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Efectos de Procesamiento en la Calidad Nutricional
de Frutas y Hortalizas
Dr. Diane M. BarrettFruit & Vegetable Products Specialist
University of California – Davis
Outline of Presentation• Fruits and Vegetables – What’s the
Difference? • Fruit & Vegetable Composition
(Macro- and Micronutrients)
• Effects of Various Preservation Technologies on Fruit/Vegetable Nutrients – 3 Studies• 2007 JSFA – fresh, canned, frozen (lit review)• 2012 JSFA – fresh, HPP, MW (lit review)• 2015 JAFC – fresh and frozen (original work)
Fruits & VegetablesWhat’s the Difference?
1. Botanical
1. Fruit = plant structures that contain seeds
2. Vegetables = other edible part of a plant (leaf, stem, root)
2. Chemical
1. Fruits = more acid and sugar, often less fiber
2. Vegetables = less overall flavor – if any it may be ‘bitter’
3. Physical
1. Fruits = more delicate, may require seed removal. Maintaining structure difficult, except if freeze dry.
2. Vegetables = more durable, need for peeling in some cases. More lignin/cell wall and structural integrity.
FigPeduncle
StrawberryReceptacle
MangosteenAril
Pomegranateseed
Outer layer Of the testa
PeachMesocarp
OrangeEndodermalIntralocular tissue
GrapesPericarp
Tomato
Placental intralocular tissue
Septum
PineapplePeduncle
Pedicel
Cashewapple
Spinachleaf blade
Leekswollen leaf base
Potatostem tuber
Carrotswollen tap root
Beetswollen hypocotyl
OnionBulb (underground bud)
BrusselsSproutsAxillary bud
AsparagusStem sprout
ArtichokeFlower bud
Broccoliswollen inflorescence
Celerypetiole
Lettucemain bud
*Less than 2% dry weight. Despite trace levels, an important source of vitamins & minerals
Fruit & Vegetable Composition
Water
Carbohydrate
Protein
Fats
Vitamins
Minerals
70-90%
4-20%
< 3.5%
<0.5%
trace *
trace *
Key Classes of F/V Nutrients Water Soluble
• B Vitamins• B1 – Thiamin• B2 – Riboflavin• B3 - Niacin• B6 – Pyridoxal• B9 – Folic acid
• Vitamin C• Phenolics
• Total• Specific
• Anthocyanins• Minerals • Fiber
Lipid Soluble
• Vitamin A• Vitamin E• Carotenoids
• Total• Specific
Dietary Reference Intakes (Institute of Medicine)
Vit A(RDA)
Vit B1
Vit B2
Vit B3
Vit B6
Folate
Vit C Vit E Ca K Na(AI)
Fiber(AI)
RDA/AI(mg/day)
0.80 1.15 1.2 15 1.3 0.40 82.5 15 1000 4.7 1.5 30
EAR (mg/day)
0.56 0.95 1.0 11.5 1.2 0.32 67.5 12 - - - -
RDA = Recommended Daily Allowance (in 1997 these broadened into DRIs)AI = Adequate IntakeEAR = Estimated Average RequirementDRI = Dietary Reference Intakes, from Institute of Med & US National Academy Sci FDA defines a “good source” of a nutrient as one serving of food containing 10 to 19% of the RDA or AI for that nutrient. DRIs refer to intake recommendations for various nutrients and include the aforementioned RDA and AI in addition to Estimated Average Requirement (EAR) and Tolerable Upper Intake Level (UL). EARs are based on the daily requirements of 50% of healthy individuals in a particular group, while RDAs are set slightly higher to meet the needs of most (97-98%) individuals.
Suggested Nutrient Focus?
• Those that have established DRIs• Vitamin A Vitamin E• Vitamin B1 Calcium• Vitamin B2 Potassium• Vitamin B3 Sodium• Vitamin B6 Fiber• Vitamin B9 (folate)• Vitamin C
Current nutrition label based on older Reference Daily Intakes.
