Location: Cotton Ginning ResearchTitle: Current procedures for finding moisture content in seed cotton, lint, and cottonseed
|Hardin Iv, Robert|
|Delhom, Christopher - Chris|
Submitted to: ASABE Annual International Meeting
Publication Type: Proceedings
Publication Acceptance Date: 7/30/2018
Publication Date: 7/30/2018
Citation: Funk, P.A., Terrazas, A.A., Yeater, K.M., Hardin IV, R.G., Armijo, C.B., Whitelock, D.P., Pelletier, M.G., Wanjura, J.D., Holt, G.A., Delhom, C.D. 2018. Current procedures for finding moisture content in seed cotton, lint, and cottonseed. ASABE Annual International Meeting, 07/29/2018-08/01/2018, Detroit, MI. Paper No. 1801764.
Interpretive Summary: To address potential differences in results caused by the divergent evolution of procedures practiced by different ARS labs the moisture content of uniform materials were found by following current practices and their antecedent, published nearly 50 years ago. Comparing techniques revealed differences in absolute value but not accuracy, which has improved since 1972. Knowing the difference in results between procedures facilitates fair comparisons. Knowing the uncertainty associated with each procedure allows scientists to design experiments with a statistically adequate number of replications while avoiding costly oversampling.
Technical Abstract: Cotton post-harvest processing research frequently requires moisture content determination for seed cotton, cottonseed, and cotton lint. Standard procedures documented in 1972 and those currently practiced were analyzed to estimate measurement uncertainty. Seed cotton from four modern cultivars (9.4 to 36.8% foreign matter), lint cotton, and cottonseed were stored for more than 30 days in a controlled environment (21 C, 65% RH) and thoroughly blended to reach uniform moisture content. Drying baskets (652 cc) were loaded, in random order, with 25, 35, 50, 71 and 100 g seed cotton or 10, 14, 20, 28 and 40 g lint; cottonseed was placed in 45 cc aluminum cups (10 g) or 800 cc aluminum baskets (50 g). Wet weights were determined in the controlled environment. Additionally, 150 seed cotton samples were placed in plastic zipper bags and sent by air freight to a distant location and back or stored on-site. Replicated sets of seed cotton, lint, and cottonseed samples were weighed inside a drying oven, then outside of it while still hot. Some samples were dried for twice the recommended time. Sample location in the ovens was tracked. Weighing hot dry seed cotton samples outside of the drying oven increased apparent moisture content approximately half of one percent due to buoyancy; weighing lint samples outside the oven increased apparent moisture content by one percent. Smaller differences in apparent seed cotton moisture content were found when halving or doubling the amount of material in drying baskets or doubling the drying time. Foreign matter had a minor influence on apparent moisture content. Storage for three days and shipping by airfreight in plastic zipper bags did not measurably change the apparent moisture content of seed cotton. Sample location within the drying oven made no difference. Measurement uncertainty has decreased compared to 50 years ago, but to increase statistical power the recommended minimum number of samples per treatment has increased slightly.