Effect of Relative Humidity, Storage Days and Packaging on Pecan Kernel Texture: Analyses and Modeling

The studies expounding effects of storage conditions on texture changes is limited. The researchers have been proposing methods to measure pecan texture instrumentally. But current protocols and/or attribute fail to address huge variability during experimentation. Additionally, there are no predictive model to estimate changes in pecan texture during storage. This study addresses all the above concerns and investigate effects of different relative humidity (RH, 30 to 90%) and packaging material (PE, PP, LDPE and metallic laminates or ML) on pecan texture, introducing a rift ratio (F/H or fracturability to hardness ratio) to address variability in the data and predictive model to estimate changes in textural attribute of pecans during storage. The textural analysis was conducted on pecans cores and intact pecans to measure area under curve, fracturability, hardness, cohesiveness, chewiness, springiness, and rift ratio. It was observed that values for rift ratio obtained using intact pecan method had high R 2 (0.72) as compared to rest of textural attribute. A 3-parameter logistic model was employed to predict pecan texture during strage.. The pecans stored at 75%, 80% and 90% lost half of initial fracturability at approx. 115, 3, and 0.15 days (~ 4 hours), respectively. The pecans stored in LDPE, PP and PE packs at 80% lost half of initial fracturability at approx. 26, 57, and 78 days, respectively. The presence of any kind of package delayed the fracturability loss by at least 8 folds at 80% RH. The pecans stored in ML did not experience significant change in textural attributes.