The factors responsible for the thermal resistance of microorganisms are the species of the microbial population, food composition, pH, oxygen and water activity of the product. It is not usually worthwhile to use osmotic dehydration for more than 50 percent weight reduction because of the gradual decrease in the rate of osmosis. The high concentration of solute that surrounds the fruits and vegetables also prevents discoloration and leads to better retention of nutrients in the product.
The time it takes to freeze the food depends on the temperature in the freezer compartment. The freezing is achieved by immersion in the liquid, spraying of liquid or circulation of the vapors over the product. When water freezes, it expands, and the ice crystals formed can cause the cell walls of the food to burst.
Chemical Preservation
In addition, the size of the freezer limits the amount of storage space and unwanted texture in some foods. The limitations of the applicability of this technique are due to microbial safety, the health suitability of the product, and the deterioration of physical properties and economics. Drying/Dry Salting Fermentation: In this technique, barrels are filled with alternating layers of vegetables and salt until 3/4 of the container is filled.
According to FDA, 'a chemical preservative is any substance capable of inhibiting, retarding or stopping the process of fermentation, acidification or other decomposition of food or of masking any of the evidence of such a process or of reducing the acid which generated by such a process but does not include salt, sugars, vinegar, spices or oils extracted from spices'. Chemical food preservatives are added in very small amounts (up to 0.2 percent) and they do not change the organoleptic and physico-chemical properties of the food. Chemical food preservatives are applied to food as direct additives during processing, or develop spontaneously during processes such as in fermentation.
In addition to preservation, these compounds contribute to the quality and identity of the products. Mode of action of food additives involves alteration of cell wall permeability, alteration of colloidal nature of protoplasm, damage to the cell wall, damage to proteins, inhibition of enzyme activity, disruption of cytoplasmic membrane, bacteriostatic or bactericidal action (toxicity of the antimicrobial agent towards microorganisms) and interference with synthetic processes. Chemical food preservatives should only be used at a dosage level necessary for normal preservation and not more than prescribed by FPO.
Factors that determine/influence the performance of chemical food preservatives are the chemical composition, pH, concentration, type of microorganisms and the initial number of microorganisms in the treated product. Benzoic acid (as sodium benzoate) and its derivatives have a preservative effect that is stronger against bacteria than against yeasts and molds.
Biological Preservation (Fermentation)
The use of chemical preservatives must be strictly limited to those substances recognized as having no harmful effects on human health and accepted by national and international standards and legislation. Sorbic acid works on molds and certain yeast species which in higher dose levels also works on bacteria and formic acid is more active against yeasts and molds and less on bacteria. ii) Artificial acidification is carried out by adding acetic acid which is stable in specific working conditions. In this case, biological principles of preservation are acido-anabiosis and, to a lesser extent, acido-abiosis. iii)Combined acidification is a preservation technology, which as a preliminary processing step involves a weak milk fermentation followed by acidification (vinegar addition).
Sauerkraut is the product of characteristic sour flavor, obtained by the full fermentation, mainly lactic acid, of properly prepared and shredded cabbage in the presence of 2-3 percent salt. Sauerkraut and pickle products can be preserved under the effect of natural or added acidity, followed by pasteurization when this acidification is not sufficient. Despite the introduction of modern preservation methods, lactic acid fermented vegetables still enjoy great popularity, mainly because of their nutritional and gastronomic properties.
Combined Method of Preservation (Hurdle Technology)
Various methods such as freezing, canning, dehydration, chemical preservation, etc. is commonly used to preserve food. Value added products 1. Fruits and Vegetables.. i) Jam, jelly, marmalade and preserves: Preparation of jam, jelly and marmalade is based on the concentration of fruits to almost 70 percent solids (TSS) by addition of sugar and heat treatment. Jam can be made from a single fruit (apple, strawberry, banana, pineapple etc.) or from a combination of two or more fruits.
