Page 35 - FoodFocusThailand No.154 January 2019

SMART PRODUCTION

Such phenomenon is known as double bond carbon atoms in proteins or nucleic acids in microorganisms absorb the
“Electroporation” or “Poreformation” where projected light energy, thus inducing cellular metabolism interferences. Additionally, when
transient pores are formed in cell membranes, light energy is released onto the food, rapid transfer and transformation of energy takes
some of which then become selectively- place on the food surface – a process which significantly increases the surface temperature
permeable membranes that are more and consequently destroys the cells of microorganisms such as E. coli and L.
conducive to transitory movement of monocytogenes (Ozer and Demirci, 2006). Apart from microbial elimination, pulsed light
substances. This phenomenon can be can inhibit enzymatic browning in potatoes as well.
sub-classified into 2 following types:
• Irreversible Electroporation เอกสารอ้างอิง/Reference
The cell burst is caused by the induction นิพัฒน์ ลิ้มสงวน. 2554. เทคโนโลยีใหม่ในการแปรรูปและถนอมอาหาร ตอนที่ 1. วารสารอาหาร ปีที่ 41 ฉบับที่ 3
of high-intensity electric field that considerably กรกฎาคม-กันยายน.
exceeds the critical threshold (E>>Ec) and Nipat Limsangouan. 2011. Neo Technology in Food Processing & Preservation Phases 1. Food Journal,
consequently causes irreversible damage to Vol.41 No.3 July-September.
the targeted cell membranes. The acquired
large-sized pores prevent the membranes
from assuming their original functions. Such
technique is applied to food preservation to
inhibit microbial growth.
• Reversible Electroporation
This cell burst is caused by the induction
of high-intensity electric field that slightly
exceeds the critical threshold (E.Ec). Small-
sized pores that can enhance mass transfer
through cell membranes are created as a
result. This technique causes zero to minor
damage to the cell membranes (Pimjai, 2009),
thus allowing them to retain their original
functions.
Currently, there are many studies on the
applications of PEF in the food industry such
as microbial inactivation in food products (Ho
and Mittal, 2000; Cserhalmi et al., 2002),
development of substance extraction from
natural ingredients (Fincan et al., 2004),
enhancement of dehydration efficiency (Taiwo
et al., 2002), and modification of enzymatic
properties (Yoem et al., 2000).

Pulsed Light
Pulsed light is a rapid, intense, and magnified
flash of light or electrical energy. Pulsed light
is applicable in inhibiting microorganisms, for
example, UV light projected onto drinking
water or UV light bulbs used to inhibit fungal
growth on bakery products as well as to
eliminate airborne microbial agents. In
addition, pulsed white light, with wavelength
similar to that of sunray, is put into use as well.
This new technology was first applied to food
products by an American company. It is
applicable in inhibiting microorganisms on the
surfaces of foods and packaging materials as
well as to sterile food. Pulsed white light has
a relatively broad spectrum, which is between
UV light wavelength (200 nm) and that of
infrared (100 nm). Unlike irradiation,
pulsed light does not ionize substances.
However, it can inhibit microbial growth on
food surface. The inhibition takes place when

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