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In this study, orange oil was incorporated into biodegradable polylactic acid (PLA) at various concentrations (1.25%, 1.875%, 2.5%, and 3.75% w/v) to develop potential antimicrobial food packages. Increasing orange oil concentration caused a gradual increase in the films' opacity values, making them more appropriate for packaging of foods having a potential to be affected from UV-light. Independent of orange oil concentration, the water vapor permeability of the films decreased. While orange oil incorporation did not alter thermal stability of the active films, a slight reduction in glass transition and melting temperature values was observed. The antimicrobial activity of the films was examined on the most common food-borne pathogens (E. coli, S. aureus), and it is only the film containing 3.75% w/v (PLA_3) that showed an inhibitory activity on both microorganisms. Finally, the shelf life of the chicken fillets packed with neat PLA (PLA_0) and PLA_3 films was compared, and PLA_3 increased the shelf life up to day-9. Highlights * Various concentrations of orange oil were used to develop active polylactic acid (PLA) films. * Opacity of the films increased with increasing oil concentration. * Incorporation of orange oil resulted in decreasing water vapor permeability. * Orange oil worsened both tensile strength and elongation at break of films. * PLA_3 inhibited the growth of microorganisms and extended the shelf life of chicken fillet. KEYWORDS antimicrobial package, chicken fillets, orange oil, polylactic acid (PLA), shelf life, 1 | INTRODUCTION Since non-biodegradable plastics causes many questions regarding their environmental impact, attention has shifted towards eco-friendly and low-pollution alternatives like bio-based polymers. These polymers can be grouped into [...]

Honey has great benefits to humans, both as medicine and food. It contains glucose, fructose and water in addition to small quantities of proteins, minerals, organic acids, and vitamins. Vacuum cooling is a rapid cooling technique based on the principle of evaporation, which lowers the boiling point of water based on the vacuum pressure inside a cooler room. A prototype vacuum-cooling jet water system was used to process the honey. Raw honey obtained from the forests of Riau was used in the present study. This study aimed to determine the effect of jet water vacuum cooling with variations in volume (V/V), capacity (12.5%, 25%, and 50%) on the quality of honey (Apis dorsata Fabricus) to accelerate the cooling process and preserve product quality. The cooling mechanical analysis parameters reviewed included the processing time and the lowest maximum pressure. The parameters of the quality of honey observed included moisture content, viscosity, density and total dissolved solids. As a result, the vacuum cooling process can suppress damage to the quality of honey owing to the heating process. At the cooling time and lowest maximum pressure value, the mechanical aspects of the water jet system vacuum cooling process showed the maximum results. The water contents of 12.5% (V/V), 25% (V/V) and 50% (V/V) filling were 13.69%, 12.89%, and 14.25%, respectively. The viscosities at 12.5% (V/V), 25% (V/V) and 50% (V/V) filling were 2.604 Pa.s, 2.355 Pa.s, and 1.644 Pa.s, respectively. Density with 12.5% (V/V), 25% (V/V) and 50% (V/V) filling were 1.52 g/cm3,1.53 g/cm3 and 1.50 g/cm3, respectively. Total dissolved solid values of honey with 12.5% (V/V), 25% (V/V), and 50% (V/V) fillings were 78.16%, 78.16% and 77.66%, respectively. Water jet vacuum cooling with a 25% chamber volume capacity accelerates honey with the best total dissolved solids, density and moisture content. Vacuum cooling can be used to improve product quality, shorten handling time, extend product shelf life and improve security. Key words: honey, pressure, vacuum cooling, density, moisture content, viscosity, INTRODUCTION The giant honeybee Apis (Megapis) dorsata Fabricus is widespread in Indonesia [1]. Honey is a great benefit to human beings both as medicine and food. It contains glucose, fructose, [...]

