1、16.1CHAPTER 16FOOD SERVICE AND GENERAL COMMERCIAL REFRIGERATION EQUIPMENTRefrigerated Cabinets . 16.1Food Freezers . 16.3Blast Chillers and Blast Freezers . 16.3Walk-In Coolers/Freezers . 16.3Vending Machines. 16.5Ice Machines . 16.6Preparation Tables 16.7OOD service requires refrigerators that meet
2、 a variety of needs.FThis chapter covers refrigerators available for restaurants, fast-food restaurants, cafeterias, commissaries, hospitals, schools, con-venience stores, grocery stores, and other specialized applications.Many refrigeration products used in food service applications areself-contain
3、ed, and the corresponding refrigeration systems are con-ventional. Some systems, however, do use ice for fish, salad pans, orspecialized preservation and/or display. Chapters 15 and 17 havefurther information on some of these products.Generally, electrical and sanitary requirements of refrigeratorsa
4、re covered by criteria, standards, and inspections of UnderwritersLaboratories (UL), NSF International, and the U.S. Public HealthService.REFRIGERATED CABINETSReach-In CabinetsThe reach-in refrigerator or freezer is an upright, box-shapedcabinet with straight vertical front(s) and hinged or sliding
5、doors(Figure 1). It is usually about 750 to 900 mm deep and 1800 mmhigh and ranges in width from about 900 to 3000 mm. Capacitiesrange from about 500 to 2500 L. Undercounter models 900 mm highwith the same dimensions are also available. These capacities anddimensions are standard from most manufactu
6、rers.The typical reach-in cabinet is available in many styles and com-binations, depending on its intended application. Other shapes,sizes, and capacities are available on a custom basis from somemanufacturers. Chapter 15 discusses display cabinets in great detail.There are many varied adaptations o
7、f refrigerated spaces for stor-ing perishable food items. Reach-ins, by definition, are medium- orlow-temperature refrigerators small enough to be moved into abuilding. This definition also includes refrigerators and freezersbuilt for special purposes, such as mobile cabinets or refrigeratorson whee
8、ls and display refrigerators for such products as beverages,pies, cakes, and bakery goods. The latter cabinets usually have glassdoors and additional lighting to illuminate the product. Candyrefrigerators are also specialized in size, shape, and temperature.Refrigerated vending machines satisfy the
9、general definition ofreach-ins; however, because they also receive coins and dispenseproducts individually, they are classified separately. Generally, thefull product load of a vending machine is not accessible to the cus-tomer as in normal reach-in cabinets. Beverage-dispensing units dis-pense a me
10、asured portion into a cup rather than in a bottle or can.Reach-in refrigerators have doors on the front. Refrigerators thathave doors on both front and rear are called pass-through or reach-through refrigerators (Figure 2). Doors are either full height (oneper section) or half height (two per sectio
11、n). Doors may have win-dows or be solid, hinged, or sliding.Roll-In CabinetsRoll-in cabinets are very similar in style and appearance toreach-in cabinets, but vary slightly in construction and functional-ity. Roll-ins (Figure 3) are usually part of a food-handling or otherspecial-purpose system (Fig
12、ure 4). Pans, trays, or other speciallyThe preparation of this chapter is assigned to TC 10.7, Commercial Foodand Beverage Cooling, Display, and Storage.Fig. 1 Reach-In Food Storage Cabinet FeaturesFig. 1 Reach-In Food Storage Cabinet FeaturesFig. 2 Pass-Through Styles Facilitate Some Handling Situa
13、-tionsFig. 2 Pass-Through (Reach-Through) Refrigerator16.2 2010 ASHRAE HandbookRefrigeration (SI)sized/shaped receptacles are used to serve a specific system need,such as the following: Food handling for schools, hospitals, cafeterias, and other institu-tional facilitiesMeal manufacturingBakery proc
14、essingPharmaceutical productsBody parts preservation (e.g., blood)The roll-in differs from the reach-in in the following ways:The inside floor is at about the same level as the surrounding roomfloor, so wheeled racks of product can be rolled directly from thesurrounding room into the cabinet interio
