Extension of shelf life of whole and peeled shrimp with organic acid salts and bifidobacteria

Microbiological and sensorial characteristics of treated whole and peeled shrimp from the east coast of Saudi Arabia were evaluated. Shrimp samples were treated with organic acid salts with or without bifidobacterium breve culture and stored in ice. Peeling alone extended the microbiological shelf life by four days. Treatment of whole shrimp with sodium acetate alone or potassium sorbate with bifidobacteria prolonged the microbiological shelf life by three days and increased the microbial generation time from 12.8 h (control) to 30.1 h or 31.4 h, respectively. The microbiological and sensory shelf life of peeled shrimp treated with sodium acetate was more than 17 days. Sodium acetate extended the microbial lag phase and lengthened the generation time (38.7h compared to 15.8h for the control). Micrococci and coryneforms were the predominant microorganisms in whole shrimp during storage. Treatment with sodium acetate maintained better sensory characteristics for peeled shrimp than potassium sorbate combined with bifidobacteria

Experimental design to optimization of beta cyclodextrin production from ungelatinized sago starch

The aim of this study is to produce beta cyclodextrin (β-CD) from ungelatinized, but annealed (65 °C) sago starch using cyclodextrin glucosyltransferase (CGTase). The optimization processes were conducted at three stages using Response Surface Methodology. Preliminary data have shown that the three (3) highest points for each of the studied parameters were pH, concentration of sago starch and enzyme, and also agitation. In the second stage, two level full factorial design (2n FFD) was applied to determine the significant parameters affecting the production of β-cyclodextrin. Statistical analyses showed that pH, enzyme and sago starch concentration were the significant parameters. The final stage of optimization involved the use of Central Composite Design to determine and predict the optimum yield of β-cyclodextrin. The optimum condition for production cyclodextrin was at pH 8.62 (Glycine–NaOH buffer 0.05 M), 0.65% v/v sago starch and 15% w/v enzyme concentration, where 8.43 g β-cyclodextrin/L was produced after 4 h of reaction