A Stable 4-Bit ALU Design for Printed Devices

Printed devices fabricated using roll-to-roll (R2R) printing technology have been used in low-cost Internet of Things (IoTs), smart packaging and bio-chips. As the area of applications of printed devices broadens, arithmetic units in digital design need to be implemented. In this paper, we propose a stable 4-bit arithmetic logic unit (ALU) design using a minimum number of transistors that can overcome the limitations of printed devices. We propose the use of a 2:1 transmission gate (TG) multiplexer (MUX) structure and hybrid 16T full-adder to construct the ALU. New design methods are applied to reduce the number of inverter stages added to overcome the voltage degradation. Using this approach reduces the total number of transistors used in the design from 276 to 153, compared to the conventional design, with significant improvements in delay and power performance.

Utilization of areca nut (Arecha chatechu L.) extract for tannin based colorimetric indicator in smart packaging

Areca nut contains tannin which has a great potential to apply as natural colour agent in food industries. Tannin offers specific colour and alter its colour due to environmental sensitivity. This study aims to fabricate a tannin-based colour indicator from areca nut in smart packaging in the form of a strip type and to characterize the indicator at different storage conditions and at various pH solutions. The indicators were synthesized using filter paper (No.1 and No.42) soaked in a solution with 1, 3, and 5% areca nut ethanolic extract. Then the indicators were stored at room temperature and 4-7°C for 10 days, then their Red Green Blue (RGB) coefficient values were measured. Characterization of the indicators at pH 3-10 were also determined by RGB coefficient. The results showed that the indicator stored at 4-7°C had more stable RGB coefficient than the indicator stored at room temperature indicated the indicator was influenced by the temperature factor. The indicator offered a potential to be used as a sensor on packaging of temperature sensitive foods. The indicator using Whatman paper No.42 with 1% of extract steadily decreased in RGB coefficient and changed its colour to darker in basic pH solution while the indicator with other treatments had unstable alteration RGB coefficient and colour.

The Preparation and Characterization of Quantum Dots in Polysaccharide Carriers (Starch/Chitosan) as Elements of Smart Packaging and Their Impact on the Growth of Microorganisms in Food

Nanocomposite materials are increasingly commonly used to ensure food safety and quality. Thanks to their unique properties, stemming from the presence of nanoparticles, they are used to develop advanced sensors and biosensors, e.g., for various harmful substances, heavy metals, microorganism growth, and environmental changes in food products. The aim of this study is to produce novel films based on natural resources—potato starch and chitosan—incorporating generated quantum dots of zinc sulfide and cadmium sulfide. The biocomposites were subjected to the following assays: FTIR spectroscopy, UV-VIS spectroscopy, photoluminescence spectroscopy, and SEM/TEM spectroscopy. Their mechanical properties were also analyzed, a colorimetric analysis was performed, and the water content, solubility, and water absorption capacity were determined. A storage test was also performed, using poultry meat covered with the produced films, to assess the microbiological quality. The results confirmed the presence of the quantum dots in the starch–chitosan matrix. The unique optical properties of the films were also demonstrated. It was shown that the composites with nanoparticles limited the growth of selected microorganisms in poultry meat. The food storage time was found to have an impact on the fluorescent properties of the composites. The results point to the possibility of using the produced films as active and smart packaging.

Plasticor: Smarting Food Packages

Food waste that occurs at different stages from food production to transportation and in homes is an economic, social and environmental problem. These food scraps are largely responsible for the generation of greenhouse gases (GHG). In addition, many of these foods are sold in non-biodegradable plastic packaging that results in the accumulation of plastic in the environment, directly and/or indirectly affecting the lives of animals and humans. In order to bring about a possibility of reducing food waste and the accumulation of long-lasting plastics in nature, Plasticor was developed, a biodegradable and sustainable polymer used in the packaging of foods that use biosensors to test the viability for human consumption of food. A smart packaging that involves food and has its color changed when the product is no longer fit for consumption, indicating the presence of harmful microorganisms. Thus, avoiding the early disposal of food in good condition and consequently its impact on the environment, in addition to postponing the consumption of new products, Plasticor contributes to a more sustainable world.

A short review: Nanocellulose for smart biodegradable packaging in the food industry

The role of food packaging has increased beyond by changing consumer preferences and expectations. In addition to these essential functions, the packaging extends shelf life, improves quality, and develops from environmentally friendly material. Nanocellulose is one of the renewable and natural source products that has been widely studied. Nanocellulose can develop into food packaging material due to its properties of oxygen and water vapor barriers when used as layers, fillers in composites and thin films stand cents. However, the use of nanocellulose is still limited due to its lack of physical properties. On the other hand, research in nanocellulose for smart packaging applications enhanced with several sensors or indicators accelerated in the last decade. This review mainly summarizes the fundamental properties of nanocellulose as a food packaging material, preparation nanocellulose material, their application on smart packaging, and their future perspective. The selection of nanocellulose material preparation methods and the selection of active ingredients that play a role in active and intelligent functions in packaging considerably determine the success of nanocellulose applications in food packaging main criticism appears of the difference between the results obtained in the model test and actual food storage conditions.