A perfect jelly should be transparent, well set but not too hard and should have an original fruity taste. Marmalade is a fruit jelly in which citrus slices or their peels are suspended. The finished product can be stored without hermetically sealing and refrigeration. ii) Chutneys and Sauces: Chutney is a mixture of fruits or vegetables with spices, salt and/or sugar, vinegar etc.
A good chutney is smooth, tasty and pleasant and has the right taste of the fruit or vegetable used to make it. Vinegar, salt, sugar and spices are common preservatives used to preserve these products. Chemical preservatives such as sodium benzoate and potassium metabisulphite used for long-term storage help inhibit the growth of microorganisms without affecting other physicochemical and sensory properties of the product.
Some factors considered when choosing a chemical to use as a preservative include the type of organism to be monitored, the pH of the product, the duration and conditions of the product's storage, and the physical and chemical characteristics of the food. iii) Fruit Juices/Drinks: Fruit juices are stored in various forms such as pure juices and drinks. These beverages can be distinguished based on the differences in total soluble solids (TSS) content and minimum juice percentage, as shown in Table 2.
Pasteurization: Preservation by heat is the most common method. It may be done in three ways
Fermented beverages: Fruit juices that have undergone alcoholic fermentation with yeast and lactic acid fermentation with bacteria.
- Mushrooms
- Coconut
- Floricultural Crops
- Spices
- Horticultural waste utilization
The actual composition of the oleoresin depends on the spice chosen for extraction, its maturity, post-harvest handling and, most importantly, the solvent and conditions chosen for extraction. The volatile components of the spice, known as essential oil, which are also part of the oleoresin, are obtained directly from the raw material by steam distillation. The composition of essential oils depends on the selection of the spice, its quality and the applied distillation technique.
Waste from the papaya and pineapple industry is used to produce the enzymes papain and bromelain respectively. The ideal packaging can be compared to that of banana, orange peel and coconut shell – the packaging provided by Mother Nature. In modern times, packaging has been identified as an integral part of processing in the food industry as it protects products from the negative effects of the environment.
Packaging is useful for the safe delivery of the contents from the production centers to the consumption points. Foods are safe indefinitely while frozen, but once food begins to thaw and become warmer than 40 °F (4.4 °C), the bacteria that may have been present before freezing can begin to multiply. Although the center of a package may still be frozen while thawing, the outer layer of the food is in the "Danger Zone".
This includes all aspects related to customer needs such as quality specifications, safety, delivery method or date, price, etc. The desired high quality of the final product is planned and achieved by executing Standard Operating Procedures (SOP) that guarantee desired quality. quality of the intermediate products at each production step that meets the requirements for Good Manufacturing Practices (GMPs). These are the systems that can demonstrate that the organization can meet the specifications and requirements of the customers.
They also allow the management of the organization to know that the customer's requirements are being met.
N Act / Order
Voluntary Standards 1. Agricultur
The main purpose of this program is to protect the health of consumers, to ensure fair trade practices in the food trade and to promote the harmonization of all food standards work carried out by international governmental and non-governmental organizations. Hazard Analysis and Critical Control Point (HACCP): Hazard Analysis and Critical Control Point (pronounced "hasip") is a food safety program developed nearly 30 years ago for NASA to ensure the safety of food intended for use astronauts in the space program. All seven principles must be based on proven scientific research in the relevant field in which the food processing process is involved.
HACCP helps reduce contamination, reduce recall/destruction of products, ensure market protection, ensure preferred supplier status, demonstrate compliance with international standards, transform goods into branded products and enable international acceptance. Value chain – the extent to which successive customers in a marketing channel add value to a product is of particular importance. The decision depends on the number of consumers and the geographic concentration of the market.
Considering the high perishability and limited shelf life of horticultural products, it is essential that they move from the processing center to the consumer in the shortest possible time. Adequate quantities of the right type of horticultural produce from contract farming should be readily available in the locality, as horticultural crops are highly perishable and deteriorate during long-distance transportation. Adequate supply of labor – Ample labor must be available at all times for efficient operation of the plant.
Machinery and Equipment: Different types of equipment are used in the food industry for different unit operations. There are many research organizations that train manpower, help with project preparation and advice in food processing.
