Czech Journal of Food Sciences - In Press
Enhancing Labneh with Freeze-Dried Fruits or Fruit Flavours: Effects on Physicochemical, Microbiological, and Sensory PropertiesOriginal Paper
Bayram Çetin, Christina Rehagel, Ömer Akineden
The present study aimed to formulate a novel labneh variant containing freeze-dried fruit pieces or fruit flavour and to evaluate their influence on physicochemical properties, microbiological quality, and sensory acceptance during storage. For this purpose, fruit-piece labneh was prepared by incorporating 6% freeze-dried strawberry, blackberry, or kiwi pieces, while fruit-flavoured labneh was formulated by adding 0.01% colouring and 0.1% fruit flavour derived from strawberry, blackberry, or kiwi juice. The labneh variants developed in this study were subjected to an additional post-fermentation pasteurisation followed by hot filling. Samples were analysed on days 1, 7, 15, and 30 of storage for selected physicochemical, microbiological and sensory parameters. Compared to plain labneh, fruit-piece samples showed an increased dry matter content, except for those containing kiwi. Conversely, water activity and fat content decreased, and variations in titratable acidity and pH were influenced by the type of fruit added. Microbiological analyses based on classical indicator microorganisms revealed low levels of total aerobic mesophilic bacteria in the range of 1.5 × 10^1 to 8.1 × 10^1 CFU/g. Enterobacteriaceae, Escherichia coli, yeasts and moulds were not detected, indicating good product safety. Notably, structural defects such as syneresis and increased bitterness were determined in kiwi-piece samples during storage. Sensory evaluation indicated that strawberry-flavoured, blackberry-flavoured, and strawberry-piece labneh were the most preferred by panellists. Overall, fruit- or flavour-enriched labneh produced with an additional post-fermentation heat treatment represents an attractive option for product diversification in the dairy industry. Based on their satisfactory safety, good microbiological stability and high sensory acceptance, these variants offer strong potential for industrial application.
Antimicrobial effect of Thymus vulgaris and Rosmarinus officinalis L. essential oils against gram positive bacteria inoculated in cooked turkey breasts stored under differing temperatureOriginal Paper
Talal LAHRECHE, Karima AOUES, Lydia Yasmine KEBIR
In order to simulate post-cooking contamination, the study evaluated the effects of storage temperature on the antibacterial activity of essential oils (EO) of Rosmarinus officinalis L. (0.6%) and Thymus vulgaris (0.3%) added to cooked turkey breasts inoculated with Staphylococcus aureus (ATCC 25923), Bacillus cereus (ATCC 14579), and Listeria innocua (ATCC 33090). The turkey breasts were packaged aerobically and stored at 3 ± 1°C for 120 hours, 8 ± 1°C for 120 hours, and 3 ± 1 °C for 24 hours, followed by 12 hours at 25 ± 1 °C, and at 3 ± 1 °C until the end of storage (120 hours). Sensory assessments and microbial analysis were performed at 0, 24, 36, 72, and 120 hours of storage. A GC-MS was used to analyze the components of the Eos; the major components in rosemary EO were 1.8-Cineole (40.99%), α-Pinène (13.40%), and Camphre (10.92), while thyme EO was dominated with thymol (35.72%), o-Cymene (20.65%), and γ-Terpinene (8.81%). Thyme EO application led to a significant (p
CaCl2-Cold Storage Combination: An Effective Preservation Strategy for Extending the Shelf Life of Passion FruitOriginal Paper
Xiaoying Zhang, Ye Wang, Jiayu Li, Zixiong ZHANG, Caixia Chen, Yao Teng, Xiuqin Long
Passion fruit is a highly perishable climacteric fruit, prone to rapid postharvest deterioration such as pericarp shrinkage and pulp separation. To address these issues, this study investigated the efficacy of a combined treatment involving calcium chloride and low-temperature storage for preserving the quality of ‘Qinguo No. 9’ passion fruit. The results revealed that the integrated CaCl₂+4°C treatment most effectively inhibited weight loss and maintained a high edible rate by enhancing cellular integrity and moisture retention. Moreover, this approach significantly slowed the decline of essential quality indicators, including soluble solids, soluble sugars, vitamin C, total phenols, and flavonoids, thereby supporting both sensory and nutritional value. The most notable preservation effects were observed on the sixth day of storage, underscoring the treatment’s role in mid-term quality maintenance. Multivariate principal component analysis (PCA) further confirmed that fruits subjected to CaCl₂+4°C consistently received the highest overall quality scores across the entire storage duration. These findings indicate that the combined CaCl₂ and low-temperature treatment offers a practical and effective method for mitigating postharvest losses and extending the marketable life of passion fruit within commercial supply chains.
