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The purpose of this research is to identify and investigate some natural dyes with halochromic properties for potential use as food spoilage indicators to reduce waste and curve the negative effects of food borne diseases.

Exactly 10 potential dye-yielding plants were selected based on their colour (mostly purple, red, maroon and pink). Solvent extraction was used to extract the dyes and pH differential method was used to determine the concentrations of anthocyanin in the extracted dyes. Different concentrations of hydrochloric acid and sodium hydroxide (0.1 M, 1 M and 2 M) in drops and in excess as acidic and basic solution, respectively, were used to test the halochromicity of the extracted dyes. Methyl red (a synthetic dye) was used as a reference standard/control. The pH of the dyes was recorded before and after addition of both NaOH and HCl solutions.

Five out of the 10 dyes extracted (labelled as dye A–E for Ti plant (green Cordyline fruticosa), coleus (Coleus blumei), paper flower (Bougainvillea glabra), painted nettle (Palisandra coleus) and purple heart (Setcresea purpurea), respectively, were found to be halochromic (even at low doses) by changing its colour when exposed to both acidic and basic solutions. While other dyes labelled F–J for red acalypha (Acalypha wilkesiana), golden shower (Cassia fistula), golden dew drop (Duranta repens), wild sage (Lantana camara var Aculeata) and pink oleander (Apocynaceae Nerium oleander), respectively, were either completely insensitive to the solutions in drops, slightly sensitive at high doses or the colour change is insignificant. Although some dyes were found to be more sensitive than others but in most cases, the colour changes in halochromic dyes were more stable in acidic conditions than in basic making it more sensitive to the basic than the acidic solution with the exception of dye A and E (to some extent) which was sensitive to both acidic and basic solution. The anthocyanin contents of dye A–J were found to be between the range of 2.28–10.35 mg/l with dye E having the lowest and dye J with the highest anthocyanin concentration, respectively. The initial pH of all the dyes falls within the range of 4.8–7.3 with most found within the acidic range.

Halochromic dye research studies are still at the infancy stage in developing world despite the vast available and abundant potential natural halochromic dye-yielding plants. The study explored this area of research and gives an opportunity for the development of smart packaging for pH-sensitive foods using natural dyes as an alternative to conventional synthetic dyes to reduce cost and also curve the negative effect of synthetic dyes as well as food borne diseases.

The purpose of this study is to successfully apply ultrasonic waves for the quick extraction of flax seed gum from flaxseed hull or whole seed and compare it to the standard technique of extraction.

The effect of the heating source, extracted time, temperature and pH of extracted solution on the extraction was studied. The obtained gum is subsequently used for silk screen printing on cotton, linen and viscous fabrics. Rheological properties and viscosity of the printing paste were scrutinized in the current study to get a better insight into this important polysaccharide. The output of this effort aimed to specify the parameters of the processes for printing textiles to serve in women’s fashion clothes by applying innovated handmade combinations of Islamic art motives using a quick and affordable method. Seven designs are executed, and inspiring from them, seven fashion designs of ladies’ clothes were designed virtually by Clo 3D software.

The result recorded that the new gum has excellent printing properties. In addition, they have better rheological properties, viscosity, chromatic strength and fastness qualities, all of which could help them in commercial production.

Flaxseed and three different fabric types (Cotton, Linen and Viscous) were used.

Synthesis of a new biodegradable thickener from a natural resource, namely, flaxseed, by applying new technology to save time, water and energy.

Synthesis of eco-friendly biodegradable thickener and used in textile printing alternative to the synthetic thickener.