Ozlem Kizilirmak Esmer

Multilayer packaging materials are extensively used in food packaging, particularly for powdered products. In alignment with sustainable development goals, packaging design should aim to minimize material usage while maintaining the protective properties necessary to preserve food quality and safety, thereby reducing environmental impact. A key strategy is to simplify multilayer structures to enhance recyclability. This study aims to evaluate the potential of sustainable alternative packaging materials with reduced metal and plastic content and improved recyclability for pudding powder packaging, as substitutes for conventional films. Four packaging structures were tested: a conventional three-layer laminate (polyethylene terephthalate (PET)/aluminum foil (Al-foil)/low-density polyethylene (LDPE)), two two-layer structures (AlO_x-coated PET/LDPE and Al-coated PET/LDPE), and a monolayer metallized biaxially oriented polypropylene (MetBOPP). Samples were stored under accelerated conditions (38 °C and 90% relative humidity) for 180 days, and changes in moisture content, water activity, caking degree, glass transition temperature, color, and sensory attributes were monitored. The experimental data were examined for their agreement with various sorption models by creating adsorption isotherms. The acceptable storage period was estimated using the constants calculated from these models. Statistically significant differences (p < 0.05) were observed among the packaging types, primarily associated with their water vapor permeability, affecting moisture content, water activity, caking degree, and color stability. In terms of moisture content, water activity, and caking degree, the conventional PET/Al-foil/LDPE (Polyethylene terephthalate/Aluminum foil/Low density polyethylene) structure demonstrated the best performance, followed by PET.AlO_x/LDPE (AlO_x-coated Polyethylene terephthalate/Low density polyethylene), MPET/LDPE (Metallized polyethylene terephthalate/Low density polyethylene), and MBOPP (Metallized biaxially oriented polypropylene), respectively. The sensory analysis scores followed the same ranking; however, all samples maintained scores above the threshold value of 3 throughout the storage period, indicating that they remained acceptable. Caking degree increased moderately (from 0.61% to 0.89%) and was negatively correlated with appearance scores (R² = −0.89, p < 0.01). Despite slight darkening (Browning Index increased from 18.16 to 20.37), sensory scores for appearance, odor, and taste remained above the acceptable threshold (score > 3.0). Based on the WVTR values of the packaging materials and the application of the GAB model, the estimated shelf lives were 800.32 days for PET/Al-foil/LDPE, 577.92 days for PET.AlO_x/LDPE, 407.58 days for MPET/LDPE, and 229.26 days for MBOPP. In conclusion, the longest shelf life was achieved with PET/Al-foil/LDPE, and it was observed that as the WVTR of the packaging materials increased, the shelf life of the cocoa-based pudding powder decreased; PET.AlO_x/LDPE and MPET/LDPE could be considered for medium-term storage (up to about 1–1.5 years), while MBOPP appeared suitable only for shorter durations (6–8 months).

Research background. Artichoke leaves, an important waste product of the food industry, have an important antioxidant and antimicrobial capacity. Although there are several studies in the literature to determine their antioxidant and antimicrobial activity, a comparison of green extraction technologies including microwave, ultrasound probe and ultrasound bath methods in relation to the maceration technique has not been performed. Also, several parameters such as the extraction temperature, power, extraction mode and extraction time are important parameters for obtaining targeted compounds in the highest amount. For this reason, we aimed to compare various extraction methods including microwave-assisted extraction, ultrasound-assisted extraction with probe, ultrasound-assisted extraction in a water bath and maceration in terms of extraction parameters for obtaining bioactive compounds from artichoke leaves. Experimental approach. Microwave-assisted extraction at two different power values, ultrasound-assisted extraction with probe in continuous or pulsed mode with two different extraction times each, ultrasound-assisted extraction in a water bath at two different power values with two different extraction times each and maceration with two different times were used for the extraction. The extraction temperature is an important parameter affecting the thermal degradation of bioactive compounds. We used a constant extraction temperature of 50 °C. Total phenolic and total flavonoid content, antioxidant capacity, phenolic compound profile analysis by LC-QTOF-MS and antimicrobial activity by agar diffusion and broth microdilution methods were determined. Results and conclusions. The bioactive compounds were found to be significantly affected by the parameters used in each extraction method. The microwave-assisted extraction method was more efficient than the other extraction methods at both power values. This method also required the shortest extraction time. The ultrasound-assisted probe extraction method was the second most efficient method. The type of process, continuous or pulsed, did not affect the results, but shortening the extraction time led to lower results. A longer extraction time of the ultrasound-assisted extraction in a water bath method led to better results, similar to the ultrasound-assisted probe extraction, regardless of the used power. The extracts were highly effective against many opportunistic and pathogenic microorganisms. Novelty and scientific contribution. This study provides valuable insights into the extraction parameters of different extraction methods to obtain bioactive compounds from artichoke leaves, which could have potential applications in the food and pharmaceutical industries.

