Volume 5 • Issue 12 • 1000402
J Food Process Technol
ISSN: 2157-7110 JFPT, an open access journal
Open Access Research Article
El-Sharnouby et al,. J Food Process Technol 2014, 5:12
DOI: 10.4172/2157-7110.1000402
*Corresonding author: Gamal A. El-Sharnouby, Department of Food and Nutrition
Sciences, College of Agricultural and Food Sciences, King Faisal University, Saudi
Arabia, Tel: 0557786398; E-mail: Gelsharnoby@kfu.edu.sa
Received May 06, 2014; Accepted December 03, 2014; Published December
10, 2014
Citation: El-Sharnouby GA, Aleid SM, Al-Otaibi MM (2014) Liquid Sugar Extraction
from Date Palm (Phoenix dactylifera L.) Fruits. J Food Process Technol 5: 402.
doi:10.4172/2157-7110.1000402
Copyright: © 2014 El-Sharnouby GA, et al. This is an open-access article
distributed under the terms of the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided
the original author and source are credited.
Abstract
In date syrup manufacturing, date fruits (Phoenix dactylifera L.) are mixed with a suitable amount of water with heating at a
temperature greater than 70°C for about 1 h. These conditions are not satisfactory for extraction greater amount of liquid sugar
(date syrup). In addition, overheating for an extended period could damage nutritious materials and changes product’s color. In this
study, pectinase/cellulase enzymes and sonication processes were used to achieve maximum syrup extraction from a date variety
(Reziz) compared with classical method. The following variables were examined: fruit/water ratio, mixture of enzymes percent and
ultrasonic power. Enzymes and Ultrasound were applied for improving the quantity and quality of extracted syrup. Date extract was
fltered with flter system (Novox 200, fltrox) which could result entirely a clear syrup and then concentrated by a rotary evaporator
until about 75% total solids to produce higher quality syrup. Physicochemical properties of each collected sample during process
were evaluated. Results showed that sonication power 25% at ratio 1/3 D/W could lead to a higher extraction of RSS (Recovery of
Soluble Solids) (74.30%) in a shorter time with a better physicochemical quality of syrup in comparison to mixture of enzymes 1.0%
(66.70%) and classical methods of extraction (58.45%). Data indicated the possibility of employing ultrasound (25%) or enzymes
processes (pectinase/ cellulase 0.1%) for producing greater syrup amount highly desirable for use in food product development.
Liquid Sugar Extraction from Date Palm (Phoenix dactylifera L.) Fruits
Gamal A El-Sharnouby
1
*, Salah M Aleid
1,2
and Mutlag M Al-Otaibi
1
1
Department of Food and Nutrition Sciences, College of Agricultural and Food Sciences, King Faisal University, Saudi Arabia
2
Date Palm Research Center of Excellence, King Faisal University, Saudi Arabia
Keywords: Date syrup; Reziz; Enzymes; Ultrasound; Extraction;
Liquid sugar
Introduction
Te date palm (Phoenix dactylifera L.) is one of the oldest fruit
trees in the Arabian Peninsula and has played an important role in
day-to-day life of the people of this region for the last 7000 years [1].
Te production of date fruits in the Kingdom of Saudi Arabia reached
about 1.07 million tons (annually). Te global production of fruit from
the date palm tree was estimated at 7.75 million tons worth US $3.82
billion in 2010 [2]. Saudi Arabia is ranked as the second largest date
producer in the world afer Egypt, with an annual production of 1.078
million tons of dates produced from over 24 million date palm trees [3].
Te development of date fruits is divided into three stages, Khalal,
Rutab and Tamr. Khalal stage dates are immature with hard texture,
yellow or red or pink color, Total Soluble Solids (TSS) (A portion of
the total solids which are dissolved in the water and pass through a
flter prepared by depositing a layer of Kaolin paste into a standard
flter paper) of 30-45 brix, astringent and edible; Rutab stage dates
sofen at the tip of the fruit, RSS of 55-60 °brix, free from astringency
and edible; Tamr stage dates are fully ripped with RSS of 60–84 °Brix
and edible. Dates are generally harvested at Tamr stage that is afer the
development of TSS of 60–70 °Brix that are edible at this stage. Date
syrup is used in food preparations like sweets, snacks, confectionery,
bakery products and health foods. Mature date fruits are also processed
into products such as date bars, date syrup, etc. Dates are known to
be rich in carbohydrates (80%) but quite low in protein (2-3%). Date
fruits (Tamr) contained moisture ranged from 10 to 22%, total sugars
62 to 75%, protein 2.2 to 2.7%, fber 5 to 8%, fat 0.4 to 0.7%, ash 3.5 to
4.2%, total acidity 0.06 to 0.20%, ascorbic acid 30.0 to 50.0 mg %,on dry
weight basis. Date fruit as a nutritive product contains sugar substances
about (70.6-76.3%), proteins (1.9-3%), fat (0.2-2.8%), minerals (1.3%)
and vitamins [4]. Te fesh of a fully ripe date (Tamr), consist of two-
third sugars and one-quarter water, the rest being mainly cellulose,
pectin, ash, and vitamins. Te date is considered as a nutritious fruit as
research has indicated the clear contribution of dates to human health
when consumed with other food constituents. Dates contain sufcient
quantities of minerals and vitamins that help to prevent defciency
[5]. Dates also have an emerging role of importance as a substitute for
refned sugar. In food technology, date syrup as the main and general
by-product of date is used for foodstufs such as jams, marmalades,
concentrated beverages, chocolates, ice cream, confectioneries, honey,
etc [6-8]. As the Kabkab (Iranian Kabkab Dates) date has a high amount
of wastes, it can be used for the date syrup production with economical
advantageous [9]. Date syrup (dibs) is probably the most common
derived date product. It is produced as an incidental by-product when
bagged humid dates are heaped for several months, some syrups
extracted by the force of their own weight. In addition, it is produced
in the home and village by extraction and boiling down of juice, and on
a semi and full industrial scale. As the Reziz date has a high amount of
wastes, it can be used for the date syrup production with economical
advantageous. In date’s syrup industry the fruit are mixed with water
and heated for around 1 h at 70°C, when the main components, sugars,
are extracted. Tis method destroys some nutritive components and
darkens the product’s color.
Specifc enzymes and enzyme combinations are needed to optimize
the extraction of any particular fruit juice about yield and quality. Te
use of cellulases and pectinases has been an integral part of modern
fruit processing technology, involving treatment of fruit mashes as
they not only facilitate easy pressing and increase in juice recovery,
but also ensure the highest possible quality of products. For example,
pectinases can hydrolyze pectin and cause pectin-protein complexes
to focculate, so the resulting juice has a much lower amount of pectin
and a lower viscosity, which is advantageous for the fltration process.
Tese enzymes not only help in sofening the plant tissue but also lead
to the release of cell contents that may be recovered with high yield.
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ISSN: 2157-7110