Food Science 103 Virtual Lab Hand Crafted Sausages Summary of the Activity In the traditional lab students worked in teams to process a variety of sausages using a hand cranked linker press Once all the sausages were linked the class then weighed the product cooked and or smoked the sausages cooled and weighed the product again to help calculate the product yield Learning objective The learning objectives of this lab are to Understand the scientific principle related to processing cured meats Understand the concept of production yield loss and calculate yield loss from the sausage making process Background Since the dawn of man meat has been a part of the human diet Nowadays large debate has evolved around the consumption of meat namely of red meat and its impact on health e g the incidence of colon cancer In respect to food processing meat curing and smoking are some of the major process s meat undergoes Meat curing is the application of sodium chloride sodium nitrite and or sodium nitrate seasonings and other additives phosphates reducing agents etc to meat to develop unique properties and avoid rapid deterioration Overall this process is aimed at both preserving the color of meat and minimizing bacterial spoilage The color of meat is one of the most important factors affecting the consumer s decision to purchase fresh and processed meat products Most of the color of meat arises from Myoglobin which is a protein abundant in muscle tissues Myoglobin doesn t circulate in the blood but is fixed in tissue cells and in its native form has a purplish color When it is mixed with oxygen it becomes oxymyoglobin and produces a bright red color Some of the color of meat also arises from hemoglobin present in the blood or small amounts of blood left in the tissues after slaughter The color of meat may change during processing shipping and storage When safely stored in the refrigerator or freezer color changes are normal for fresh meat and poultry However color changes for processed meat are undesirable mainly because that makes the products less appealing to the consumer For this reason many meat products undergo a curing process in which salts are added to the meat in order to help maintain its color as well as help preserve the food for extended periods of time The basic reaction occurring during the development of the characteristic color of cured meats is represented by Reduced Nitric Oxide Myoglobin purplish red heat Nitric Oxide Myoglobin red Nitrosyl Hemochrome pink Nitrite has an inhibitory effect on C botulinum and produces the cured meat pigment nitric oxide myoglobin However the curing of meats is problematic due to the known impact of nitrites on human health namely cardiovascular health Therefore the addition of nitrites is monitored and regulated by health authorities The addition of salt inhibits spoilage largely by reducing the amount of water available for microbial growth It also improves protein solubilization and the development of flavor Sometimes alkali salts are added to tenderize the meat through solubilization and hydrolysis of the extracellular protein matrix in the tissue Sugar is added to improve flavor phosphates to increase the water binding capacity of meat and several reductants 1 P a g e Food Science 103 to accelerate color development Although smoking provides a preservative effect the main reasons for smoking meat today are the development of specific flavors and improvement of appearance of the final product More than 200 compounds have been identified in wood smoke aldehydes ketones alcohols phenols organic acids etc Most of these compounds exhibit either bacteriostatic or bactericidal properties however formaldehyde probably accounts for most of the preservative action of smoke Traditional Procedure Group Assignments Each group will be responsible for preparing one sausage type Through this process students will need to convert your recipe into a gram weight formula The group assignments will be posted in the pilot plant When converting your household measures into gram weights make sure that you tare your scale use a weigh boat and report the value from an average of at least 5 weights Recipe 1 Bavarian Bratwurst Recipe 2 Smoked Cheddar and Jalape o Sausage Recipe 3 Italian Sausage Sausage making Below outlines the general processing steps used for traditional sausage making Since this will be a lab demonstration many of these steps will be done manually 1 Meat grinding this lab will not focus on grinding and we ll be using ground pork 2 Meat seasoning we will produce three types of seasonings for the sausages refer to Table 1 a Seasoning mix 1 Bavarian Bratwurst b Seasoning mix 2 Smoked Cheddar and Jalapeno Sausage c Seasoning mix 3 Italian Sausage Source weigh record and mix the seasoning blend manually hand mix until well mixed Add the meat and continue hand mix until well blended 3 Stuffing We will be using 5 hand stuffers and natural hog casings NOTE The stuffers have a holding capacity of 5 pounds therefore you will need to reload the unit several times to link the entire product a Prepare casings hog casings should be soaked in water for at least an hour prior to use b Fill canister use the meat mixture to tightly fill the canister c Mount casing on the outlet tube Don t forget to spray PAM on the tube and leave about an inch of casing free d Stuffing carefully press some meat into the casing then release trapped air and tie the casing end Continue to stuff the casing with meat mixture until either casing runs out or canister is empty of meat Tie another knot at the second end of the casing e Carefully twist the stuffed casing into individual sausages 4 Cook a Yield In a bowl report its weight and weigh the amount of finished product you were b Finished linked products should be stored in the refrigerator 38 F until all groups able to link have completed linking 2 P a g e Food Science 103 c When directed all sausage links will be transferred into the smoke house d Due to the limitations of the lab time the product will be cooked outside of lab and chilled in the refrigerator The T A will weigh the chilled sausages and report this weight for post lab completion This product will be stored in the freezer for shelf life extension 5 Storage If refrigerated 38 F sausages should be consumed within 2 3 days If frozen sausages can be safely consumed within 2 3 months Table 1 Seasoning Mix and Meat Blending Recipes Recipe 1 Bavarian Bratwurst 136