Document YGEg3MKmE77xY3gLmzdy4LEkO

536 CHAPTER 50 J. G. Woodroof and 8. R. Cecil: Nuts: Better kept--better candy (Food Engineering, Vol 23,1961, p. 129). J. G. Woodroof: Peanut and pecan storage (Ice and Re frigeration, VoL 117, No. 3,1949, p. 34). R. C. Wright: Investigations on the Storage of Nuts fUSDA Technical Bulletin No. 770, June, 1941). W. R. Barger, W. T. Pentzer. and C. K. Fisher: Jiyw tem perature storage retains quality of dried fruit (Food Industry Vol. 20, No. 3, March 1948, p. 337). W. G. Burton: Mashed potato powder. IV Deterioration due to oxidative changes (Journal of the Society of Chemical Industries VoL 68, May 1949, p. 149). L. B. Howard and H. Campbell: Dchydrofreezing--new way of preserving food (Food Industry, VoL 18, No. 5, May 1946, p. R. R. mussen: t, C. E. Hendelj W. P. Talburt, and L. B. Hasdisappearance m dehydrated vegetables during i roi ouiae And Data Book Jtoj8 (hulustrial and Engineering Chemistry, VoL 41, Jujy --r.. '--k. IucsomL W. P. Talburt, A. M. Mylne, and L. A Rrv0 Brommg ol dehydrated vegetables during storage (/irfwbSj and^Engmeenng Chemistry, VoL 39, No. 11, October 1947^ M. P. Masure, G. 8. Bohart, E. J. Eastmcnd, and M M go dVraaltueedocfasrtraortcsh(cPooaodtingfeinchth^eyp,resVeorLva3ti,onNoof. otuaMlitavrcb ls^ _ E- R^ Stadtnmn, H. A. Barker, V. Haas, E. M. Mrak. and G. Mackinney: Storage of dried fruit--Gas changes durine age of dried apricots and influence of oxygen on rate of deterinnL tion^Jndustrial and Engineering Chemistry Vol. 38, March 194^ A. L Morgan, Jr., L. P. Ginnette, J. M. Randall, and J M Graham: Technique for improving instants (Food Enameen VoL 31, No. 9,1959, p. 86). * CHAPTER 51 DISEASES AND DETERIORATION OF PRODUCTS Hcrordi of Spoilage Before and During Storage; Recognition and Control of Diseases; Handling, Temperature, and Humidity Requirements for Maintaining Quality RUITS and vegetables often carry fungus spores and bac Follow cultural practices that promote regular bearing, and Fteria on their surfaces at harvest. Under certain tempera stabilize moisture. Store fruit of proper maturity and cool promptly to 32 F. Maintain humidity nigh enough to prevent ture and moisture conditions these organisms may cause moisture kiss. disease. The extent to which decay is initiated or to which incipient infection develops into active decay in storage de Blue Mold Rot (Penicitin/jn) pends largely on the condition of the commodity, the rate of 'cooling, and the period of holding. Proper temperature and moisture during storage slow aging or ripening and minimise decay, both by keeping the product vigorous and by slowing the rate of development of the organism. Many fungi, how ever, even under optimum conditions for the product, can slowly develop and cause decay during a long storage period. In addition to diseases caused by fungi and bacteria, there Spots of various sizes with decayed tissue that is soft, watery, and can be readily scooped out of the surrounding healthy flesh. Rot usually as deep as wide. Advanced stages have white tufts of of mold which turn bluish-green as spores are produced under moist conditions. Affected tissue has moldy or musty flavor and odor. Most important storage decay of apples. Control: Handle carefully to prevent skin breaks. Cool promptly to 32 F. Keep picking boxes, packing house, and storage room sanitary. White wash walla and ceiling. are many diseases which are not caused by pathogens but are Brown Core due to physiological disturbances. These include diseases such as apple scald, Jonathan spot of apples, and mahogany brown ing in potatoes. Many of these disorders are closely related to temperature conditions. Some are induced by slow rate of cooling; others are brought on by temperatures that are too low, yet not freezing. The quality of each lot of produce should be determined at ti me of storage and regular inspections should be made during No external symptoms. First appears as slight browning or discoloration of core tissue between the seed cavities. Later a or all, of the flesh between the