Transcript Avocado Oil talk

Recent Research on the
Health Components in
Cold Pressed Avocado Oil
Marie Wong Massey University
Cecilia Requejo HortResearch
Tony McGhie HortResearch
Yan Wang Massey University
Laurence Eyres NZIC Oil & Fats Group
Allan Woolf HortResearch
Refined Avocado Oil
 Avocado oil is not new
 Used for cosmetics mainly
 Extracted - high temperature and/or solvent
 RBD (refined, bleached and deodorised)
 Gold colour, stable, little flavour
 High oleic acid
 High Vitamin E (α–Tocopherol)
Cold Pressed Avocado Oil
 Initially produced in NZ
 No significant processing
 Centrifuge at low temperatures
 Emerald green colour
 Distinctive avocado flavour
 Health components present
 Used for culinary purposes
mainly
The Cold Press Extraction Process
Avocado fruit
Water wash
Water
Avocado paste
Paste mixer
(Malaxer)
Pomace
Decanter
Waste water
Centrifuges
Extra virgin oil
Oil storage tank
Bottling
Cold Pressed Extraction of Avocado Oil
 ‘Hass’ main cultivar extracted
 Avocados ripened before oil extraction
 Extraction yield 14-32% oil fresh weight basis
Oil Quality
 Free Fatty Acid (%FFA): Degree of
hydrolysis of oil due to fruit enzymes, lipases.
 Peroxide Value (PV): Oxidation status after
processing and storage.
General Characteristics;
Extra Virgin Oil
Characteristics
Avocado
Olive
FFA (% as oleic)
0.08 - 0.50
0.15 - 0.80
PV (mEq/kg oil)
0.1 – 1.0
1.0 - 2.0
Green-dark green
Yellow-light green
Smoke point
240 - 250°C
180 - 200+°C
Iodine value
(by GC)
82 - 84
75 - 82
Colour
Composition of cold pressed ‘Hass’
avocado oil
Fatty acid
% of total
Palmitic
16:0
12.5 – 14.0
Palmitoleic
16:1
4.0 – 5.0
Stearic
18:0
0.2 – 0.4
Oleic
18:1
70 – 74
Linoleic
18:2
9.0 – 10.0
α-Linolenic
18:3
0.3 – 0.6
Arachidic
20:0
0.1
Gadoleic
20:1
0.1
Research Compounds of Interest
 α - Tocopherol: (Vitamin E) Powerful
antioxidant
 β - Sitosterol: Interferes with cholesterol
absorption hence reducing serum cholestrol
 Carotenoids and Chlorophyll
 Lutein: Concentrates in the macula region of
the eye. Protects from UV and free radicals.
Visual function is improved with lutein.
Antioxidants & Plant sterols
Compound
Avocado
Olive
90 -130
100
β/γ–Tocopherol
15
10
δ–Tocopherol
5
10
Total Vitamin E
(mg/kg)
90 - 200
100 - 150
β–Sitosterol (%)
0.35 – 0.5
0.1 - 0.2
α–Tocopherol
Pigments; Chlorophyll
Average values of Pigments
(μg/g oil)
Pigment
Extra
Virgin
Avocado
Oil
Extra
Virgin
Olive Oil
Refined
Avocado
Oil
Chl a
1.9
0.0
0.0
Chl b
10.6
0.0 - 1.8
0.0
Pigments; Carotenoids
Average values of Pigments
(μg/g oil)
Extra Virgin
Avocado Oil
Extra
Virgin
Olive Oil
Refined
Avocado Oil
Total carotenoids
20 - 31
4 - 12
0
Lutein
17 - 20
4-9
n.d.
Neoxanthin
0-3
0
n.d.
Violaxanthin
2-5
0.1 - 0.4
n.d.
1.5 - 3.0
0.1 - 0.5
n.d.
Pigment
Antheraxanthin
Storage Stability of Avocado Oil
 High in monounsaturated fats
 High in chlorophyll
 Good shelf life stability if stored correctly
 If PV < 1.0 meq/kg, a shelf life of 2 years can
be achieved
Postharvest Procedures
Two fruit storage trials
1. Factory trials to evaluate oil quality
2. Laboratory trials to evaluate quality and
composition
Overall Objective
 Determine the effect of fruit storage on
resulting oil quality and composition
Commercial Factory Trial Results
 Average dry matter at harvest: 26.1%
 Average firmness: Firmometer value: 79
(eating ripe 90 -100 ripe)
 Quality of oil determined from PV and %FFA
results
Laboratory Storage Trial
 Fruit dry matter: 29%
 % FFA
 HPLC analysis
 -sitosterol, - tocopherol
 Lutein
 Total chlorophyll
Results from storage trials
 Storage of fruit for extended periods affects
the resulting oil quality
 Declining levels of healthy compounds
were observed after fruit storage.
 Extraction technique influences yield
Future Research
 Confirm the fruiit postharvest storage effectslarge scale
 Analyse other cultivars, growing regions
 Sensory research
 Lab extraction methodology
 Optimising extraction yields
Thanks to

Funding
– FRST (NZ government)
– TechNZ
– Olivado NZ Ltd