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The antifungal, antibacterial, and antioxidant activity of four commercial essential oils (EOs) (thyme, clove, rosemary, and tea tree) from Romanian production were studied in order to assess them as bioactive compounds for active food packaging applications. The chemical composition of the oils was determined with the Folin–Ciocâlteu method and gas chromatography coupled with mass spectrometry and flame ionization detectors, and it was found that they respect the AFNOR/ISO standard limits. The EOs were tested against three food spoilage fungi—Fusarium graminearum, Penicillium corylophilum, and Aspergillus brasiliensis—and three potential pathogenic food bacteria—Staphylococcus aureus, Escherichia coli, and Listeria monocytogenes—using the disc diffusion method. It was found that the EOs of thyme, clove, and tea tree can be used as antimicrobial agents against the tested fungi and bacteria, thyme having the highest inhibitory effect. Concerning antioxidant activity determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis 3-ethylbenzthiazoline-6-sulfonic acid (ABTS) methods, it has been established that the clove oil exhibits the highest activity because of its high phenolic content. Promising results were obtained by their incorporation into chitosan emulsions and films, which show potential for food packaging. Therefore, these essential oils could be suitable alternatives to chemical additives, satisfying the consumer demand for naturally preserved food products ensuring its safety.

In the latest years, researchers have been working to reduce the dependence on petroleum based fuels and products due to the increase in environmental consciousness. This leads to investigate the environmentally friendly sustainable materials in order to replace the existing ones. One of these polymeric materials is poly(3-hydroxybutyrate) (PHB) which is a semi-crystalline, linear polymer belonging to the class of polyhydroxyalkanoates. It is fully biodegradable and biocompatible, and produced from renewable resources. Although having promising properties, PHB is unstable during processing at elevated temperatures causing thermal degradation that reduces its mechanical performance. The purpose of the present study was to develop and characterize new composite materials based on PHB and different percentage of cellulose fibers (from 2% to 10%), in order to improve PHB's physical mechanical behavior. In this respect, a series of physical-mechanical analyses (melt processing, optical properties, differential scanning calorimetry, water vapor permeability, etc.) were performed. The results obtained during this study show the most appropriate composition of the tested mixtures and demonstrate that the polymeric material based on PHB and cellulose fibers have good physical -mechanical characteristics, being suitable for packaging industry.

The blood glucose and plasma insulin responses to some simple carbohydrates (glucose, fructose, lactose) and some complex ones (apples, potatoes, bread, rice, carrots and honey) were studied in 32 Type 2 (non-insulin-dependent) diabetic patients. Blood glucose and plasma insulin were measured at zero time and then at 15, 30, 60, 90 and 120 min after ingestion of 25 g glucose, fructose or lactose, or 30 g honey, 50 g white bread, 125 g white rice or potatoes, 150 g apples or 260 g carrots. Maximum blood glucose and plasma insulin responses were recorded 60 min after ingestion of each test meal. At this time the increases in blood glucose and in plasma insulin were significantly higher after the more refined carbohydrates (glucose, fructose and lactose) than after the more complex ones (apples, potatoes, rice, carrots and honey, -p less than 0.01). Counting the blood glucose increase after glucose as 100%, the corresponding increases in glycaemia for other carbohydrates were: fructose, 81.3%; lactose, 68.6%; apples, 46.9%; potatoes, 41.4%; bread, 36.3%; rice, 33.8%; honey, 32.4% and carrots, 16.1%.

The food industry nowadays is facing new challenges in terms of sustainability and health implications of packaging and processing techniques. Due to their desire for new and natural products coupled with changes in lifestyle, consumers are looking for food products that have been less processed but possess longer shelf life and maintain nutritional and sensorial proprieties during storage. These requirements represent real challenges when dealing with highly perishable food products, such as fruits and vegetables. Thus, in recent years, edible coatings have been intensively developed and studied because of their capacity to improve the quality, shelf life, safety, and functionality of the treated products. Edible coatings can be applied through different techniques, like dipping, spraying, or coating, in order to control moisture transfer, gas exchange, or oxidative processes. Furthermore, some functional ingredients can be incorporated into an edible matrix and applied on the surface of foods, thus enhancing safety or even nutritional and sensory attributes. In the case of coated fruits and vegetables, their quality parameters, such as color, firmness, microbial load, decay ratio, weight loss, sensorial attributes, and nutritional parameters, which are very specific to the type of products and their storage conditions, should be carefully monitored. This review attempts to summarize recent studies of different edible coatings (polysaccharides, proteins, lipids, and composites) as carriers of functional ingredients (antimicrobials, texture enhancers, and nutraceuticals) applied on different minimally processed fruits and vegetables, highlighting the coating ingredients, the application methods and the effects on food shelf life and quality.

Summary.The disappearance rate of insulin antibodies was studied after cessation of insulin treatment which had been given for 3 months to 6 years in 42 Type 2 (non-insulin-dependent) diabetic patients. Insulin antibodies were measured before and 15 days after interruption of insulin treatment, and every 30 days until the disappearance of insulin antibodies. The mean + SD value of insulin binding in the entire group before the interruption of insulin treatment was 32 + 14%. There was no relationship between the antibody level at that time and the duration of insulin treatment. However, the insulin antibody level was significantly higher in 17 diabetic patients on an insulin dose of > 20 U/day (p < 0.02) than in 25 on an insulin dose of < 20 U/day (39 _+ 13% versus 28 _+ 12%). A positive correlation was found between intial insulin binding and the time required for it to fall below 10% (r = 0.74). Antibodies were absent 60 days after discontinuing insulin treatment in eight of ten subjects presenting with initial binding of < 20%. In contrast, in only two of 12 patients with an initial binding of > 40% were insulin antibodies detectable 150 days after discontinuation of insulin therapy. Disappearance of insulin antibodies sometimes took up to 1 year and occasionally even more than 2 years.