Food Service Systems 08 - Home - The University of Sydneysydney.edu.au/.../Food_Service_Systems_Handouts_08.pdf · Food service systems in NSW hospitals (%) Total 100 100 100 100

1

Food Service Food Service

SystemsSystems

Carmel LazarusNutrition Manager & Consultant Dietitian

Email: [email protected] Ph: 0416482199

February 2008 University of SydneyAcknowledgements: Karen Walton/Associate Professor Peter Williams/Maria

Kokkinakos

ObjectivesObjectives

�� Understand the different types of food Understand the different types of food

production and distribution systemsproduction and distribution systems

�� Recognise the different cook chill systems Recognise the different cook chill systems

availableavailable

�� Understand the advantages and Understand the advantages and

disadvantages of different production and disadvantages of different production and

distribution systemsdistribution systems

Food Service SystemsFood Service Systems

Williams, PG. Journal of the American Dietetic Association 1996; 96(5): p491

Cook Fresh, Cook/Hot hold, Cook Fresh, Cook/Hot hold,

Cook ServeCook Serve

� Advantages

� ‘In house’ quality control

� Less specialised equipment

� Less prepared storage

� Regional buys

� Disadvantages

� Daily, busy meal times

� Workloads vary� Production occurs

over the whole day, every day

Foods are prepared > Held for a short time > Served

Cook FreshCook Fresh

Salads, sandwiches, fresh/cold dairy desserts also in cook chill systems

Cook ChillCook Chill

� Advantages

� Uniform workflow� Menu variety� Reduced

production costs� 5 day production� Area wide menus � Quality control

� Disadvantages

� Specialised equipment

� Storage requirements� Some recipes aren’t

suited� Some foods not

suitable - grills

Foods are prepared > Chilled > Hot or Cold Plating/Retherm

2

EquipmentEquipment

Short shelf life

EquipmentEquipment

Long shelf life

Cook Chill Cook Chill Cook Chill Delivery SystemsCook Chill Delivery Systems

Cook Chill Cook Chill (Bulk heating, hot plating)(Bulk heating, hot plating)

Cook ChillCook Chill(Cold plating, (Cold plating,

rethermretherm))



3

Cook FreezeCook Freeze

� Advantages

� As for cook chill

� Disadvantages

� As for cook chill� Recipe modification

re: thickeners� Thawing step

Foods are prepared > Frozen > Hot or Cold Plating/Retherm

512Combination

422913

186

12

5Cook-chill- external- internal

548193Cook fresh

2001(n=93)

1993(n=179)

1984(n=270)

Food service systems in NSW Food service systems in NSW

hospitals (%)hospitals (%)

Mibey R, Williams P. Food Service Technology 2002; 2:95-103

Food service systems in NSW

hospitals (%)

100100100100Total

9451Combination

1691312Int Cook chill

4711296Ext Cook chill

29775481Cook fresh

2001100beds +

2001<100 beds

2001All

1993All

System

Mibey R, Williams P. Food Service Technology 2002; 2:95-103

Manager’s satisfaction with their foodservice system Mean rating

(1 = very dissatisfied; 10=very satisfied)

5.9**8.1All

5.87.0250+

5.6*7.9100-249

6.28.350-99

7.18.025-49

8.08.70-24

Cook ChillCook FreshHospital size (beds)

Mibey & Williams Food Service Technology 2002;2:95-103

Meal plating location – % NSW hospitals

139114Decentralised

87918996Centralised

2001100+ beds

2001<100 beds

2001All

1993AllLocation


Meal delivery systems% NSW hospitals 2001

21.0Total

1.9Conduction heating

3.8Microwave ovens

4.8Infra-red ovens

10.5Convection ovens

Chilled or Frozen systems

79.1Total

1.9Heated bulk food trolleys

4.7Hot and cold delivery cart

14.3Plate cover only

20.9Heated pellet

34.5Insulated cover and base

Hot delivery systems


4

St Vincent’s CampusSt Vincent’s Campus

SVPH Kitchen

Mental Health

Palliative care & Rehab

D & A

Public Hospital

Delivered in Bulk (heated)Plated on site

Delivered in Bulk HeatedPlated on site

Delivered in Bulk heated using a van

Plated on Site

Centrally platedDelivered in heated and

Refrigerated trolleys

Delivered in bulk

Plated on site

Distribution SystemsDistribution Systems

�� Centralised PlatingCentralised Plating

�� Hot metalHot metal

�� Wax pellet in baseWax pellet in base

�� Insulated plate base & coverInsulated plate base & cover

�� Insulated trayInsulated tray

�� Trolley cart with heat/refrigerationTrolley cart with heat/refrigeration

�� Decentralised PlatingDecentralised Plating

�� Bulk food in chilled/heated trolleysBulk food in chilled/heated trolleys

�� Bulk food in insulated containersBulk food in insulated containers

�� Frozen/chilled food distributedFrozen/chilled food distributed

Distribution Systems cont.Distribution Systems cont.

