Effect of Surface Properties on Colloid Retention on Natural and Surrogate Produce Surfaces.
Bacterial contamination of fresh produce is a growing concern in food industry. Pathogenic bacteria can attach to and colonize the surfaces of fresh produce and cause disease outbreaks among consumers. Surface properties of both bacteria and produce affect bacterial contamination; however, the effects of produce roughness, topography, and hydrophobicity on bacterial retention are still poorly understood. In this work, we used spherical polystyrene colloids as bacterial surrogates to investigate colloid retention on and removal (by rinsing) from fresh produce surfaces including tomato, orange, apple, lettuce, spinach, and cantaloupe, and from surrogate produce surface Sharklet (a micro-patterned polymer). All investigated surfaces were characterized in terms of surface roughness and hydrophobicity (including contact angle and water retention area measurements). The results showed that there was no single parameter that dominated colloid retention on fresh produce, yet strong connection was found between colloid retention and water retention and distribution on all the surfaces investigated except apple. Rinsing was generally not efficient in removing colloids from produce surfaces, which suggests the need to modify current cleaning procedures and to develop novel contamination prevention strategies. This work offers a physicochemical approach to a food safety problem and improves understanding of mechanisms leading to produce contamination.
Dept. of Plant and Soil Sciences, Univ. of Delaware, 221 Academy Street, Newark, De, 19716, U.S.A.
Volha
V
Lazouskaya
Dept. of Plant and Soil Sciences, Univ. of Delaware, 221 Academy Street, Newark, De, 19716, U.S.A.
Taozhu
T
Sun
Dept. of Civil Engineering, Hefei Univ. of Technology, 193 Tunxi Road, Hefei, 230009, China.
Li
L
Liu
Dept. of Soil and Water Sciences, China Agricultural Univ, 2 Yuanmingyuan West Road, Beijing, 100193, China.
Gang
G
Wang
Dept. of Plant and Soil Sciences, Univ. of Delaware, 221 Academy Street, Newark, De, 19716, U.S.A.
Yan
Y
Jin
D055598:Chemical Phenomena; D032084:Citrus sinensis / Q000737:chemistry / Q000382:microbiology; D003102:Colloids / Q000737:chemistry*; D018556:Crops, Agricultural / Q000737:chemistry* / Q000382:microbiology; D028463:Cucumis melo / Q000737:chemistry / Q000382:microbiology; D005506:Food Contamination; D005516:Food Microbiology; D005519:Food Preservation / Q000379:methods; D005638:Fruit / Q000737:chemistry / Q000382:microbiology; D057927:Hydrophobic and Hydrophilic Interactions; D018545:Lactuca / Q000737:chemistry / Q000382:microbiology; D018551:Solanum lycopersicum / Q000737:chemistry / Q000382:microbiology; D027845:Malus / Q000737:chemistry / Q000382:microbiology; D008962:Models, Theoretical; D011137:Polystyrenes / Q000737:chemistry; D018724:Spinacia oleracea / Q000737:chemistry / Q000382:microbiology; D013499:Surface Properties; D014675:Vegetables / Q000737:chemistry / Q000382:microbiology
D003102:Colloids; D011137:Polystyrenes
colloids; food safety; fruits and vegetables; image processing; physicochemical properties