15、r.Cabinet doors are full height, with drag gaskets at the bottom.Cabinet interiors have no shelves or other similar accessories.Product TemperaturesRefrigerators are available for medium- or low-temperatureranges. The medium-temperature range has a maximum of 5C anda minimum of 1C core product tempe
16、rature, with the most desir-able average temperature close to 3C. Low-temperature refrig-erators cover a range of core product temperatures between 23 and12C. The desirable average core product temperature is 18C forfrozen foods and 20.5C for ice cream. Both temperature rangesare available in cabine
17、ts of many sizes, and some cabinets combineboth ranges.Typical ConstructionRefrigerators are available in two basic types of construction.The older style is a wood frame substructure clad with a metal inte-rior and exterior. The newer style is a welded assembly of exteriorpanels with insulation and
18、liner inserts.Exterior. Materials used on exteriors (and interiors) are stainlesssteel, painted steel, aluminum-coated steel, aluminum, and vinyl-clad steel with wood grain or other patterns. The requirements arefor a material that (1) matches or blends with that used on nearbyequipment; (2) is easy
19、 to keep clean; (3) is not discolored or etchedby common cleaning materials; (4) is strong enough to resist dent-ing, scratching, and abrasion; and (5) provides the necessary framestrength. The material chosen by an individual purchaser depends agreat deal on layout and budget.Interior. Shelves, usu
20、ally three or four per full-height section,are standard interior accessories. Generally, various types of shelfstandards are used to provide vertical shelf adjustment.Racks for roll-in cabinets are generally fitted with slides to handle460 by 660 mm pans, although some newer systems call for either3
21、00 by 510 mm or 300 by 460 mm steam table pans. Racks designedfor special applications are available but usually custom designed.Manufacturers and contractors offer various methods of floorinsulation. This is important if the roll-in holds frozen food.Specialty ApplicationsReach-in and roll-in cabin
22、ets are regularly modified and adaptedto fit the needs of many specialty applications. Variations from stan-dard construction practices are needed to meet the different temper-ature, humidity, product volume, cleanliness, and other specificationsof various refrigeration applications.Food Service. Th
23、ese applications often require extra shelves ortray slides, pan slides, or other interior accessories to increase food-holding capacity or make operation more efficient. Because certainstored foods create a corrosive atmosphere in the enclosure, theevaporator coil may have special coatings or fin ma
24、terials to pre-vent oxidation. As use of foods prepared off-premises increases,on-site storage cabinets are becoming more specialized; there isgrowing pressure for designs that consider new food shapes, aswell as in-and-out handling and storage.Beverage Service. If reach-ins are required, standard c
25、abinets, areused, except when glass doors and special interior racks are neededfor chilled product display. These cabinets generally have oversizedrefrigeration systems to allow for product pulldown cooling.Meal Factories. These applications, which include airline orcentral feeding commissaries, req
26、uire rugged, heavy-duty equip-ment, often fitted for bulk in-and-out handling.Retail Bakeries. Special requirements of bakeries are the doughretarder refrigerator and the bakery freezer, which allow the baker tospread the work load over the entire week and to offer a greater vari-ety of products. Th
27、e recommended temperature for a dough retarderis 2 to 4.5C. The relative humidity should be in excess of 80% toprevent crusting or other undesirable effects. In the freezer, the tem-perature should be held at 18C. All cabinets or wheeled racksshould be equipped with racks to hold 460 by 660 mm bun p
28、ans,which are standard throughout the baking industry.Retail Stores. Stores use reach-ins for many different nonfooditems. Drugstores often have refrigerators with special drawers forstoring biological compounds. (See the section on Nonfood Instal-lations.)Fig. 3 Open and Enclosed Roll-In RacksFig.
