Abstract #M106

# M106
Effect of rinsing and washing time and water temperature on removal of peanut allergen from ice cream processing equipment.
J. Zhang1, Z. Ustunol*1, 1Michigan State University, East Lansing, MI.

Ice-cream is a product which may contain all of the key food allergens, and prevention of cross contamination in a processing facility is a challenge to ice-cream manufacturers. Effective cleaning of the equipment is important to prevent food allergen cross contamination. In this study, we hypothesized that higher water temperature and longer rinsing-, washing-time will result in lower peanut allergen left on stainless steel surface. Ice cream, which contains peanut and soy, was used in this study. Thawed ice cream was filled in a stainless steel pipe for 1.5 h and then rinsed or rinsed and washed in a simulated clean-in-place system. Water pressure was 70 psi, flow rate was 1.53 L/s. Chlorinated alkaline detergent was used for washing. The effect of 3 times (10, 20 and 30 s) and 5 water temperatures (20, 30, 40, 50 and 60°C) on removal of peanut allergen from stainless steel pipe was investigated. Samples were obtained by swabbing, and tested for concentration of peanut allergen protein Ara h 1. All experiments were replicated 3 times. When equipment was only rinsed, concentrations of peanut allergen residue left on the pipe ranged from 207 ppm to 63 ppm. The overall trend suggested that higher water temperature and longer rinsing time resulted in lower peanut allergen concentration on the equipment (P < 0.05). When equipment was rinsed then washed, concentrations of peanut allergen residue ranged from 1.43 ppm to 0.015 ppm. The overall trend suggested that water temperature played an important role in removing peanut allergen (P < 0.05) while time showed a less important effect than temperature on allergen removal in this study. Only rinsing was not effective in removal of all peanut allergen. Rinsing and washing at temperatures 50°C or above, and 20 s or longer are needed to remove all peanut allergen from stainless steeel equipment. Effective cleaning can reduce the chance of cross contamination as well as save time and money for the food industries. Understanding the principle of rinsing and washing is essential for effective allergen removal.

Key Words: peanut allergen, cleaning, processing equipment