Valorisation of Pea Harvest Residues for use as...
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Valorisation of Pea Harvest Residues for use as Functional Food Ingredients: Post-Harvest Treatment of Pea Haulm for the Preservation of Nutrients Rhianna Briars
Transcript of Valorisation of Pea Harvest Residues for use as...
Valorisation of Pea
Harvest Residues for use
as Functional Food
Ingredients:
Post-Harvest Treatment of
Pea Haulm for the
Preservation of Nutrients
Rhianna Briars
Background
153 kt/year haulm (25000 acre peas)
vines, pods, leaves
Pea-Harvest: Annual 7 weeks Jul-Aug
Valorising Green Leafy Materials:
Chloroplasts
Membrane composed of galactolipids,
high in α-Linolenic Acid
Photosynthesis: Protein complexes of the
thylakoid membranes
Synthesise vitamins, pigments
Current Project Re-SAUCE
Aim: Assess methods of stabilising nutrients
• Explore Blanching and Juice Treatment Techniques:
Simply determine effectiveness of treatment techniques:
Aesthetically and using an Enzyme Assay
o Blanching
Steam: time, temperature
Water: time, temperature
Microwave: time, power
o Juice Treatment
Pasteurisation: time, temperature
Anti-oxidants: inhibitor, concentration
Material Treatment
Blanch
Freeze (store 2 month)
Juice
Pasteurise
Antioxidant addition
CRF extraction
Freeze Dry
Store Dried (1 month)
Store Dried (2 month)
Trials
Enzyme Assay
Peroxidase (POD): popular indicator enzyme for vegetable heat treatments
heat stability
Active in plant stress: counteract release of ROS
Colorimetric assay:
Colour change due to oxidation of Guaiacol
In presence of H2O2
> enzyme activity = faster colour change
Biomass Treatments
Treatment Conditions Enzyme Knock-out
No Treatment n/a
Hot Water Blanch 80°C (2 mins) 93%
Microwave Blanch 1.5 mins 84%
Steam Blanch 1 min 55%
Steam Blanch 2 min 59%
Steam Blanch 4 min 70%
Large Scale Steam Blanch 100°C at 1 bar1 min sterilisation
49%
Large Scale Steam Blanch 100°C at 1 bar4 min sterilisation
81%
Untreated
4 min Retort
Juice Treatments
Treatment Enzyme Knock-out
No Treatment n/a
2.5 mg/ml Chlorogenic Acid 18%
70°C Pasteurisation (3 mins) Increased POD activity
70°C Pasteurisation (3 mins)With chlorogenic acid
8%
70°C Pasteurisation (6 mins) 42%
70°C Pasteurisation (6 mins)With chlorogenic acid
90%
90°C Pasteurisation (3 mins) 60%
90°C Pasteurisation (3 mins)With chlorogenic acid
86%
90°C Pasteurisation (6 mins) 87%
90°C Pasteurisation (6 mins)With chlorogenic acid
98%
Treatment Trial
Pea Harvest: 17th July 2017
FRESH Frozen (2) BLANCHEDBlanched
Frozen (2)PASTEURISED
Blanch
Freeze (store 2 month)
Juice *POD *POD *POD *POD
Pasteurise *POD
CRF extraction
Freeze Dry *Nutr. *Nutr. *Nutr. *Nutr. *Nutr.
Store Dried (1 month) *Nutr. *Nutr. *Nutr. *Nutr. *Nutr.
Store Dried (2 month) *Nutr. *Nutr. *Nutr. *Nutr. *Nutr.
Material Treatment
Trials
Treatment Trial: Methodology
Fractionate
Fractionate
Fractionate Dry
Dry
Dry
Macronutrient Content
Fresh
Blanched (4 minute Retort)
Pasteurised (3 minute at 90°C)
↓55%
↓75%
↓34%
POD enzyme knockout
Steam Blanch: 66%; Pasteurised Juice: 100%
Micronutrient Storage Trial
↓23%
↓91-94%
0
1
2
3
4
5
6
7
8
Fresh Blanched Pasteurised
Lute
in C
on
cen
trat
ion
(m
g/g
CR
F D
W) Week 0 Week 4 Week 8
0
0.2
0.4
0.6
0.8
1
1.2
Fresh Blanched Pasteurisedβ
-Car
ote
ne
Co
nce
ntr
atio
n(m
g/g
CR
F D
W)
Week 0 Week 4 Week 8
0
0.1
0.2
0.3
0.4
0.5
0.6
Fresh Blanched Pasteurised
α-T
oco
ph
ero
l Co
nce
ntr
atio
n(m
g/g
CR
F D
W)
Week 0 Week 4 Week 8
Biomass Storage
POD enzyme reduction
Frozen vs. Blanched Frozen
2 Month: 80%
↓93%
↓46%
↓32%
Summary
• Steam Blanching pea haulm or Pasteurising extracted juice
knocks out POD enzymes:
o Starch appears to be gelatinised due to the heat treatment and the
prolonged heating during pasteurisation may denature proteins
o The micronutrient content is not overtly reduced
• During storage α-tocopherol and β-carotene appear to be stable irrespective of
treatment, whereas lutein suffers degradation
• The POD knock-out is retained during frozen storage (2 months):
o Freeze storing untreated pea haulm causes a break down in micronutrients
- particularly α-tocopherol
o POD knock-out seems to protect from this nutrient break down
Conference
Systems Change Thinking –
Creating Value from Unavoidable Food Supply Chain Wastes
Tuesday 16th January 2018
University of Nottingham,
Sutton Bonington Campus
https://foodwaste-systemschange.eventbrite.com
Valorisation of Pea
Harvest Residues for use
as Functional Food
Ingredients:
Post-Harvest Treatment of
Pea Haulm for the
Preservation of Nutrients
Rhianna Briars
