Effect of packaging on volatile profiles of mulberry tea

This research aimed to investigate the effect of packaging materials and storage time on volatile profiles of mulberry tea. The mulberry tea samples were packaged in linear lowdensity polyethylene laminated aluminum (AL) bag and polypropylene (PP) bag and stored at 30\ub11\ub0C for 18 months. The volatile profiles were monitored using a headspace solid phase microextraction/gas chromatography-mass spectrometry. The results showed that storage time had no significant impact on the key volatile compounds of the AL packaged samples. However, some volatiles associated with lipid oxidation like hexanal and 4-oxo-2-nonenal were observed to significantly (p<0.05) increase in the PP packaged samples with storage time

CONTAMINATION PREDICTIONS OF CAPE HAKE FILLETS DURING DISPLAY AND STORAGE BY ARTIFICIAL NEURAL NETWORK MODELING OF HEXADECANOIC ACID

Published ArticleThis study aimed to design an artificial neural network (ANN) that could distinguish between Cape hake fillets displayed and stored on ice that have been exposed to excessive contamination and those that were not. The selected variable was a biochemical indicator, hexadecanoic acid, a fatty acid. Cape hake fillets with and without excessive contamination was kept on ice and analyzed every 48 h over a period of 10 days. A novel ANN was designed and applied, which provided an acceptable prediction on the contaminated fillets based only on the hexadecanoic acid changes during day 8 (T4) and day 10 (T5). The ANN consisted of a multilayered network with supervised training arranged into an ordered hierarchy of layers, in which connections were allowed only between nodes in immediately adjacent layers. The network consists of two inputs, T4 and T5 connected to two neurones that are connected to one output neuron that indicates a prediction on contamination of the fillets. These two neurons are connected to one output neuron that indicates a prediction on contamination of the fillets

Amine-responsive bilayer films with improved illumination stability and electrochemical writing property for visual monitoring of meat spoilage

Amine-responsive bilayer films were developed by using agar (AG), anthocyanins (AN), gellan gum (GG) and TiO2 nanoparticles for visual monitoring of meat spoilage. The AG-AN layer worked as the sensing layer to volatile amines, while GG-TiO2 layer served as the light barrier layer and simultaneously the conducting layer to improve the illumination stability and electrochemical writing ability of the AG-AN layer, respectively. The Scanning electron microscopy (SEM) images and X-ray diffraction (XRD) spectra indicated the successful fabrication of bilayer films. Illumination experiments showed that the incorporation of TiO2 in the GG-TiO2 layer significantly improved the illumination stability of AN in the AG-AN layer. Meanwhile, electrochemical writing process could be easily conducted on the AG-AN layer in the presence of GG-TiO2 layer, indicating the feasibility of ink-free printing on bilayer biopolymer films. The AG-AN/GG-2%TiO2 film presented a limit of detection of 0.018 mM to trimethylamine (TMA), a typical basic gas generated during meat spoilage. Based on its good illumination stability and sensing ability to basic gases, the AG-AN/GG-2%TiO2 film exhibited rose red-to-green color changes along with the spoilage of pork and silver carp, indicating its great potential for monitoring meat spoilage in intelligent food packaging

Active packaging of fish gelatin films with Morinda citrifolia oil

Active packaging is of interest in helping to prevent autoxidation process in foods. Morinda citrifolia contains a wide range of antioxidants such as ascorbic acid, terpenoids, and polyphenols. The purpose of this study was to determine the potential of Morinda citrifolia as a natural antioxidant in an active packaging film. Fish gelatin films incorporated with 1–3% of Morinda citrifolia oil (MO) were used to prepare antioxidant films. It was found that the incorporation of MO would not affect the thickness and solubility of gelatin films, independent of concentration. However, the solubility ranging from 13.4% to 13.8% might be considered low for these films. As for the mechanical properties, Young's modulus and elongation at break were not affected significantly by incorporation of 1–3% MO (p>0.05). As for the tensile strength, fish gelatin film incorporated with 1–3% MO showed a higher value than control (p≤0.05). The opacity between the samples and control varied statistically with the highest value with films containing 3% oil (p≤0.05). However, increasing the MO concentrations would decrease the water vapor permeability (p>0.05). DPPH (2,2-diphenyl-1-picrylhydrazyl) was used to determine the antioxidant activity and the result increased significantly (p≤0.05) from 9% to 16% with the increase of oil concentration, suggesting MO incorporation in films as potential means of active packaging

Computational shelf-life dating : complex systems approaches to food quality and safety

