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Pulsed vacuum (PV) was used to reduce the phosphate soaking time for raw and cooked shrimp, without reducing its quality. The shrimp was soaked in a phosphate solution under cycles of vacuu...

In this study, we attempted to maximize arabinoxylan conversion into xylooligosaccharide (XOS) from rice husk and rice straw using two saccharification processes and evaluate the promotion of lactic acid-producing bacterial growth, including an investigation of the role of prebiotics in protecting probiotic bacteria in rice drink products in a high-pressure process (HPP). Hydrothermal treatment followed by enzymatic hydrolysis was designed for XOS recovery from rice husk arabinoxylan (RH-AX) and rice straw arabinoxylan (RS-AX). The hydrothermal treatment performed at 170 °C for 20 min and 180 °C for 10 min was the optimal condition to produce XOS liquor from rice husk and rice straw, respectively. Pentopan mono BG successfully recovered XOS from rice husk and rice straw residues at 50 °C, pH 5.5, an enzyme concentration of 50 U and 100 U/g substrate for 24 h. This design converted 92.17 and 88.34% (w/w) of initial RH-AX and RS-AX into saccharides, which comprised 64.01 and 59.52% of the XOS content, respectively. Rice husk xylooligosaccharide (RH-XOS) and rice straw xylooligosaccharide (RS-XOS) had degrees of polymerization ranging from 2 to 6 with some arabino-xylooligosaccharides. RH-XOS and RS-XOS were used to examine the promotion of the growth of lactic acid-producing bacteria strains in the presence of other prebiotics. RH-XOS and RS-XOS strongly promoted the growth of Lactobacillus sakei and Lactobacillus brevis, while other species showed weak to moderate growth. This study represents the first report of the powerful effect of Lactococcus lactis KA-FF1-4 on altering the utilization of XOS but not xylose. Furthermore, for the first time, we reported the capability of XOS to protect probiotics in rice drinks under high-pressure conditions. RH-XOS and RS-XOS resulted in the highest viability of approximately 11 log cfu/mL and exhibited no significant difference compared with the non-HPP treatment. Hence, rice husk and rice straw can be utilized as alternative prebiotic sources that provide biological activity and food applications in the HPP industry.

The effect of active modified atmosphere packaging with different initial gas compositions on fresh shiitake mushrooms was investigated. Shiitake mushrooms were packaged under each of the following conditions: (1) high oxygen packaging (HOP), 100% oxygen initially; (2) medium oxygen packaging (MOP), 50% O 2 and balanced with N 2 initially; (3) low oxygen packaging (LOP), 3% O 2 /5% CO 2 , balanced with N 2 initially. Passive modified atmosphere packaging with air inside initially (AIR) was used as the control treatment. All the packaged samples were stored at 10 °C with 90% RH for 7 days. During storage, gas compositions, electrolyte leakage, crude water-soluble polysaccharides, total phenolic content and free amino acid content were determined. The results showed that ethanol release was high in LOP and AIR but retarded in MOP and HOP. No packaging could prevent the decrease in polysaccharide content decreasing. Both the active and passive modified atmosphere packaging maintained the color and integrity of the mushrooms. The active modified atmosphere packaging had a significant effect on the increase of total phenolic content and total amount of free amino acids. LOP had a harmful impact on mushrooms with high levels of electrolyte leakage. In conclusion, HOP and MOP had a better effect on maintaining the nutritional compounds of shiitake mushrooms.

A variety of polyethylene terephthalate (PET) bottles commercially available as soft drink containers from 80 different brands was collected in Japan and subsequently examined to determine the amount of Sb in both the PET plastic and drink. The concentration of Sb in the plastic material ranged from 0.1 to 216.5 mg/kg, while this value ranged from 0.3 to 1.6 μg/L in bottled solutions. The diffusion coefficients of Sb in PET samples were determined at 25, 40, 55, and 70 °C. The migrated-Sb in all simulated food solutions (e.g., ultra pure water, 4% acetic acid, and 50% ethanol) increased with storage time and temperature. The temperature-dependent diffusion coefficients were derived from the Arrhenius equation. The predicted model for Sb migration suggested that storage conditions of all PET drink products should be below 70 °C for a maximum of 72 d to avoid Sb levels above the recommended value of 5 μg/L, which is based on the European standards.

The possibility use of near-infrared (NIR) spectroscopy in the region of 9000–4000 cm−1 to determine total bacterial count (TBC) in raw milk and the influence of bacterial cultivation on TBC prediction accuracy were studied. Raw milk samples were diluted 10-fold with tryptic soy broth and then cultivated at 32 °C for 2 hr. NIR measurements were performed after cultivation times of 30, 60, 90, and 120 min. Partial least squares regression was used to develop calibration models for TBC. The best calibration result was obtained from the 90 min-cultivation samples, with the correlation coefficient (R) of .90 and root mean square error of prediction of .32 log10 CFU/ml. The analysis of the calibration structure indicated that important information for TBC prediction was from chemical compositional changes and bacterial metabolites. The NIR method combined with bacterial cultivation was satisfactory for the rapid analysis of TBC in raw milk. Practical applications The number of bacteria in raw milk is an important indicator for hygienic quality and milk grading system which consequently reflects a milk price. The proposed method allows satisfied performance for TBC determination in raw milk in 90 min as compared to the 48 hr required using the plate count method. The NIR method developed in this study seems to be an effective tool for a rapid evaluation of bacterial contamination in raw milk. An integration between determination of milk hygienic quality and chemical compositional quality using NIR spectroscopy will facilitate a rapid and multicomponents analysis and become a powerful tool for a practical use in the competitive dairy industry.

An oxygen electrode was used to measure oxygen consumption to determine bacterial contamination in milk. Dissolved oxygen (DO) measured at 10-35 degrees C for 2 hours provided a reasonable prediction efficiency (r > or = 0.90) of the amount of bacteria between 1.9 and 7.3 log (CFU/mL). A temperature-dependent predictive model was developed that has the same prediction accuracy like the normal predictive model. The analysis performed with and without stirring provided the same prediction efficiency, with correlation coefficient of 0.90. The measurement of DO is a simple and rapid method for the determination of bacteria in milk.