Orange peel fermentation using Lactiplantibacillus plantarum: microbiological analysis and physico‐chemical characterisation

Abstract

To find an innovative use for orange peels discarded in the orange juice-making process, a fermentative process was assessed using a Lactiplantibacillus plantarum strain. Blanched or rinsed peels were submerged in a 5% NaCl-3% inoculated sucrose brine for 10 days. Total soluble solids, pH, sugars and total aerobic and anaerobic counts were determined in the brines to characterise the process. The final products were characterised by instrumental texture, colour and volatile composition. The blanching pretreatment had a significant effect on the whole process and the final product characteristics. Anaerobic bacteria total counts were significantly higher in the blanched samples during the whole fermentation, and pH decreased significantly slower in these samples than in the rinsed ones. Rinsed samples were characterised by higher aerobic total counts, higher sucrose consumption and higher glucose, fructose and polyalcohols production. The texture was softer in the pretreated samples, probably due to the blanching process rather than the fermentation. The volatile composition was quite similar between samples, although it was different from one of the raw orange peels due to a significant decrease in various volatile compounds.

Assessment of different debittering techniques to valorize orange peel

“…Measurement conditions were the previously reported by Deba‐Rementeria et al . (2022). Peak cutting force was considered as the first peak force in g; a total of 15 replications were carried out for each sample.…”

“…OPs were immersed for 10 min in boiling water (≈175 g in 1 L of water) and rinsed. Then, the blanched samples were introduced into previously sterilised 500 mL glass jars (Bormioli Rocco, Italy) filled with sterile tap water and inoculated with Lactiplantibacillus plantarum (Harvest LB‐1 culture L. plantarum pure culture lyophilized; CHR Hansen, Denmark) as suggested in previous research (Bousmaha et al ., 2006; Deba‐Rementeria et al ., 2022). Filled jars were closed with plastic lids with an airlock (Sterikap®, UK) and placed in a dark room with controlled temperature (21 ± 2 °C) for 10 days. Alkaline blanching using 1% Na 2 CO 3 (ALK sample).…”

“…The volatile composition of the samples was determined using headspace solid phase micro‐extraction (HS‐SPME) using the same conditions as previously reported (Deba‐Rementeria et al., 2022). A total of 0.3 g of milled sample was weighted, and ultrapure water (10 mL) and NaCl (1.0 g) were added into a 40 mL vial with polypropylene caps and PTFE/silicone septa.…”

“…Hardness of the samples was determined using a Texture Analyser Aname (Microstable system, UK) using an HDP/BSK blade set probe (Warner-Bratzler with rectangular slot blade). Measurement conditions were the previously reported by Deba-Rementeria et al (2022). Peak cutting force was considered as the first peak force in g; a total of 15 replications were carried out for each sample.…”

Physicochemical and Sensory Evaluation Data to Drive the Development of a Green Chili Pepper Hot Sauce from Unexploited Raw Materials

“…The volatile compositions of the samples were determined by headspace solid phase micro-extraction (HS-SPME) using the same conditions, fiber, column, and equipment reported by Deba-Rementeria et al [31]. A total of 0.5 g of freeze-dried sample was weighted and ultrapure water (10 mL) and NaCl (1.0 g) were added into the 40 mL vial with polypropylene caps and PTFE/silicone septa for the extraction and processing as reported by these authors.…”