Quality of eggs sold in different commercial establishments and the study of the conditions of storage

The objective of this study was to investigate the influence of storage conditions on the physicochemical (mass, albumen height, pH, and Haugh unit) and microbiological (Salmonella spp., determination of the Total and Thermotolerant Coliforms, and Counting of the Mesophilic Aerobic Bacteria) quality of eggs. In the first experiment, a questionnaire was applied, and 33 samples of eggs were collected for the Salmonella spp analysis. In the second experiment, the eggs were collected from supermarkets, open markets, and distributors for physicochemical analysis. In the third experiment, 175 eggs were collected from the distributor, packaged in cardboard boxes lined with plastic wrapping, stored at 5 °C and 28 °C, and the physicochemical and microbiological analyses were performed at 7, 14, and 21 days of storage. In the first experiment, 100% of the samples analyzed showed no Salmonella spp. In the second experiment, it was found that the values of physicochemical parameters were in agreement with those in the literature. However, in the third experiment, the physicochemical parameter results showed statistical difference during storage and temperatures studied. Salmonella spp. were found in the samples stored at room temperature and in the refrigerated samples. Mesophilic microorganisms with values ranging from <10 CFU g- 1 (estimated) to 8.0 × 10³ CFU g- 1 and coliforms to 4 NMP.g- 1 were also found, but the presence of E. coli was not confirmed.

Prevention of enzymatic browning of yacon flour by the combined use of anti-browning agents and the study of its chemical composition

Yacon roots present functional properties because of the high levels of fructooligosaccharides (FOS), which are considered as prebiotic fibers. In addition, yacon roots are rich in phenolic compounds. During the processing of yacon, the freshly cut surface undergoes rapid enzymatic browning. Control of enzymatic browning during processing is very important to preserve the appearance of yacon flour. In this study, it was evaluated the combined effect of anti-browning agents (ascorbic acid, citric acid and L-cysteine) on the inhibition of enzymatic browning of yacon, using Response Surface Methodology. The yacon pre-treated with anti-browning agents in concentrations of 15.0 mM for ascorbic acid, 7.5 mM for citric acid and 10.0 mM for L-cysteine was used for the processing of flour. Yacon flour presented an attractive color and good sensory properties, without residual aroma. The contents of FOS and phenolic compounds obtained in yacon flour were 28.60 g.100 g- 1 and 1.35 g.100 g- 1. Yacon flour can be considered as a potential functional food, especially due to high levels of FOS, which allows for its use in formulation of various foods.

Study of the physicochemical characteristics of soursop powder obtained by spray-drying

This study aimed at contributing to the development of new foodstuffs made by soursop pulp powder obtained by spraydrying. Different concentrations of maltodextrin DE 20 (15, 30, and 45%) were added to commercial soursop pulp, which was dehydrated afterwards. The following analyses were carried out: water activity, moisture, pH, soluble solids, acidity, ascorbic acid, hygroscopicity, degree of caking, and rehydration time. The results obtained for the three powder treatments (15, 30 and 45% of maltodextrin) were, respectectively: water activity (0.19a±0.00; 0.20a±0.00; 0.18a±0.01); moisture (1.17c±0.12; 1.47b±0.05; 1.82a±0.06); pH (3.75a±0.05; 3.73a±0.06; 3.70a±0.03); soluble solids (89.67a±0.00; 89.84a±0.00; 90.00a±0.06); acidity (3.01a±0.02; 1.91b±0.03; 1.24c±0.03); ascorbic acid (18.90a±0.00; 14.48b±0.00; 11.26b±0.78); hygroscopicity (5.93a±0.40; 3.82b±0.16; 3.28b±0.38); degree of caking (78.36a±2.86; 35.38b±6.07; 24.77b4.89), and rehydration time (02.03a±0.46; 01.16ab±0.50; 0.59b±0.30). The soursop powders with 30 and 45% of maltodextrin had few significant differences in terms of physicochemical and hygroscopic characteristics, which allow us to consider the percentage of 30% of maltodextrin, in this study, as the best percentage for soursop pulp atomization.