During the Napoleonic era in France, French Nicolas Appert developed sterilize and save foods, and he published ”Le livre de tous les menages, ou L'art de conserver pendant plusieurs annees, toutes les substances animalse et vegetales” (1810). At the time, Spontaneous generation theory was the most widely accepted idea, theafore his tecnology did not become populer in the world. Today, with 200 years having passed since then, various packaged containers such as canned food, plastic bottle, retort pouch are used in everyday life. In special section, maicroscopic organism heat sterilization, atmospheric discharge plasmas sanitizing method , small metallic contaminant detector, rapid thawing device, barrier enhancement technology for PET bottles, inkjet printer are explained.
This review provides introduction of food sterilization using electro-magnetic heating, joule (the ohmic) heating, and retort. First, the categorization and heat resistance of micro-organism and the basic theory of heat sterilization are described. Secondly, current status of retort sterilization and the latest development status of food sterilization using electro-magnetic heating and Joule heating are introduced. The purpose of this report is to generate interest in food sterilization to members of the Japan Society of Applied Electromagnetic and Mechanics(“JSAEM”) with ultimate aim for JSAEM members to enter into research and development of food sterilization.
Agricultural products were sterilized by irradiation with active oxygen species produced by the combination of atmospheric plasma and UV light in ambient air. It was found that the surfaces of rice and lemons are sterilized after 20 min of irradiation. After the irradiation, the mold spores on the surface, although still viable, become unculturable. Treatment speed using the active oxygen species is higher than that using plasma or UV light alone. Infrared light spectra of the fruits surface indicate that there is no significant damage to the exocarp caused by the active oxygen species.
We developed a practical magnetic metallic contaminant detector using three high-Tc RF superconducting quantum interference devices (SQUIDs) for food inspection. The system was covered with waterproof stainless steel plates, and the outer dimensions of the system were 2450 mm (W) × 714 mm (D) × 1555 mm (H). An acceptable inspected object size was 150 mm (W) × 100 mm (H), which is sufficiently large for practical food inspection. A digital filtering technique has been newly introduced to reduce noise. As a result, the signal-to-noise ratio (SNR) was dramatically improved, and we were able to robustly detect a steel ball as small as 0.3 mm in diameter.
Thawing method by using dielectric heating can rapidly heat food with less temperature difference between the surface layer and inside of the food, because the food itself becomes a heat-generating element. Compared with microwaves (300MHz～30GHz), radio frequency waves (3MHz～300MHz) are so suitable for thawing that hot spots and thermal runaway hardly occur. The half-thawing state at slightly lower temperature range -5 to -1°C than the freezing point is called “Tempering”, which is distinguished a complete-thawing state. “Tempering” has been variously utilized for frozen food processing. Herein we introduce thawing cases and an overview of batch type and continuance type radio frequency thawing equipments.
The enhancement of the gas barrier property of plastic bottles is demanded in the food and beverage industry for improved quality retention. Amorphous carbon (DLC) coating is used for high barrier PET bottles, where a plasma chemical vapor deposition technique with radio frequency is employed. This article introduces the advancements of this technology and possible further applications.
Industrial, continuous inkjet printers (CIJP) have been widely used for growing needs of traceability of food. To apply the CIJPs on new print targets, the CIJP and ink for new specification must be developed. To develop new CIJPs, an ink particle flight simulation has been utilized. Ink composition is designed with the material of print target appropriately. Needs for the total marking system are growing due to recent requirement for traceability of foods.
There are many challenges facing people with disability in their daily life. To support them, many instruments are developed. In this research, a robot arm system was designed, developed and controlled by use of an EOG (ElectroOculography) signal generated by the eye movement. To get the gaze position through EOG, an estimation method of gaze positions was proposed. The method is to use vector and maximum value of EOG. The error range between real gaze and estimated gaze motions and positions was from -4° to +10°. To improve the controllability of the system, a switch was introduced. It works when operator blinks. The function of the switch is to change the method of gaze motion and position estimation. One of them is estimation in two dimensions, the other is estimation in four directions (up, down, right and left). To prove the efficiency of the switch function, two experiments were done. Operators got the tip of the robot arm coincided with targets by using this system. In the experiments, one was the system with the switch. The other was the system without switch. The finished time of the experiment with switch was half, compared with the experiment without the switch. The results proved the efficiency of the switch.