With this blog, we are going to start with series of three blogs with regard to types of bakery spoilage, the internal factors and the external factors that affects the shelf life of bakery products. The first blog in this series will provide you with an explanation on – What is the shelf life of food and what does it mean? What factors can affect a product's prolonged shelf life and how important is it?
Let’s start with some history
When Antoni van Leeuwenhoek first examined microorganisms in a sample of water, it was in 1674 that man first recorded the existence of microbes. As there is limited information on when the initial awareness of food rotting in relation to microbes was, this discovery was presumably a first step in explaining the deterioration of foods. Anthanasius Kircher may have been the first person to propose that microbes play a part in food spoiling. He analysed decomposing bodies in milk and meat and discovered what he called “worms” that were invisible to the naked eye.
In a hermetically sealed flask, heated beef broth remained undisturbed and free of germs, as noted by Lazzaro Spallanzani in 1765.Henry Pasteur later demonstrated that microbes were to blame for the acidification/souring of milk, and in 1860 he discovered how to utilise heat to kill off pathogenic germs in beer and wine. The first technique consciously modified to extend the shelf life of food products was pasteurisation.
These days, shelf life is such a crucial need that everyone involved in the food chain ought to be interested in. The understanding that a thorough and integrated approach covering the entire food chain, from farm to table, is required to achieve a high standard of food safety and quality is GROWING RAPIDLY. Shelf life is a crucial component of the Food Safety- and Quality department because food manufacturers must balance maintaining food safety/quality and extending shelf life to avoid food waste.However, in the baking sector, such a holistic, integral approach is not particularly popular and is often maintained only by a few reputed Indian Biscuits Brands.
About Shelf Life
Consumers, retailers, and manufacturers all have various perspectives on what is meant by shelf life. The shelf life of a food product is defined by Dominic Man” The Bread Monk”as “the duration during which, under specified circumstances of storage, after manufacture or packing, a food product will remain safe and suitable for consumption. “In other words, it must maintain the desired sensory, functional, physical, chemical, and microbiological traits over this time. Changes in these characteristics are regarded as quality loss.
Manufacturers strive to save costs, ensure food safety, increase shelf life, and preserve food quality by preventing or delaying mechanisms of food deterioration and spoilage. Three general approaches are taken into consideration:
• inactivating microorganisms;
• suppressing or preventing growth of microbes;
• and limiting microbe access to items.
We first study the many types of spoilage and its known favourable conditions in bakery products before talking about these strategies.
Spoilage by moulds
Moulds are the main cause of product spoilage for bakeries and are expensive owing to lost raw materials and finished goods. Unlike yeasts, which have a single cell, these microorganisms are a form of fungi that have numerous cells.Moulds prefer the presence of water; hence they usually develop in bakery products like bread, cakes, and creams that have a high-water activity (aw) level.
Spoilage by bacteria
Additionally, baked goods may become contaminated by bacteria. Bacillus subtilis spores, for instance, are heat resistant and won't be destroyed by baking. The process that causes bread to become “ropy” like Bacillus cereus14 involves several different Bacillus species. The spores need warm, humid conditions to germinate and develop, generating the distinctive stringy brown mass that smells like fruit. As the food continues to decay, extracellular slimy polysaccharides typical of “rope” are produced, which cause the crumb to disintegrate and turn soft and sticky.
Spoilage by yeasts
In addition to bacteria and moulds, yeasts are a less evident microorganism that contributes to the deterioration of bakery goods. Yeast-related issues can be split into two categories. The first kind of yeasts can be seen because they appear as white or pinkish patches on the bread's surface. Pichia burtonii is the principal cause of surface deterioration in bread; as a result, the phrase “chalk” bread was coined. Furthermore, osmophilic yeasts such Zygosaccharomyces rouxii, which are adapted to thrive in high sugar concentrations like highly sweetened toppings and fillings, can cause fermentative spoiling, which is connected to alcoholic and essence odours.
With this we are going to end this blog, hope you have found this information interesting. Stay tuned for the next blog, which will cover all the internal factors that influence the shelf life of various bakery products. If there is anything you want to explain or take up as our next blog, so write to us in the comment section.
