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LWT - Food Science and Technology xxx (2012) 1e6

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LWT - Food Science and Technology
journal homepage: www.elsevier.com/locate/lwt

Osmotic dehydration under high hydrostatic pressure: Effects on antioxidant
activity, total phenolics compounds, vitamin C and colour of strawberry
(Fragaria vesca)
Yissleen Nuñez-Mancilla a, MarioPérez-Won a, Elsa Uribe a, Antonio Vega-Gálvez a, b, Karina Di Scala c, d, *
a

Departament of Food Engineering, Universidad de La Serena, Av. Raúl Bitrán s/n, 599 La Serena, Chile
CEAZA, Center for Advanced Studies in Arid Zones, Universidad de La Serena, Av. Raúl Bitrán s/n, Box 599, La Serena, Chile
Food Engineering Research Group, Facultad de Ingeniería, Universidad Nacional de Mar del Plata, Av.Juan B. Justo 4302, Mar del Plata, Argentina
d
CONICET (Consejo Nacional de Investigaciones Científicas y Técnicas), Argentina
b
c

article info

abstract

Article history:
Received 12 August 2011
Received in revised form
22 February 2012
Accepted 24 February 2012

Simultaneous application of osmotic dehydration under high hydrostatic pressure conditions of strawberries was studiedwith the purpose of analyzing the effect of the combined process on the antioxidant
capacity, phenolic compounds, colour and vitamin C of strawberries during refrigerated storage. The
osmotic solution was prepared using commercial sugar at 40  Brix. Samples were pressurized between
100 and 500 MPa for 10 min. The radical scavenging activity showed higher antioxidant activity at
400 MPa ratherthan at low pressure (100, 200 and 300 MPa). The total phenolic content increased with
pressure presenting a maximum at 400 MPa. Pressurized samples retained vitamin C content. Based on
these results, working at 400 MPa for 10 min ensures physicochemical and high levels of nutritional
parameters in osmo-dried strawberries.
Ó 2012 Elsevier Ltd. All rights reserved.

Keywords:
Osmoticdehydration
High hydrostatic pressure
Antioxidant capacity
Total phenolic content
Colour
Vitamin C
Strawberry

1. Introduction
Strawberries (Fragaria vesca) which are very popular fruits
available during the spring and summer period are highly perishable and susceptible to bruises and fungal attacks (Blanda et al.,
2009). Strawberry quality for the market is focused on physical
qualities butthere is an increasing interest in the health benefits of
the fruit as a result of consumer’s demands that look for food
products that taste, smell and look attractive while providing
nutritional benefits (Shin, Ryu, Liu, Nock, & Watkins, 2008). Thus,
the handling of fresh products in the supply chain is an important
component for maintaining product quality and nutritional value
(Russell,LeBlanc, McRae & Ryan, 2009). Therefore, the food industry
is very interested in improving marketability of strawberries, not
only as fresh fruits but also as processed products. In this sense,
osmotic dehydration and high pressure processing are alternatives
* Corresponding author. Food Engineering Research Group, Facultad de Ingeniería,
Universidad Nacional de Mar del Plata, Av. Juan B. Justo4302, Mar del Plata,
Argentina. Tel.: þ54 2234816600.
E-mail address: kdiscala@fi.mdp.edu.ar (K. Di Scala).

to create new products with distinctive final characteristics. Application of high hydrostatic pressure (HHP) is an innovative, emerging
technology with potential for optimizing intake of nutrients in
human diets (McInerney, Seccafien, Stewart, & Bird, 2007; VegaGálvez et al., 2011).During osmotic dehydration, a cell placed in a hypertonic
solution (osmotic pressure higher than that of the cell) will lose
water. As the cell wall is permeable the volume between the cell
wall and plasmalemma fills with the hypertonic solution (Lewicki &
Lenart, 2006). Combination of high hydrostatic pressure with
osmotic dehydration leads to cell dehydration while gaining in
soluble...