Shelf-life is defined as the time that a product is acceptable and meets the consumers expectations regarding food quality. It is the result of the conjunction of all services in production, distribution, and consumption. Shelf-life dating is one of the most difficult tasks in food engineering. Market pressure has lead to the implementation of shelf-life by sensory analyses, which may not reflect the full quality spectra. Moreover, traditional methods for shelf-life dating and small-scale distribution chain tests cannot reproduce in a laboratory the real conditions of storage, distribution, and consumption on food quality. Today, food engineers are facing the challenges to monitor, diagnose, and control the quality and safety of food products. The advent of nanotechnology, multivariate sensors, information systems, and complex systems will revolutionize the way we manage, distribute, and consume foods. The informed consumer demands foods, under the legal standards, at low cost, high standards of nutritional, sensory, and health benefits. To accommodate the new paradigms, we herein present a critical review of shelf-life dating approaches with special emphasis in computational systems and future trends on complex systems methodologies applied to the prediction of food quality and safety.Fundo Europeu de Desenvolvimento Regional (FEDER) - Programa POS-ConhecimentoFundação para a Ciência e a Tecnologia (FCT) - SFRH/BPD/26133/2005, SFRH/ BPD/20735/200

Active packaging of fish gelatin films with Morinda citrifolia oil

Active packaging is of interest in helping to prevent autoxidation process in foods. Morinda citrifolia contains a wide range of antioxidants such as ascorbic acid, terpenoids, and polyphenols. The purpose of this study was to determine the potential of Morinda citrifolia as a natural antioxidant in an active packaging film. Fish gelatin films incorporated with 1–3% of Morinda citrifolia oil (MO) were used to prepare antioxidant films. It was found that the incorporation of MO would not affect the thickness and solubility of gelatin films, independent of concentration. However, the solubility ranging from 13.4% to 13.8% might be considered low for these films. As for the mechanical properties, Young's modulus and elongation at break were not affected significantly by incorporation of 1–3% MO (p>0.05). As for the tensile strength, fish gelatin film incorporated with 1–3% MO showed a higher value than control (p≤0.05). The opacity between the samples and control varied statistically with the highest value with films containing 3% oil (p≤0.05). However, increasing the MO concentrations would decrease the water vapor permeability (p>0.05). DPPH (2,2-diphenyl-1-picrylhydrazyl) was used to determine the antioxidant activity and the result increased significantly (p≤0.05) from 9% to 16% with the increase of oil concentration, suggesting MO incorporation in films as potential means of active packaging

Applications and Advances in Electronic-Nose Technologies

Electronic-nose devices have received considerable attention in the field of sensor technology during the past twenty years, largely due to the discovery of numerous applications derived from research in diverse fields of applied sciences. Recent applications of electronic nose technologies have come through advances in sensor design, material improvements, software innovations and progress in microcircuitry design and systems integration. The invention of many new e-nose sensor types and arrays, based on different detection principles and mechanisms, is closely correlated with the expansion of new applications. Electronic noses have provided a plethora of benefits to a variety of commercial industries, including the agricultural, biomedical, cosmetics, environmental, food, manufacturing, military, pharmaceutical, regulatory, and various scientific research fields. Advances have improved product attributes, uniformity, and consistency as a result of increases in quality control capabilities afforded by electronic-nose monitoring of all phases of industrial manufacturing processes. This paper is a review of the major electronic-nose technologies, developed since this specialized field was born and became prominent in the mid 1980s, and a summarization of some of the more important and useful applications that have been of greatest benefit to man

Advances in Electronic-Nose Technologies Developed for Biomedical Applications

The research and development of new electronic-nose applications in the biomedical field has accelerated at a phenomenal rate over the past 25 years. Many innovative e-nose technologies have provided solutions and applications to a wide variety of complex biomedical and healthcare problems. The purposes of this review are to present a comprehensive analysis of past and recent biomedical research findings and developments of electronic-nose sensor technologies, and to identify current and future potential e-nose applications that will continue to advance the effectiveness and efficiency of biomedical treatments and healthcare services for many years. An abundance of electronic-nose applications has been developed for a variety of healthcare sectors including diagnostics, immunology, pathology, patient recovery, pharmacology, physical therapy, physiology, preventative medicine, remote healthcare, and wound and graft healing. Specific biomedical e-nose applications range from uses in biochemical testing, blood-compatibility evaluations, disease diagnoses, and drug delivery to monitoring of metabolic levels, organ dysfunctions, and patient conditions through telemedicine. This paper summarizes the major electronic-nose technologies developed for healthcare and biomedical applications since the late 1980s when electronic aroma detection technologies were first recognized to be potentially useful in providing effective solutions to problems in the healthcare industry