This study aimed to determine the effects of carbon dioxide concentration in modified atmosphere packaging (MAP) on the quality criteria and shelf life of whole wheat flour bread. Four different concentrations of CO₂ and N₂ gases (30% CO₂ + 70% N₂, 50% CO₂ + 50% N₂, 70% CO₂:30% N₂ and 100% CO₂) were applied to the bread samples, which were packaged with PA/EVOH/LDPE (polyamide/ethylene vinyl alcohol/low‐density polyethylene). The samples were stored at room temperature (25°C ± 1°C) for 13 days. The control group was packaged using BOPP (bi‐oriented polypropylene) under atmospheric air as in traditional current use. The effects of MAP on headspace gas analysis, pH, moisture content, water activity, water‐holding capacity, blue value, hardness, total mould and yeast count and sensory evaluation were analysed on days 0, 3, 4, 5, 7, 10 and 13. The results showed that the most effective gas combination in extending the shelf life of whole wheat bread was 100% CO₂, and its shelf life was 10 days, whereas it was only 3 days for the control group. Increasing concentrations of CO₂ significantly affected mould and yeast growth. As the CO₂ concentration increased, the bread exhibited higher water‐holding capacity and blue values, which are important indicators for bread staling. An improved preservation of sensory properties was observed in proportion to increasing CO₂ concentrations. However, the CO₂ gas concentration did not affect the hardness of the bread. Overall, the study suggests that MAP technology, particularly using 100% CO₂, can effectively extend the shelf life of whole wheat flour bread without the need for preservatives, not only extending the microbiological shelf life but also increasing the sensory shelf life. The species that grew in air‐packaged samples were suppressed under modified atmosphere conditions and chalk mould fungi were the dominant and shelf life‐impacting species in the MAP samples. These findings could be beneficial in reducing bread wastage, which is a critical issue in today's society due to the limited shelf life of bread caused by rapid microbiological deterioration or staling.

This study aims to optimize the extraction conditions to obtain the highest yield, to characterize tomato peel extract (TPE) under optimized conditions, and also to determine the effect of ambient oxygen on the properties of TPE. Optimisation were performed at three temperatures (60 °C, 80 °C, 100 °C) and three periods (2, 4, 6 h) by the response surface methodology. The properties of the extract under atmospheric and oxygen-free conditions (AC, OFC) were analysed to determine whether the characteristics of both extracts changed depending on the presence of oxygen; moreover, the morphological, chemical, thermal, biochemical, and antimicrobial properties were analysed. The maximum yield was 31.3% at 100 °C/6 h. A quadratic model was used to create the best fit. Both TPE samples exhibited similar morphological structure, similar weight losses at three stages of TGA curve, similar band assignments in FTIR spectra. GC-MS analysis showed that both samples mainly consisted of cutin in abundance of 70.45% and 68.14% for AC and OFC, respectively. OFC had higher total phenolic content possibly depending on the absence of oxygen. AC and OFC extracts exhibited substantial antimicrobial activity against S. aureus, E. coli, C. albicans, and A. brasiliensis with a MIC value of 100 μg TPE/ mL.

