2017 ◽  
Vol 80 (9) ◽  
pp. 1478-1488 ◽  
Author(s):  
Kathleen A. Glass ◽  
Ming Mu ◽  
Brian LeVine ◽  
Frank Rossi
Keyword(s):  
Clostridium Botulinum ◽  
Sorbic Acid ◽  
Interactive Effect ◽  
Stable Process ◽  
Toxin Production ◽  
Mouse Bioassay ◽  
Linear Quadratic ◽  
Cheese Products ◽  
Potassium Replacement ◽  
Process Cheese

ABSTRACT The 1986 Food Research Institute–Tanaka et al. model predicts the safety of shelf-stable process cheese spread formulations using the parameters of moisture, pH, NaCl, and disodium phosphate (DSP) to inhibit toxin production by Clostridium botulinum. Although this model is very reliable for predicting safety for standard-of-identity spreads, the effects of additional factors have not been considered. The objective of this study was to create a predictive model to include the interactive effect of moisture, pH, fat, sorbic acid, and potassium-based replacements for NaCl and DSP to reflect modern reduced-sodium recipes. Eighty formulations were identified using a central composite design targeting seven factors: 50 to 60% moisture, pH 5.4 to 6.2, 0 to 0.2% sorbic acid, 10 to 30% fat, 1.7 to 2.4% NaCl, 0.8 to 1.6% DSP, and 0 to 50% potassium replacement for sodium salts. Samples were inoculated with proteolytic C. botulinum spores at 3 log spores per g, hot filled into sterile vials, and stored anaerobically at 27°C. Samples were assayed at 0, 1, 2, 3, 4, 8.5, 17.5, 26, and 40 weeks for the presence of botulinum toxin using the mouse bioassay. A parametric survival model was fit to the censored time-to-toxin data. All linear, quadratic, and pairwise effects were considered for model fit. As hypothesized, the effects of pH, sorbate, moisture, DSP, and NaCl were highly significant (P < 0.001). Fat concentration and potassium replacement effects were significant at P < 0.021 and P < 0.057, respectively. The model consistently predicted the safety failure of the toxic samples, but it also predicted failure for some samples that were not toxic. This model is an adjunct to existing models by adding the factors of potassium salts, fat, and sorbic acid to predict the botulinal safety of prepared process cheese products but is not intended to be a substitute for formulation evaluation by a competent process authority.

Evaluation of Factors Involved in Antibotulinal Properties of Pasteurized Process Cheese Spreads

1986 ◽  
Vol 49 (7) ◽  
pp. 526-531 ◽  
Author(s):  
N. TANAKA ◽  
E. TRAISMAN ◽  
P. PLANTINGA ◽  
L. FINN ◽  
W. FLOM ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Water Activity ◽  
Clostridium Botulinum ◽  
Toxin Production ◽  
Inhibitory Effect ◽  
Low Ph ◽  
Disodium Phosphate ◽  
Minimum Number ◽  
Process Cheese ◽  
Design Experiments

Pasteurized process cheese spreads with various levels of sodium chloride, disodium phosphate, moisture and pH were challenged with spores of Clostridium botulinum types A and B. Response surface methodology was used to design experiments that would yield maximum results with the minimum number of trials. Supplemental experiments were added to further clarify the response and to examine combinations of special interest. A total of 304 treatment combinations (batches) was incubated at 30°C, and five samples from each batch were taken at predetermined intervals up to 42 wk of incubation and tested for botulinal toxin. Sodium chloride and disodium phosphate inhibited botulinal toxin production with similar effectiveness. The inhibitory effect of low pH (<5.7) and low moisture (<54%) levels on botulinal toxin production was as expected, i.e., as either pH or moisture went up, it was necessary to increase sodium chloride and/or phosphate concentrations to compensate. Differences in water activity between cheese spreads with different compositions were observed but they were too small to use for controlling the properties of the products, e.g., a range of 9% in moisture level (51 to 60%) produced only 0.022 variation in water activity. Combinations of the above factors were developed for safe pasteurized process cheese spreads containing up to 60% moisture.

