Time filter

Source Type

Nakano M.,Toyo Institute of Food Technology
Biocontrol Science | Year: 2015

The thermophilic spore forming bacteria Geobacillus stearothermophilus is recognized as a major cause of spoilage in canned food. A quantitative real-time PCR assay was developed to specifically detect and quantify the species G. stearothermophilus in samples from canned food. The selected primer pairs amplified a 163-bp fragment of the 16S rRNA gene in a specific PCR assay with a detection limit of 12.5 fg of pure culture DNA, corresponding to DNA extracted from approximately 0.7 CFU/mL of G. stearothermophilus. Analysis showed that the bacterial species G. stearothermophilus was not detected in any canned food sample. Our approach presented here will be useful for tracking or quantifying species G. stearotethermophilus in canned food and ingredients. Source

Nakano M.,Toyo Institute of Food Technology
Journal of Food Protection | Year: 2015

A quantitative real-time PCR assay was developed to specifically detect and quantify Moorella thermoacetica and/or Moorella thermoautotrophica from canned coffee beverages. Six different combinations of newly designed primers were examined, and primer pair v1-1F/v4R was found to specifically amplify M. thermoacetica and M. thermoautotrophica. The minimum detection sensitivity was 15 fg of pure culture DNA from M. thermoacetica. Twenty commercial canned coffee beverages were then screened for the presence of M. thermoacetica, and two were shown to contain >1.3 and >1.0 CFU/ml, respectively. Therefore, the assay developed in this study may be useful for accurately tracking and quantifying M. thermoacetica and M. thermoautotrophica in beverage samples. Copyright ©, International Association for Food Protection. Source

Takeuchi Y.,Toyo Institute of Food Technology | Takeuchi Y.,Toyo Seikan Kaisha Ltd. | Takahashi H.,Toyo Institute of Food Technology
Nippon Suisan Gakkaishi (Japanese Edition) | Year: 2013

Grass prawn tissue is softened by retort sterilization. It was speculated that the cause of the softening was gelatinization of the collagen by the drip which flowed out of the shrimp during retort sterilization. By the pretreatment of boiling in NaCl solution before retort sterilization, the moisture content in the shrimp decreased and the drip in the pouch decreased during retort sterilization. Moreover, setting up a headspace in the pouch prevented contact between shrimp muscles and the drip. The results showed that the texture was improved when gelatinization was suppressed. Source

Takeuchi Y.,Toyo Institute of Food Technology | Takahashi H.,Toyo Institute of Food Technology
Nippon Suisan Gakkaishi (Japanese Edition) | Year: 2011

The change of tissue strength in prawn by heat treatment (boil, retort (121°C, F0=6)) was studied. The physical and chemical properties of prawn after heat treatment were measured by X-ray computerized tomography (CT), scanning electron microscopy (SEM) and environmental scanning electron microscopy (ESEM), and chemical analysis for percentage of gelatin in collagen. According to the results of the strength of muscular tissue, the retorted sample was the softest. By measurement of X-ray CT, the muscle density of the retorted sample was lower than that of the boiled sample. The muscle fibers of raw and boiled samples were wrapped by connective tissue, but the retorted sample was partially-removed was viewed under ESEM. The gelatinization rate of collagen in the retorted sample was higher than that of the boiled one. It is suggested that the softness of prawn tissue by sterilization is caused by gelatinization of collagen. Source

Isshiki A.,Corporate Research and Development Toyo Seikan Group Holdings Ltd. | Takeharu H.,1 70 Yako | Aoki S.,Toyo Institute of Food Technology | Kokaji M.,1 70 Yako | And 3 more authors.
Biocontrol Science | Year: 2014

We offer the first description of the development of a multiple detection technique for fungi by DNA microarray with the simultaneous use of internal transcribed spacer region (ITS) of ribosomal RNA gene and β-tubulin gene probes. The assay uses 12 oligonucleotide probes and multiplex amplification to detect fungal species belonging to various sections of Aspergillus, the Eurotium genus, and the Penicillium genus. The specificity of each probe was tested using 231 reference fungal strains, including 79 target and 152 non-target strains in 102 species of 24 genera. We determined the optimum concentration of the primer pairs for multiplex PCR to be 0.5 μM for the β-tubulin gene and 0.125 μM for the ITS region. In the field trial using 76 specimens containing 323 fungi (up to five fungal strains were included in one specimen), the concordance rate between the DNA microarray and the DNA sequencing results was 97.4% at the species or genus levels. Source

Discover hidden collaborations