The following patent states that sterilized infant formula has a shelf life of 1 1/2 years. I believe I have also seen 2 years but have no reference for that. One of my posts was written rather poorly and the impression seems to be that I am saying that genetic engineering increases shelf life. I wasn't saying that. The following patent is worth reading. Valerie W. McClain, IBCLC http://www.uspto.gov/patft/index.html patent # 6194009 "Refrigeration-shelf-stable ultra-pasteruized or pasteruized infant formula" inventor: Kamarel assignee: Princeton Nutrition, LLC "An infant formula which contains all the essential macronutrients and micronutrients, have heretofore been available only in shelf-stable sterilized products. Sterilized products are generally sold in hermetically sealed containers such as cans and are intended to have a long room temperature shelf-life. Table 2 lists several commercially available shelf-stable sterilized infant formulas. As will be discussed further herein, sterilization processes, due to the severity of the heat treatment can cause undesirable physical, chemical, enzymatic and microbial changes which deleteriously affect the final product. Moreover, although such sterilized products are often marketed as "ready-to-feed" (RTF), they are typically stored at room temperature, and enzymatic reactions still occur, albeit slower, during room temperature storage of sterilized products. Such reactions can result in a host of undesirable defects, such as the destruction of vitamins which are necessary to the integrity of the overall product. Since sterilized products are designed to have up to one and a half (11/2) year of room temperature shelf-life, such products will have a different actual content of degradable micro nutrients (vitamins) in the early part of its shelf-life as compared to the latter part. Thus, an infant will obtain a different and unknown amount of vitamins depending on when the sterilized product is consumed. To account for this degradative process during long-term shelf-life, manufacturers of sterilized infant formulas often include up to 50% to 70% more of a given vitamin than would normally be included to account for the inherent degradation loss and to ensure the product is likely to contain at least the labeled amount of nutrients at the end of its shelf-life. Such large overdosing results in an imbalance in the taste of the product, particularly if consumed in the early stages of its shelf-life. Moreover, the cost factor of including such large overdoses is considerable. In addition to the high cost of sterilization, and increased overdosing of vitamins, sterilization processes require high cost packaging, such as in metal cans. Like milk, liquid infant formulas (usually containing milk proteins and sometimes soy protein) are heated for a variety of reasons, the main reasons being: to remove potential pathogenic organisms and to increase shelf-life. The major concerns about the resulting products of thermal process are safety and quality. Like milk, heat-treated infant formulas should not be a public heath risk. They should have a good keeping quality, provide an intended balance of nutrients, and be of desirable sensory characteristics, i.e., appearance, color, flavor, and mouth feel. When milk or infant formulas are heated at a constant temperature, all their constituents and components will be affected, but to different extents. Increasing the temperature will accelerate reaction rates. But different reactions will be affected to different extents. Physical, chemical, enzymatic and microbial changes will depend principally upon the time-temperature conditions, but will also be influenced by other factors, such as composition, pH, and oxygen content. The wide range of reactions taking place when infant formulas are heated will influence the safety and quality of the product. Upon heating of products at higher temperatures for longer times, some undesirable changes can also take place (e.g., decrease in pH, Maillard browning, cooked caramel flavor, denaturation of whey proteins and interaction with casein). The changes that take place during heating and subsequent storage, can affect the nutritional value and sensory characteristics. In thermal processing, the most important parameter is the level of microbial inactivation achieved. For safety reasons, the minimum holding time (residence time) should be considered for microbial inactivation, although this will give an underestimate of the true level of microbial inactivation." *********************************************** To temporarily stop your subscription: set lactnet nomail To start it again: set lactnet mail (or digest) To unsubscribe: unsubscribe lactnet All commands go to [log in to unmask] The LACTNET mailing list is powered by L-Soft's renowned LISTSERV(R) list management software together with L-Soft's LSMTP(TM) mailer for lightning fast mail delivery. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html