STERILIZATION OF FOOD IN RETORT POUCHES
Innovaster Direct Steam Retort will be used to process rigid containers such as cans. retort chamber should be saturated at the beginning for air is considered an insulating medium and all air will be evacuated from the retort by flooding the vessel with steam and allowing the air to escape through vent valves. There is no overpressure during the sterilization phases of this process,and air-overpressure will be applied during the cooling steps to prevent container deformation.
STERILIZATION OF FOOD IN RETORT POUCHES
Rotary retorts are used to process the food contents in order to accelerate the heat transfer inside the container, with a movement of food inside to provides even better product quality and process efficiency.The baskets or stacks of trays are clamped individually to ensure that the load is well supported with no damage to the containers or baskets and trays. The clamping mechanisms as well as other moving parts like rotor shaft or supporting rollers (trunnions) are designed for heavy duty and long life.
Pilot retorts are the best option for R&D purposes with small output,especially new foods and new packs in formulating scheduled process of new products, simulating sterilization environment in real production, measuring F0 value for mass production etc.Sometimes, our customers use the pilot retorts for the improvement of existing recipes or renewed product formulations to produce small quantities for market testing their new launches.Our Pilot retort capabilities include saturated steam, steam-air, water spray, water cascade and water immersion, rotary end-over-end.
Loaders and unloaders can be fully automated systems for high-speed requirements with integration of all hardware designed for transportation of baskets from loader station to sterilization retorts and from there on to an unload station and packaging area. The global handling system can be monitored by a basket/pallet tracking system.
Retort packaging is a unique form of stand up pouch used for cook-in-a-bag meals and sides, such as soups, rice, sauces, and pasta dishes. The food-grade materials used to construct this type of packaging undergo a sterilization process that extends the shelf life of the product inside while boosting the durability of the package itself. After going through a retort machine, the food and package are able to withstand temperatures up to 250 degrees (121 Celsius), making this the perfect solution for microwavable meals.
Retortable flexible containers are laminate structures that are thermally processed like a can. The materials of the flexible containers provide superior barrier properties for a long shelf life, seal integrity, toughness, and puncture resistance and also withstand the rigors of thermal processing. Generally, any product currently packaged in cans or glass can be packaged in flexible containers. The retort pouch is perhaps the most significant advance in food packaging since the development of the metal can.
A retort pouch or retortable pouch is a type of food packaging made from a laminate of flexible plastic and metal foils. It allows the sterile packaging of a wide variety of food and drink handled by aseptic processing, and is used as an alternative to traditional industrial canning methods. Retort pouches are used in field rations, space food, fish products, camping food, instant noodles, and brands such as Capri-Sun and Tasty Bite.
A retort pouch is constructed from a flexible metal-plastic laminate that is able to withstand the thermal processing used for sterilization. The food is first prepared, either raw or cooked, and then sealed into the retort pouch. The pouch is then heated to 240-250 F (116-121 C) for several minutes under high pressure inside a retort or autoclave machine. The food inside is cooked in a similar way to pressure cooking. This process reliably kills all commonly occurring microorganisms (particularly Clostridium botulinum), preventing it from spoiling. The packaging process is very similar to canning, except that the package itself is flexible. The lamination structure does not allow permeation of gases from outside into the pouch. The retort pouch construction varies from one application to another, as a liquid product needs different barrier properties than a dry product, and similarly an acidic product needs different chemical resistance than a basic product. Some different layers used in retort pouches include:
This multi-layer structure prevents the retort pouch from being recycled into other retort pouches or food packaging. However, the material can be recycled into an aluminized resin or up-cycled into textile materials. The weight of a pouch is less than regular cans or bottles, and the energy required to produce each pouch is less than competing packaging from metals, paper, and glass.
In the consumer market, retort pouches have gained great popularity outside of the United States, particularly in the Pacific Rim region. However, American consumers have evidently demonstrated reluctance regarding the packaging technology, and its adoption has been slow. As a result, many retort packages sold in the United States are packaged in cartons to give them an appearance more familiar to consumers. Tasty Bite products are an example of a retort pouch product packaged in a carton. Several American food distributors have begun manufacturing foods in retort pouches without cartons, notably tuna canning companies Chicken of the Sea, and Bumble Bee. In 2012, the Campbell Soup Company introduced its Go line of ready-to-eat soups in stand-up retort pouches to American consumers.
