Pineapple Peel Powder Research Articles

Biosorption of Toxic Heavy Metals on Sawdust

The present investigation deals with the biosorption of Zn2+, Cr3+, and Pb2+ in the liquid phase on the surface of zinc sequestering bacterium VMSDCM (accession no. HQ108109) cells immobilized on pineapple peel powder particles (the term sawdust has been used for immobilized microorganisms). In batch studies, the biosorption data design and regression model for predicting the relationship between the metal ion and their biosorption capacity used were Minimum Run Res V Design and quantitative ion character activity relationship (QICAR), respectively. The values of qmax calculated by the Langmuir isotherm were found to be in increasing order of Cr3+ < Zn2+ < Pb2+. The results of the present investigation showed that the pH and contact time played an important role in the removal of Zn2+ from the liquid phase. In case of Cr3+, the significant independent parameters associated with metal ion removal were the initial concentration of the metal ion and the pH. The important independent parameters for Pb2+ removal were the temperature (°C) and pH, respectively. In QICAR modeling, among all six physico‐chemical characteristics only the ionization potential (eV) played a negative role in the biosorption of metal ions. The rationale behind the inverse relationship between the removal of metal ions and eV was the variation of the corresponding covalent index. The rest of the remaining five physico‐chemical properties showed that regression models fitted quite well and were characterized by high values of the linear regression coefficient (R2), adjusted R2, and low values of the error function (χ2). In the present work, it was concluded that the immobilized cells of sawdust can be a suitable alternative for the removal of heavy metal ions from the liquid phase. The initial concentration of all the metals was kept at 50 mg L−1 each in the liquid phase. The residual concentrations of Zn2+, Cr3+, and Pb2+ after the biosorption were 0.4, 1.2, and 0.2 mg L−1, respectively.

Carboxymethyl Cellulose from Pineapple Peel: Useful Green Bioplastic

The pineapple peel cellulose can be convert to carboxymethyl cellulose (CMC) by etherification. The pure cellulose from pineapple can be prepared by refluxing of pineapple peel powder with 0.5 M HCl and 1 M NaOH solution at 90°C for 1 h and 2 h, respectively. Then, the solid material was bleached with calcium hypochlorite. The pure cellulose was soaked in mixed solution between isopropyl alcohol and NaOH for 12 h. After that, it was reacted with cholroacetic acid at 55°C for 6 h. The optimum condition for carboxymethylation was cellulose 5 g, cholroacetic acid 13.0 g and 40%w/v NaOH 50 mL. The optimised product had a DS of 0.50 and used as constituent in bioplastic. The application of pineapple peel bioplastic probably is green packaging of dehydrated materials.

Formulation and Sensory Acceptance of Cereal-Bars Made with Almonds of chichá, sapucaia and gurguéia Nuts

The new trends for consumption of healthy, innovative and practical food have led to the growth of cereal-bar market in recent years. In the native Brazilian flora, there are some species still unknown, which have high potential for nut market, such as chicha, sapucaia and gurgueia. The aim of the present study was to produce cereal bars from those nuts, supplemented with pineapple peel. Cereal-bars made with chicha, sapucaia and gurgueia nuts were prepared by us- ing three formulations as follows: A, B and C, respectively, which differ according to the proportions of vegetal fat and pineapple peel powder used in the processing system. It was verified, by using the global appearance parameter, that among the different formulations tested, formulation B obtained the highest rate for the attribute 'acceptability'. Chicha and sapucaia cereal-bars were, in general, more accepted than gurgueia nut cereal-bar. It was observed that the use of al- monds of chicha, sapucaia and gurgueia nuts, and pineapple peel is feasible to produce nutritional cereal-bars.