Heat Conditioning of Cucumbers Improves Retention of Sliced Refrigerated Pickle Texture and Appearance

Abstract

The effects of heat conditioning (HC) pickling cucumbers in 50C water on sliced refrigerated pickle product texture, white appearance, pectic substances and proteins during storage were examined. Conditioning for 45 and 60 min effectively hindered softening and cure appearance development (CAD) during 12 months of storage. Maintenance of firmness and white appearance of sliced pickles was achieved when cucumbers were processed within 1 h after HC and when processing was delayed for 24 and 48 h after HC. Conditioning cucumbers for 60 min prevented changes in the solubility of pectic substances and proteins in the pickled product mesocarp tissue during storage, while major changes occurred in mesocarp of the control treatment. SDS-PAGE demonstrated the production of low molecular mass proteins in response to HC, and that it enhanced retention of distinct proteins in the refrigerated pickle mesocarp tissue. Retention of pickle product texture and white appearance induced by HC appeared to be associated with stabilization of pectic substances and proteins. PRACTICAL APPLICATIONSHC of cucumbers before processing has potential to substantially enhance retention of texture and white appearance of sliced refrigerated pickles during storage and marketing.

Effects of a brief blanching process on quality, safety, and shelf life of refrigerated cucumber pickles

“…Buescher et al. (2013) found that heat conditioning whole cucumbers for 45 min aided in maintaining a minimally cured appearance (<20% CAD over a 12‐month shelf life) by production of small peptides and stabilization of the cucumber cell wall polysaccharides and proteins during refrigerated storage. During the heat conditioning in Buescher's study, mesocarp and endocarp tissue reached ∼48–49°C.…”

“…The subgroups were randomly assigned to the following four treatments, in duplicate: no blanch (control), blanch at 80°C for 15, 90, or 180 s, respectively. Cover brine was formulated based on typical commercial refrigerated pickle composition (Buescher et al., 2013; Lu et al., 2013) such that cucumber pickles equilibrated to 74 mM (0.44% wt/vol) acetic acid, 376 mM (2.2% wt/vol) sodium chloride, 6.9 mM (0.1% wt/vol) sodium benzoate to inhibit yeasts and molds and prevent fermentation, and 11.0 mM (0.12% wt/vol) calcium chloride with an equilibrated pH ∼3.8.…”

“…Consumers associate loss of opaqueness with loss of texture or freshness, important determinants of shelf life in refrigerated pickles (Fellers & Pflug, 1967). Interestingly, mild thermal treatment of cucumbers prior to pickling preserves the mesocarp opacity and crisp texture of refrigerated pickles (Buescher et al., 2013). Similarly, hot water dip treatments preserve the texture of raw produce such as strawberries, broccoli, and potatoes (Lurie, 2006).…”

Processing of Non-Fermented Sour-Sweet-Slices of Cucumbers (Cucumis Sativum L)

“…The lag period was not observed when a pre-oxidized solution of ascorbic acid was used, suggesting that a product of ascorbic acid oxidation is responsible for the onset of browning [13].Ascorbic acid was a very efficient antioxidant against formation of hexanal, (E)-2-penenal, (E)-2-hexenal, (E)-2-heptenal, and (E)-2octenal when slurries of fermented cucumber tissue were exposed to oxygen and most of these oxidative was efficiently prevented at 1755 ppm [14].Non-chemical browning of cucumber includes interactions of amino acids and sugars at various levels of pH that could affect the colour of cucumber by non-enzymatic browning through several kinetic reactions that would reduce the contents of amino acids and sugars [11,20]. Model experiments showed that the level of 5-hydroxymethylfurfural (5hmf) at pH 3.5 from fructose was 31.2 times faster than glucose, whereas sucrose was 18.5 times faster than glucose [21]. The contents of citric acid, calcium, magnesium, potassium, and the amino acids alanine, aspartic acid, and γ-aminobutyric acid could accelerate formation of 5hydroxylfumerate.Model systems were employed to determine the relative reactivity of sucrose, glucose, and fructose in the formation of 5-hydroxymethylfurfural (5-hmp) at pH 3.5.…”

Physical properties of NaCl-free cucumber fermentation cover brine containing CaCl2and glycerin and apparent freezing injury of the brined fruits

“…Previous studies have proposed time-temperature profiles for the use of hot-air (Mao, Wang, Zhu, & Pang, 2007) and hot-water treatments to reduce chilling injury and preserve texture of whole fresh cucumbers (McCollum, McCollum, Doostdar, Mayer, and McDonald, 1995) and sliced pickles (Buescher, Cho, & Hamilton, 2013). Chilling injury is defined as a physiological alteration that negatively affects the quality of fruits and vegetables causing pitting, surface discoloration, water soaking, internal breakdown, susceptibility to fungal attack, loss of cell membrane semipermeability, decay, and increase in electrolyte leakage at temperatures above the freezing point (Aghdam & Bodbodak, 2014).…”