摘要:

A total of 575 packages of frozen blanched vegetables representing 17 products packed in 24 factories located in 12 states were examined for numbers and kinds of coliforms. The organisms were recovered from over 90% of the samples with the average counts of total coliforms being over 100 per g. Thirty‐seven percent were positive for fecal coliforms (FC) using a 44.5°C incubation, with all products except broccoli yielding an average count of less than 50 per g. Escherichia coli was recovered from only 29% of the FC‐positive samples. Other species which were responsible for a positive fecal coliform test were Klebsiella pneum oniae, Enterobacter cloacae, E. agglomerans, E. aerogenes, and Citrobacter freundii. Incubation at 45.5°C eliminated only C. freundii. Fecal coliforms in vegetables negative for E. coli may be the result of raw vegetable transmission to processing equipment followed by culture development and transfer to foods being proc

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1980.tb00386.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

A limited survey was carried out to determine the nitrosamine content of several varieties of alcoholic beverages (beer and ale, whiskey, wine, cider, etc.) sold in Canada. Of 22 samples of different beers and ales analyzed all but one contained traces of dimethylnitrosamine; the overall mean level found was 1.5 ppb. Only one Canadian rye and one Scotch whiskey out of a total of 13 samples contained traces of either dimethylnitrosamine or diethylnitrosamine. All the 8 wines and 7 cider samples were negative.

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1980.tb00387.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Effects of various doses of α‐chaconine were examined in the central nervous system by electrophysiological tests and by determining levels of several neurotransmitters. Assays of acetylcholine, norepinephrine, dopamine, serotonin, and the serotonin metabolite, 5‐hydroxyindoleacetic acid, failed to show significant trends following intraperitoneal injections of up to 20 mg/kg α‐chaconine. Symptoms observed at relatively low doses (8 or 10 mg/kg) included sedation, respiratory impairment, and constriction of abdominal muscles. At the same dosage the electroencephalogram pattern showed a significant increase in the proportion of low‐frequency activity. Tachycardia was observed at both low (10 mg/kg) and high doses (40 mg/kg), whereas intermediate doses (20 or 30 mg/kg) were associated with bradycardia. Unchanged acetylcholine levels after α‐chaconine administration did not correlate with previous reports of brain cholinesterase inhibition produced by

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1980.tb00388.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Investigations were performed to avoid cross‐reactions in the enzyme linked immunosorbent assay, using the sandwich technique, for detection of Staphylococcus aureus enterotoxin type B. Non‐specific reactions can be caused by cross‐reacting antigens and by Protein A, produced by S. aureus. The former reactions can be prevented by adsorption with culture filtrate of non‐toxin type B producing strains. The latter reaction is caused by the binding of Protein A to the Fc fragments of the IgG antibodies. Interference by Protein A was completely eliminated by using the F(ab')2fragments of the IgG antibodies.ELISA experiments in which these purified F(ab')2fragments were used resulted in a highly specific detection of entertoxin type B, both in culture filtrates and i

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1980.tb00389.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY

摘要:

Domestic and imported cheeses were studied to determine the incidence of mycotoxin producing molds. The total incidence of molds in visibly non‐moldy cheese was very low. Isolation of molds from plate counts, and directly from samples, showed that the major portion of the flora was made up of Penicillium species; 86% in domestic cheeses and 80% in imported cheeses. Many of the Penicillium isolates were capable of growing at low storage temperatures. Mold counts done at 5°C, and prolonged storage of cheese samples at 5°C indicated a potential for considerable mold growth on cheese during refrigerated storage. While the overall incidence of known mycotoxin producing molds was low, a number of potentialy toxic species were found, including P. cyclopium, P. viridicatum, A. flavus and A. ochraceus. These species accounted for 4.4% of all the isolates from domestic cheeses and 4.0% from imported cheeses. Screening of all mold isolates for production of several known mycotoxins showed that a number of isolates (14.1% of all molds in domestic cheeses and 11.5% in imported cheeses) were capable of producing certain mycotoxins including patulin, penicillic acid, ochratoxin A, citrinin and aflatox

ISSN:0149-6085    

DOI:10.1111/j.1745-4565.1980.tb00390.x

出版商:Blackwell Publishing Ltd    

年代:1980

数据来源: WILEY