WATER 



RAW PRODUCT 



STEAM 



WASHING 



2^ 



GRADING, 

 TRIMMING 



PEELING, yV/ 

 PITTING, ~V/ 

 CUTTING W^ 



mi 



RINSING, 

 PLUMING 



w;^^ 



BLANCHING, 

 CONCENTRA- 

 TING 



SIRUF^ 

 BRINE 



FILLING, 

 SEALING 



'f mm^ \ 



EXHAUSTING, 

 PROCESSING 



COOLING 



SOLID 

 WASTE 



CLEANING, 



WASTE 



PLUMING 



CANNED 

 PRODUCT 



blanch waters are recirculated, but makeup waters 

 must be of potable quality. Steam generation, 

 representing about 15 percent of water intake, 

 when used for blanching or injection into the prod- 

 uct must be produced from potable waters, free of 

 volatile or toxic compounds. Syrup, brine, or water 

 used as a packing medium must be of high quality 

 and free of chlorine. 



After heat processing, the cans or jars are 

 cooled with large volumes of potable water. This 

 water must be chlorinated to prevent spoilage of 

 the canned foods, by microorganisms in case that 

 cooling water is aspirated during formation of a 

 vacuum in the can. 



A final significant use of water is for transport- 

 ing from the cannery, the inedible product, spil- 

 lage, and trimmings that are discarded as waste. 



A flow sheet showing the various uses of water 

 and origin of waste streams is attached as figure 

 V-3. 



Most fruit and vegetable canning, as opposed to 

 canning of specialty products, is highly seasonal. 

 The demand for water may vary 100 fold among 

 months of the year. The water-demand variation 

 may be several fold even for plants that pack sub- 

 stantial quantities of nonseasonal items. 



The gross quantities of water used per ton of 

 product vary widely among products, among can- 

 neries, and among years in the same cannery. The 

 proportion of gross water supplied by recirculation 

 has increased over the years and the trend is ex- 

 pected to continue. A tendency has been noted to 

 use more water per ton of product as the propor- 

 tion of recirculated water increases. The consump- 

 tive use of water is also expected to increase with 

 recirculation. 



The following tabulation gives the fate of gross 

 water intake as based on the 1963 census of 

 manufacturers (7) for canning plants having an 

 annual water intake of 20 or more million gallons. 



Water quantity 

 Item (bgy) 



Intake 48 



Reuse 18 



Consumption 4 



Discharge 44 



Percent of 

 intake quantity 



100 

 37 



LIQUID WASTE 

 Figure V-3 -Uses of water and steam in canning. 



A breakdown of the quantities and percentages 

 of the total water used in the various process oper- 

 ations based on data from the National Canners 

 Association is as follows: 



209 



