Study on nanocellulose isolated from waste chilli stems processing as dietary fiber in biscuits

Abstract

In order to expand the high added value of waste chilli stems and the recycling of green resources, cellulose in chilli stems was extracted by nitric acid–ethanol method, and nanocellulose was prepared by sulfuric acid hydrolysis method. The results showed that the cellulose content was between 15% and 34.5%. Under the optimum experimental conditions of 60% sulfuric acid concentration, 60°C reaction temperature and 120 min reaction time, the average yield of nanocellulose was 36.42% ±1.36%. Prepared cellulose and nanocellulose had been characterized using scanning electron microscopy, fourier-transform infrared, and x-ray diffraction analysis. The research indicated that the biscuits with acceptable overall quality could be prepared by using the dosage of nanocellulose (7%), and the corresponding biscuits had regular appearance and relatively smooth surface. The total dietary fiber content was positively correlated with different nanocellulose content. Through mice experiments, it was found that the consumption of biscuits containing nanocellulose could significantly reduce the food intake of mice and inhibit the weight growth of mice. Therefore, the research showed that whole wheat biscuits with nanocellulose could be regarded as food rich in dietary fiber. These results provided a basis for exploring the green resource recycling of chilli stems in food processing.