Fruit & Vegetable Sources - Vitamins & Minerals Nutrient EAR
RDA/AI
UL Unit Top Sources in Common Measures, USDA
Vitamin A 625 900 3000 µg carrot juice, pumpkin
Vitamin C 75 90 2000 mg orange juice, grapefruit juice, peaches
Vitamin K NE 120 ND µg kale, collards, spinach
Vitamin B6 1.1 1.3 100 mg fortified cereals, chickpeas
α-Tocopherol(Vitamin E)
12 15 1000 mg fortified cereals, tomato paste, sunflower seeds
Folate (B9) 320 400 1000 µgenriched white rice, fortified cereals, enriched cornmeal
Molybdenum 34 45 2000 µg legumes, grain products, nuts and seeds[8]
Niacin (B3) 12 16 35 mg fortified cereals
Potassium NE 4700 ND mg tomato paste, orange juice, beet greens
Riboflavin (B2) 1.1 1.3 ND mg spaghetti with meat sauce
Thiamin (B1) 1.0 1.2 ND mg fortified cereals
USDA National Nutrient Database, SR 23, 2010.
Stability of Nutrients in Processed Foods• Source: Klein and Kurilich, HortScience 1998
Nutrient
Neutral Acid Basic Oxygen Light Heat Water
Beta-Carotene
S SU S U U SU Slight sol
Vitamin C U S U U U U UU
Thiamin U S UU U S U U
Riboflavin S S U S UU SU SU
Folate U U S S U S SU
Minerals S S S S S S S
Vitamin E S SU S UU U SU insoluble
Effect of pH Effect of Environment
S=stable; SU=slightly unstable; U=unstable; UU=very unstable
Effects of Various Preservation Methods on Fruit & Vegetable Nutrients
• Summary of Literature Reviews: • 2007 JSFA – Fresh, Canned, Frozen
• Part I = Vitamin C, B, and phenolics• Part II = Vitamin A and carotenoids,
Vitamin E, minerals and fiber
• 2012 JSFA – HPP and Microwave• Vitamin A, B1, B2, B3, B6, B9, C, E• Phenolics, anthocyanins, carotenoids
• 2015 JAFC – Fresh and Frozen• Part I =Vitamins• Part II = Minerals, Fiber & Phenolics
2007 Publications
Fresh, Canned & Frozen
Fruits and Vegetables
Vitamin C - Fresh• Ascorbic acid degrades rapidly after harvest• Degradation continues during storage• Refrigeration slows loss
• Broccoli 7 days storage56% loss at 20 degrees C
0% loss at 4 degrees C
Vitamin C - Freezing• Loss ranges from 10-80%• Broccoli, peas, 20-30% loss• Retention depends on cultivar,
processing conditions.• Storage – 20-50% average loss after 1 year
(broccoli and spinach). Primarily due to temperature fluctuations – freeze/thaw and cell rupture, oxygen exposure.
• Greater retention in asparagus, peas. • Losses prevented by temperature control,
reducing storage period.
Vitamin C - Summary
• Fresh retains most, if eaten as soon as possible
• Canned, higher initial loss, minimal loss in storage at room temperasture
• Frozen, some loss initially, loss during storage if temperature not controlled
• USDA – similar levels for cooked fresh, canned, and frozen
B Vitamins - Summary
• B vitamins - sensitive to heat used in canning and storage at temperature higher than refrigeration.
• Inconsistencies with methodology and data reporting; difficult to draw conclusions.
• Considering that there are 5 B Vitamins with DRIs, very few studies have evaluated these. More research needed!
Vitamin A and Carotenoids - Canning
• Canning may improve extraction of carotenoids from cellular matrix
• Thermal processing causes a decrease in β-carotene (peaches etc.)
• Lycopene is less heat sensitive than β-carotene
• Processed tomatoes have more lycopene than fresh
Lycopene in Tomato Products (mg/100g wet weight)
6.5
7.7
11
9
0
2
4
6
8
10
12
Fresh CannedWhole
CannedDiced
Puree
Nagarajan et al 1999Note puree is 12 Brix.