Toxin Production by Clostridium botulinum in Shelf-Stable Pasteurized Process Cheese Spreads

1979 ◽  
Vol 42 (10) ◽  
pp. 784-786 ◽  
Author(s):  
D. A. KAUTTER ◽  
T. LILLY ◽  
R. K. LYNT ◽  
H. M. SOLOMON
Keyword(s):  
Water Activity ◽  
Drug Administration ◽  
Clostridium Botulinum ◽  
Toxin Production ◽  
Good Manufacturing Practice ◽  
Type B ◽  
Blue Cheese ◽  
Canned Foods ◽  
Shelf Stable ◽  
Process Cheese

Five non-refrigerated, pasteurized process cheese spreads, considered shelf-stable, were studied for their ability to support growth and toxin production by spores of Clostridium botulinum types A and B. Based on pH and water activity (aw) Cheese with Bacon, Limburger, Cheese Whiz, Old English, and Roka Blue cheese spreads were selected for the study. The pH ranged from 5.05 to 6.32 and the aw from 0.930 to 0.953. Fifty jars of each cheese spread were inoculated with 24,000 spores each; an additional 50 jars of the Cheese with Bacon spread received 460 spores each. The inoculum consisted of five type A and five type B strains in 0.1 ml of 0.85% NaCl. At 35 C, 46 jars of Limburger and 48 jars of Cheese with Bacon spread, which received the greater inoculum, became toxic starting at 83 and 50 days, respectively. One jar of Cheese with Bacon spread which received 460 spores became toxic. The average toxicity of the Limburger was 3000 MLD/ml of extract as compared with 54 MLD/ml for the Cheese with Bacon spread. Results of this study will be considered in determining whether these cheese spread products should be treated as low-acid canned foods under the Good Manufacturing Practice Regulations of the Food and Drug Administration.

scholarly journals Clostridium botulinum Type A Growth and Toxin Production in Media and Process Cheese Spread

1983 ◽  
Vol 45 (3) ◽  
pp. 1150-1152 ◽  
Author(s):  
Jorge Briozzo ◽  
Ethel Amato de Lagarde ◽  
Jorge Chirife ◽  
José L. Parada
Keyword(s):  
Clostridium Botulinum ◽  
Type A ◽  
Toxin Production ◽  
Botulinum Type ◽  
Process Cheese

Innovatory role of nanomaterials as bio-tools for treatment of cancer

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Khuram Shahzad Ahmad ◽  
Muntaha Talat ◽  
Shaan Bibi Jaffri ◽  
Neelofer Shaheen
Keyword(s):  
Cancer Treatment ◽  
Cancer Therapeutics ◽  
Physicochemical Characteristics ◽  
Global Scale ◽  
Current Review ◽  
Anti Cancer ◽  
Different Types ◽  
Cancerous Cells

AbstractConventional treatment modes like chemotherapy, thermal and radiations aimed at cancerous cells eradication are marked by destruction pointing the employment of nanomaterials as sustainable and auspicious materials for saving human lives. Cancer has been deemed as the second leading cause of death on a global scale. Nanomaterials employment in cancer treatment is based on the utilization of their inherent physicochemical characteristics in addition to their modification for using as nano-carriers and nano-vehicles eluted with anti-cancer drugs. Current work has reviewed the significant role of different types of nanomaterials in cancer therapeutics and diagnostics in a systematic way. Compilation of review has been done by analyzing voluminous investigations employing ERIC, MEDLINE, NHS Evidence and Web of Science databases. Search engines used were Google scholar, Jstore and PubMed. Current review is suggestive of the remarkable performance of nanomaterials making them candidates for cancer treatment for substitution of destructive treatment modes through investigation of their physicochemical characteristics, utilization outputs and long term impacts in patients.

Comparative Surface Imaging Study of Multifocal Diffractive Intraocular Lenses

2021 ◽  
Author(s):  
Hyeck Soo Son ◽  
Jung Min Lee ◽  
Ramin Khoramnia ◽  
Chul Young Choi
Keyword(s):  
Imaging Study ◽  
The Other ◽  
Intraocular Lenses ◽  
Optical Surface ◽  
Diffractive Optic ◽  
Atomic Force ◽  
Acceptable Range ◽  
Different Types ◽  
Concentric Pattern

