Cooperative effects of slight acidic electrolyzed water combined with calcium sources on tissue calcium content, quality attributes, and bioactive compounds of 'Jiancui' jujube

Abstract

BACKGROUND: Slight acidic electrolyzed water (SAEW) has been widely used in cleaning systems of fruit and vegetables. It strongly reduces microbial contamination. However, no information is available on whether SAEW offers the potential for fresh jujube cleaning. The purposes of this study were, first, to compare the effectiveness of SAEW with commercial sanitizers (i.e. sodium hypochlorite (NaClO) or calcium hypochlorite (Ca(ClO) 2 )) on 'Jiancui' jujube; second, to determine the response of fruit decay, tissue calcium (Ca) content, and quality attributes to dip application of calcium nitrate (Ca(NO 3 ) 2 ) by concentration; and third, to investigate the effects of SAEW combined with Ca(NO 3 ) 2 or calcium acetate (Ca(OAc) 2 )) on fruit Ca uptake, quality attributes, and bioactive compounds.RESULTS: Fruits washed with NaClO, Ca(ClO) 2 , or an SAEW solution showed no difference in reduction of decay incidence. In contrast to NaClO treatment, SAEW or Ca(ClO) 2 significantly retarded losses in fruit firmness (FF), green color (hue angle), and skin lightness (L*), and maintained intact pericarp tissue structure during storage at 1 ∘ C. Application of Ca(NO 3 ) 2 at 5-10 g L −1 effectively promoted Ca 2+ uptake and minimized declines in FF and L* value but had no effect on decay development. Adding 10 g L −1 Ca(NO 3 ) 2 or Ca(OAc) 2 to SAEW provided an additional benefit in increasing decay resistance, increasing Ca 2+ into fruit and increasing levels of bioactive compounds in jujube fruit. CONCLUSION: SAEW in combination with Ca(NO 3 ) 2 or Ca(OAc) 2 has commercial potential for fresh jujube disinfection and improving storage quality as a result of the cleaning processes.

Impacts of alkaline‐electrolyzed water treatment on physicochemical, phytochemical, antioxidant properties and natural microbial load on ‘Granny Smith’ apples during storage

“…TPC of apples increased from 709 ± 174.7 mg GAE L −1 fresh weight on day 0 to range from 1030 to 1412 mg GAE L −1 on day 21. This result agrees with other studies (Li et al ., 2020b). Relative influence of AEW > NaOCl = control on TPC.…”

“…Total flavanol content of apples increased significantly throughout storage, that is, from 119 to 251 mg CE L −1 at the end of storage. These results are consistent with other reports using AEW treatment on fresh produce (Chen et al ., 2020; Li et al ., 2020b). Maintaining relatively high total flavonoid in fruit during storage might contribute to reducing decay development and enhanced resistance (Zhi et al ., 2017).…”

“…2a), compared to other treated apples. Similarly, other studies have demonstrated that EW treatments maintained antioxidant capacity compared to control samples (Li et al ., 2020a, 2020b). Overall, AEW treatment maintained a relatively high TEAC levels in ‘Granny Smith’ apples.…”

Influence of the type of calcium salt on the cation absorption and firmness of black ripe olives

“…However, calcium absorption in fruit and vegetables depends on many factors, including the fact that the type of salt is relevant (Silveira et al, 2011;Li et al, 2020).…”

“…With this in mind, there have been some studies on partial NaCl substitution in Spanish‐style green olives with other salts such as CaCl 2 (Rodríguez‐Gómez et al ., 2012). However, calcium absorption in fruit and vegetables depends on many factors, including the fact that the type of salt is relevant (Silveira et al ., 2011; Li et al ., 2020). Indeed, a direct relationship between calcium uptake and firmness or uronic acid content has not been observed in many studies, which suggests a cross‐link of the cation with cell wall polysaccharides other than pectins (Manganaris et al ., 2005).…”