�� Semi centralised Semi centralised –– food plated centrally and food plated centrally and

distributed for reheatingdistributed for reheating

�� Central tray settingCentral tray setting

�� Decentralised heatingDecentralised heating

�� Specialised TrolleysSpecialised Trolleys

Centralised SystemCentralised System�� AdvantagesAdvantages

�� Labour savingLabour saving

�� Allows meal checking/staff supervisionAllows meal checking/staff supervision

�� Economies of space and equipmentEconomies of space and equipment

�� Saving in overheads Saving in overheads –– maintenance, fuel, cleaningmaintenance, fuel, cleaning

�� Allows batch cookingAllows batch cooking

�� Reduced food wasteReduced food waste

�� Reduced noise on wardsReduced noise on wards

�� Improve menu varietyImprove menu variety

�� DisadvantagesDisadvantages�� More pressure on staff at meal periodsMore pressure on staff at meal periods

�� Must stagger meal hrsMust stagger meal hrs

�� Issues with communication between ward and kitchenIssues with communication between ward and kitchen

�� Physical location of some wards impacts on meal aestheticsPhysical location of some wards impacts on meal aesthetics

Decentralised SystemDecentralised System

�� AdvantagesAdvantages�� Improve motivation/job satisfaction as FS personnel closer to coImprove motivation/job satisfaction as FS personnel closer to consumernsumer

�� Allows last minute changes if food plated in bulk, not for Allows last minute changes if food plated in bulk, not for preplatedpreplated mealsmeals

�� Breaks job tasks down into smaller units so easier to cope withBreaks job tasks down into smaller units so easier to cope with

�� DisadvantagesDisadvantages

�� Difficult to superviseDifficult to supervise

�� Food wastageFood wastage

�� Possible reduction in quality if distributed hot/Physical Possible reduction in quality if distributed hot/Physical

location of some wards impacts on meal aestheticslocation of some wards impacts on meal aesthetics

TrendsTrends

�� Outsourcing Food ProductionOutsourcing Food Production

�� Room Service Room Service

�� Retail Outlets in Hospitals Retail Outlets in Hospitals

�� McCafeMcCafe RPAH,RPAH,

�� Gloria Jeans RNSHGloria Jeans RNSH

5


� Cook Fresh� Cook Chill� Cook Freeze

� Advantages and disadvantages

� Types of equipment

NUTRIENT LOSSESNUTRIENT LOSSES

ObjectivesObjectives

��Understand the how different cooking Understand the how different cooking

and preparation methods affect the and preparation methods affect the

nutrient content of foodsnutrient content of foods

Nutrient lossesNutrient losses

Natural vs ProcessedNatural vs Processed

• Climate• Soil• Handling• Maturity• Feeding regimes

(for animals)• Genetic

• Preparation, milling• Heating• Drying• Chilling• Freezing• Irradiation• Packaging• Storage

Why processWhy process foods?foods?

1. Raw foods are perishable. Processed to preserve, pack or for storage (e.g. canned foods).

2. To produce a desired product (e.g. baked goods).

3. To prepare food for service.

Nutrients can be destroyed when food is processed

due to:

• Sensitivity to the pH of the solvent• Oxygen• Heat • Light and/or any combination.