Rural people have the indigenous knowledge of processing and preserving food to ensure household food security during times of food scarcity. Although indigenous knowledge plays an important role in ensuring household food security for many rural households, it is often overlooked as a solution to address food and nutrition insecurity. The main objective of the study was to identify and document indigenous food preservation and processing techniques used by rural women to ensure household food security. Qualitative data were collected from small-scale farming households in seven villages through focus group discussions, individual interviews, and observations. The researchers adhered to ethical considerations (approvals, permissions with the relevant authorities, consent from participants, their privacy, anonymity, and confidentiality) throughout the research process. Data were analysed using thematic content analysis. The results indicate that sun-drying and fermentation were the most commonly used methods for food preservation, while the most prevalent methods used for processing vegetables (merogo) involved cooking, mashing, pelleting and sun-drying. Crops, such as mung beans, bambara groundnuts and sorghum are threshed and winnowed to remove all impurities. The seeds, which are to be used in the next planting season, are treated with aloe ash to prevent pest infestation. Indigenous fruits are gathered from the wild and eaten as snacks. Indigenous dried vegetables (merogo) and fermented marula beer were sold to generate income that is used to buy other basic food items. The paper concludes by highlighting the existing indigenous knowledge that rural households demonstrate in terms of food processing and preservation. Given the existing knowledge and the commonly used methods for preserving and processing food, it is crucial to create awareness regarding ways of retaining nutrients during food preservation and processing to ensure availability and proper utilisation of indigenous foods for household food security purposes. The study recommends that these methods, including ways of retaining nutrients, be documented and made easily accessible for rural households to use now and in the future for ensuring household food and nutrition security. Therefore, there is a need for agricultural and food security policies to embrace, adopt, promote and adapt indigenous knowledge and technologies to address food security. Key words: indigenous knowledge, food preservation, food processing, food security, indigenous food preservation, INTRODUCTION Indigenous knowledge is an important resource for many poor, rural societies and it remains with them even when other resources decrease. An indigenous knowledge system focuses on the ways [...]

Leafy vegetables play a crucial role in the human diet providing numerous nutrients and health benefiting compounds. Leafy vegetables like collard (Brassica oleracea var. acephala) and black nightshade (Solanum nigrum l.) are commonly consumed leafy vegetables in Kenya. However, their high perishability and short shelf life (usually 1-2 days at ambient temperature) limits their utilization resulting in significant high postharvest losses. This study assessed the effect of harvest stage and nitrogen fertilization on the postharvest shelf life of collard and black nightshade. Experiments were conducted at Kabete field station, University of Nairobi, using collard and black nightshade. Field experimental layout was a 4 x 3 factorial arrangement in randomized complete block design with three replicates. Factors were nitrogen levels and harvest stage. Four levels of nitrogen (0, 30, 60 and 90 kg N/ha) were applied on black nightshade and (0, 55.5, 111.1 and 166.6 kg N/ha) in collard where 0 kg N/ha was the control. Collard and black night shade were harvested at three harvest stages: 4 weeks, 6 weeks and 8 weeks after transplanting. The harvested vegetables were kept at ambient room condition (20 [degrees]C, 55% relative humidity). Data collection was performed daily for quality related parameters which included color change, wilting index and cumulative weight loss. Results show that there was a progressive deterioration in quality of the collard and black nightshade with storage time regardless of harvest stage and nitrogen level. Harvesting at 8 weeks after transplanting resulted in longer shelf life in collard (three days) and black nightshade (two days) when compared to harvesting at 4 weeks or 6 weeks after transplanting. Collard and black nightshade showed reduced hue angles over storage time at different harvest stages. Black nightshade subjected to 90 kg N/ha and harvested at 4 weeks after transplanting had the highest wilting index of 33%. The highest cumulative weight loss of 29% was recorded in collard that were harvested at 8 weeks after transplanting. Black nightshade subjected to 90 kg N/ha and harvested at 6 weeks after transplanting showed the best color at a hue angle of 145[degrees]. Overall, harvesting at 8 weeks after transplanting resulted in the longest shelf life of both black nightshade and collard. These results show that low application of nitrogen fertilizer in black nightshade (30 kg N/ha) and in collard (55.5 kg N/ha) had minimal effects on weight loss and wilting and resulted in good keeping quality. Key words: Black nightshade, Collard, Harvest Stage, Nitrogen nutrition, Shelf life, INTRODUCTION Horticulture is the fastest growing subsector of agriculture in Kenya. It contributes to poverty alleviation, food security and generates job opportunities along the food value chain [1]. Leafy vegetables [...]