Abstract Purpose To analyse and compare the surface topography and roughness of three different types of diffractive multifocal IOLs. Methods Using scanning electron microscope (SEM, Inspect F, 5.0 KV, maximum magnification up to 20,000) and atomic force microscope (AFM, Park Systems, XE-100, non-contact, area profile comparison, 10 × 10 µm, 40 × 40 µm), the surface quality of the following diffractive IOLs was studied: the AcrySof IQ PanOptix (Alcon, USA), the AT LARA 829MP (Carl Zeiss Meditec, Germany), and Tecnis Symfony (Johnson&Johnson Vision, USA). The measurements were made over three representative areas (central non-diffractive optic, central diffractive optic, and diffractive step) of each IOL. Roughness profile in terms of mean arithmetic roughness (Ra) and root-mean-squared roughness (Rq) values were obtained and compared statistically. Results In SEM examination, all IOLs showed a smooth optical surface without any irregularities at low magnification. At higher magnification, Tecnis Symfony showed unique highly regular, concentric, and lineate structures in the diffractive optic area which could not be seen in the other studied diffractive IOLs. The differences in the measured Ra and Rq values of the Tecnis Symfony were statistically significant compared to the other models (p < 0.05). Conclusion Various different topographical traits were observed in three diffractive multifocal IOLs. The Ra values of all studied IOLs were within an acceptable range. Tecnis Symfony showed statistically significant higher surface Ra values at both central diffractive optic and diffractive step areas. Furthermore, compared to its counterparts, Tecnis Symfony demonstrated highly ordered, concentric pattern in its diffractive surfaces.

Effect of Salt Level and Nitrite on Toxin Production by Clostridium botulinum Type E Spores in Smoked Great Lakes Whitefish1

1987 ◽  
Vol 50 (3) ◽  
pp. 212-217 ◽  
Author(s):  
S. L. CUPPETT ◽  
J. I. GRAY ◽  
J. J. PESTKA ◽  
A. M. BOOREN ◽  
J. F. PRICE ◽  
...  
Keyword(s):  
Great Lakes ◽  
Water Activity ◽  
Salt Concentration ◽  
Clostridium Botulinum ◽  
Toxin Production ◽  
Water Phase ◽  
Salt Level ◽  
Botulinum Type ◽  
Clostridium Botulinum Type E ◽  
Average Water

The effect of salt level and nitrite on botulinal safety of smoked whitefish was investigated. An average water-phase (wp) salt concentration of 4.4% inhibited outgrowth of Clostridium botulinum type E spores (103 spores/g) for over 35 d in temperature-abused (27°C) smoked whitefish. Incorporation of nitrite (220 mg/kg) during brining to the smoked salted (4.4%, wp) whitefish inhibited toxin production for 56 d at 27°C. An average salt concentration of 6.2% (wp), with or without nitrite, totally inhibited toxin production for the duration of the study (83 d). The effect of pH and water activity in temperature-abused smoked whitefish as a means of controlling toxin production by C. botulinum type E spores was evaluated.

RADIATION EXPOSURE TO THE BACK WITH DIFFERENT TYPES OF APRONS

2021 ◽  
Author(s):  
Seung Wan Hong ◽  
Tae Won Kim ◽  
Jae Hun Kim
Keyword(s):  
Radiation Exposure ◽  
Effective Dose ◽  
Exposure Time ◽  
The Other ◽  
Lead Apron ◽  
Type Group ◽  
Air Kerma ◽  
Different Types ◽  
The Relationship

Abstract Physicians and nurses stand with their back towards the C-arm fluoroscope when using the computer, taking things out of closets and preparing drugs for injection or instruments for intervention. This study was conducted to investigate the relationship between the type of lead apron and radiation exposure to the backs of physicians and nurses while using C-arm fluoroscopy. We compared radiation exposure to the back in the three groups: no lead apron (group C), front coverage type (group F) and wrap-around type (group W). The other wrap-around type apron was put on the bed instead of on a patient. We ran C-arm fluoroscopy 40 times for each measurement. We collected the air kerma (AK), exposure time (ET) and effective dose (ED) of the bedside table, upper part and lower part of apron. We measured these variables 30 times for each location. In group F, ED of the upper part was the highest (p &lt; 0.001). ED of the lower part in group C and F was higher than that in group W (p = 0.012). The radiation exposure with a front coverage type apron is higher than that of the wrap-around type and even no apron at the neck or thyroid. For reducing radiation exposure to the back of physician or nurse, the wrap-around type apron is recommended. This type of apron can reduce radiation to the back when the physician turns away from the patient or C-arm fluoroscopy.

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