Effect of sulfites and sorbates on the preservation and color of pickled blanched garlic under different storage conditions

Abstract

The influence of sulfites and sorbates on the microbial stability and color of pickled blanched garlic stored under different conditions was studied. Two storage temperatures (ambient, 20-24C; refrigeration, 6-9C) and two types of packaging (glass bottle, plastic pouch consisting of polyester/polyethylene/saran) were considered. Both sulfites and sorbates gave satisfactory results as antimicrobial agents, even at room temperature. Sulfite was also effective as an anti-browning agent, but sorbate produced the opposite effect on color. The samples packed in plastic pouches stored at room temperature had the highest values of the parameters b* (yellowness), C (color purity) and browning index. The sorbate level hardly changed during storage, regardless of the storage conditions used, but the sulfite level decreased, especially in samples packed in plastic pouches stored at room temperature, in which oxidation to sulfate was demonstrated to be the sole mechanism of sulfite loss. Practical Applications: Long-term preservation of pickled blanched garlic without the need for expensive preservation treatments such as pasteurization or refrigeration is possible with the help of sulfites and/or sorbates as preservatives. However, these preservatives yield opposite effects on garlic color. The data collected in this study demonstrated that sulfite at approximately 100mg/L of SO2 at equilibrium was an effective antimicrobial and anti-browning agent. For practical purposes, we recommend the use of sulfites alone and glass packages to maintain the quality of pickled blanched garlic as the presence of sorbates and/or the use of plastic packages enhance browning reaction. © 2014 Wiley Periodicals, Inc.