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Abstract
Moisture sorption isotherms of alfalfa stems and leaves obtained from the first and third cutting of the season were constructed. Important differences in the relationship between moisture content and water activity values for alfalfa stems and leaves were observed. The extent of those differences was influenced by the initial moisture content and maturity of the alfalfa plant. Water activity, not moisture content, determined the nature of fungal growth on alfalfa stems and leaves. At water activity of 1.0 (moisture content, 51.7 to 65.3%), fungal growth was characterized by extensive mycelial development. Reducing the water activity to .93 (moisture content, 28.1 to 41.7%) dramatically increased fungal fruiting body development and reduced mycelial development. Even though alfalfa stems are nutritionally inferior to alfalfa leaves, fungal fruiting bodies appeared sooner on the stems at water activity values less than .81. Addition of a rich nutrient source, yeast extract, to the stems and leaves did not change that relationship. Analysis of the experimental results reported showed that alfalfa stems have a greater spoilage potential than alfalfa leaves. Implications of these findings to the spoilage process and the nutritional quality of baled alfalfa hay are discussed.
References
- Official method of analysis.12th ed. Assoc. Offic. Anal. Chem., Washington, DC1975
- The effects of moisture and temperature on growth and spore germination in some fungi.J. Stored Prod. Res. 1969; 5: 127
- Water activity, its measurement and significance in biology.Int. Biodeterior. Bull. 1965; 1: 13
- Physiology and biochemistry of fungal sporulation.Ann. Rev. Phytopathol. 1982; 20: 281
- The moisture content of various hays in equilibrium with atmospheres at various relative humidities.J. Am. Soc. Agron. 1947; 39: 697
- A study of hay when exposed to atmospheres with various moisture content.Q. Bull. Mich. Agric. Exp. Stn. 1946; 28: 317
- Self-heating of hay and grain in dewar flasks and the development of farmer's lung antigens.J. Gen. Microbiol. 1965; 41: 389
- Biochemical changes during moulding of self-heated hay in dewar flasks.J. Sci. Food Agric. 1966; 17: 130
- Reducing alfalfa harvest losses. Guide A-318.New Mexico State Univ. Coop. Ext. Serv., Las Cruces1983
- Microbial and biochemical changes during the moulding of hay.J. Gen. Microbiol. 1963; 33: 147
- Pathways of water loss from legumes and grasses cut for conservation.Grass Forage Sci. 1980; 35: 1
- Moisture changes in some agricultural products due to atmospheric conditions.Agric. Eng. 1935; 16: 8
- Effect of temperature and pH on water relations of field and storage fungi.Trans. Br. Mycol. Soc. 1984; 82: 71
- Water and microorganisms in foods – a synthesis.in: Duckworth R.B. Water relations of foods. Academic Press, London, UK1975: 347-361
- Fungi and food spoilage.Academic Press, Orlando, FL1985 (Pages 35–41)
- Influence of water activity on food product quality and stability.Food Technol. 1980; 34: 42
- Water relations of food spoilage microorganisms.Adv. Food Res. 1957; 7: 83
- Interrelations of physical, chemical biological variables in the deterioration of stored grains.in: Sinha R.N. Muir W.E. Grain storage: part of a system. AVI Publ. Co., Westport, CT1973: 15-48
- The germination of mould spores at controlled humidities.Ann. Appl. Biol. 1949; 36: 1
- Mould deterioration of feeding-stuffs in relation to humidity of storage. Part I. The growth of moulds at low humidities.Ann. Appl. Biol. 1944; 31: 102
- Mould deterioration of feeding-stuffs in relation to humidity of storage. Part II. The water uptake of feeding-stuffs at different humidities.Ann. Appl. Biol. 1944; 31: 111
- Water activity and food.Academic Press, London, UK1978 (Page 96)
- The relation between moisture content and molding in cured hay.Ann. Appl. Biol. 1949; 36: 496
- The storage of artificially dried grass.J. Agric. Sci. 1941; 31: 194
- Equilibrium moistures of some hays.Agric. Eng. 1935; 16: 451
Article info
Publication history
Accepted:
April 6,
1989
Received:
December 27,
1988
Identification
Copyright
© 1989 American Dairy Science Association. Published by Elsevier Inc.
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