Minerals and Fiber
• Calcium, Sodium, Potassium• Natural mineral content retained• Fresh, canned, frozen are similar• Vegetables canned without added sodium
have similar levels as fresh and frozen• No significant change in fiber due to
freezing or canning
Conclusions – Canned Food Alliance Lit Review• Current research on nutritional changes due to
postharvest handling and freezing, storage and cooking is sorely lacking.
• Few studies in the literature followed the same commodity from harvest through processing, storage and cooking.
• The effects of processing, storage and cooking are highly variable by commodity; within a commodity there are varietal and growing practices.
• Nutrient changes are often reported on wet rather than dry weight basis. F/V moisture contents change after harvest therefore the nutrient data is confounded with changes in moisture if expressed on wet weight basis.
120 media placements and more than 10 million viewers from CFA study.
2012 JFSA Publication
Fresh, HPP and Microwave
Fruits and Vegetables
2012 JFSA Literature Review• Focus on effects of HPP and Microwave
on nutrient content in fruits/vegetables• 3 databases: Agricola, CAB and FSTA• 1997 – 2010 publications• 734 references found• Abstracts of each reviewed, 124 found most
pertinent, those reviewed in detail• 29 found to be most significant for HPP• 15 most significant to MW, 11 to MW drying
HPP Manuscripts – General Remarks
• Most pubs focused on Vitamin C and carotenoids; few on B vitamins.
• Only 7/29 reported nutrients on dry weight basis.
• Most studies on juice; few on f/v pieces.• Comparative technology – typically thermal,
but few stated target (m.o., nutrient, enzyme)• 1 report on fiber, none on minerals or lipids.
HPP – Summary of Specific Effects• Vitamins B1, B2 and B6 – few studies,
however results show high retention • Vitamin B9 (folate) – unclear results• Vitamin C – contradictory - oxygen and
oxidative enzymes not controlled; however retention better than thermal treatment
• Carotenoids stable to HPP, may increase• Phenolics unaffected by HPP, may increase• Total fiber unaffected, some solubilization
2012 HPP Effects – Vitamins A & BVitamin
Commodity and Product
Wet vs Dry basis High Pressure Conditions % Loss % Gain Range
VITAMIN A persimmon puree wet 350 MPa/5 min 45 (+45)
VITAMIN B1 (thiamin)
model soln & juices wet 400-600 MPa/25°C/30 min 0-1 0
VITAMIN B2 (riboflavin)
model soln & juices wet 400-600 MPa/25°C/30 min 0-1 0
VITAMIN B3 (niacin)
OJ & seeds wet 200-500 MPa/30°C/1-10 min 0 0
VITAMIN B5 (pantothenic acid)
sprouted alfalfa seed wet 500 MPa/25°C/10 min 0 0
VITAMIN B6 (pyridoxal)
model soln & juices wet 400-600 MPa/25°C/1-30 min 0 0
VITAMIN B9 (folic acid)
model solution wet 400-600 MPa/25°C/5-40 min 0 0-90various juices wet 500 MPa/20-60°C/40 min 0-90
2012 HPP Effects – Vitamin CVitamin
Commodity and Product
Wet vs Dry basis High Pressure Conditions % Loss % Gain Range
VITAMIN C
buffer solution wet 850/60°C/6 hr 100
apple-broccoli juice wet 500 MPa/5 min 3