Preparation and Characterization of Antioxidative Edible Films Based on Cocoa Pods Extract Incorporating Black or Green Tea ExtractOriginal Paper
Triana Lindriati, Siti Mutimmah, Maryam Husnul Istiqomah, Melania Anggraini, Herlina Herlina, Sih Yuwanti, Asmak Afriliana, Aji Sukoco
Cocoa pods are an underutilized waste material, rich in pectin (18.12%) and polyphenols (46–69 mg GAE/g). This study aimed to explore the potential of cocoa pods extract for producing antioxidative edible films by incorporating black or green tea extracts. Five edible film samples were prepared: 1. EF (control, edible film with the solvent being 100% distilled water), 2. BTE 50 (edible film with the solvent being 50% v/v black tea extract), 3. GTE 50 (edible film with the solvent being 50% v/v green tea extract), 4. BTE 100 (edible film with the solvent being 100% v/v black tea extract), and 5. GTE 100 (edible film with the solvent being 100% v/v green tea extract). The addition of tea extracts as solvents significantly (p ≤ 0.05) improved the total polyphenol content, antioxidant activity, and tensile strength of the films while reducing solubility, the water vapor transmission rate (WVTR), and elongation. Green tea extract exhibited more pronounced effects compared to black tea extract.The GTE 100 demonstrated a total polyphenol content of 18.09 ± 1.49 mg GAE/g and a DPPH radical inhibition rate of 52.28 ± 2.6% and also showed the most significant effect in inhibiting the peroxide value of peanut oil. FTIR analysis revealed that using tea extract as a solvent improved the interaction between macromolecules through hydrogen bonding. There were no covalent or ionic bonds between the polyphenols and the macromolecule-based components of the edible film. The increase in hydrogen bonds had a positive effect on increasing tensile strength and decreasing solubility and WVTR.
Understanding the role of Taraxacum mongolicum polysaccharide for corn starch gel amelioration: Physicochemical and structural propertiesOriginal Paper
Mei Lu, Yining Dou, Jialing Xu, Yuanyuan Zhang
This paper aims to investigate the effects of Taraxacum mongolicum polysaccharides (TMPs) on the pasting, rheological, gel properties, and structural properties of corn starch (CS) by using different methods. The results show that TMPs could markedly enhance the peak, breakdown, and setback viscosities. TMPs–CS gels showed shear-thinning behavior, and TMPs could effectively improve the viscoelasticity of TMPs–CS gels, and TMPs could enhance the gel strength and hardness of TMPs–CS gels. Moreover, TMPs could enlarge the size and increase water holding capacity of TMPs–CS gels, whereas TMPs could decrease the relative crystallinity of TMPs–CS gels. Furthermore, TMPs could be bound to CS through non covalent interactions by infrared spectroscopy analysis, and TMPs could increase the thermal stability, reduce ΔH values of TMPs–CS gels, and reduce its thermal decomposition temperature. The microstructure of TMPs–CS gels exhibited the honeycomb-like porous structure, and TMPs could enhance the pore size and accelerate the destruction of TMPs–CS gels particles. The findings contribute to expanding the application of polysaccharides in starch-based foods.