Effect of Antigonon leptopus extract in corn starch-glycerol based film as colourimetric indicator film for monitoring fish freshness

A colourimetric indicator can be used to test the freshness of fish in a rapid, straightforward and non-destructive manner. Anthocyanin, a natural dye found in Antigonon leptopus flowers, has a sensitive colour reactivity to a wide range of pH levels and can be made into colourimetric indicator films on a laboratory scale, making it a viable replacement for artificial dyes. The study's purpose was to see how the concentration of A. leptopus extract affected the colourimetric assessment of fish freshness. Ethanol was used to extract anthocyanin from A. leptopus. FTIR and pHrespond spectroscopies were used to characterise the extracts. Colourimetric indicator films were developed to assess fish freshness by incorporating A. leptopus extract into a corn starch-glycerol matrix via the solution casting method, with concentrations of 10%, 30% and 50%, respectively. The effect of A. leptopus extract on visual aspects, thickness, morphology, FTIR spectra, UV-Vis spectra and colour responses was analysed. Microbial analysis, TVB-N contents, firmness, and pH of the fish samples were analysed after storage. The colour of the original films became darker as the extracted content increased. There was no significant (p>0.05) effect of A. leptopus extract on film thickness. SEM micrographs revealed that the composite films had homogeneous and whitish granules on the surface and that increasing the A. leptopus extract concentration caused the films to become rougher. FTIR and UV-Vis spectroscopies showed successful binding between A. leptopus extracts and corn starch-glycerol film. With increasing pH, the colour change of the films exposed to pH = 3-11 solutions was no significant difference due to improper storage. An increase in the microbial population, TVB-N content and pH was observed over the storage period as a result of fish deterioration. Colour changes were also identified in the film which became darker. Overall, colourimetric indicator film with 50% A. leptopus extract was found to be the optimal formulation since it had the highest values in ∆E* during progressive spoilage of fish

Assessing the impact of spent coffee ground (SCG) concentrations on shortbread: A study of physicochemical attributes and sensory acceptance

Currently, every 1 kg of instant coffee produced results in 2 kg of wet SCG, accounting for 45% of total annual production. Instead of being wasted and causing environmental issues, SCG can be utilized for its potential to create valuable products with added value. This study explores the underutilized potential of spent coffee grounds (SCG) as a functional ingredient in shortbread biscuits, with the aim of improving their nutritional value and reducing waste in the coffee industry. In this study, six different shortbread formulations were developed using various concentrations of SCG powder (ranging from 0 to 10%). The samples were subjected to physical, sensory, proximate, and chemical analyses to assess their storage quality, physicochemical properties, and sensory acceptability. The results showed that the SCG-containing shortbread had higher moisture, protein, ash, fibre, total phenolic content, and antioxidant activity than the control sample, with the 10% SCG shortbread proving to be the most desirable in terms of aroma and hardness. Overall, this study highlights the potential of SCG as a valuable source of bioactive compounds in innovative cookies, offering opportunities for the utilization of industrial by-products, reducing waste, and improving nutritional properties