apple-broccoli juice wet 500 MPa/20 min 28
green beans (whole) wet 500 MPa/25°C/1 min 8
green peas (whole) wet 900 MPa/20°C/5-10 min 12
green peppers wet 100-200 MPa/10-20 min 10 to 15
kiwi-strawberry jam wet 400-600 MPa/10-30 min 0-5
melon pieces wet 600 MPa/10 min 50-90
orange juice wet 100 MPa/60°/5 min 10
orange juice wet 400 MPa/40°C/1 min 5 to 8
orange juice wet 350 MPa/30°C/2.5 min 0
red peppers wet 100-200 MPa/10-20 min 10 to 15
strawberry puree wet 600 MPa/30°C/15 min 6
tomato puree wet 400 MPa/40°C/15 min 29
tomato puree wet 600 MPa/20°C/15 min 6
2012 HPP Effects – CarotenoidsVitamin
Commodity and Product
Wet vs Dry basis High Pressure Conditions % Loss % Gain Range
CAROTENOIDS
α-carotene carrot (whole) wet 600 MPa/25°C/2 min 00-72 (+34)
carrot juice wet 500 MPa/25°C/10 min 50orange juice wet 400 MPa/40°C/1 min 34
orange-lemon-carrot juice wet 500 and 800 MPa/25°C/5 min 0
β-carotene broccoli (whole) wet 600 MPa/25°C/2 min 17
carrot (whole) wet 600 Mpa/25°C/2 min 0 0-60
(+1-30) carrot juice wet 500 MPa/25°C/10 min 40 orange juice wet 400 MPa/40°C/1 min 30
β-cryptoxanthan orange juice wet 400 MPa/40°C/1 min 43 (+43)
Lutein broccoli (whole) wet 600 MPa/25°C/2 min 10 0-10 (+75) green beans wet 600 MPa/25°C/2 min 0 orange juice wet 400 MPa/40°C/1 min 75
Lycopene tomato puree wet 600 MPa/25°C/60 min 0tomato puree wet 500 MPa/20°C/2 min 60tomato puree wet 400 MPa/25°C/15 min 49
Zeaxanthan orange juice wet 400 MPa/40°C/1 min 45 (+45)
Total carotenoids carrot puree wet 600 MPa/20°C/15 min 58 (+8-58)
2012 HPP Effects – PhenolicsVitamin
Commodity and Product
Wet vs Dry basis High Pressure Conditions % Loss % Gain Range
PHENOLICS
catechins apple juice 400 MPa/10 min 290 (+290)
dihydrochalcones apple juice wet 400 MPa/10 min 0 0
apple juice wet 400 MPa/10 min 31 (+31)
procyanidins apple juice wet 400 MPa/10 min 170 (+170)
cyanidin-3-glucoside model solution wet 600 MPa/20°C/30 min 0 0
blackberry puree wet 600 MPa/30°C/15 min 0
quercitin-4'-glucoside onion dry 400 MPa/5°C/5 min 33 (+33)
quercitin-3,4'-diglucoside onion dry 100-400 MPa/5°C/5 min 17 (+17)
Total quercitin onion dry 100-400 MPa/5°C/5 min 26 (+26)
Total phenolics blackberry puree wet 600 MPa/30°C/15 min 10 (+10-100)
longan powder dry 500 MPa/30°C 100
onion dry 100-400 MPa/5-50°C/5 min 12
strawberry puree wet 600 MPa/30°C/15 min 10
tomato puree wet 600 MPa/20°C/15 min 0
Microwave – Summary of Vitamin Effects
• Few papers on Vitamins A and B.• Vitamin C papers focus on f/v pieces,
only 1 paper on orange juice. • Microwave processing generally less
damaging than thermal to Vitamin C. • Exception – OJ lower in Vit C with MW. • MW drying resulted in higher Vit C than
traditional air drying.
MW – Summary of Specific Effects• Total phenolics retained better in MW f/v
pieces if MW power not too high.• Freeze dry >MW vacuum dry > air dry
for total phenolics. • MW f/v retained as much
or > carotenoids than fresh or frozen. • Mineral content similar in sun and MW dry.• Fiber retention fairly good in MW dry.
