Survival of inoculate Escherichia coli O157:H7 and Listeria monocytogenes in soymilk mixtures during fermentation and refrigerated storage

The objectives of the experiment were: (1) to prepare a soymilk mixture that could be fermented by a select type of starter culture to produce an acceptable level of lactic acid at 37 or 43%deg;C within 7 hr, (2) to measure pH and acid levels of the soymilk mixtures during fermentation for 7 hr and during storage for 72 hr at 4°C and (3) to enumerate the counts of inoculated Echerichia coli O157:H7 and Listeria monocytogenes to determine their survival in the soymilk during fermentation and storage. A soymilk mixture was prepared with water, soy flour (8.63%, w/v) and sugar (7.0%, w/v) and fermented with starter cultures YC-180 (Streptococcus thermophilus and Lactobacillus bulgaricus) or a combination of YC-180 and NU-A (Lactobacillus acidophilus) at 37 or 43°C for 7 hr. The total solids content of the water and soy flour mixture was 7.67%. These conditions comprised four treatments. The fermented soymilk mixture was placed in storage at 4°C and held for 72 hr. In Part I, during fermentation and storage, pH and total acidity (% lactic acid) were measured on each of the four treatments on each hour during fermentation and on 24-hr cycles during storage. In Part II, four treatments as described above were inoculated with starter cultures, fermented and stored; however, E. coli O157:H7 or L. monocytogenes were added at the time the starter culture was added. Treatments in Part II were tested for pH and acidity and enumerated for CFU/g for the respective pathogenic bacteria and starter cultures. In Part I, after 7 hr fermentation, pH (3.93) was lowest and acidity (1.02%) was highest for treatment 43-3 (43°C, YC-180 and NU-A starter cultures with 3 bacteria), and pH was highest (4.32) and acidity was lowest (0.63%) for treatment 37-2 (37°C, YC-180 culture with 2 bacteria). The pH and acid concentration did not change during storage. In Part 11, with E. coli O157:H7 or L monocytogenes, pH and acidity levels at the end of the fermentation period were similar to those in Part 1, with no changes occurring during storage. The correlation coefficient between pH and acidity over the fermentation period was always \u3e -0.99. Survival of E. coli O157:H7 was affected by all the experimental variables. At 4 hr of fermentation, a decline in the population occurred among the treatments. As fermentation continued, survival of E. coli O157:H7 in all treatments except 37-2 decreased rapidly. In treatment 43-3, counts were non-detectable (\u3c log 2 CFU/g) at 5 hr. In treatment 43-2, counts were non-detectable at 7 hr, and in treatment 37-3, counts were non-detectable after 24 hr of storage at 4°C. After 72 hr of storage of treatment 37-2, the mean count had decreased from log 7 CFU/g to log 5 CFU/g. Correlation coefficients between the mean pH values and the mean CFU/g and between the mean acidity values and the mean CFU/g over the fermentation period were 0.6952 and -0.8177, respectively. Survival of L. monocytogenes was affected by all the experimental variables. By 4 hr of fermentation, changes began to appear in the population of the pathogen. After 7 hr of fermentation, the mean count for treatment 43-3 had decreased to log 2 CFU/g; survival in the other treatments was higher. In storage, the counts for treatment 43-3 decreased to non-detectable by 24 hr. Counts in the other treatments after 72 hr of storage were log 4.0 CFU/g or higher. Correlation coefficients between the mean pH values and the mean CFU/g and between the mean acidity values and the mean CFU/g during fermentation were 0.5850 and -0.7266, respectively. In general, fermentation of soymilk mixtures at 43°C produced lower pH and higher concentration of lactic acid and was more effective in destroying both of the pathogenic bacteria than fermentation at 37°C. Addition of L. acidophilus to the inoculum caused greater destruction of the pathogenic bacteria than inoculum without L. acidophilus. E. coli O157:H7 was less able to survive under the conditions in the fermenting soymilk mixture than L. monocytogenes

