Food Irradiation: 55 MCQs with answers

High velocity electrons

X-rays are ionizing radiations produced by bombarding a suitable metal target with high velocity electrons, and they behave like Gamma rays.

100 rads

The Gray is a newer unit of radiation where 1 Gray = 100 rads = 1 joule/kg.

Potatoes, onion, garlic and mushrooms

Irradiation is permitted for inhibition of sprouting of potatoes, onion, garlic, mushrooms, etc.

True

1 Krad = 1000 rads, as stated in the radiation energy unit section.

To kill microorganisms and inhibit sprouting

The primary purpose of food irradiation is to kill microorganisms, parasites, and insects, or to inhibit sprouting and delay ripening.

Radappertization

Radappertization is used to destroy microorganisms and achieve commercial sterility of heat-processed foods.

REP

REP (Roentgen-Equivalent Physical) is defined as 1 REP = 83 ergs/g of matter.

Inhibition of sprouting in potatoes

Irradiation is permitted for the inhibition of sprouting in potatoes, among other uses.

2.5-10 kGy

Radicidation is classified with a radiation dose range of 2.5-10 kGy.

Cause rancidity

Free radicals can cause rancidity in high-fat products due to oxidative changes.

100 rads

1 Gray (Gy) is equivalent to 100 rads.

Gram-negative bacteria

Gram-negative bacteria are generally more sensitive to radiation than Gram-positive bacteria.

To minimize undesirable changes

Irradiating at low temperatures helps minimize undesirable changes such as discoloration and rancidity.

To kill microorganisms and delay ripening

The primary purpose of food irradiation is to kill microorganisms, parasites, and insects, or to inhibit sprouting and delay ripening.

Radappertization

Radappertization is the process used to destroy microorganisms and achieve commercial sterility of heat-processed foods.

2.5-10 kGy

Radicidation uses a dose range of 2.5-10 kGy to reduce non-spore-forming pathogens.

100 rads

1 Gray (Gy) is equivalent to 100 rads, as stated in the units of radiation dose.

Inhibition of sprouting in potatoes

Irradiation is permitted for the inhibition of sprouting in potatoes, among other uses.

83 ergs/g

1 REP (Roentgen-Equivalent Physical) is equivalent to 83 ergs/g of matter.

Gram-negative bacteria

Gram-negative bacteria are more sensitive to radiation compared to Gram-positive bacteria and spores.

Rancidity in high-fat products

Free radicals produced during irradiation can lead to rancidity in high-fat products.

To reduce spoilage organisms

Radurization is used to reduce spoilage organisms and extend the shelf life of food.

REP

1 REP (Roentgen-Equivalent Physical) equals absorption of 83 ergs/g of matter, whereas 1 RAD equals 100 ergs/g.

Radappertization

Radappertization destroys microorganisms and is equivalent to commercial sterility of heat processed foods, also called radiation sterilization.

30-40 KGy

Radappertization uses a radiation dose of 30-40 KGy to ensure a sterile product with prolonged shelf life.

Viable non-spore forming pathogens

Radicidation reduces the number of viable non-spore forming pathogens that are undetectable by standard methods, and is equivalent to pasteurization.

Radurization

Radurization substantially reduces viable specific spoilage microorganisms, enhancing keeping quality, and uses a dose of 0.75-2.5 KGy.

0.75-2.5 KGy

Radurization uses a radiation dose of 0.75-2.5 KGy, which is lower than that used in Radicidation and Radappertization.

Pectin and cellulose

Oxidative changes from free radicals can degrade pectin and cellulose, resulting in tissue softening in fruits.

Poultry, eggs, shrimps and frog legs

Irradiation is permitted for inactivation of Salmonella in poultry, eggs, shrimps and frog legs.

False

Radurization uses 0.75-2.5 KGy, which is much lower than the 30-40 KGy used in Radappertization.

Radappertization

Radappertization, with a dose range of 30-40 kGy, is specifically aimed at destroying microorganisms to achieve commercial sterility.

Radicidation uses a lower dose than Radurization

Radicidation (2.5-10 kGy) uses a higher dose than Radurization (0.75-2.5 kGy), making it more effective for reducing non-spore-forming pathogens.

To reduce undesirable changes caused by free radicals

Irradiating food at low temperatures helps minimize undesirable changes, such as discoloration and rancidity, caused by free radicals.

Gram-negative bacteria

Gram-negative bacteria are generally more sensitive to irradiation compared to Gram-positive bacteria and spores, making them least resistant.

Radicidation

Radicidation (2.5-10 kGy) is specifically designed to reduce non-spore-forming pathogens, making it equivalent to the pasteurization process.

They cause rancidity

Free radicals produced during irradiation can lead to rancidity in high-fat products due to the formation of carbonyl and peroxide radicals.

10^5 rads

1 kGy is equivalent to 10^5 rads, as defined in the units of radiation dose.

Inhibition of sprouting in potatoes

Irradiation is permitted for various uses, including the inhibition of sprouting in potatoes, which is a common application.

Direct interaction with key molecules

The microbicidal effect of irradiation primarily results from the direct interaction of radiation with key molecules within the microbial cell.

It aims for commercial sterility

Radappertization, with a dose of 30-40 kGy, is specifically designed to achieve commercial sterility of heat-processed foods.

Carbonyl and peroxide radicals

Carbonyl and peroxide radicals produced during radiation and subsequent storage in the presence of oxygen lead to rancidity in high fat products.

Irradiating at low temperature in absence of oxygen

Giving the radiation process at low temperature in the absence of oxygen reduces product discoloration and rancidity.

Gram negative bacteria

Gram negative bacteria are more sensitive to radiation than Gram positive bacteria, followed by spores which are most resistant.

Both direct interaction with key molecules and inhibitory effect of free radicals

Microbicidal effect results from direct interaction of radiation with key molecules within the microbial cell as well as inhibitory effect of free radicals (H+, OH- ions) produced by radiolysis of water.

30-40 kGy; Achieve commercial sterility

Radappertization uses a dose of 30-40 kGy to destroy microorganisms and achieve commercial sterility.

Radicidation is equivalent to pasteurization.

Radicidation is specifically designed to reduce non-spore-forming pathogens and is equivalent to pasteurization.

10^5 rads

1 kGy is equivalent to \(10^5\) rads, as 1 Gray equals 100 rads.

Radurization

Radurization is specifically aimed at reducing spoilage organisms and extending shelf life.

Rancidity

Irradiating in the absence of oxygen helps to minimize rancidity caused by free radicals in high-fat products.

Reduction of non-spore-forming pathogens

A dose of 5 kGy falls within the Radicidation range, which effectively reduces non-spore-forming pathogens.

E. coli is a poor indicator of sensitivity to irradiation.

E. coli is highly sensitive to irradiation and is not useful as an indicator of resistance.

Oxidative rancidity

Free radicals can lead to oxidative rancidity in high-fat products, negatively affecting food quality.

Radurization uses a lower dose than Radicidation.

Radurization uses a dose range of 0.75-2.5 kGy, which is lower than the 2.5-10 kGy used in Radicidation.

Delay in fruit maturation

Irradiation is permitted for delaying the maturation of fruits such as strawberries, mangoes, and papayas.