2012 Microwave – Vitamins A, B, CVitamin
Commodity and Product
Wet vs Dry basis Microwave Conditions % Loss % Gain
Range % Loss or (Gain)
VITAMIN A apricots wet 50-60 Hz, 50-160°C ~250 (+260)
VITAMIN B1 (thiamin) swiss chard wet no information 60 32-60
green beans wet no information 32VITAMIN B2
(riboflavin) swiss chard wet no information 9 9 to 47green beans wet no information 47
VITAMIN C
apple puree wet 2450 MHz, 652 W, 15-60°C, 35 s 570-57 (+10-
260) apricots wet 50-60 Hz, 50-160°C ~260broccoli wet 700 W, 9 min 0brussels sprouts wet 700 W, 5 min, 74°C 10 to 15carrots wet 700 W, 9 min 120-130carrots wet 2450 MHz, 4 kW, 50°C 35green beans wet 700 W, 9 min 117orange juice wet 245-455 W, 0.5-15 min, 100-125°C 30-50peas wet 750 W, 2 min 13spinach wet 750 W, 2.t min 106tomatoes wet 700 W, 4 min 10
2012 Microwave - CarotenoidsCAROTENOIDS
Commodity and Product
Wet vs Dry basis Microwave Conditions % Loss % Gain
Range % Loss or (Gain)
β-carotene carrots wet 1000 W, 60°C-90 min or 90°C-4 min 0 0-75
carrots wet 2450 MHz, 4 kW, 50°C 30
kiwi puree wet 2450 Mz, 285, 570 and 850 W, 15-60 s 75
chlorophyll brussels sprouts wet 700 W, 5 min, 74°C 8 8 to 75
kiwi puree wet 2450 Mz, 285, 570 and 850 W, 15-60 s 25-75
lycopene cherry tomatoes wet 1-33 W/gram, 40-80°C 86 86
Total Carotenoids papaya puree wet 2450 Mz, 285, 570 and 850 W, 15-60 s 0 to 57 0-57
2012 Microwave - PhenolicsPHENOLICS
rutin asparagus wet 915 MHz, 121°C, 3 min 0 0protocatechuic acid unpeeled potato wet 2450 MZ, 150-1000 W, 95-420 min 14 to 26 14-84
peeled potato wet 2450 MZ, 150-1000 W, 95-420 min 50 to 84caffeoylquinic acid unpeeled potato wet 2450 MZ, 150-1000 W, 95-420 min 6 to 60 6 to 65
peeled potato wet 2450 MZ, 150-1000 W, 95-420 min 23 to 65pelargonidin-3-
glucosides strawberry puree wet 2450 Mz, 285, 570 and 850 W, 15-60 s 0 0Total anthocyanins
kiwi puree wet 2450 Mz, 285, 570 and 850 W, 15-60 sstrawberry puree wet 2450 Mz, 285, 570 and 850 W, 15-60 s 0sweet potato wet 915 kW, 5 kW and 60 kW 15
Total flavonoidsbrussels sprouts wet 700 W, 5 min, 74°C 15 15
Total phenolics
apple puree wet 2450 Mz, 652 W, 75°C, 35 sec 570-57 (+104-
125)carrots dry 800 W, 6 min 125cauliflower dry 800 W, 8 min 114peas dry 800 W, 5.5 min 39potato dry 800 W, 6.5 min 107potato wet 2450 MZ, 150-1000 W, 95-420 min 4 to 32spinach dry 800 W, 6.5 min 42sweet potato wet 915 kW, 5 kW and 60 kW 105-108Swiss chard dry 800 W, 6.5 min 86tomato dry 800 W, 3 min 91
2015 JAFC Publications
Fresh and FrozenFruits and Vegetables
Ali Bouzari, PhD Candidate
Experimental Design
6 field replicates
Commodities
• Carrots August 2012• Spinach December 2012• Broccoli February 2013• Blueberries March 2013• Peas April-May 2013• Green Beans June 2013• Strawberries July 2013• Corn August 2013
Ascorbic Acid
• Fresh storage: Blueberries, green beans, and corn lost AA
• Frozen storage: No losses • Higher*: blueberries, green beans, and corn• Same as fresh: strawberries, carrots, peas,
spinach, broccoli• Lower: none
• *Blanched + Frozen Day 90 vs. Fresh Day 10
Ascorbic Acid – Strawberries
0 3 10 90400
420
440
460
480
500
520
540
AB
B
AB
B
B
A
Fresh Frozen
Days
Asc
orb
ic A
cid
(p
pm
)
Ascorbic Acid – Green Beans
0 3 10 90 0
200
400
600
800
1000
1200
B
C
D
AB A AB
