Abstract A new approach to meat color and shelf-life assessment is reported here for hamburgers mixed with goji berry. Samples with powdered or aqueous extract of goji berry were monitored, compared with hamburgers without the additive for ten days and its L*, a* and b* properties were determined by computer vision using a homemade setup. Noteworthy results, in particular the luminosity, for all samples with goji berry – only or with salt and pepper – were perceived, and predictive mathematical models for these food mixtures are here presented. The addition of goji berry in hamburgers, pioneered in this study, present advantageous characteristics both in terms of storage time and a positive effect on human health owing to the polyphenols in the natural additive. This study also offers insights into a low-cost and reliable method for the quality control of meat with potential application in the food industry.

The Rancimat and accelerated stove tests were used to determine the oxidative stability of B100 biodiesel mixed with synthetic antioxidants. The predictive equations, with process variable, were obtained by applying a simplex-centroid design. Regardless of the antioxidant used, all assays carried out with the accelerated stove test presented storage time longer than 177.88 d, the greatest value obtained by applying the Rancimat test. The t test, applied to the parameters containing the process variable, showed a statistically significant difference (at the level of 5%) between the methods used.