PEACH BRUISING: SUSCEPTIBILITY TO IMPACT, VIBRATION, AND COMPRESSION ABUSE

ABSTRACT As an initial step in a study to develop improved protective packaging for fresh peaches, an investigation was made of the susceptibility of peaches to bruising by impact, vibration, and compression. Bruising was studied on five cultivars of peaches: *Redhaven', *Jefferson', *SunPrince', 'Rio-Oso-Gem', and 'O'Henry'. For each cultivar, bruising susceptibility as a function of maturity was studied. Impact bruises were produced by dropping peaches onto a flat steel plate from heights in the range of 31 to 91 cm. Vibration bruises were produced with a transportation simulator vibrating at 6 Hz. Compression bruises were produced with loads of up to 225 N. Susceptibility to impact bruising was independent of state of maturity and dependent on cultivar. Impacts from drops of 31 cm are often sufficient to cause bruising. The study also found that susceptibility to vibration bruising and compression bruising was a ftmction of state of maturity. Vibration and compression bruising data were not sufficient to distinguish among cultivars. Vibration at 6 Hz for 5 min with 1 G maximum acceleration produced significant bruising. Compression loads as low as 44 N applied for 1 min produced significant bruising. The results imply that packaging improvements to diminish vibration bruising are needed