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Tag : Quality

Biomarkers for onion storage

The aim of onion bulb storage is to meet consumer demand for extended availability of onions whilst maintaining product quality. The principal biological factors leading to onion bulb deterioration are respiration, resumption of growth and pathogen attack. In onion bulbs a dormant period, when sprouting and rooting can not be induced, is followed by a period of internal changes that prepare the bulb for breaking of dormancy and subsequent growth. Out of storage, the bulb then proceeds towards flowering and seed production. Sprouting occurs when the leaf primordia that are produced in stored onion bulbs develop green leaves, rather than scale leaves, which elongate and eventually protrude from the neck of the bulb. The growth rate of the sprout inside the bulb varies according to cultivar and storage regime, and is a major factor in determining the storage life of onions. Temperature has a profound effect on the dormancy period and storage life of onion bulbs. In general, sprouting is inhibited both by low and by high temperatures, and encouraged at intermediate temperatures. Cultivars respond differentially to temperature. Typically, the optimum temperature range for sprouting in dry storage is 10-20ºC. Moisture loss is greater at temperature ranges <10ºC and >27ºC.... Read more

How online nondestructive quality sorting can improve fruit quality

Is anyone truly satisfied with the taste of the fruits that we find in supermarkets today? Fruits that are destined to be stored for extended periods to regulate marketing, or to be shipped extended distances to reach far-flung markets, are too often harvested at an early stage of development that provides no chance that those fruit will ever develop excellent flavor and aroma.... Read more

Has apple storage really altered in 90 years?

Apples still represent one of the most important fresh produce types within the fresh fruit and vegetable category. Standard quality control for apple fruit is usually based on setting a numerical lower limit for firmness, soluble solids content, starch pattern index, colour and mass. All these factors affect quality but are commonly measured using rather rudimentary equipment which is known to have some flaws. This said, recent published research has shown that apple firmness is the most important factor in determining consumer acceptance of apples (Harker et al., 2008). Soluble solids content and acidity also play a role in defining consumer preference within specific cultivars. Mealiness is a negative attribute. There has been a positive trend towards consumers choosing to purchase firm/crisp apples, whilst a small proportion still value softer and more aromatic cultivars; these being inherently more challenging to store. However, is the consumer driving the selection of firmer varieties or is it availability (i.e. what they are presented with) and/or standardisation/consistency? Apple quality (the product) is only one aspect which governs consumer choice; price, promotion, place and packaging (the 5 P’s) are also important. In addition, availability is also key. This has been increased through cold storage, ethylene control/suppression and controlled atmosphere storage such that consumers are often faced with fruit from both hemispheres. Consumers thus have to choose (consciously or not) between short to long-term stored fruit (Varela et al., 2008). However, the notion that longer stored produce are less fresh and thus inferior does not always stand true. Time is only one factor which governs postharvest quality. The storage conditions, postharvest treatments and handling are the defining criteria which ultimately affect quality.... Read more