6 processing principles that 6 processing principles that

preservepreserve

1. Removing moisture (e.g. drying)

2. Treating with heat (e.g. pasteurisation, cook)

3. Cold temperature (e.g. fridge, freezer)

4. Acidity control

5. Chemical additives

6. Irradiation

6

Effects of ProcessingEffects of Processing

Positive vs NegativePositive vs Negative

•• Anti-digestive factorsmay be destroyed

• Increased starchdigestibility

• Bioavailability increased

• Reduced microbial load

• Addition of antioxidants

• Reduction of heat sensitive vitamins

• Vitamins & minerals leached

• Reduced availability of some minerals and amino acids

Stability of nutrientsStability of nutrients

Karmas, E & Harris, RS. 1988, p4

Stability of nutrientsStability of nutrients

• Losses of 60-100% (Unstable)

Vitamin C, folate, biotin, niacin, riboflavin, thiamin

• Losses of 20-60% (Moderately stable)

Vitamin A, B6, D, E, pantothenic acid

• Losses of < 20% (Stable)

Minerals, Amino Acids, Fatty Acids, Vitamins B12and K

Critical nutrientsCritical nutrients

• Vitamins

Vitamins A, B6, C, thiamin, riboflavin and folate Vitamin C and folate most unstable

•• MineralsMinerals

Iron, zinc and calcium

• Dietary fibre

Primary sources of nutrient Primary sources of nutrient

losseslosses

Animal products

• Thaw drip

• Cooking drip

• Leaching

• Cooking & holding losses

Plant products

• Trimming, slicing, soaking

• Leaching

• Heat losses

• Storage

• Reheating

Processing steps in large scale Processing steps in large scale

food servicefood service

• Purchasing

• Storage

• Preparation

• Cooking

• Texture modification

• Chilling

• Chilled storage

• Reheating

• Hot holding

7

Processing steps and lossesProcessing steps and losses

Purchasing (fresh*/frozen/canned*)• Can occur with any type. Greater vitamin loss with canned,

although ‘fresh’ depends on storage time. (e.g. Spinach can lose >50% Vitamin C if at 20°C for 2 days).

• Drying causes significant losses, especially as more water is removed.

Storage• Depends on the time, temperature* and the stability of

temperature.• Frozen & canned products can continue to lose nutrients

(e.g. Vitamin C) in storage, but lower than the initial processing losses.

*Significant loss is possible


Preparation

• Thawing meat can result in significant vitamin losses, especially if in water. Using the fridge or microwave is best.

• Trimming fruits and vegetables increases losses (e.g. oxidation).

• Soaking* also enhances losses (e.g. leaching). Aim to soak or wash for a short time to minimise loss. (Current trend is to utilise pre-prepared salads etc.)


Cooking** Most losses in this stage• Boiling causes greater losses than steaming (Consider

water volume used).• Grill & roasting have smaller losses than braising.• Microwaving, stir frying & steaming seem similar when

using with minimal water.• Baking/frying no significant leaching losses, but greater

vitamin destruction due to the high temperatures.

Chilling• Small losses if chilling is rapid (within 2hrs). Significant

losses if extended (6hrs)*. IHHC Guidelines recommend within 1.5hrs for a gastronorm tray of food.

Processing steps and lossesProcessing steps and lossesChilled storage• Vitamin C is most labile; has a linear loss with time.

Speculation about greater loss in long term cook chill, but lack of 02 may influence.

• Overall, losses still lower in chilled storage, than with hot holding.

Reheating� Smaller loss with individual microwaving.� Large scale food service, usually mass reheating.� Limited data, appears loss is greater when chilled food

heated in bulk, rather than individually- due to the time involved?

� There appears to be no significant differences in losses in reheating, considering infrared, convection, conduction..

Vitamin C loss in chilled storageVitamin C loss in chilled storage



Hot holding**

• Significant losses. Even 30 minutes can cause losses.

• Hot holding should be kept to <90 minutes.

8

Williams, PG et al. 1995: p545

Vitamin C and folate in cookVitamin C and folate in cook--chill chill

and cook/hotand cook/hot--hold systemshold systems

Williams, PG. 1994; p164

Vitamin C and folate in cookVitamin C and folate in cook--chill chill

and cook/hotand cook/hot--hold systemshold systems

• After 1 day chilled storage, then reheating results in a similar effect on Vitamin C to the following hot holding times;• 91 minutes for Vitamin C• 87 minutes for 5MeTHF

• Plated and reheated after 3 days of being in chilled storagewould retain ~28% Vitamin C & 58% 5MeTHF.

• In contrast, hot hold for 2hrs resulted in the retention of ~40.3% Vitamin C and 67.7% 5MeTHF.

• If hot hold <90 minutes, vitamin retention is better in a cook-serve than in a cook-chill system.

