Research Accomplishment Reports 2010

Syneresis Sensor Technology Development for Curd Moisture Content Control. Renewal Application

F.A. Payne, M. Castillo, C.L. Hicks
Department of Biosystems and Agricultural Engineering

 

Non-Technical Summary

The cheese making industry is a very important segment of the US agriculture (~30% of world cheese production). The extent of syneresis controls the moisture, mineral and lactose content of the curd which affects final cheese sensory attributes. Curd moisture control would improve cheeses consistency and quality. Unfortunately, there are currently no technologies available for monitoring curd syneresis.

The goal of this project was to develop an optical sensor technology to monitor syneresis and control the curd moisture content. We have developed an optical sensor technology (during this project) that is able to monitor both milk coagulation and curd syneresis in a stirred cheese vat. The technology consists of a unique optical sensor, a specific light waveband which yields the kinetics of syneresis and regression models which predict cutting time, whey fat losses, cheese yield and curd moisture content as a function of time.

This technology offers the potential for monitoring coagulation and syneresis using a single sensor, which would result in improved cheese manufacture process control, improved cheese quality, and reduced processing losses.

Project Description

The overall objective of this research project is validation of the ability of the developed syneresis sensor technology to control moisture content in cheese production.

DEGREE OF ACCOMPLISHMENT FOR SPECIFIC GOALS.

Objective #1. Evaluate the performance of the syneresis sensor technology under different processing conditions. Fully accomplished. A five-factor, fully randomized, fractional, factorial central composite design (CCD) was employed. The five factors selected as independent variables were coagulation temperature, milk pH, fat to protein ratio, calcium chloride, and cutting time. Three entire replications of this experiment were conducted. Two were used as calibration set while one was used as validation set. During the syneresis phase of cheese making, curd was removed at differing times post-cutting from the cheese-vat. A curd aliquot was used to measure curd moisture content and the remaining one was pressed (0.1 kg cm-2 of pressure during 3 h) for determination of pressed cheese moisture content.

Objective #2. Reduce the standard error of prediction for curd moisture content during syneresis with improvements in the sensor, optical parameters, and moisture prediction algorithms. Currently in progress.

Objective #3. Determine the precision of moisture content control through validation testing. Currently in progress. Accomplishment of objectives 2 and 3 relays in detailed analysis of data obtained for objective #1. Part of the results obtained after data analysis will constitute the Master's thesis for a graduate student involved in the project (Tatiana Gravena Ferreira).

DISSEMINATION OF RESULTS.

Wide dissemination of results has been obtained through publication of results in peer-reviewed scientific journals of high standard, oral presentations and posters at international conference meetings (ADSA, IFT, ASABE, ICEF, IDF, CIHEAM, CIGR, ICDST, EFFOsT) and a lot of different local (Kentucky) and national conferences (Ireland, Spain and USA). Several invited conferences/seminar has been delivered to difference audiences at the IDF, ADSA, University of Tennessee, Cal Poly, University of Murcia (Spain), University College Dublin (Ireland) and Moorepark Food Research Centre (Teagasc, Ireland). Technical consulting has been provided to University of Murcia (Spain), University College Dublin (Ireland), Moorepark Food Research Centre (Teagasc, Ireland), and Central Quesera Montesinos (Spain).

PATENTS.

Syneresis sensor technology for curd moisture content control in cheese making. Authors: Payne, F. A., Castillo, M., Everard, C. D., Fagan, C. C., O'Donnell, C. P., O'Callaghan, D. J. Application #US2008268110-A1. A method for monitoring the syneresis reaction in cheese making using computer vision and color measurement. Authors: Castillo, M., Payne, F. A., Fagan, C. C., Everard, C. D., O'Donnell, C. P., O'Callaghan, D. J. Application #US2008270063-A1.

Impact

A novel optical sensor technology that is able to monitor both milk coagulation and curd syneresis in a stirred cheese vat is being validated (note that curd moisture control requires control of milk coagulation, cutting time and syneresis). The new syneresis technology consists of a unique large field of view optical sensor that provides the information about gel assembly and curd shrinkage kinetics required for curd moisture control. Curd moisture as a function of processing time can be predicted with a SEP of 1.72% over the range of 50 to 90% curd moisture content. Thus, this technology could be used for manufacturing of low, medium and high moisture cheeses.

From an applicative point of view this technology would provide more consistent and efficiency production capability. The technology also would save energy by avoiding unnecessary syneresis processing and allow cheese maker to shift curd size as milk solids change during the year. Further, real time action would be possible in order to obtain the desired curd moisture content if culture inhibition occurs due to bacteriophage or agglutination problems. This technology is considered to offer the potential for a comprehensive process control of cheese making in the vat and for predicting curd moisture.

Several cheese making facilities (Brewster Cheese Inc., and Kraft Foods Inc.) and a food processing engineering firm (ESEInc.) have expressed an interest in testing the implementation of this technology for cheese manufacture.

Publications

Everard, C., OCallaghan, D. J., Castillo, M., Payne, F. A., ODonnell, C. P. 2010. Effects of milk composition, curd draining time and pressing duration on cheese curd moisture and yield. Journal of Dairy Science. Submitted.