With the increasing world population, the food need of humanity is increasing proportionally. Agricultural wastes constitute an important potential for the global economy as they contain components that are less preferred to be consumed as food due to their low bioavailability due to their indigestion in the human body or due to their sensory properties, but that may be beneficial to human health such as antioxidant substances and antimicrobial agents. The benefits of using these wastes in terms of economy and reducing environmental pollution are obvious. Tomato, which is one of the most used agricultural products in our country and the world, is processed by removing its skins in the processing of many products. Tomato skins cause serious environmental problems and economic losses unless they are valorized. In this regard, this study aims to optimize the extraction efficiency, the antioxidant capacity, and total phenolic content of the tomato peel extract according to the independent variables of temperature and time, while the alkaline extraction process applied to tomato skins is cheap and industrially applicable. Using response surface methodology, the highest extraction yield (28.77 g/100 g dry extract), total phenolic content (3819.32 mg GAE/100 g dry extract), and total antioxidant capacity (2737.82 µmoL Trolox/100 g dry extract) were obtained under extraction conditions at 100°C for 5.26 h. According to LC-MS/MS results, tomato skins treated with alkali contain various phenolic acids and some flavonoids. The phenolic component found in the highest amount in the tomato peel extract was determined as p-coumaric acid (429.99 ± 38.53 mg/100 g dry extract). Other important phenolic components are ferulic acid (12.44 ± 2.06); 4-hydroxy benzoic acid (7.13 ± 1.01) and vanillin (2.47 ± 0.22) mg/100 g dry extract.

Fresh mushrooms have a very short shelf life, of 1 – 3 days because of their high respiration rate and lack of cuticles that protect the plant from external factors. In the case of fresh-sliced mushrooms, they will be more susceptible to spoilage reactions due to the increase in respiration rate as a result of a broader surface area. Conventional packaging materials can not meet the requirements for modified atmosphere packaging of fresh-sliced mushrooms. One of the techniques to extend the fresh-cut produce shelf life is the passive modification of modified atmosphere packaging technology. For highly respiring fresh-cut produce such as fresh-sliced mushrooms, the permeability properties of the polymeric materials might not be enough to provide an equilibrium gas concentration in the passive modification of modified atmosphere technology. In this case, the microperforated packaging materials can be used for passive modification of fresh-cut produce. But the microperforation process needs a design for the application of the appropriate number and diameter of microholes to meet the requirements of passive modified atmosphere packaging. For this reason in this research, the design of the microperforation process to be used in passive modified atmosphere packaging was based on the diameter and the number of microholes, and the shelf life of fresh-sliced mushrooms was determined. The samples were stored at 15 °C/80% RH, and pH, color, weight loss, textural, sensorial, and microbial analysis were performed periodically during storage. It was determined that the empirical equation used in this research can be applied to microperforated packaging design for fresh-sliced mushrooms. The shelf life of the fresh-sliced mushrooms packaged with microperforated packaging material was 8 days, while it was less than 7 days (4, 5, or 6 days) when packaged with non-microperforated packaging material. This result shows that the use of microperforated packaging material is effective in extending the shelf life of fresh-sliced mushrooms.

Polycarbonate (PC) materials are widely used for the packaging of drinkable water. The use of PC materials as food packaging raises some concerns for the migration of Bisphenol A (BPA), which is the monomer of PC. Therefore, in this research, it was aimed to determine the quality of new and old (life time ended) PC water carboys in terms of residual BPA and BPA migration levels with respect to storage conditions. For this purpose, BPA migration was determined by storing at three different temperatures (5, 20 and 40C) for seven different storage times (1., 5., 10., 20., 30., 45. and 60 days.) Residual and migrated BPA levels were determined by High Performance Liquid Chromatography with Fluorescence Detector. As a result, PC water carboys contained low levels of residual of BPA, and lower or higher residual BPA levels were detected in old materials compared to new materials. The BPA migration level increased by temperature and time, and storage under sunlight increased the level of BPA migration. BPA migration levels under all storage conditions were below the specific migration limit for BPA. In order to reach the tolerable daily intake of BPA even under the worst storage condition of PC water carboys, daily water consumption was calculated as 16 liters for a person with a body weight of 60 kg. On the other hand, this daily water consumption might not be rational for a person. Therefore, it was concluded that PC water carboys possessed no risk in terms of BPA migration levels under the conditions studied.