Williams, PG et al. 1995

Effects of processing in hospital Effects of processing in hospital

cateringcatering

West, A et al. 1998; p285

• Vitamin C losses increase over the 5 days of storage.• Losses increase with hot holding time. ‘Ideal’ 30 mins.• Awareness of where losses occur, enables better planning.

Loss of Vitamin B6 in hot Loss of Vitamin B6 in hot

holdingholding

• Riboflavin & niacin fairly stable

• Thiamin usually less than 10% loss, for up to 2hrs

• Vitamin C is lost rapidly

• Vitamin B6 is lost• Minimum loss of 10% after 1hr• Up to 40% at 3hrs

Williams, PG, 1996

Canned, Frozen and FreshCanned, Frozen and Fresh

Percentage losses after canningPercentage losses after canning

Nutrient Folacin B1 B2 B3 B6 CAsparagus 75.2 66.7 55 46.6 64 54.5

Carrot 58.8 66.7 60 33.3 80 75

Corn 72.5 80 58.3 47.1 0 58.3

Tomato 53.75 16.7 25 0 - 26.1

Karmas, E & Harris, RS. 1988: p344

9

Percent carotene retention in Percent carotene retention in

stored canned foodsstored canned foodsTemperature 10°C 10°C 18°C 27°C

Months 12 24 24 24

Apricots 94 91 84 76

Carrots 94 90 95 91

Peaches 95 75 64 63

Spinach 91 80 80 81

Tomatoes 94 75 75 74Karmas, E & Harris, RS. 1988: p345-347

Percent ascorbic acid retention Percent ascorbic acid retention

in stored canned foodsin stored canned foodsTemperature 10°C 10°C 18°C 27°C

Months 12 24 24 24

Apricots 96 94 90 56

Pineapple 100 83 78 53

Peaches 98 98 80 53

Asparagus (Gr) 97 93 91 86

Beans (Gr) 92 88 81 74Karmas, E & Harris, RS. 1988: p345-347

Vitamin C in fresh & frozen vegetables

Favell, DJ. Food Chemistry, 1998: p59-64

Peas, Broccoli, Green beans, Spinach, Carrots

Day 0 Garden fresh

Day 3 Ambient Day 3-7 Ambient

Day 2-3 Chilled Day 3-7 Chilled

Day 3-7 Chilled/Ambient

Peas

Peas

0

5101520253035

Garde

n fre

sh

Day 3 A

mbie

nt

Day 3-7

Am

bient

Day 2-3

Chil

led

Day 3-7

Chil

led

Day 3-7

Am

bient

/Chil

led

Froze

n Initia

l

Froze

n 12 m

onths

Type and time of storage

mg

/100g

vit

am

in C

pre

sen

t

Broccoli

Broccoli

0102030405060708090

Garde

n fre

sh

Day 3 A

mbient

Day 3-

7 Am

bien

t

Day 2-

3 Chil

led

Day 3-

7 Chil

led

Day 3-

7 Am

bien

t/Chil

led

Froze

n Initia

l

Froze

n 12 m

onths


mg

/100g

vit

am

in C

pre

sen

t

Spinach

Spinach

0

5

10

15

20

25

30

Garde

n fre

sh

Day 3 A

mbient

Day 3-

7 Am

bien

t

Day 2-3

Chil

led

Day 3-7

Chil

led

Day 3-7

Am

bien

t/Chil

led

Froze

n Initia

l

Froze

n 12 m

onths


mg/1

00g v

itam

in C

pre

sen

t

10

Thiamin content of frozen steak Thiamin content of frozen steak (mg/100g)(mg/100g)

Constant Fluctuating

Temp (+ 1°C) Temp (+ 5°C)

Initial 3.0 3.0

-10°C 2.8 1.8

-20°C 2.9 2.1

-30°C 3.0 2.6

Karmas, E & Harris, RS. 1988: p561Karmas, E & Harris, RS. 1988, p308

Method of cooking broccoli vs Method of cooking broccoli vs

phenolic compound contentsphenolic compound contents• Compared the influence of

cooking methods on phenols in broccoli. 150g broccoli, 150ml water

• (A) High pressure 3 min• (B) Low pressure 5 min• (C) Steaming 3.5 min• (D) Microwaving 5 min

