Organic acids incorporated edible antimicrobial films

This invention provides an edible film solution comprising incorporated organic acids; protein and glycerol useful for coating raw whole fruit, fresh cut fruit, vegetables, meat, poultry, seafood, cereals, nuts, etc. Moreover, the edible films of the present invention can inhibit pathogen growth including Listeria monocytogenes, Salmonella gaminara and E. coli 0157:H7. In a preferred embodiment, the edible film comprises 0.9% glycerol; 10% soy protein; and 2.6% malic acid. A method for coating comestible products with edible films without masking the color but increasing the shelf-life is also provided

Use of flow cytometry and total viable count to determine the effects of orange juice composition on the physiology of Escherichia coli

Orange juice (OJ) contains numerous compounds some of which are known to play key roles in growth and survival of bacteria. This study aimed to investigate the effects of natural or processing‐induced variations in OJ composition on the physiology of Escherichia coli. OJ and model OJ (MOJ) samples containing various sugars, organic acids, amino acids, or ascorbic acid were inoculated with E. coli K‐12 MG1655 in different growth phases. The culturability, viability, and physiology of the cells were investigated during storage using plate counting and flow cytometry. Generally, stationary‐phase cells displayed the greatest survival in both MOJ and OJ. Increase in incubation temperature from 4 to 22.5ºC caused a significant decrease in both healthy and culturable cell populations. Supplementation of MOJ with ascorbic acid and amino acids increased both the viability and culturability of the cells. Similar trends were observed in amino acid‐supplemented OJ, albeit at a slower rate. In contrast, variations in sugar or organic acid composition had negligible effects on the physiological status of the cells. In summary, natural variation in ascorbic acid or amino acid concentrations could potentially have an adverse effect on the microbiological safety of orange juice

Investigation into Micropollutant Removal from Wastewaters by a Membrane Bioreactor

Direct potable reuse of wastewater is attractive as the demand for potable water increases. However, the presence of organic micropollutants in industrial and domestic wastewater is a major health and environmental concern. Conventional wastewater treatment processes are not designed to remove these compounds. Further many of these emerging pollutants are not regulated. Membrane bioreactor based biological wastewater treatment has recently become a preferred method for treating municipal and other industrial wastewaters. Here the removal of five selected micropollutants representing different classes of emerging micropollutants has been investigated using a membrane bioreactor. Acetaminophen, amoxicillin, atrazine, estrone, and triclosan were spiked into wastewaters obtained from a local wastewater treatment facility prior to introduction to the membrane bioreactor containing both anoxic and aerobic tanks. Removal of these compounds by adsorption and biological degradation was determined for both the anoxic and aerobic processes. The removal as a function of operating time was investigated. The results obtained here suggest that removal may be related to the chemical structure of the micropollutants