Maria do Socorro Rocha Bastos

Avaliação de parâmetros de qualidade físico-químicos de polpas congeladas de acerola, cajá e caju

This work was conducted to study the quality of frozen fruit pulps of cashew apple, yellow mombin and acerola produced by enterprises from Paraiba and Pernambuco States (Brazilian northeastern region), in order to verify if they are according to Brazilian regulatory laws. The mean values for pulps from both states were: a) cashew apple: pH 4.11; soluble solids = 9.8°Brix; acidity in citric acid = 0,39%; reducing sugars = 5.74%; ascorbic acid = 162.89mg/100g. b) yellow mombin: pH = 2.50; soluble solids = 7.5°Brix; acidity in citric acid = 1.09%; reducing sugars = 2.70%; ascorbic acid = 8.87mg/100g. c) acerola: pH = 3.05; soluble solids = 6.50°Brix; acidity in citric acid = 1.04%; reducing sugars = 3.20%; ascorbic acid = 989.51mg/100g. The result revealed that 68.2% of yellow mombin pulp samples and 59.1% of cashew apple pulp samples were found in disagreement with the QIS juice of these fruits. Concerning to acerola pulp, 40,7% of samples were also in disagreement with the required standard, according to Brazilian legislation. Such findings indicate the necessity to set up QIS for yellow mombin and cashew apple pulps in order to offer good quality products to consumers.

Efeito da aplicação de enzimas pectinolíticas no rendimento da extração de polpa de cupuaçu

Brazil displays an richness fruits varieties, many of which occur in the warmer north and northeastern regions of the country. The exotic ¾flavored cupuassu is of particular interest for its importance on the markets in southeastern Brazil and Europe. The pul and the pits constitute industrial raw material of significant potential. As object of studies in the area of nectar production, the pulp of the cupuassu is more commonly used for manufacturing ice cream, jam, mash and canned pulp. However, the pulp and the pit adheres very tighty to each other, their separation is done manually with the aid of domestic utensils such as spoons , scissors and knives, yielding rather small amounts of pulp for further processing. In order to increase the yield during the extraction process, two commercial pectinolitic enzymes (Citrozym L and Rohament PL) in concentrations of 100, 300, 500 and 750 ppm were added to the total pulp. The final yield was compared to that obtained with the control pulp (without enzymes). The experiment was carried out at the food technology laboratories at the Embrapa Tropical Agro-Industry. With the addition of the Citrozim L, tthe yield was over 60% at concentrations of 300, 500 and 750 ppm, while with the addition of Rohament PL the yield attained values between 43 and 57% at these same concentrations. The yield of the control sample was 44% for Citrozym L and 41% for Rohament PL. In conclusion, the use of enzymes with the purpose of increasing the yield of cupuacu pulp during extraction is a viable alternative, and at 300 ppm or more the yield obtained is approximately 60%.

Peptide profile of Coalho cheese: A contribution for Protected Designation of Origin (PDO).

Coalho cheese of Ceará and the Jaguaribe region of Brazil has been studied to determine its peptide profile. Peptides generated by the action of peptidases upon cheese proteins were separated by reverse-phase HPLC to give 28 fractions. Peptide sequencing after MS/MS fragmentation enabled the identification of 116 different peptides; 74 of them originated from β-casein, 4 from βA2-casein, 4 from βA3-casein, 25 from αS1-casein, 5 from αS2-casein, and 4 from κ-casein. Phosphorylated peptides were identified, one from αS1-casein and 17 from β-casein. Other reports on the bioactivity of casein-derived peptides have shown that the β-casein peptide (193-209) exhibits immunomodulatory, antimicrobial and antihypertensive activity. The peptides β-casein (58-72), β-casein (193-202), αs1-casein (85-91), αs1-casein (1-9), as well as αs2-casein (189-197) have antihypertensive activity. The fragment αS1-casein (1-23) is an immunomodulatory and antimicrobial peptide. These results can be a marker to determine the authenticity of this Brazilian cheese.

Novel polyurethanes from xylan and TDI: Preparation and characterization

ABSTRACT Xylan is a hemicellulose, which is found abundantly in nature. In this work, a novel polyurethane was developed involving xylan and tolylene-2,4-diisocyanate (TDI). Polymer synthesis was achieved through conventional heat or microwave-assisted reaction in dimethyl sulfoxide. Because xylan has multiple OH groups on each polymer chain, the TDI/xylan molar ratio had to be adjusted to produce a soluble polymeric product. The reaction products were characterized by 13C NMR, FTIR, thermogravimetric analysis, and differential scanning calorimetry. The xylan polyurethane was shown to exhibit improved thermal stability over xylan.