Guava pulp fermentation and processing to a vitamin B12-enriched product

Guava (Psidium guajava) pulp was fermented with Lactobacillus plantarum WU-P19 to a product rich in microbially produced vitamin B12 and conjugated linoleic acid. Different initial sucrose levels were tested in the pulp in different fermentations. The 36-hr fermented material had a pH of 3.3-3.4, a lactic acid content of 7.6-8.2 g/L, and a viable L. plantarum count of 10(8.51)-10(8.56) cells/ml. The fermented pulp was used to make a novel food product, the guava gummy jelly. The guava gummy jelly formulation that was most accepted by a panel of tasters, comprised of 100 g (fresh weight) of fermented guava pulp, 20 g of sucrose, 11 g of glucose syrup, 6 g of gelatin and 0.5 g of citric acid. A 1-g portion of this tasty product could fully meet the daily requirements of vitamin B12, an essential nutrient that is deficient in many diets. Practical applications Vitamin B12 deficiency in certain diets can be alleviated through consumption of the fermented food product produced here. The fermented product offers a high-value application of waste pulp of commercial guava juice production.