Doctoral Dissertations

Date of Award

12-1969

Degree Type

Dissertation

Degree Name

Doctor of Philosophy

Major

Plant, Soil and Environmental Sciences

Major Professor

B.S. Pickett

Committee Members

H.D. Swingle, D.L. Coffey, C.W. Marr, A.D. Rutledge

Abstract

The purpose of this study was to evaluate how four quality factors of southern peas were affected by three methods of harvest and by five storage periods,. The quality factors considered were ascorbic acid, color, texture, and sugar content of shelled peas which had been blanched, frozen, and thawed.

Peas harvested by field combine were windrowed for time periods of less than 1 hour, 3, and 6 hours before combining and then held as shelled peas for periods of less than 1 hour, 6, 12, 18, and 24 hours at a controlled temperature of 88° F. before blanching. Machine harvested pods and hand harvested pods were held at a controlled temperature of 88°F. in burlap bags for holding periods of less than 1 hour, 12, 24, 36, and 48 hours before shelling and blanching. Significant findings are presented below.

Ascorbic AcidThe ascorbic acid quality factor was affected by time held as field combined shelled peas and by time stored in pods after hand and machine harvesting. Generally speaking, deterioration of ascorbic acid quality factor increased as the duration of holding periods increased.

ColorIn field combined peas, the percentage green color was affected by time spent in windrow, time held as shelled peas, and the interaction effects of these holding periods. In general, windrow holding time of 6 hours resulted in significantly higher green color percentages regardless of time held after shelling than did windrow holding times of less than 1 hour or 3 hours. Field combined peas were significantly higher in percentage green color when combined 6 hours after windrowing than were peas hand shelled from hand picked pods.

Texture

A holding period of 3 hours in the windrow before combining resulted in less force required to shear a sample of thawed peas than did a windrow holding period of less than 1 hour. A storage period in the hamper of less than 1 hour as shelled peas resulted in a significantly greater force required to shear a sample of thawed peas than did any of the other holding periods.

Method of harvesting pods did not significantly affect the texture in pods harvested at the 20 percent maturity stage. At the 50 percent stage of maturity, however, peas shelled from hand picked pods required a greater force to shear samples of thawed peas than did peas shelled from pods harvested by machine.

SugarThe sugar content of peas did not differ significantly due to method of harvest. Duration of storage affected the sugar content of peas shelled from pods harvested at the 20 percent mature stage. Pods held for less than 1 hour before shelling contained significantly more total sugar than did peas shelled from pods held 12 hours or longer.

Download
Files over 3MB may be slow to open. For best results, right-click and select "save as..."

Share

COinS