Polikarbonat (PC) malzeme, gıda ile temas eden malzemelerden özellikle su damacanaları ve sofra malzemelerinin üretiminde yaygın şekilde kullanılmaktadır. Bisfenol-A (BPA) ise PC malzemelerin üretiminde kullanılan önemli bir monomerdir ve son yıllarda BPA’nın PC malzemelerden gıdaya geçebildiği ve insan sağlığı üzerinde olumsuz etkilerinin olabileceği doğrulanmıştır. PC malzeme farklı sıcaklıklarda farklı sürelerde su ile temas halinde bulunabilmekte, yıkama, sterilizasyon gibi tekrarlayan işlemlere maruz kalabilmektedir. Nem, yüksek sıcaklık gibi farklı çevresel koşullara maruz kaldığında PC malzemenin degrade olabileceği ve PC malzemenin degradasyona uğraması sonucunda malzemede bulunan BPA miktarında değişiklik olabileceği bazı çalışmalarda gösterilmiştir. Bu nedenle bu çalışmada su ile temas halinde kullanılan PC malzemelerde BPA migrasyon mekanizması incelenmiş, PC malzemenin maruz kaldığı sıcaklık, süre ve tekrarlayan işlemlerin BPA migrasyonuna etkisi araştırılmıştır.

Tavuk eti yüksek protein ve nem içeriği nedeniyle hem mikrobiyal hem de biyokimyasal bozulmalara oldukça açık olmasından dolayı raf ömrü kısa olan bir gıdadır. Ayrıca gerek gıdanın doğası gerek işleme koşulları nedeniyle patojen mikroorganizmalarla kontamine olma ihtimalinden dolayı taze tavuk etinin güvenilir bir şekilde üretimini arttırmak ve son tüketiciye ulaşana kadar israf olmasını önlemek amacıyla mikrobiyal güvenilirliğini sağlamak oldukça önemlidir. Taze tavuk etlerinde koruyucu katkı maddeleri ilavesi, ısıl işlem uygulamaları ve/veya dondurma vb. gıda muhafaza yöntemleri kullanılmadığından üründe gerçekleşebilecek biyokimyasal değişimler ve mikrobiyal bozulmaları önlemek için ambalajlama teknolojilerinden yararlanılması işlenmiş gıda ürünlerine göre daha da önem kazanmaktadır. Yenilikçi ambalajlama teknolojileri ile taze tavuk etlerinin kalitesi arttırılıp raf ömrü uzatılabilir ve böylece güvenilirliği de daha iyi sağlanabilir. Bu bağlamda aktif ambalajlama teknolojilerinden yararlanılabilir. Bu amaçla ambalaj malzemesine ya da ambalaj ortamına eklenen antimikrobiyal maddeler, antioksidan maddeler, CO2, etanoL vs. gibi aktif maddelerin etkisiyle gıdanın özellikleri ambalajlandıktan sonra da iyi bir şekilde muhafaza edilebilmektedir. Son yıllarda taze tavuk etlerinin aktif ambalajlama teknolojisi ile ilgili olarak yapılan çalışmalarda; antimikrobiyal ya da antioksidan özelliklerde esansiyel yağlar ile doğal bitki ya da gıda sanayii atıklarından elde edilen ekstraktlar kullanılarak hazırlanan sentetik ve/veya biyobozunur polimerler kullanılmaya başlanmıştır. Bu teknoloji ile ambalajlanmış taze tavuk etlerinde bozulma yapan mikroorganizmaların üreme hızlarının yavaşlatıldığı, patojen mikroorganizmaların üremesinin engellendiği ve/veya lipid oksidasyon hızının azaltıldığına yönelik sonuçlar bulunmaktadır. Bu derleme makalesinde aktif ambalajlama uygulamalarının son yıllarda gerçekleştirilen bilimsel çalışmalar temelinde taze tavuk etlerinin kalitesi, güvenilirliği ve raf ömrü açısından etkileri incelenmiştir.