Thus, we have identified the problem that the commercial food sterilization process has been developed and optimized from a macroscopic point of view. It considers the food as a whole system where the objective function maximizes quality retention (e.g., color, vitamin, and texture) or minimizes processing time, keeping lethality (F0) as a constraint. The exposure of the raw materials to high temperatures for long processing times produces important microstructural changes that increase the loss of nutrients such as nonreducing sugars, amino acids, ascorbic acid, polyunsaturated fatty acids (PUFAs), and carotenoids into the medium, favoring conditions that result in the formation of furans. Therefore, the sterilization of food based on food microstructure changes requires a process that can be controlled according to the changes occurring in the food microstructure. Then, a process performed under variable retort temperature profiles (VRTPs) conditions might be an interesting and better alternative compared to the classic CRTPs process. Variable retort temperature profiles mode is based on the optimal temperature control of the retort, allowing the generation of positive and negative temperature ramps [18,19,20,21,22,23,24,25]. The VRTP has been applied and studied as a tool to improve quality retention, but the paramount factor of the application is related to the reduction in processing time [18,19,21,22,23]. Thus far, no studies have reported that VRTPs and food microstructure evolution through the thermal process.
In general, thermal food sterilization is performed under a CRTP. In a CRT process, the typical temperature used is 121.1 C, and the processing time required to achieve a lethality value F0 (F0 defined as a thermal treatment that allows the reduction of 12 decimal reduction of Clostridium botulinum spores) higher than 3 min will be dependent on the kind of food and the size and shape of the package . F0-values lower than 3 min are synonymous with microbiologically unsafe food. However, maintaining the F0-value as a constraint, it is possible to modify the retort temperature and thus modify the processing time. These different retorts temperature-processing times are known as equivalent lethality processes or isolethal processes .
To determine the suitability of retort processed foods to support long-duration spaceflight, a series of 36-mo accelerated shelf life studies were performed on 13 representative retort pouch products. Combined sensory evaluations, physical properties assessments, and nutritional analyses were employed to determine shelf life endpoints for these foods, which were either observed during the analysis or extrapolated via mathematical projection. Data obtained through analysis of these 13 products were later used to estimate the shelf life values of all retort-processed spaceflight foods. In general, the major determinants of shelf life appear to be the development of off-flavor and off-color in products over time. These changes were assumed to be the result of Maillard and oxidation reactions, which can be initiated or accelerated as a result of the retort process and product formulation. Meat products and other vegetable entrées are projected to maintain their quality the longest, between 2 and 8 y, without refrigeration. Fruit and dessert products (1.5 to 5 y), dairy products (2.5 to 3.25 y), and starches, vegetable, and soup products (1 to 4 y) follow. Aside from considerable losses in B and C vitamin content, nutritional value of most products was maintained throughout shelf life. Fortification of storage-labile vitamins was proposed as a countermeasure to ensure long-term nutritive value of these products. The use of nonthermal sterilization technologies was also recommended, as a means to improve initial quality of these products and extend their shelf life for use in long-duration missions. Data obtained also emphasize the importance of low temperature storage in maintaining product quality.
DNA from hair that has undergone retort pouch sterilization shows considerably more fragmentation. Assessing the extent of DNA fragmentation using a PCR assay could therefore be applied to infer the sterilization history of a contaminated food sample. Such assessments could make it possible to determine whether a food sample had been contaminated by hair during the production process. To determine the extent of retort pouch sterilization, primers specific for the detection of human DNA were designed to give an amplification product of approx 500 bp. Hair was subjected to retort sterilization as a model of contamination, and PCR was performed using the extracted DNA as a template and the primer set for determining retort pouch sterilization. The results showed that no DNA amplification occurred in retort pouch samples, whereas amplification was observed in samples that were unheated, heated in hot water, or heated in a microwave oven. The present method was thus able to specifically detect thermal decomposition of DNA from hair that had undergone retort sterilization, and will be useful for determining whether hair discovered in a retort pouch was responsible for contamination. 041b061a72