This study aimed to evaluate the effects of temperature, time, and thickness of tomatoes fruits during adiabatic drying process. Dehydration, a simple and inexpensive process compared to other conservation methods, is widely used in the food industry in order to ensure a long shelf life for the product due to the low water activity. This study aimed to obtain the best processing conditions to avoid losses and keep product quality. Factorial design and surface response methodology were applied to fit predictive mathematical models. In the dehydration of tomatoes through the adiabatic process, temperature, time, and sample thickness, which greatly contribute to the physicochemical and sensory characteristics of the final product, were evaluated. The optimum drying conditions were 60°C with the lowest thickness level and shorter time.

Ionizing radiation can be used for different purposes in the food industry. In this study, the effect of irradiation doses (0, 0.5, 1.0 and 1.5 kGy) on the quality parameters of long life tomatoes (Lycopersicon esculentum Mill.), was evaluated during 4 storage periods (1, 7, 14 and 21 days). The different treatments were evaluated by analysing for colour, pH, total soluble solids (TSS), total titratable acidity (TTA), ratio (TSS/TTA), hardness, total lycopene and ascorbic acid contents, weight loss and maturation stage (O2 /CO2 ratio) for all the storage periods. The tomato samples were irradiated in a Co60 irradiator and maintained at 22 °C ± 1 °C. The quality of the tomato fruits was influenced by the gamma radiation basically by making the fruits softer and not degrading the ascorbic acid and lycopene contents at the doses evaluated. The irradiation process used in the doses evaluated was promising with respect to maintaining the quality parameters of long life tomatoes.

No abstract

In order to identify products acceptance and commercialization, researchers performed sensory evaluation. The responses to these studies are ordinal categorical variables, thus, they are normally based on a hedonic scale. Generally, in sensory experiments, each judge evaluate several products and the answers given by the same judge can be classed as repeated measures. In this paper, we propose an alternative statistical analysis to consider the natural ordering and repeated measures simultaneously using proportional odds mixed models. Such models were proposed to compare the taste acceptance of two varieties of tomato, Italian and Sweet Grape, after the osmotic dehydration process. The experiment was designed in the way that each judge, randomly selected and evaluated each variety once. The results showed that the Sweet Grape presented better acceptance than Italian variety. This model allowed the predictions and estimations probabilities to be calculated for each of the response categories according to each variety. Practical applications Tomate is a product highly perishable and new dehydration techniques are being developed and needs to have good accepted by consumers. In this paper, we proposed an alternative statistical model to compare the taste acceptance of two varieties of dehydrated tomato, Italian and Sweet Grape. The model presented can be used in different sensorial evaluations and can help researchers to analyze ordinal categorical data, focusing on how to identify and account for specific issues arising from experimental design (such as correlated observations). The results showed that the Italian tomato was 6.89 times more likely to be classified with lower scores at hedonic scale compared to Sweet Grape tomato regardless of sex. The Sweet Grape variety has a probability of 44% (32%; 57%) of receiving score 9 and for Italian variety this happens with a probability equal of 10% (5%; 19%). In addition, the results showed no significant correlation between responses from the same judge.