Thermal Properties of Banana Starch Nanocrystals Prepared by Acid Hydrolysis as Reinforcing Filler

Banana is one of the most important tropical fruits in Thailand. It is available throughout the year, i.e., no specific growing season, resulting to the low cost. All parts of banana plant can be used, particularly its fruit has several adaptable in term of how to eat it. However, banana is ripe and perishable easily. Therefore, it is a potential resource that can be utilized and developed in order to add more value to this raw material. In this work, green banana fruits were used as a raw material for preparing a starch nanocrystal reinforcing filler in bio-nanocomposites. The green banana was extracted into banana starch by using 0.05 N sodium hydroxide solution. The composition of the obtained banana starch contained 90.61% of starch, 18.82% of amylose, 0.19% of protein, 0.11% of ash, and 0.03% of lipid. The banana starch composition exhibited low content of protein, ash, and lipid (&lt;0.5%) indicating that the obtained banana starch was pure enough to be used. After that, starch nanocrystal (SNC) was prepared from banana starch by acid hydrolysis with 3.5 M sulfuric acid and 3.0 M hydrochloric acid at 40°C for 7 and 5 hours, repectively. The obtained banana SNC showed an increase in the degree of crystallinity from 28.03% for native banana starch to 47.13% and 40.15% for banana SNC prepared from sulfuric and hydrochloric acid hydrolysis, respectively. Furthermore, the thermal properties of banana SNC were investigated by differential scanning calorimeter (DSC) and thermogravimetric analyzer (TGA) in order to assess thermal stability of banana SNC for using as reinforcing filler in bio-nanocomposite. The decomposition temperature of native banana starch and SNC was in the range of 260-315°C. The gelatinization temperature of banana SNC increased as a result of the increment of its degree of crystallinity when comparing with native starch.</jats:p

Characteristics of Microwave-Esterified Cellulose Film from Corn Husk and Cotton: Effects of Degree of Substitution

The modified cellulose film was synthesized from corn husk and waste cotton fabrics in LiCl/DMAc solvent system by esterification reaction under microwave energy using lauroyl chloride and DMAP as an esterifying agent and a catalyst, respectively. By varying microwave power and reaction time used in the esterification reaction, modified cellulose powder with various degree of substitution (DS) was obtained. The structure of modified cellulose was proved by FT-IR and 1H-NMR analysis. The DS value of modified cellulose was measured by 1H-NMR. The modified cellulose films with different DS values were prepared by casting method. The influences of DS values on the properties of the prepared modified cellulose films were tested for their wettability, water absorption, gloss, and tensile properties. The results showed significant effect of the cellulose source and the DS values on the properties of modified cellulose film. The modified cellulose from corn husk resulted in the film with greater tensile strength and elongation at break than the film from waste cotton fabrics. The esteried-cellulose from both sources with high DS values yielded the film with higher tensile properties and lower water absorption.</jats:p

Factors affecting quality development and certification of local fishery products in Ranong Province, Thailand

The purpose of this study was to determine the factors affecting the quality development and certification of local fishery products in Thailand. The study was cross-sectional and survey method was used to collect the data. We distributed 325 questionnaires to processors of fishery products working in Ranong province. PLS-SEM was used to test the proposed hypotheses. The findings of the study indicate that supply chain had a significant relationship with product quality and certification. The findings also indicate that government regulations moderate the relationship between supply chain and product quality and certification. The current study will discuss the Thai government’s policies and efforts to ensure the quality and safety of aquaculture products from “Pond to Plate” through an efficient management strategy.</jats:p

Relationship between knowledge management and foreign tacit knowledge on multinational pharmaceutical product innovation