seed cavities and the core may become brown. Serious in McIntosh and other sus ceptible varieties stored for long periods at 30 to 32 F. Control.' Pick at proper stage of maturity. Use controlled atmosphere storage at 38 to 40 F. A disorder with similar symptoms has been reported as a result of exposure to excessive concentrations of carbon dioxide. stora ge. Such vigilance will permit early detection of disease so that, if necessary, the affected commodity can be moved out of Bullseye Rot (See lentice/ Rots) storage before serious loss develops. The brief statements concerning fruits and vegetables which follow have been prepared to apprise warehousemen of the hazards of spoilage during storage and to aid in the recognition and control of difleawa. Only the most important diseases are discussed. Detailed information on most of the diseases, indi cated as numbers in superscript following the name of the Cork Strictly an orchard disease that does not develop in storage. Large maww and streaks of firm, dead, brown tissue deep in flesh and around the core. Surface of apple may be bumpy. Areas larger than spongy tissue of bitter pit Control: Follow recom mended cultural practices. Apply borax to soil around trees that produce apples with internal cork. commodity reference, may be obtained by consulting the refer Freezing Injury ences listed at the end of this chapter. The scientific name of the causal organism is given in paren theses following the common name in order to help the reader to identify references to the diseases in scientific literature. APPLES Altemaria Rot Dark brown to black, firm, fairly dry to dry storage decay centeringat wounds, *kin cracks, in core area, or tn ecald patches. One of the blackest of storage decays. Control: Cultural practices fhat produce apples of good finish; prevent skin diseases and "Junes that open way for infection. Ammonia Gas Discoloration . Circular spots centering at lenticels; dull green on unblushed ade and brown to black on blushed side. Injury may disappear hom slightly affected fruits. Control: Ventilate as soon as posable. Examine fruit for injury at various points in room because 80me sections may escape. Bitter PH Numerous small, sunken bruise-like spots, usually on the calyx talf of the fruit. Majaea of brown, spongy tissue occur adjacent to surface pits or may be fouod deeper in the flesh. In storage spongy tissue near surface loses moisture and tends to become hollow. New areas may appear and develop in storage. Control: Watersoaked, rubbery condition of large areas or of entire apple. Vasculare (water-conducting strands) brown. Bruised areas in frozen apples large, with wrinkled gray to light brown surface. Moisture lost rapidly from affected areas. In refrigerator - cars most prevalent on floor, at doorways and bunkers; in storage' room most injury in bottom layer boxes, near coils, or against walls next to freezer storage. Control: Heat car during sub freezing weather. Prevent cold pockets in storage rooms by ade quate air circulation. Handle fruit as little as possible while frozen. Thaw at 40 to 50 F. Move thawed fruit into trade channels promptly; do not allow it to become overripe. Internal Breakdown Mealy breakdown of internal tissue in overripe fruit. Flesh soft. Surface often duller and darker than normal. Hastened by too high storage temperature, freezing, bruising, or presence of watercore which it often follows. Control: Pick before overmature. Cool promptly at temperatures as near 32 F as possible for va rieties that tolerate that temperature. Watch rate of ripening, particularly of fruit with watercore. --- Internal Browning , No abnormal skin appearance. Sometimes appears only around core; the outer fleshy portion of the apple remains normal in appearance. Occasionally only outer flesh is involved; usually, however, when internal browning develops in outer fleshy por tion it is accompanied by browning around the core. Disease de velops uniformly throughout tissue. Occurs in firm, sound- 537 lilt r.s! J; : H ! .* 5 ?; ;? . .1; t