Search

Active packaging is a promising form of modern food packaging with great potential; economically, environmentally and generally, as it gives a lot of health benefits. Active and smart packaging is made by incorporating suitable colour indicators into food package matrices and applying a bio switch concept to inhibit the spoilage and the pathogenic microorganisms. The main objective of this study are to evaluate starch-based hydroxyethyl cellulose (HEC) the best formulation of methyl red and bromothymol blue that can react with wide pH ranges and the effect of the smart film indicator incorporated with methyl red and bromothymol blue. A solution casting method was used in the film preparation and colour indicators were incorporated before casting. The ratio of 50:50 methyl red and bromothymol blue showed the best formulation which can react with a wide range of pH buffer 1 to 13 compared to ratio 20:80 and 80:20 of methyl red and bromothymol blue. The ratio of 50:50 methyl red and bromothymol blue were then selected to be incorporated into the film to see the effectiveness of the indicator film in order to detect the changes of pH.

The present study aimed to characterize the agricultural residues of sugarcane bagasse {SB} and pineapple core {PC} for the use in immobilization of Lactobacillus rhamnosus NRRL 442. Using Standard Official Methods, SB and PC were found to contain approximately equal amount of nutrition content. The nutrition contents found include: 2.7-2.8 % of protein, 9.8-10 % of crude fiber, and 0.3-0.5 % of fat. On the other hand, SB demonstrated relatively higher solution holding capacity of 9.42 ± 2.3 g/g dry size sample than that of 6.04 ± 2.1 g/g dry size sample in PC. Under screening electron microscope, the fiber of SB has a flat and even surface; in contrast, the fiber of PC has a rough and overlapping surface which may promote the attachment or cell holding capacity during the immobilization process. However, the viability tests after cells immobilization have shown that SB provided higher cell survivability of 93.6 % than that of 64.1% in PC. These result highlighted the greater role of solution holding capacity of cellulose in ensuring a better cell survivability after immobilization process. As conclusion, this study showed the near future potentiality of SB and PC as immobilization carriers for Lactobacillus rhamnosus NRRL 442. It may substitutes proportionally of raw materials and be functional feed for ruminant.