Development and analysis of a multi-module peristaltic simulator for gastrointestinal research.

Many existing in vitro digestion systems do not accurately represent the peristaltic contractions of the gastrointestinal system; most of the systems that have physiologically-relevant peristaltic contractions have low throughput and can only test one sample at a time. A device has been developed that provides simulated peristaltic contractions for up to 12 digestion modules simultaneously using rollers of varying width to modulate the dynamics of the peristaltic motion. The force applied to a simulated food bolus varied from 2.61 ± 0.03 N to 4.51 ± 0.16 N (p < 0.05) depending on roller width. Video analysis showed that the degree of occlusion of the digestion module varied from 72.1 ± 0.4% to 84.6 ± 1.2% (p < 0.05). A multiphysics, computational fluid dynamics model was created to understand the fluid flow. The fluid flow was also examined experimentally using video analysis of tracer particles. The model-predicted maximum fluid velocity in the peristaltic simulator incorporating the thin rollers was 0.016 m/s, and the corresponding value measured using tracer particles was 0.015 m/s. The occlusion, pressure, and fluid velocity in the new peristaltic simulator fell within physiologically representative ranges. Although no in vitro device perfectly recreates the conditions of the gastrointestinal system, this novel device is a flexible platform for future gastrointestinal research and could allow for high-throughput screening of food materials for health-promoting properties under conditions representative of human gastrointestinal motility.

Hygienic assessment of fish handling practices along production and supply chain and its public health implications in Central Oromia, Ethiopia.

Fishborne diseases are among the major causes of morbidity and mortality worldwide. Contamination of the aquatic ecosystem and unhygienic handling practices along the fish supply chain can lead to a contaminated fish. Consumption of raw or under cooked fish and fish products is a major source of fishborne infections in humans. Despite reports of fish contamination with foodborne pathogens in Ethiopia, information regarding the hygienic status of fish handling practices is limited. We assessed fish hygienic handling practices at production sites and along the fish supply chain in three towns in east Shewa zone of Oromia. Data were collected using a semi-structured questionnaire interviews and personal observations. The study consisted of purposively selected respondents comprising of 50 fishermen, 10 retailers, 20 food establishments serving fish, and 120 consumers. Descriptive statistics and Chi-square test were used to present the proportion of various actors along the fish production and supply chain and to compare the proportions of observations among the different categories respectively. We observed that the lakes were accessible to animals and exposed to chemical and microbial contaminations through rainwater run-off. Fish were processed under unhygienic practices like washing of filleted fish with lake water, indiscriminate processing at unhygienic landing sites, use of a single knife for processing all fish with infrequent washing and with no disinfection in between. Majority (70%; n = 10) of the retailers and all the food establishments transported fish in vehicles with no cold chain facilities. Good hygienic practices we observed were the use of refrigerators for storage in all retailers and 70% (n = 20) of the food establishments; 30% of retailers used vehicles with a cold chain facility for the transportation of fish. Over three-fourths (77%; n = 120) of the consumers preferred consuming raw fish; 80% of them lacked the knowledge of fishborne diseases. The study revealed a wide range of unhygienic handling practices along fish production and supply chain; lack of infrastructure for post-harvest fish handling and processing, lack of appropriate transportation facilities and presence of knowledge gaps regarding fish borne diseases.

The impact of emerging domestic and commercial electro-heating technologies on energy consumption and quality parameters of cooked beef.

The purpose of this study was to investigate the effects of e-Cooker® and moderate electric field (MEF) cooking on physical and chemical changes occurring during the cooking of meat. Beef muscle samples (38.86 ± 0.08 g) were cooked in saline solution (0.5% w/w NaCl) to a target temperature of 72 °C, followed by a 2 min holding time. The experimental results revealed that e-Cooker® and MEF significantly reduced the come-up time required to achieve a target temperature of 72 °C to 1.16 ± 0.02 min and 0.86 ± 0.02 min, respectively compared to 14.12 ± 0.55 min in conventional cooking. The colour and instrumental texture of cooked meat by e-Cooker® and MEF systems were not significantly different (P > 0.05) from conventionally cooked ones. Overall, the results obtained demonstrated that e-Cooker® and MEF can be used to cook meat in a shorter time and reasonably low energy input while producing a product which is comparable in quality to conventionally cooked meat.