29、3 Open and Enclosed Roll-In RacksFig. 4 Roll-In Cabinet Usually Part of a Food-Handling orOther Special-Purpose SystemFig. 4 Roll-In Cabinet, Usually Part of Food-Handling or Other Special-Purpose SystemFood Service and General Commercial Refrigeration Equipment 16.3Retail Florists. Florists use rea
30、ch-in refrigerators for displayingand storing flowers. Although a few floral refrigerator designs areconsidered conventional in the trade, the majority are custom built.The display refrigerator in the sales area at the front of the shop mayinclude a picture window display front and have one or more
31、displayaccess doors, either swinging or sliding. A variety of open refriger-ators may also be used.For the general assortment of flowers in a refrigerator, most re-tail florists have found best results at temperatures from 4.5 to 7C.The refrigeration coil and condensing unit should be selected tomai
32、ntain high relative humidity. Some florists favor a gravity cool-ing coil because the circulating air velocity is low. Others, how-ever, choose forced-air cooling coils, which develop a positive butgentle airflow through the refrigerator. The forced-air coil has anadvantage when in-and-out service i
33、s especially heavy because itprovides quick temperature recovery during these peak condi-tions.Nonfood Installations. Various applications use a wide range ofreach-ins, some standard except for accessory or temperature modi-fications and some completely special. Examples include (1) bio-logical and
34、pharmaceutical cabinets; (2) blood bank refrigerators;(3) low- and ultralow-temperature cabinets for bone, tissue, and red-cell storage; and (4) specially shaped refrigerators to hold columnchromatography and other test apparatus.Blood bank refrigerators for whole blood storage are usuallystandard m
35、odels, ranging in size from under 566 to 1274 L, with thefollowing modifications:Temperature is controlled at 3 to 5C.Special shelves and/or racks are sometimes used.A temperature recorder with a 24 h or 7 day chart is furnished.An audible and/or visual alarm system is supplied to warn ofunsafe bloo
36、d temperature variation.An additional alarm system may be provided to warn of powerfailure.Biological, laboratory, and mortuary refrigerators involve thesame technology as refrigerators for food preservation. Most bio-logical serums and vaccines require refrigeration for proper pres-ervation and to
37、retain highest potency. In hospitals and laboratories,refrigerator temperatures should be 1 to 3.5C. The refrigeratorshould provide low humidity and should not freeze. Storage inmortuary refrigerators is usually short-term, normally 12 to 24 h at1 to 3.5C. Refrigeration is provided by a standard air
38、- or water-cooled condensing unit with a forced-air cooling coil.Items in biological and laboratory refrigerators are kept in spe-cially designed stainless steel drawers sized for convenient storage,labeled for quick and safe identification, and perforated for properair circulation.Mortuary refriger
39、ators are built in various sizes and arrange-ments, the most common being two- and four-cadaver self-containedmodels. The two-cadaver cabinet has two individual storage com-partments, one above the other. The condensing unit compartment isabove and indented into the upper front of the cabinet; also,
40、 ventila-tion grills are on the front and top of this section. The four-cadavercabinet is equivalent to two two-cadaver cabinets set together; thestorage compartments are two cabinets wide by two cabinets high,with the compressor compartment above. Six- and eight-cadavercabinets are built along the
41、same lines. The two-cadaver refrigeratoris approximately 965 mm wide by 2390 mm deep by 1955 mm highand is shipped completely assembled.Each compartment contains a mortuary rack consisting of a car-riage supporting a stainless steel tray. The carriage is telescoping,equipped with roller bearings so
42、that it slides out through the dooropening, and is self-supporting even when extended. The tray isremovable. Some specifications call for a thermometer to bemounted on the exterior front of the cabinet to show the insidetemperature.Refrigeration SystemsReach-in cabinets can be supported by either re
43、mote or self-contained refrigeration systems. The following two types of sys-tems apply to all types of refrigeration equipment.Self-contained systems, in which the condensing unit and con-trols are built into the refrigerator structure, are usually air-cooledand are of two general types. The first
44、type has the condensing unitbeneath the cabinet; in some designs it takes up the entire lower partof the refrigerator, whereas in others it occupies only a corner at onelower end. The second type has the condensing unit on top.Remote refrigeration systems are often used if cabinets are in-stalled in
45、 a hot or otherwise unfavorable location where noise orheat of the condensing units would be objectionable. Other specialcircumstances may also make remote refrigeration desirable.There are tradeoffs associated with locating a self-contained con-densing unit beneath the refrigerator; although air ne
46、ar the floor is gen-erally cooler, and thus beneficial to the condensing unit, it is usuallydirtier. Putting the condensing unit on top of the cabinet allows full useof cabinet space, and, although air passing over the condenser may bewarmer, it is cleaner and less obstructed. Having the condensing
47、unitand evaporator coil in the same location provides a refrigeration unitthat can be removed, serviced, and replaced in the field as a whole. Ser-vicing can then be done at an off-site repair facility.FOOD FREEZERSSome hospitals, schools, commissaries, and other mass-feedingoperations use on-premis
48、es freezing to level work loads and operatekitchens efficiently on normal schedules. Industrial freezing equip-ment is usually too large for these applications, so operators useeither regular frozen food storage cabinets for limited amounts offreezing or special reach-ins that are designed and refri
49、gerated tooperate as batch-type blast freezers.Chapter 29 covers industrial freezing of food products.BLAST CHILLERS AND BLAST FREEZERSThese units are designed to rapidly chill or freeze food immedi-ately after it has been cooked. Blast chillers and freezers are used byfood-service establishments, such as restaurants, hotels, and cafete-rias, that cook large quantities of food items, chill or freeze them,and later reheat portions to be served. Blast chillers are designed toallow operators to comply with food preparation, handling, andstorage guidelines on preventing the gro
