How it works
Quality control of ingredients involves eight basic steps:1
- Establishing specifications for each ingredient based on its chemical composition, nature and technological functionality
- Performing standardized tests and analyzing samples
- Comparing results against a standard or expected property value
- Accepting or rejecting a lot or batch of ingredients received at the bakery upon purchasing
- Communicating results with suppliers
- Implementing corrective actions to close any gaps regarding the quality of a given material
- Improving any condition in a given ingredient that might have the potential to negatively affect the quality of the baked goods
- Recording all out-of-specification incidences for the benefit of monitoring and supplier reviews.
The starting point for the quality control of baking ingredients is the establishment of specifications. They should be properly set by the R&D department and mutually agreed between supplier and bakery in terms related to the use and against reasonable analytical procedures. The QA/QC department should be able to make analytical checks using similar methods to those in the supplier’s laboratory.
Quality control for baking ingredients encompasses:
- Physicochemical parameters related to technological functionality (e.g. solids content, protein content, ash content, moisture content, particle size distribution)
- Microbiological specifications (aerobic mesophilic count, mold count, absence of pathogenic bacteria)
- Maximum or permissible levels of food contaminants (e.g. mycotoxins and heavy metals)
- Rheological tests, both fundamental and empirical (e.g. farinograph, mixolab, alveograph, RVA)
- Specialized tests (e.g. yeast gassing power, fermentable solids, enzyme level/activity)
In an ideal world a bakery would make each product with exactly the same quality characteristics, and this would satisfy customers 100% of the time. However, in the real world, bakers know that their products will have some slight variations in the production process. Bakery managers and plant staff should measure these variations and exert control over them in such a way that the consumers do not notice big variations in product quality.
Quality control of ingredients is the first line of defense against inherent process and ingredient variability. Generally speaking, customer complaints normally can be classified into the following categories:
- Foreign material in the finished product. This could be anything from dirt, whole wheat dough in a white pan bread, sesame seeds in a product that should not contain them, pieces of cloth, brittle plastic, glass, metal, etc. In summary, the product contains something that does not belong there.
- Violation of label declarations. This happens if a product is underweight, contains an undeclared allergen, or does not comply with labeled amounts of sodium, fat, or trans-fat.
- Shelf life issues. This could be due to the presence of mold or undesirable change in texture as in the case of stale bread.
- Off-flavors or off-aromas. This could be due to undesirable enzymatic activity or microorganisms.
- Poor product quality. This could involve breakdown of icings, melting of chocolate enrobing, bread with low volume, cakes with too open grain and tunneling, texture problems, color problems, symmetry problems.
- Physically damaged product. Smashed, leaking, change of appearance.
How often a given ingredient is tested or analyzed should be based on how critical the raw material is or how important it is for keeping product quality. For example, wheat flour and yeast should have specific quality control schedules and procedures to always have the best materials for bread and cakes production
The clean label trend is forcing bakers to replace traditional dough conditioners with functional enzymes which can provide similar functionality and dough/batter processability. In this case, enzymes become a critical and key ingredient that ensures the quality characteristics expected by customers. In such scenarios it would be reasonable to implement testing methods to assess enzymatic activity of amylases, oxidases, lipases and xylanases.
- Vasconcellos, J.A. “Ingredient Specifications and Supplier Verification Program.” Quality Assurance for the Food Industry: A Practical Approach, CRC Press LLC, 2005, pp. 119–139.