course hero what is controlled atmosphere storage?

Controlled atmosphere storage (CA) refers to the constant monitoring and adjustment of the CO2 and O 2 levels within gas-tight stores or containers. CA is most effective when combined with temperature control.

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What is controlled atmosphere storage?

Controlled-atmosphere storage (CAS) is one of the most important innovations in fruit and vegetable storage systems as the composition of gas in the storage affects their storage life. The CAS technology involves reduction of oxygen (O 2) and increasing carbon dioxide (CO 2) as compared to the ambient atmosphere. Sometimes it also involves removal of ethylene and …

How long has controlled atmosphere storage been used for fruit?

Controlled atmosphere storage is a system in which fresh, perishable products (such as fruit and vegetables) are stored under environmental conditions that extend the shelf life after harvest. In the past 50 years, controlled atmosphere storage has become a staple of the world-wide fruit industry and makes it possible for fresh, high quality fruit to be available year-round.

What is modified atmosphere storage?

The factors that provide a controlled atmosphere in the interview room is creating a space with little to no distractions. Eliminating any possible distractions allows the interviewee to stay on track and focus on the current situation. The interviewer must be able to control the room and show they have the upper hand at all times no matter the circumstances.

What is the composition of the atmosphere in a CA storage facility?

6 storage of fruit and vegetables in controlled. School Far Eastern University; Course Title EDUCATION 112; Uploaded By Anony92. Pages 14 This preview shows page 9 - 11 out of 14 pages. Students who viewed this also studied. Institute of …

Benefits of controlled atmosphere

It is the ideal long-distance transport for fruits and vegetables as it involves:

The role of ethylene

Ethylene plays a very important role in the controlled atmosphere chain. It is a determining organic compound in the ripening process of fresh fruits and vegetables. Its correct administration is key to preserving the characteristics of the food and its value in the market, especially in transport whose transit time exceeds 20 days.

What is controlled atmosphere storage?

Controlled atmosphere (CA) and modified atmosphere (MA) storage are technologies for extending the shelf life of foods, especially fruits and vegetables; and for eliminating pests in stored grains and oilseeds. The most important application of CA and MA is for long-term storage of apples, but the shelf life of certain other fruits (pears, sweet cherries) and vegetables (cabbage) can also be extended by these methods. In addition, there is considerable evidence that MA can extend the shelf life of meat, fish, poultry, fresh pasta, sandwiches, eggs, and bakery products. Because grains and oilseeds are more stable than high moisture foods (e.g., fruits, vegetables, meats), CA and MA are used primarily for disinfestation rather than for increasing the shelf life

How is controlled atmosphere storage different from airtight storage?

Controlled atmosphere storage is different from an airtight storage where gas ratios change naturally, although both are carried out in more or less gas-tight storage structures. In air-tight storage, the depletion of O2 and the accumulation of CO2 occur due to the metabolic processes of the insects, microflora, and the stored grain. Because the effectiveness of the air-tight storage is largely dependent upon the build-up of an infestation in the grain, it is not considered a satisfactory method. Controlled atmospheres are attained by introducing CO2 or N2 from external sources, possibly prior to the build-up of infestation, thereby preventing damage to the stored grain.

What are the benefits of CA and MA?

The improvements in quality arise from the general reduction in the rates of metabolic processes, retardation of physiological aging, enzymatic spoilage, and reduction in microbial growth. In fresh fruits and vegetables stored under optimal CA or MA, practical quality advantages include:

How long can grain be stored?

Grain can be stored for relatively long periods without a loss in viability, with a decreasing scale for longevity in oats, rice, barley, wheat, triticale, rye, sorghum and corn. The main factors that affect longevity are moisture and temperature with each 1% increase in seed moisture content (MC) halving the life of seed. This rule applies when seed moisture content is between 5 and 14%. Below 5% MC the speed of aging may increase because of auto-oxidation of seed lipids and above 14% MC storage fungi kill the seed. Also, for each 5°C increase in seed temperature, the life of seed is halved (from 0 to 50°C). The presence of O2 decreases seed germination, even at low partial pressures in dry grain because of membrane damage caused by the production of free radicals and accumulating chromosome damage.

What are the advantages of CA?

The main advantage of CA to disinfest grain is its potential to replace pesticides used in the grain industry. The CA-treated grain does not have any chemical residues which can cause considerable health concerns. In addition to providing an effective control of pests, CA storage prevents mold growth, preserves grain quality, and maintains a high level of germination in the stored grain. However, as with any other method of pest control, CA storage has limitations. The major limitation appears to be the high initial cost of air-tight storage structures, and the cost of sealing existing structures to the desired air-tightness. There is also the cost of the generation and transportation of the gas. The interaction of CA gases with the storage structure can cause some practical problems. The introduction of CO2 or N2 into airtight structures has the potential to increase the internal pressure on bin walls, and steps need to be taken to permit pressure equilibration. The only chemical reaction observed with CA involves CO2 in concrete silos. Carbon dioxide is bound by concrete through carbonation, which can result in reduced pressures developing in well-sealed new concrete bins. Also, carbonation of concrete can gradually extend to a depth where reinforcing steel is exposed and the steel may eventually corrode and weaken the storage structure.