Slide 1

Hii, Law - Quality Evolution During Drying of FVFs

ids mg Lycopene/ kg DW

mg β-Carotene

Pepper fruits Navarro et al. (2006)

Ascorbic acid

HPLC Mg/100 ml Orange Rapisarda et al.

(2008)

Titration method -

indophenol solu-

tion

Percent of anhydrous

citric acid (%)

Fruits Lim et al. (2007)

RE=Rutin equivalents (a flavonoid type compound)’ FAE=Ferulic acid equivalents,
QE=quercetin equivalents

6.2.4. Biological aspects

Microbial growth on food product is a critical issue that cannot be tolerated. Infor-
mation on microbiological specifications (Mould and yeast, E. coli, Salmonella and etc...)
can be obtained from government and health related authorities (WHO, FAO and ICMSF
etc.) but specifications may vary among countries. Failure to comply with these specifi-
cations could cause fatality upon consumption of the food product.

Another aspect of food safety that is a serious concern to human health is contami-
nation of mycotoxins in food products. Mycotoxins have been shown to be potent carci-
nogens, mutagens and tetratogens. The most important groups of mycotoxins present in
food are aflatoxins, ochratoxins, trichothecenes, zearzlenone and fumonisins. The occur-
rence of these toxins can be traced prior to harvest and also during storage if moisture
exceeds the critical value for mould growth (aw=0.65). The most common mycotoxin-
producing fungi are Aspergillius flavus, Aspergillius parasiticus, Aspergillius ochraceus,
fusarium verticillioides, Fusarium graminearum and Penicillium spp. (Kumar et al.,
2008 ).

The current EU standard for total aflatoxins in all food is 4 ng/g (other than peanuts)
and 15 ng/g in peanuts (Wu, 2008). Many countries have regulatory standards on myco-
toxins in food products and vary among countries.

6.2.5. Sensory properties

Sensory evaluation is another aspect of food quality control that needs to be empha-
sized in food product development. It comprises of appearance, odour, flavour and tex-
ture of the food products. It is a method of accurate measurement of human responses
to foods with minimal biasing effects. A successful product must meet the physical,
chemical and microbiological parameters as well as the sensory expectations as de-
manded by consumers. Elortondo (2007) proposed a general approach for the develop-
ment of an accredicted sensory method for the quality evaluation of food and beverages.
Figure 6. 3 shows examples of some of the common sensory attributes for food products.
Reference sample is given with pre-defined intensity scores associated with the product
during evaluation. Therefore, the selection of the sensory attributes is crucial and it
should cover the essential favour notes of the food product.

Most sensory attributes can be correlated to the physical and chemical properties of
the food product. Szczesniak (2002) correlated sensory and instrumental ratings for
hardness, chewiness, adhesiveness, brittleness, gumminess and viscosity. Acidity and