Improvement of the safety of food handling practices on small farms

We have completed data collection of produce samples from farmers markets located in different parts of South Carolina. Overall, farmers’ market samples carried over 5 log population of total aerobic bacteria and 4 logs of Enterbacteriaceae. 11 different products were sampled in 7 different county farmers markets and fruits generally had lower bacterial populations than vegetables. Variables having an effect on bacterial counts included the region of the market (Coastal vs. Upstate), type (fruit vs. vegetable), growth location (ground level, under ground, tree/bush) and whether the product was from a climacteric or not.

Produce purchased from Farmer’s Markets located in the coastal region of the state had higher Enterbacteriaceae populations than produce purchased on the Upstate while total aerobic counts varied depending on methodology (whether petri film or plate count agar was used) (Table 1). Vegetable products had higher bacterial populations than fruit products, which is likely related to the growth location (ground level, below ground, above ground) since more fruits grow in trees and bushes than vegetables, many of which grow at or below ground level. The relative bacterial population of produce due to growth locations was: below ground>at ground level>above ground level. Finally, non-climacteric produce had greater Enerbacteriaceae populations than climacteric products but did not differ in total aerobic bacterial populations.
Sampling of a peach processing facility found high bacterial levels on workers hands that were harvesting peaches however these bacterial levels and type (Staphylococcus predominantly) were not found on peaches at the end of the process. Containers used to transport peaches to the processing line were found to have low bacterial levels (< 2 logs per 4 x 4cm swab) after washing but higher populations (~4 logs per 4 x 4 cm swab). Based on the bacterial measurements taken throughout the process, human handling at harvest contributed to the greatest contamination of peaches however the cleaning and sanitizing steps after harvest appeared adequate to remove reduce bacteria to a safe level. Members of the SARE project team have given presentations at four GAPs training workshops in cooperation with the SC Department of Agriculture. A survey was conducted to identify current farming practices, educational needs, and preferred method of educational information distribution to local produce farmers in the Southeast (IRB2010-324). Surveys were distributed during workshops on Good Agricultural Practices (GAPs). Thirty-one surveys from 31 different farms were completed and returned. Most of the farmers (71%) who participated in this survey reported that they use conventional farming practices and most distribute their produce at farmers markets, retail sales or wholesale. Farmers reported that the most popular method of advertising for sale of produce was through ‘word of mouth’ (84%), followed by advertisement on the internet (58%) or printed newspaper (48%). When the farmers were asked to identify the most important challenges that affected their long term success, ‘weeds’ were selected by 77% of the farmers, followed by rainfall/moisture or labor (both at 74%) and soil nutrients (68%). GAPs certification was reported as a challenge by only 13% of the farmers. Sixty-eight percent of the farmers reported that they were ‘not sure’ if they needed additional educational training on farming practices from the local University; however, they (68%) were interested in receiving information on organic agriculture.
Another survey was conducted to determine consumer perceptions and purchasing decisions of fresh produce (IRB2010-324). Four-hundred and eight consumers were surveyed in the Southeast at local grocery stores. Seventy-two percent of the survey respondents were female, and most of those completing the survey were 18-29 years of age (27%), 60-69 years of age (20%), or 50-59 years of age (15%). Sixty-one percent of the respondent indicated that they purchase fresh produce on a weekly-basis, while another 15% reported purchasing fresh produce on a monthly basis. More than one-third of the consumers who were surveyed did not know about the “certified” state marketing programs through the State’s Department of Agriculture (for example “certified SC grown” through the SC Department of Agriculture). Sixty-two percent of the respondents indicated that they purchased organic produce. Eighty-five percent of these respondents who reported purchasing organic produce indicated they would choose locally-grown produce over organic produce. The respondents that reported that they ‘never eat organic produce’ were asked to rank the reasons for this decision, and the ranking was as follows:
Too Expensive > Not Convinced of the Benefits = Not Always Sure If It Is Labeled Properly > Lack of Information > Not Available Where I Shop
These data demonstrate that cost remains the most important reason for consumers who do not purchase organic produce. Data also shows that consumers who purchase organic would rather buy local produce.
A study was conducted to evaluate the chemical composition and quality attributes of certified organic and conventional fresh collard greens (Vates variety) grown in the controlled environment of a greenhouse. Previous research has suggested that organic produce may be higher in certain nutrients than their conventional counterparts. One of the suggested nutrients to be influenced by production practices are polyamines; however, there is limited evidence to support this claim. Amines such as diamines (putrescine and cadaverine) and polyamines (spermine and spermidine) are important in the regulation of nucleic acid function, protein synthesis and the stabilization of membranes. They can be found in certain foods, including fruits and vegetables. In this study, USDA organic and conventional collard greens were grown in a controlled environment to examine the effect of cultivations practices on level of polyamines in the leaf-tissue and to determine influence of cultivation on other collard quality attributes. Organic collard-plants weighed less than their conventional counterparts (at maturity of 75 days after planting, or extended growth of 91 days after planting) and were lighter in color than conventional collards (P < 0.05). When collards were grown during the summer months, organic collards contained higher levels of spermidine (18.0 nmol/g) as compared to the level of spermidine found in conventional collards (6.8 nmol/g). Polyamines were found to be associated with higher yellow color values (+b scores) on the leaves of organically grown collards- a factor that may be used as a rapid method for predicting higher levels of polyamines in collard greens.

• Bacterial populations recovered from produce purchased at farmers markets in SC.