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Coffee grown in the United States, primarily from the state of Hawai’i, represents less than 1% of the world’s supply. Kona coffee, grown on the western side of the island of Hawai’i, is the most recognized and highest valued Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 9-13% moisture within 4 to 6 days. Reducing water activity (aw) below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, and evaluate factors affecting the drying time of sun-dried Kona coffee. Ten Kona region farms were visited in the fall of 2017 to measure the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions during drying. Daily measurements of coffee moisture level, water activity, bean layer depth and coffee temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (31.6 ± 4.3%), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time.

Salmonella and Cronobacter sakazakii are two leading causes of foodborne illness associated with low-moisture foods, including infant formula. Both causative organisms can persist in food manufacturing processing environments and contaminate finished product if programs are not in place to limit their introduction and control their spread. An environmental sampling and monitoring program is an important tool that food manufacturers use to determine the effectiveness of their sanitation practices and pathogen control efforts. Guidance for initiating an environmental sampling plan and evaluating the plan is lacking. The objective of this study was to develop microbiological environmental sampling plans based on the answers to a series of questions related to product hazards, processing risks and controls, and knowledge of appropriate microbiological sampling and testing protocols. Furthermore, these initial sampling plans were related to the volume of product and size of the processing facility. An interactive spreadsheet tool for designing sampling monitoring plans for an infant formula process was developed using Microsoft Excel. Additionally, the tool can be used to record qualitative and quantitative sample test results, and to alert the user how the upcoming sampling plan will be changed, if necessary, based on monthly test summaries. The sampling tool provides a simple method for selecting an appropriate environmental sampling plan (samples per zone per month) and provides a rationale and guidance for creating and modifying these plans. Effective sampling plans and trend analysis of sample test results support the food processors decisions for implementing controls to enhance food safety. Master of Science in Life Sciences