Carbon footprint of recycled paper

Industrial production of pulp and paper is an intensive consumer of energy, natural resources, and chemicals that result in a big carbon footprint of the final product. At present companies and industries aspire to calculate their gas emissions into the atmosphere in order to afterwards reduce atmospheric contamination. One of the approaches allowing to increase carbon burden from the pulp and paper manufacture is paper recycling. The general purpose of the current paper is to establish methods of quantifying and minimizing the carbon footprint of paper. The first target of this research is to derive a mathematical relationship between virgin fibre requirements with respect to the amount of recycled paper used in the pulp. One more purpose is to establish a model to be used to clarify the contribution of recycling and transportation to decreasing carbon dioxide emissions. For this study sensitivity analysis is used to investigate the robustness of obtained results. The results of the present study show that an increasing of recycling rate does not always lead to minimizing the carbon footprint. Additionally, we derived that transportation of waste paper throughout distances longer than 5800 km has no sense because the use of that paper will only increase carbon dioxide emissions and it is better to reject recycling at all. Finally, we designed the model for organization of a new supply chain of paper product to a customer. The models were implemented as reusable MATLAB frameworks.

Survey of aflatoxins in tomato products

Tomatoes are highly susceptible to fungi contamination in the field, during transportation, processing, and storage. Aspergillus flavus and Aspergillus parasiticus have been isolated from tomatoes and tomato products, and both fungi species can produce aflatoxin, mycotoxin with hepatotoxic, carcinogenic, teratogenic, and mutagenic effects on all animal species tested so far. In order to verify a possible aflatoxin contamination of tomato products commercialized in Brazil, 63 samples of tomato products (pulp, paste, purée, ketchup, dehydrated tomatoes, and dried tomatoes preserved in oil) produced in 5 Brazilian states and 1 imported sample (ketchup), totalizing 29 brands, were analyzed by thin layer chromatography. The analytical method showed an average recovery of 86% for all aflatoxins at two spiking levels. The limits of detection for the aflatoxins B1, B2, G1, and G2 varied with the type of the product ranging from 2 to 7 µg/kg. Aflatoxins were not detected in any evaluated sample indicating that they did not pose a risk to human health since there was no invasion of raw materials by toxigenic fungi or no conditions for toxin production.

Quality of minimally processed guava with different types of cut, sanification and packing

The purpose of this project was to evaluate the sanitization effect on the quality of minimally processed guava. Initially, research was carried out with consumers in a supermarket to verify preferences of packaging for guava. Following this, the guava cv. Paluma underwent two sanitization sequences using dehydrated sodium dichloroisocyanurate compound, in 50 ppm concentration, sanitization prior to (S1) and after (S2) being cut; removal of excess water; conditioning in PET packaging and PSPVC and storage at 3 ºC ± 1 ºC. Physicochemical analysis - [pH, total soluble solids (SST), total labeled acidity (ATT), ascorbic acid (AA), total sugars (AT) and reducers (AR)], textural sensorial and microbiological analyses were used to monitor the quality of the products. The consumers preferred the guava cut in halves with pulp and packed in PET, although this packaging promoted condensation of water vapor on the inner surface of the lid, compromising the appearance of the product. The two sanitization sequences and the two kinds of packaging did not significantly affect the pH, SST, ATT, SST/ATT, texture and AA values. The AT and AR tenors increased significantly in the MP guavas stored in the PSPVC package. Both sanitizations were efficient in the bacterial control of the indicators of the hygienicsanitary conditions, although the S1 sanitization proved to be more efficient in the control of autochthonous aerobic microbiota (aerobic mesophylic microorganisms). It can be concluded that guava cv. Paluma packed in PSPVC can be conserved for 6 days when stored at 3 ºC.

Carbohydrate composition of ripe pineapple (cv. perola) and the glycemic response in humans

Brazil is the third largest producer of pineapple (Ananas comosus) and the market for fresh pineapple is sustained by the Hawaii and Perola cultivars. In this work the Perola cultivar was divided into three main parts, shell, core and pulp, for characterization. Moisture in the pulp was higher (between 10 and 15%) than in the shell and core. The amount of protein was higher in the core (35%) than in the pulp and shell. Perola contained relatively low concentrations of total ascorbic acid in the edible parts, although higher levels of ascorbic acid in the shell. Citric acid corresponded to almost 60% of the total organic acids. The total soluble sugars [~7-12% (FW)] were predominantly sucrose, fructose and glucose. The core had almost twice as much total sugar (12%) than the pulp (6.8%). The amount of insoluble dietary fiber was around 1%, and the soluble fiber was less than 0.1%. The pulp showed the highest concentration of polyphenols (0.49%) and antioxidant activity (33 µmol.g-1) out of the parts. The consumption of the pineapple pulp or core produced a high glycemic index (~93%), but considering the glycemic load, this fruit can be considered as low dietary.