Red Knots (Calidris canutus rufa) are long-distance migratory shorebirds that fly from the Arctic to the southern tip of South America. They stop over in a few places with high concentrations of trophic resources that act like population bottlenecks. At a population level, unavailable resources during a stopover can have catastrophic consequences. Because of their importance, these sites must be managed and conserved. On their northward migration, Red Knots stop over on Peninsula Valdes (Patagonian Argentina) between March and May, during which we surveyed them every year between 2006 and 2013. This peninsula is surrounded by 2 gulfs where the Blancas, Fracasso, Conos, and Sarmiento Beaches were monitored (in the San Jose Gulf), and the Colombo Beach (in the Nuevo Gulf). We recorded encounter-reencounter data of individually tagged Red Knots through telescopes. To evaluate Red Knot site fidelity, we used the Standardized Site Fidelity Index, which was calculated for individual beaches and grouping the beaches by gulf. In order of importance, Red Knots were more faithful to Blancas, Fracasso, and Colombo Beaches. When we grouped beaches, site fidelity was greater in the San Jose Gulf, which can be linked to reports of its greater food supply. The use of this index is a useful and powerful tool to make decisions or propose management strategies. Received 19 September 2019. Accepted 1 March 2022. Key words: conservation, encounter-reencounter, management, shorebirds, stopover. Los playeros rojizos son aves playera.s migradoras do larga distancia, que vuelan desde el Artico hasta el sur de Sudamcrica. Realizan paradas migralorias en escasos sitios con elevada oferta trofica, los cuales actuan eomo cucllos de botella poblacionales. Se han registrado eonsccuencias calastroficas a nivel poblacional cuando los rccursos no estuvieron disponibles durante una parada migratoria, por lo que diehos sitios deben ser manejados y conservados. En su migracion al norte, entre los mcses de marzomayo se detienen en Peninsula Valdes (Patagonia Argentina), dondc se realizaron monitoreos todos los afios entre 2006-2013. La peninsula esta rodeada por 2 goltbs donde las playas Blaneas, Fracasso, Conos y Sanniento fueron monitoreadas en el Golfo San Jose y playa Colombo en el golfo Nucvo. Se tomaron datos de encuentro-reeneuentro de playeros rojizos anillados individualmcnte en todas las playas utilizando telescopios. Para evaluar la fidelidad al sitio por parte de los playeros rojizos, se utilize el indiee Estandarizado de Fidelidad al Sitio. Este indiee se calculo para cada playa y agrupando las playas scgun el golfo donde se ubican. En orden dcereciente, los playeros rojizos fueron mas fielcs a las playas de Blaneas, Fracasso y Colombo. Cuando las playas se agruparon por golfo, la fidelidad al sitio rue mayor en el golfo San Jose que en cl golfo Nucvo, la cual puedc cstar relacionada con la reportada mayor oferta trofica en este golfo. La aplicacion de estc indiee es una herramienta litil y poderosa para tomar decisiones o proponer estrategias para su manejo. Palabras clave: aves playeras, conservacion, encuentro y reencuentro, cscala migratoria, manejo., Red Knots (Calidris canutus rufa) are longdistance migratory shorebirds that fly between the Arctic tundra and Tierra del Fuego (in southern South America), where they spend the austral spring and [...]

This personal essay explores the relationship between food preservation and cultural preservation. While food preservation requires sterility, sweetness, and unblemished specimens, folklorists must contend with the ways that folklore can be ugly, unethical, and messy. Narratives of clean food and rural idylls often elide structures of economic and social violence--in this case, the prison industrial complex. National and family narratives grapple with a yearning for nostalgia, while reciprocal ethnography can open a debate among practitioner and researcher that does not fit neatly into ajar., I have a walk-in closet in my home and it is filled from top to bottom with kitchen equipment. To the right, I store bulk beans, packets of dried seaweed, [...]

Essential oils (EOs) obtained from a wide variety of plants have become popular with increased scientific interest as potential natural agents for food preservation. Two concentrations of rind EOs (400 mg/ml and 200 mg/ml) from three species of citrus fruit; Citrus sinensis (Sweet orange), Citrus limon (Lemon), and Citrus aurantifolia (Lime) were used to treat fresh chicken meat inoculated with Escherichia coli ATCC 25922, Salmonella typhi ATCC 20971 and Salmonella enterica ATCC 14028 to evaluate their protective abilities on bacteria-contaminated meat The EOs were extracted from the ground rinds by hydro-distillation. Alongside the EOs, sodium nitrate (Na[NO.sub.3]) was used as a positive control preservative. A viable count was carried out to determine the bacteria load reduction on the inoculated fresh chicken meat. After 24 hours of treatment, the results showed that the EOs had no adverse effect on the physical attributes of the meat: the color and smell of the chicken meat were unaltered compared with the negative control (None EO and Na[NO.sub.3] treated meat) that showed evidence of putrefaction through color change and foul smell. The two- lime rind EOs concentrations used to treat the Escherichia coli ATCC 25922 inoculated meat reduced the viable count of the organism by 7.9 log compared to the Escherichia coli ATCC 25922-inoculated meat which received no rind EOs or Na[NO.sub.3] treatment. Other results showed that sweet orange (SO) rind EOs (400 mg/ml and 200 mg/ml) treatment of meat inoculated with Salmonella enterica ATCC 14028 had similar but mild preservative effects as both treatments reduced the log of the bacteria by 1.1 and 0.8, respectively. In comparison with Na[NO.sub.3], the EOs treatment had a significant (p Key words: Bacteria, Chicken meat, Citrus rind, Essential oil, Preservation, Sodium nitrate, INTRODUCTION Food, either raw or processed, should be wholesome and free of contaminants. Notwithstanding, foods are often exposed to physical, chemical, or biological contaminants that can cause undesirable changes, thus [...]