Commercial Scale Cucumber Fermentations Brined with Calcium Chloride Instead of Sodium Chloride

Abstract

Development of low salt cucumber fermentation processes present opportunities to reduce the amount of sodium chloride (NaCl) that reaches fresh water streams from industrial activities. The objective of this research was to translate cucumber fermentation brined with calcium chloride (CaCl2 ) instead of NaCl to commercial scale production. Although CaCl2 brined cucumber fermentations were stable in laboratory experiments, commercial scale trials using 6440 L open-top tanks rapidly underwent secondary cucumber fermentation. It was understood that a limited air purging routine, use of a starter culture and addition of preservatives to the cover brine aids in achieving the desired complete cucumber fermentation. The modified process was used for subsequent commercial trials using 12490 and 28400 L open-top tanks packed with variable size cucumbers and from multiple lots, and cover brines containing CaCl2 and potassium sorbate to equilibrated concentrations of 100 and 6 mM, respectively. Lactobacillus plantarum LA0045 was inoculated to 10(6) CFU/mL, and air purging was applied for two 2-3 h periods per day for the first 10 d of fermentation and one 2-3 h period per day between days 11 and 14. All fermentations were completed, as evidenced by the full conversion of sugars to lactic acid, decrease in pH to 3.0, and presented microbiological stability for a minimum of 21 d. This CaCl2 process may be used to produce fermented cucumbers intended to be stored short term in a manner that reduces pollution and waste removal costs.

Quality of Cucumbers Commercially Fermented in Calcium Chloride Brine without Sodium Salts

“…Higher pasteurization temperatures and longer processes have been previously correlated with softer finished product [36]. Despite the overall reduction in mesocarp firmness in the finished products, the cucumber pickles fermented in NaCl brine were still significantly firmer than those fermented with the CaCl 2 process by 1.6 N. Instrumental mesocarp firmness values are well correlated with sensorial measurements of firmness, crispness, hardness, and crunchiness [3,19,20,37,38]. Wilson et al [15] found significant differences in hedonic texture liking for hamburger dill chips produced from cucumbers preserved by NaCl and CaCl 2 fermentation processes that were 1.1 N different in instrumental firmness values.…”

“…In the laboratory development of the process, mesocarp firmness of cucumbers fermented in this CaCl 2 brine was found to be consistently comparable to the cucumbers fermented in a commercial brine formulation [4]. In contrast, cucumbers fermented in 12,500 L open-top tanks with the postcommercialization formulation changes showed variability in mesocarp firmness values as well as lower sensory hardness, fracturability, crispness, and crunchiness scores in some pickle products fermented and stored in CaCl 2 brines [3]. Consumer testing also showed a decreased texture liking for cucumber pickles commercially produced with the CaCl 2 brining process in some, but not all, experiments [15].…”

“…Despite extensive reuse of spent brines, processors still routinely produce high volumes of salty wastewater from the desalting process. Pérez-Díaz et al [3] estimated that the production of fermented cucumber pickles in the United States resulted in 45 million liters of wastewater containing 0.58 M NaCl from desalting processes, 1.3 billion liters of wastewater with 79 mM chlorides, and 12,000 tons of salt sludge solid waste.…”

“…Since the development of this process, attempts to commercialize the technology have resulted in slight adjustments of the brine formulation and process. These adjustments included the elimination of acetic acid from the brine formulation, addition of 6 mM potassium sorbate, and introduction of a minimal air-purging routine [3]. A typical purging routine utilizes the flow of air or nitrogen gas through the brine during the active fermentation period to help encourage the removal of carbon dioxide [5][6][7].…”

“…During the early stages of commercialization, fermentations using the alternative CaCl 2 process were found to spoil much more easily than in the current commercial process. Therefore, the air-purging routine was altered to minimize the introduction of oxygen and potassium sorbate was added as a preservative against yeast spoilage [3]. Acetic acid can serve as a substrate for oxidative spoilage yeasts such as Issatchenkia occidentalis and Pichia manshurica [14], so it was removed from the brine formulation as well [3].…”