Project Overview
Annual Reports
Commodities
- Animals: goats
- Animal Products: dairy
Practices
- Animal Production: general animal production
- Farm Business Management: budgets/cost and returns, feasibility study, agricultural finance, market study, value added
- Production Systems: agroecosystems
- Soil Management: organic matter
Abstract:
By the recommendations of the project evaluation committee, the shelf-life and food safety parameters of commercial soft goat cheeses produced in Georgia were evaluated during the initial phase of the project. However, implementation of the research had been delayed more than one year due to the problems of employment of the Research Associate. Effects of refrigerated and frozen storage on shelf-life of commercial soft goat milk cheeses were evaluated in relation to microbiological, physico-chemical, and rheological characteristics during the first 2 years. Although some variations were observed between lots of the cheeses, coliforms and E. coli counts were non-detectable, while non-coliforms such as Pseudomonas were present. No Staphylococcus aureus were detected, whereas unidentified presumptive Staphylococcus species may exist. Cohesiveness of the cheeses significantly decreased, while viscoelastic properties remained unchanged as storage progressed. Yeast and mold counts were inversely correlated with cohesiveness.
The 2nd and 3rd phases of the project were focused on the feasibility of freezing and 3 months frozen-storage of goat milk cheeses for later marketing. Impacts of freezing on storage stability and shelf life of commercial plane soft and PI’s university manufactured Monterey Jack semi-hard goat cheeses were evaluated for the changes in organic acid profiles, sensory properties, rheological and microbiological characteristics with reference to fresh control. Freezing did not have significant adverse effects on nutritional, organic acids, sensory properties, and generally reduced microbial counts compared with the nonfrozen control cheeses. No significant adverse effects of 3 months frozen-storage were observed on nutritional and sensory properties of the two cheeses, although there were some changes in organic acids, rheological indices and microbial populations in comparison with the nonfrozen control goat cheeses.
For the final phase of the project, the research was aimed at evaluation of the feasibility of 6 month extended frozen-storage of goat milk cheeses for the year-round consistent marketing. Food qualities of plain soft and Monterey Jack semi-hard goat cheeses by the extended frozen-storage were evaluated for quantitative changes in chemical, organic acids, rheological, microbial and sensory scores as well as fatty acid composition. Although there were some significant changes in organic acid and fatty acid compositions, rheological and microbiological indices in comparison with the nonfrozen control cheeses, six months extended frozen-storage showed minimal impact on nutritional and sensory qualities of the initial cheeses. It was concluded that the frozen-storage would be feasible for later marketing of goat cheeses for sustainable dairy goat production if the processing parameters are tightly controlled.
Project objectives:
After awarding the project funds, the objectives and performance targets of the project were changed somewhat at the initial phase due to the recommendations of the project planning committee through its first committee meeting. This modification of the proposed research for the first year would enable the investigators to gather practical and applicable research data, which would be highly useful for dairy goat farmers (producers) as well as consumers. The changed project activities during the first year were as follows:
1.) Evaluate food quality and shelf-life of the commercial fresh soft goat milk cheeses produced by the Georgia dairy goat farmers,
2.) Compare the same parameters of the frozen-stored soft goat milk cheeses after 3 to 6 months at –20oC with those of the fresh cheeses for off-season marketing.
3.) Determine microbiological, rheological, nutritional and physico-chemical changes in fresh and frozen-stored soft goat cheeses in relation to the shelf-life and storage stability of the products.
For the subsequent phases of the project, more comprehensive studies have been conducted for the evaluation of soft goat cheeses in along with one or two developed hard type goat cheeses under the following objectives:
1.) Develop semi-hard and hard (Monterey Jack and Cheddar-type) goat milk cheeses using the surplus milk during the peak season, and store the cheeses at 4oC and
–20oC for different lengths of time.
2.) Study the effects of freezing and storage on food quality and shelf-life of the experimental soft and hard goat cheeses in rheological, textural, nutritional, microbiological, organic acids and flavor chemical characteristics of the products.
3.) Conduct sensory evaluation and consumer acceptability studies on the soft and
developed hard goat cheeses, and correlate the sensory scores with the results of all proposed parameters investigated under the objective 2.)
4.) Conduct economic analysis and marketing research on the goat cheese products through extensive consumer acceptability studies in order to determine the sustainability and profitability of dairy goat production.