Fresh Frozen
Days
Asc
orb
ic A
cid
(p
pm
)
b
Riboflavin
• Fresh storage: Increases in corn and broccoli
• Frozen storage: Losses in peas• Higher : Broccoli• Same as fresh: Carrots, corn, green beans,
broccoli, blueberries, strawberries• Lower: Peas
Riboflavin – Green beans
0 3 10 90 5.60
5.80
6.00
6.20
6.40
6.60
6.80
A
A
AA
A
A
Fresh Frozen
Days
Rib
ofla
vin
(p
pm
)
Riboflavin – Peas
0 3 10 90 0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
A A AA A
B
Fresh Frozen
Days
Rib
ofla
vin
(p
pm
)
Alpha Tocopherol
• Fresh storage: Losses in peas, carrots A, corn• Frozen storage: Losses in broccoli, carrots B• Higher: peas, green beans, spinach
blueberries, corn (blanching releases?)• Same as fresh: broccoli, carrots B, and
strawberries• Lower: None
Alpha Tocopherol – Peas
0 3 10 90 0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
BBC
C
A A A
Fresh Frozen
Days
Alp
ha
Toc
oph
erol
(p
pm
)
b
Alpha Tocopherol – Broccoli
0 3 10 90 0.00
50.00
100.00
150.00
200.00
250.00
C C
B
A
B B
Fresh Frozen
Days
Alp
ha
Toc
oph
erol
(p
pm
)
Beta Carotene
• Not found in blueberries, strawberries, and corn• Fresh storage: Losses in peas, green beans,
and carrots• Frozen storage: Losses in peas, spinach, and
carrots• Higher: None• Same as fresh: green beans and broccoli• Lower: peas, spinach, and carrots
Beta Carotene – Carrots
0 3 10 90 0.0
200.0
400.0
600.0
800.0
1000.0
1200.0
1400.0
1600.0
AAB
BCCD
D
E
Fresh Frozen
Days
β-ca
rote
ne
(pp
m)
a
Beta Carotene – Green beans
0 3 10 90 0.0
5.0
10.0
15.0
20.0
25.0
B B
AA
AA
Fresh Frozen
Days
Bet
a C
arot
ene
(pp
m)
Fiber
• Fresh storage: Increase in broccoli• Frozen storage: Losses in carrots• Higher: none• Same as fresh: blueberries, strawberries,
spinach, and corn• Lower: carrots, peas, green beans, broccoli
Fiber - Blueberries
0 3 10 90 5.8
6.0
6.2
6.4
6.6
6.8
7.0
7.2
AA
AB
BCC
AB
Fresh Frozen
Days
Fib
er (
%)
Fiber - Broccoli
0 3 10 90 0.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
B B
A
B BB
Fresh Frozen
Days
Fib
er (
%)
a
Phenolics
• Fresh storage: Increases in peas, spinach, and broccoli; losses in carrots and corn.
• Frozen storage: Losses in peas, carrots, and corn
• Higher: blueberries• Same as fresh: spinach, green beans,
carrots• Lower: broccoli, corn, peas
Phenolics - Spinach
0 3 10 90 0.00
2.00
4.00
6.00
8.00
10.00
12.00
B
A AB
A A
Fresh Frozen
Days
Tot
al P
hen
olic
s (m
g G
AE
/g)
Phenolics – Corn
0 3 10 90 0.00
0.50
1.00
1.50
2.00
2.50
3.00
AA
B
AA
C
Fresh Frozen
Days
Tot
al P
hen
olic
s (m
g G
AE
/g)
b
Minerals
• Minerals can only be lost during blanching• Most commodities retained minerals well
• Slight losses in magnesium• Iron losses most significant
Conclusions• For most nutrients, frozen presents a viable
alternative to fresh.• Riboflavin, alpha tocopherol, ascorbic acid and
minerals were well conserved and at times their content was higher in blanched and frozen stored fruits & vegetables than in fresh stored produce.
• Fiber and phenolics content in frozen stored produce were similar to fresh in some commodities.
• Beta carotene was least well conserved in blanched and frozen stored fruits & vegetables.
• Follow up studies on effects of food preparation in the home are recommended.
Thanks for your attention!