Practical experiments enhance students' understanding of basic concepts and promote deep learning experiences in chemistry. The smartphone application of Lab4Chemistry was utilized to replace colorimeters with smartphone camera sensors. Low-cost and readily available materials, including anthocyanin (fresh red cabbage) and common kitchen…

In the course of combining the Sustainable Development Goals (SDGs) with the science education curriculum, the relevance of the micro- and macroalgae in education is based on the biotechnological future-oriented significance and the ever-growing trend toward plant-based nutrition. So, the micro- and macroalgae are finding their way onto the food…

Red onion, "Allium cepa," juice can dye a cloth sample green upon the addition of alum, aluminum potassium sulfate, and this sample can turn red when subjected to an acidic solution. When the red-colored sample is washed with a neutral or alkaline aqueous solution, its color turns green again. These experiments illustrate color changes…

Light spectrum dispersion is an exciting subject in science because of its beautiful atmospheric colour phenomenon which attracts students. However, to see the phenomenon is not easy since it needs a spectrometer, which is commonly expensive. Therefore, the present study aims to describe a low-cost spectrometer for investigating lighting spectrum…

Stimulating interest in science at an early age is important for STEM education. This work details an educational activity utilizing the anthocyanins found in butterfly pea flowers ("Clitoria ternatea"). This activity was developed for use in official classroom settings, online, and/or at-home with parental or educator guidance. Primary…

A quantitative titration of the amount of magnesium hydroxide in milk of magnesia using only items purchased in grocery and retail stores is reported. Either vinegar or a solution of food grade citric acid serves as the titrant, while food dyes advertised as being extracted from natural sources provide the end-point indicator. An inexpensive,…

In light of the COVID-19 pandemic situation, the separation of the primary colors of ink markers and food coloring was performed using a simplified column chromatography setup at home to accomplish the educational outcome of the course. The virtual class instruction, for the students enrolled in the "Organic Techniques Laboratory"…

In light of COVID-19 in spring 2020, we developed a simple and versatile inquiry-based, laboratory-style active learning colorimetry experiment amenable to at-home quantitative analysis. In this experiment, students acquire an external calibration method using aqueous solutions of a self-selected chromophoric analyte from household products using…

Aqueous biphasic systems (ABS) composed of polypropylene glycol and carbohydrates, two benign substances are proposed to separate two food colorants (E122 and E133). ABS are promising extractive platforms, particularly for biomolecules, due to their aqueous and mild nature (pH and temperature), reduced environmental impact and processing costs.…

Instructors often present Mendelian genetics and molecular biology separately. As a result, students often fail to connect the two topics in a tangible manner. We have adopted a simple experiment to help link these two important topics in a basic biology course, using red and white onions bought from a local grocery store. A lack of red coloration…

A simple experiment designed to study mixing of a material of complex rheology in a stirred tank is described. Non-Newtonian suspensions of blue maize flour that naturally contain anthocyanins have been chosen as a model fluid. These anthocyanins act as a native, wide spectrum pH indicator exhibiting greenish colors in alkaline environments, blue…

In the last decade, our understanding of the chemistry of olive oil has dramatically improved. Here, the essential chemistry of olive oil and its important minor constituents is described and related to the typical sensory categories used to rate and experience oils: color, aroma, bitterness, and pungency. We also describe experiments to explore…

The food industry uses different additives to give foods and beverages the appearance expected by the consumer. Among them, pigments of natural origin are receiving increasing attention due to safety concerns about traditional colorants and the relevance of a healthy diet. This experiment describes the quantitative determination of the…

A chemical separation experiment can be an interesting addition to an introductory analytical chemistry laboratory course. We have developed an experiment to extract FD&C Red Dye #40 from beverages containing cranberry juice. After extraction, the dye is quantified using colorimetry. The experiment gives students hands-on experience in using solid…

Dyes aren't just for fabrics--colorants have been added to food for centuries to enhance its appearance. This monograph and teaching guide investigates both the compounds that give foods their natural color and synthetic colorants currently approved for use in foods. Problem-solving inquiry based activities involve high school level students in…