Microwave > Highest losses? Overcooked

Steaming superior- short time & nowater contact

Vallejo, F et al. 2003: p1515

IrradiationIrradiation• Uses

• Controls insects in spices, herbs, nuts & grains

• To reduce the level of bacteria in meat• Minimise sprouting in fruits & vegetables

• Influence on nutrition• Similar vitamin losses to heat processing• No significant impact on carbohydrates,

protein and minerals• May increase fat oxidation

Further research required on phytochemicals & antioxidants

Effect of processing on major flavonoids

in onions

� Significant (50%) reduction with peeling & chopping

� 90% of quercetin (flavonoid) is in the 1st & 2nd

layers

� Fairly heat stable thereafter

Ewald, C et al. Food Chemistry, 1999: p231-235

Blanching & freezing on bioactive

compounds in vegetables

� 20-30% losses of antioxidant activity & total phenolics

� Up to 30% vitamin C lost with blanching

� Up to 50% folate lost

� Carotenoids & sterols stable

Puupponen-Pimia, R et al. Journal of the Science of Food and Agriculture, 2003: p1389-1402

11

In Summary

Recommendations to maximise nutrient retention

Dry Goods

� Store dry goods at <20°C

Fresh goods

� Minimise the time stored� Shop 2-3 times per week, if possible, to optimise

the retention of the nutrient value and appearance� Protect from heat and light�Stable refrigeration temperature� Always wash before use

Recommendations

Frozen foods

� Keep freezer temperatures stable� Thaw in the refrigerator

Preparation

� Cut foods just prior to service

Cooking

� Cook larger vegetable portions� Restrict the time for ‘hot holding’� Use minimal water to cook vegetables� Consider steaming, microwaving and stir frying

Recommendations

� Know where losses occur and plan accordingly

� Include a variety of foods in your day that are rich in critical nutrients (e.g. fresh fruit for vitamin C, legumes andgreen leafy vegetables for folate)

ReferencesReferencesEwald, C, Fjelkner-Modig, S, Johansson, K, Sjöholm, I and Åkesson, B. Effect of processing on major flavonoids in processed onions, green beans, and peas. Food Chemistry 1999; 64(2): p231-235

Favell, DJ. A comparison of the vitamin C content of fresh and frozen vegetables. Food Chemistry 1998; 62(1): p59-64

Hunt, C. Vitamins in institutional feeding. Journal of Micronutrient Analysis 1990; 7:p193-206

Karmas, E & Harris, RS. Nutritional Evaluation of Food Processing (3rd edition). New York: Van Nostrand Reinhold Company Inc; 1988.

Light N & Walker A . Cook-Chill Catering Technology and Management. Elsevier Applied Science: Barking; 1990.

Mibey R & Williams P. Food service trends in New South Wales hospitals, 1993-2001. Food Service Technology 2002; 2:95-103.

Puupponen-Pimiä, R, Häkkinen, S.T, Aarni, M, Suortti, T, Lampi, A.M, Eurola, M, Piironen, V, Nuutila, A.M, Oksman-Caldentey, K.M. Blanching and long-term freezing affect various bioactive compounds of vegetables in different ways. Journal of the Science of Food and Agriculture 2003: 83(14): p1389-1402

Puckett, RP. Food Service Manual for Health Care Institutions (3rd edition). San Francisco: Jossey-Bass; 2004.

ReferencesReferences

Vallejo, F, Tomas-Barberan, FA and Garcia-Viguera, C. Phenolic compound contents inedible parts of broccoli inflorescences after domestic cooking. Journal of Food ScienceAgriculture 2003; 30: p1511-1516

West, A, Walker, A and Lawson, J. The effects of food processing in hospital cateringsystems. Conference Proceedings of ICCAS 98-Culinary Arts and Science II Global andNational Perspectives 1998: p283-289

Payne-Palacio J, Theis M. West & Wood’s Introduction to Foodservice (9th ed). PrenticeHall; 2001.

Williams, PG. Vitamin retention in cook/chill and cook/hot-hold hospital foodservices.Journal of the American Dietetic Association 1996; 96(5): p490-503

Williams, PG, Ross, H. and Brand-Miller, JC. Ascorbic acid and 5-methyl-tetrahydrofolatelosses in vegetables with cook/chill or cook/hot-hold foodservice systems. Journal ofFood Science 1995; 60:p541-546

Williams, PG. Food in Hospitals. PhD thesis. 1994

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