High‐pressure processing of shalgam with respect to quality characteristics, microbial inactivation, and shelflife extension

Abstract

High hydrostatic pressure (HHP) processing of traditional fermented turnip juice (shalgam) was studied with respect to quality attributes, microbial inactivation, and shelflife extension. According to Box–Behnken design, shalgam samples were processed using 3–15 min, 4–40°C, and 200–500 MPa. The optimum processing conditions involved 34.23°C, 15 min, and 500 MPa for the color intensity and tone of 3.43 and 0.69 and the numbers of viable total mold and yeast, Lactococcus lactis subsp. cremoris, and Lactobacillus paracasei of 3.09, 2.51, and 2.68 log cfu/ml, respectively. Shalgam samples processed under the optimum conditions were stored at 4 and 22°C for 90 days. The control samples at 4 and 22°C were spoiled at 60 and 45th days, respectively. The storage time rather than the HHP processing affected physical properties, organic acids, phenolic compounds, and anthocyanins of shalgam. The treatment samples had significantly lower microbial growth during the storage time. Practical applications Due to the deteriorated color, bioactive, and sensory properties, the traditional heat processing of shalgam with the addition of antimicrobial agents (such as sodium benzoate) to extend its shelflife is not desirable by consumers. Alternative processing technologies are needed to extend its shelflife with no significant changes in its important properties. Its HHP treatment appeared as a practical option that preserved its quality parameters and extended its shelflife.