Proposal for technological adaptation of small-sized green olives to Spanish-STYLE processing

Abstract

In this study, small-sized green olives were assessed for processing as Spanish-style table olives. Technological adaptations included the selection of three lye treatments, combined with a 3 h washing, a subsequent fermentation for 105 days in brine (12% NaCl (w/v) acidified with hydrochloric acid, 2.3 mL/L of brine) using a starter culture (OleicaStarter®) and preservation for 7 months in the fermentation brine fortified with NaCl up to 9%. Different physicochemical (pH, titratable, combined acidity, sodium chloride, sugars, fermentable matter, colour and firmness of fruits), and microbiological (yeasts, lactic acid bacteria and Enterobacteriaceae) and parameters were monitored during processing of the olives. The results showed that lye treatment with 3.4% sodium hydroxide was the most suitable treatment since it presented the highest values of titratable acidity. At the end of fermentation, all treatments presented physicochemical and microbiological parameters compatible with the production of Spanish-style table olives. Likewise, high levels of lactic acid bacteria present on the fruit epidermis could make these olives suitable as carriers of functional bacteria after ingestion (6.8–6.9 log CFU/g). Finally, preservation can maintain the stability and quality of table olives. All the results highlight that small-sized green olives can be successfully processed as Spanish-style table olives.