Multinational companies face various challenges regarding knowledge transfer, relationship harmony and environmental challenges which can diverse the operational performance of companies with globalized disturbed customers. This research paper applies a model with aims to find the impact of foreign tacit knowledge (FTK) on the product innovation of multinational pharmaceutical firms in Thailand. The model of this research also consists of knowledge exchange, ICT competence, and relationship harmony as mediating variables to evaluate the relationship between FTK and product innovation levels of multinational pharmaceutical firms. For data analysis and calculation, some significant techniques were used such as KMO, SEM and descriptive statistics. Furthermore, the results and discussions illustrate that the foreign tacit knowledge has a positive influence on pharmaceutical product innovation which further enhances the performance of the firms. Similarly, ICT competence, and relationship harmony have a positive mediating role in the relationship between tacit knowledge and product innovation while knowledge exchange has a insignificant mediating role. The findings of this research study have many managerial as well as practical implications. From a managerial point of view, this study helps managers of multinational companies to identify the impact of FTK on overall and product performance

Relationship between knowledge management and foreign tacit knowledge on multinational pharmaceutical product innovation

Multinational companies face various challenges regarding knowledge transfer, relationship harmony and environmental challenges which can diverse the operational performance of companies with globalized disturbed customers. This research paper applies a model with aims to find the impact of foreign tacit knowledge (FTK) on the product innovation of multinational pharmaceutical firms in Thailand. The model of this research also consists of knowledge exchange, ICT competence, and relationship harmony as mediating variables to evaluate the relationship between FTK and product innovation levels of multinational pharmaceutical firms. For data analysis and calculation, some significant techniques were used such as KMO, SEM and descriptive statistics. Furthermore, the results and discussions illustrate that the foreign tacit knowledge has a positive influence on pharmaceutical product innovation which further enhances the performance of the firms. Similarly, ICT competence, and relationship harmony have a positive mediating role in the relationship between tacit knowledge and product innovation while knowledge exchange has a insignificant mediating role. The findings of this research study have many managerial as well as practical implications. From a managerial point of view, this study helps managers of multinational companies to identify the impact of FTK on overall and product performance.</jats:p

Factors affecting quality development and certification of local fishery products in Ranong Province, Thailand

The purpose of this study was to determine the factors affecting the quality development and certification of local fishery products in Thailand. The study was cross-sectional and survey method was used to collect the data. We distributed 325 questionnaires to processors of fishery products working in Ranong province. PLS-SEM was used to test the proposed hypotheses. The findings of the study indicate that supply chain had a significant relationship with product quality and certification. The findings also indicate that government regulations moderate the relationship between supply chain and product quality and certification. The current study will discuss the Thai government’s policies and efforts to ensure the quality and safety of aquaculture products from “Pond to Plate” through an efficient management strategy.</jats:p

Factors affecting quality development and certification of local fishery products in Ranong Province, Thailand

The purpose of this study was to determine the factors affecting the quality development and certification of local fishery products in Thailand. The study was cross-sectional and survey method was used to collect the data. We distributed 325 questionnaires to processors of fishery products working in Ranong province. PLS-SEM was used to test the proposed hypotheses. The findings of the study indicate that supply chain had a significant relationship with product quality and certification. The findings also indicate that government regulations moderate the relationship between supply chain and product quality and certification. The current study will discuss the Thai government’s policies and efforts to ensure the quality and safety of aquaculture products from “Pond to Plate” through an efficient management strategy

Factors Affecting Quality Development and Certification of Local Fishery Products in Ranong Province, Thailand

The purpose of this study was to determine the factors affecting the quality development and certification of local fishery products in Thailand. The study was cross-sectional and survey method was used to collect the data. We distributed 325 questionnaires to processors of fishery products working in Ranong province. PLS-SEM was used to test the proposed hypotheses. The findings of the study indicate that supply chain had a significant relationship with product quality and certification. The findings also indicate that government regulations moderate the relationship between supply chain and product quality and certification. The current study will discuss the Thai government's policies and efforts to ensure the quality and safety of aquaculture products from “Pond to Plate” through an efficient management strategy