Food Packaging
Lucia Daniel Tluway; Yusto Yustas; Rashid Suleiman
Abstract
This study evaluated pineapple peels as a source of cellulose and nanocellulose for bio-based packaging materials. Cellulose was extracted from pineapple peel powder through alkaline and bleaching treatments, then converted to nanocellulose by sulfuric acid hydrolysis. The physicochemical, lignocellulosic, ...
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This study evaluated pineapple peels as a source of cellulose and nanocellulose for bio-based packaging materials. Cellulose was extracted from pineapple peel powder through alkaline and bleaching treatments, then converted to nanocellulose by sulfuric acid hydrolysis. The physicochemical, lignocellulosic, and structural properties were assessed for packaging applications. Progressive changes were observed during the conversion from pineapple peel powder (PPP) to cellulose (PPC) and nanocellulose (PPNC). Moisture content declined from 8.83 ± 0.48% in raw PPP to 3.75 ± 0.10% in PPNC (P < 0.001), while ash content decreased from 5.90 ± 0.30% to 2.64 ± 0.58% (P < 0.01), showing effective removal of inorganic residues. Bulk density increased from 0.28 ± 0.01 g/mL in PPP to 0.55 ± 0.03 g/mL in PPC, then dropped to 0.39 ± 0.03 g/mL in PPNC (F = 52.68, P 0.01). Water absorption capacity fell from 390 ± 1.41% to 171 ± 5.66% and slightly rose to 201 ± 8.49% (F = 797.94, P < 0.001), while water solubility index increased from 16.02 ± 0.76% to 90.75 ± 6.70% (F = 205.77, P < 0.001). Hemicellulose and lignin decreased, cellulose increased, and FTIR confirmed removal of non-cellulosic components. These results identify the peel of Smooth Cayenne pineapple grown in Tanzania as a viable, low-cost feedstock for nanocellulose production, and they quantify the filler properties that govern the formulation of bio-based packaging films.
Food Packaging
Zolaykha Shiravani; Mohieddin Kazemi
Abstract
This study aimed to investigate the effects of active bacterial nanocellulose (BNC) films immersed in sodium nitrite (SN; 30, 60, and 120 ppm), sumac extract (SE; 10% w/v), and black carrot extract (BCE; 5% w/v) solutions on the microbial and chemical properties of ground beef. The addition of SN, SE ...
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This study aimed to investigate the effects of active bacterial nanocellulose (BNC) films immersed in sodium nitrite (SN; 30, 60, and 120 ppm), sumac extract (SE; 10% w/v), and black carrot extract (BCE; 5% w/v) solutions on the microbial and chemical properties of ground beef. The addition of SN, SE and BCE to BNC films strengthened the matrix network and improved the mechanical properties of the films. The SN120 treatment (BNC film immersed in 120 ppm SN solution) effectively improved the redness of the samples. The results also showed that the ground beef samples covered with BNC film immersed in SE10BCE5SN30 had the lowest microbial load (more than 3.5 log10 cycle reduction compared to the control) and the lowest oxidation rate (60% reduction compared to control). Consequently, considering the health concerns regarding nitrosamine compounds, the use of natural compounds such as SE and BCE in BNC films can reduce the amount of SN required in meat products.
Food Packaging
Negar Nikfarjam; Roghayieh Razavi; Mehran Moradi; Rahim Molaei
Abstract
Despite the relatively short history of the discovery of carbon dots (C-dots) and the development of their applications, methods for producing nanodots based on green chemistry have consistently attracted the attention of scientists. In this study, green C-dots were synthesized from onion juice using ...
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Despite the relatively short history of the discovery of carbon dots (C-dots) and the development of their applications, methods for producing nanodots based on green chemistry have consistently attracted the attention of scientists. In this study, green C-dots were synthesized from onion juice using a simple hydrothermal method (200°C, 4 hours), and their optical properties, particle size distribution, and morphology were subsequently evaluated. The antibacterial activity of C-dots was assessed against pathogenic bacteria Escherichia coli (Gram-negative) and Listeria monocytogenes (Gram-positive), with minimum inhibitory concentrations of 8 mg mL-1 and 4 mg mL-1, respectively. Furthermore, the synthesized C-dots were incorporated into nanocellulose using an ex-situ method to produce modified bacterial nanocellulose (BNC) films with both antimicrobial and ultraviolet (UV) protective properties. The carbon dot-embedded nanocellulose demonstrated enhanced UV-blocking capabilities and greater inhibitory activity against Gram-positive bacteria compared to Gram-negative bacteria, highlighting its potential as a promising nano-biomaterial for food packaging applications.
