Section 4. There shall not be used in bakery products or in the ingredients thereof any ingredient or material, including water, which is spoiled or contaminated or which may render the product unwholesome, unfit for food or injurious to health, nor shall there be used in any bakery product any ingredient likely to deceive the consumer or which lessens the nutritive value of such product unless the product is plainly so labelled, branded or tagged, or has thereon a sign making plain to the purchaser or consumer the actual ingredients thereof; provided, that in the case of unwrapped bread to be sold by the loaf such labelling, branding or tagging shall be placed upon the label required under section eight, showing the name of the manufacturer and the net weight of the loaf. Said ingredients and the sale and offering for sale of said products shall otherwise comply with sections one hundred and eighty-six to one hundred and ninety-five, inclusive.