Assessment of lettuce quality during storage at low relative humidity using Global Stability Index methodology

Abstract

<jats:p>During postharvest, lettuce is usually exposed to adverse conditions (e.g. low relative humidity) that reduce the vegetable quality. In order to evaluate its shelf life, a great number of quality attributes must be analyzed, which requires careful experimental design, and it is time consuming. In this study, the modified Global Stability Index method was applied to estimate the quality of butter lettuce at low relative humidity during storage discriminating three lettuce zones (internal, middle, and external). The results indicated that the most relevant attributes were: the external zone - relative water content, water content , ascorbic acid, and total mesophilic counts; middle zone - relative water content, water content, total chlorophyll, and ascorbic acid; internal zone - relative water content, bound water, water content, and total mesophilic counts. A mathematical model that takes into account the Global Stability Index and overall visual quality for each lettuce zone was proposed. Moreover, the Weibull distribution was applied to estimate the maximum vegetable storage time which was 5, 4, and 3 days for the internal, middle, and external zone, respectively. When analyzing the effect of storage time for each lettuce zone, all the indices evaluated in the external zone of lettuce presented significant differences (p &lt; 0.05). For both, internal and middle zones, the attributes presented significant differences (p &lt; 0.05), except for water content and total chlorophyll.</jats:p>

Impact of transportation, storage, and retail shelf conditions on lettuce quality and phytonutrients losses in the supply chain

“…The major reason for wilting was water loss due to transpiration through the stomata when the concentration gradient of the water vapor between the air spaces in the leaf and the surrounding environment was steeper (lower RH) (Ben‐Yehoshua & Rodov, ). Furthermore, fluctuation of temperatures (high) or RH (low) was shown to affect the quality of leafy vegetables (Ansorena et al., ; Munhuweyi, Linus Opara, & Sigge, ). Water loss results in cell wall degradation and affects the texture, turbidity and visual appearance (Ansorena et al., ; Piagentini, Güemes, & Pirovani, ), loss of vigor, and wilting (de Oliveira, Leal, Honório, & Soare, ).…”

“…Consumption of leafy vegetables such as lettuce is very popular nowadays not only due to their freshness but also for nutritive value and health benefits (Ansorena et al., ). Crisphead lettuce which is also known as Iceberg lettuce ( Lactuca sativa L.) is considered to be one of the furthermost popular, economically important and commonly consumed vegetables.…”

Effect of abiotic elicitation on the quality and antioxidant potential of lettuce and endive during storage

“…The panel for sensory analysis was composed of 20 members, aged from 21 to 40 years (12 women, 8 men). The leaf characteristics, such as color, texture, presence or absence of defects, and overall acceptability were evaluated on a scale of 1 to 5 (1—bad, 5—good) (Ansorena et al, ).…”

Plant Age Affects Wound-Induced Senescence in Lactuca Sativa L

“…We modified the OVQ scores proposed by Kader et al [27] to better suit our purpose by making the quality descriptions more explicit as follows: 9 = excellent, essentially free from defects 8 = very good, with minor changes in colour, and/or hardly visible browning 7 = good, with minor changes in colour and structure or slightly visible browning 6 = fair, with minor changes in colour and structure and slightly visible browning 5 = fair, clear changes in colour and structure and clearly visible browning, below the limit of sales appeal 3 = poor, with excessive changes in colour and structure, and very pronounced browning 1 = extremely poor, not usable Although subjective in nature, the OVQ ratio is a good means to compare quality deterioration between different treatments. The OVQ rating integrates different types of quality defects that may occur in parallel during leaf ageing [28,29] and OVQ was found to correlate well with quality measured by a combination of instrumental measurements [30]. An OVQ rating of 6 was considered the lower limit of consumer acceptance.…”