Fermentation of Cucumbers Without Sodium Chloride

Cucumbers were successfully fermented and stored in the absence of sodium chloride (salt) under laboratory conditions, provided the fruit were blanched (3 min, 77°C) before brining in a calcium acetate buffer and the brine inoculated with Lactobacillus planturum. Bloater formation was prevented by blanching even when brines were not purged of CO₂. Firmness of cucumbers was similar in salt-free brines or those containing salt after 1 mo, but firmness of salt-free cucumbers was lower after storage for 12 mos. Under pilot-scale, commercial conditions, however, the cucumbers were severely bloated, and the firmness was unacceptable after storage for 7 mo, due apparently to Microbial recontamination after blanching.     

Blanching Effects on the Chemical Composition and the Cellular Distribution of Pectins in Carrots

ABSTRACT: Carrots were blanched using 4 time-temperature combinations. Galacturonic acid and sugar contents of pectin extracts were determined, and immunocytochemistry experiments elucidated changes in the cell membrane. Blanching decreased galacturonic acid and total sugar contents for all treatments. Carrots subjected to high-temperature short-time (HTST) blanching contained more total galacturonic acid and total sugars in pectins than carrots blanched for a long time at low temperatures (LTLT). Similar trends were observed for methylated pectin and neutral sugars. Immunocytochemistries showed separation of the 3-way junction of cell walls, and LTLT-blanched carrots showed higher levels of JIM 7-labeled pectin (1.6 × 10⁻⁴ particles/nm²) than HTST-treated carrots (5.9 × 10⁻⁵ particles/nm²).     

烫漂对菠菜和苋菜中草酸和V_C的影响

研究了不同烫漂条件对菠菜和苋菜中草酸和VC的影响。结果表明,随加热时间的延长、漂烫温度和pH的提高,菠菜和苋菜中的草酸和VC的含量随之下降;酸性条件有利于VC的保护,但不利于草酸的溶出;食盐有利于VC的保护及草酸的溶出,食盐浓度提高,此效果越明显。     

预处理工艺条件对冻干白萝卜脆片品质的影响

目的? 考察护色、漂烫和磁场辅助冷冻对真空冷冻干燥白萝卜脆片品质的影响。方法 在单因素实验的基础上，以白度、营养成分保留率、硬度、韧性为评价指标，选取护色剂（抗坏血酸）质量浓度、漂烫时间、漂烫温度进行三因素三水平正交实验，确定白萝卜脆片品质最佳的漂烫条件。在此基础上，考察不同强度静磁场（0、0.4、0.8、1.2、1.6 mT）强度对白萝卜的冻结曲线以及冻干白萝卜脆片复水比的影响。结果? 抗坏血酸质量浓度10 g/L、漂烫时间3 min、漂烫温度60℃、静磁场强度0.8 mT辅助冷冻处理，可使真空冷冻干燥白萝卜脆片获得较好的品质。结论 真空冷冻干燥白萝卜脆片的加工过程中，采用适宜的护色、漂烫工艺以及磁场辅助冻结处理，可有效提高产品的品质。本研究可为果蔬脆片的加工以及白萝卜的精深加工和高值化利用提供参考。